litmus-rt.git - The LITMUS^RT kernel.

	Commit message (Collapse)	Author	Age
*	Merge rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6	Dmitry Torokhov	2006-04-29
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\| *	[PATCH] slab: fix crash on __drain_alien_cahce() during CPU Hotplug	shin, jacob	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	transfer_objects should only be called when all of the cpus in the node are online. CPU_DEAD notifier callback marks l3->shared to NULL. Signed-off-by: Jacob Shin <jacob.shin@amd.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] asiliantfb: Add help text in Kconfig	Antonino A. Daplas	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Add help text in Kconfig Signed-off-by: Antonino Daplas <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] suspend: Documentation update for IBM Thinkpad X30	Antonino A. Daplas	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	As reported in Bugzilla Bug 6406, resume from S3 results in a blank screen. For the IBM Thinkpad X30 using vesafb as the console driver, successful resume from S3 requires option acpi_sleep=s3_bios,s3_mode. Update documentation. I would presume that, in any hardware, using vesafb as the console driver will require as a minimum s3_mode. Signed-off-by: Antonino Daplas <adaplas@pol.net> Cc: <igor47@uchicago.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: new system calls	Martin Schwidefsky	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Add sys_set_robust_list, sys_get_robust_list, sys_splice, sys_sync_file and sys_tee system calls. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: dasd device identifiers	Horst Hummel	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Generate new sysfs-attribute 'uid' that contains an device specific unique identifier. This can be used to identity multiple ALIASES of the same physical device (PAV). In addition the sysfs-attributes 'vendor' (containing the manufacturer of the device) and 'alias' (identify alias or base device) is added. This is first part of PAV support in LPAR (also valid on zVM). Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: add read_mostly optimization	Christian Borntraeger	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Add a read_mostly section and define __read_mostly to prevent cache line pollution due to writes for mostly read variables. In addition fix the incorrect alignment of the cache_line_aligned data section. s390 has a cacheline size of 256 bytes. Signed-off-by: Christian Borntraeger <cborntra@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: instruction processing damage handling	Heiko Carstens	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	In case of an instruction processing damage (IPD) machine check in kernel mode the resulting action is always to stop the kernel. This is not necessarily the best solution since a retry of the failing instruction might succeed. Add logic to retry the instruction if no more than 30 instruction processing damage checks occured in the last 5 minutes. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: segment operation error codes	Gerald Schaefer	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Print a warning with the z/VM error code if segment_load, segment_type or segment_save fail to ease the problem determination. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: tape 3590 changes	Stefan Bader	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Added some changes that where proposed by Andrew Morton. Added 3592 device type. Signed-off-by: Stefan Bader <shbader@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: futex atomic operations	Martin Schwidefsky	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Add support for atomic futex operations. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: fix slab debugging	Christian Borntraeger	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	With CONFIG_SLAB_DEBUG=y networking over qeth doesn't work. The problem is that the qib structure embedded in the qeth_irq structure needs an alignment of 256 but kmalloc only guarantees an alignment of 8. When using SLAB debugging the alignment of qeth_irq is not sufficient for the embedded qib structure which causes all users of qdio (qeth and zfcp) to stop working. Allocate qeth_irq structure with __get_free_page. That wastes a small amount of memory (~2500 bytes) per online adapter. Signed-off-by: Christian Borntraeger <cborntra@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: dasd ioctl never returns	Horst Hummel	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	The dasd state machine is not designed to enable an unformatted device, since 'unformatted' is a final state. The BIODASDENABLE ioctl calls dasd_enable_device() which never returns if the device is in this special state. Return -EPERM in dasd_increase_state for unformatted devices to make dasd_enable_device terminate. Note: To get such an unformatted device online it has to be re-analyzed. This means that the device needs to be disabled prior to re-enablement. Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: qdio memory allocations	Andreas Herrmann	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Avoid memory allocation with GFP_KERNEL in qdio_establish/qdio_shutdown. Use memory pool instead. (Otherwise this can lead to an I/O stall where qdio waits for a free page and zfcp waits for end of error recovery in low memory situations.) Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: alternate signal stack handling bug	Laurent Meyer	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	If a signal handler has been established with the SA_ONSTACK option but no alternate stack is provided with sigaltstack(), the kernel still tries to install the alternate stack. Also when setting an alternate stack with sigalstack() and the SS_DISABLE flag, the kernel tries to install the alternate stack on signal delivery. Use the correct conditions sas_ss_flags() to check if the alternate stack has to be used. Signed-off-by: Laurent Meyer <meyerlau@fr.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: enable interrupts on error path	Stefan Bader	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Interrupts can stay disabled if an error occurred in _chp_add(). Use spin_unlock_irq on the error paths to reenable interrupts. Signed-off-by: Stefan Bader <shbader@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] s390: fix I/O termination race in cio	Peter Oberparleiter	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Fix a race condition in the I/O termination logic. The race can cause I/O to a dasd device to fail with no retry left after turning one channel path to the device off and on multiple times. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] kprobe: fix resume execution on i386	Masami Hiramatsu	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Fix resume_execution() to handle iret and absolute jump opcode correctly on i386. Signed-off-by: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com> Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Yumiko Sugita <sugita@sdl.hitachi.co.jp> Cc: Satoshi Oshima <soshima@redhat.com> Cc: Hideo Aoki <haoki@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] kprobe cleanup for VM_MASK judgement	mao, bibo	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	When trap happens in user space, kprobe_exceptions_notify() funtion will skip it. This patch deletes some unnecessary code for VM_MASK judgement in eflags. Signed-off-by: bibo, mao <bibo.mao@intel.com> Cc: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Acked-by: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com> Acked-by: Prasanna S Panchamukhi <prasanna@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Yumiko Sugita <sugita@sdl.hitachi.co.jp> Cc: Satoshi Oshima <soshima@redhat.com> Cc: Hideo Aoki <haoki@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] Mark VMSPLIT EMBEDDED	Andi Kleen	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Running abnormal VM splits causes weird problems - people can set non-standard splits by accident, then lots of time gets wasted diagnosing it - see the long "[stable] 2.6.16.6 breaks java... sort of" email thread. So we need to make this option harder to set. Use CONFIG_EMBEDDED for this. CONFIG_EMBEDDED isn't really the right thing to use, but there's nothing else obvious and avoiding these problems is more important than Kconfig purity. Signed-off-by: Andi Kleen <ak@suse.de> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] enable X86_PC for HOTPLUG_CPU	Ashok Raj	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	CPU_HOTPLUG has race conditions when we use broadcast mode IPI. - First we introduced no_broadcast option (see include/asm-i386/mach-default/mach_ipi.h) - x86_64 solved it by using physical flat mode (same as bigsmp on i386) since this will not use broadcast shortcuts for IPI. - We switched to use bigsmp on i386 so that we can have same handling as x86_64, but apparently this caused an error message, if kernel was compiled without X86_GENERICARCH, X86_BIGSMP. The message "You have >8 CPUS..." which was bogus and misleading, and only indicated one of the above ARCH wasnt selected. So we do not switch to automatic bigsmp for HOTPLUG_CPU support in i386 until the other related config dependencies for SMP_SUSPEND etc can be done right. Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] Avoid printing pointless tsc skew msgs	Dave Jones	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	These messages are kinda silly.. CPU#0 had 0 usecs TSC skew, fixed it up. CPU#1 had 0 usecs TSC skew, fixed it up. inspired from: http://bugzilla.kernel.org/attachment.cgi?id=7713&action=view Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] re-add the OSS SOUND_CS4232 option	Adrian Bunk	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	A regression in the ALSA driver compared to the OSS driver was reported as ALSA bug #1520, so let's keep the OSS driver for now. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] fix array overrun in drivers/char/mwave/mwavedd.c	Eric Sesterhenn	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	this fixes coverity id #489. Since the last element in the array is always ARRAY_SIZE-1 we have to check for ipcnum >= ARRAY_SIZE() Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] tipar oops fix	Daniel Drake	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	If compiled into the kernel, parport_register_driver() is called before the parport driver has been initalised. This means that it is expected that tp_count is 0 after the parport_register_driver() call() - tipar's attach function will not be called until later during bootup. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] request_irq(): remove warnings from irq probing	Andrew Morton	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	- Add new SA_PROBEIRQ which suppresses the new sharing-mismatch warning. Some drivers like to use request_irq() to find an unused interrupt slot. - Use it in i82365.c - Kill unused SA_PROBE. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	[PATCH] off-by-1 in kernel/power/main.c	dean gaudet	2006-04-28
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	There's an off-by-1 in kernel/power/main.c:state_store() ... if your kernel just happens to have some non-zero data at pm_states[PM_SUSPEND_MAX] (i.e. one past the end of the array) then it'll let you write anything you want to /sys/power/state and in response the box will enter S5. Signed-off-by: dean gaudet <dean@arctic.org> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
\| *	Merge branch 'release' of ↵	Linus Torvalds	2006-04-27
\| \|\ \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: [IA64] update sn2 defconfig [IA64] Add mca recovery failure messages [IA64-SGI] fix SGI Altix tioce_reserve_m32() bug [IA64] enable dumps to capture second page of kernel stack [IA64-SGI] - Reduce overhead of reading sn_topology [IA64-SGI] - Fix discover of nearest cpu node to IO node [IA64] IOC4 config option ordering [IA64] Setup an IA64 specific reclaim distance [IA64] eliminate compile time warnings [IA64] eliminate compile time warnings [IA64-SGI] SN SAL call to inject memory errors [IA64] - Fix MAX_PXM_DOMAINS for systems with > 256 nodes [IA64] Remove unused variable in sn_sal.h [IA64] Remove redundant NULL checks before kfree [IA64] wire up compat_sys_adjtimex()
\| \| *	[IA64] update sn2 defconfig	Jes Sorensen	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Update SN2 defconfig to latest kernel and add QLA FC drivers commonly found in SN2 boxes. Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] Add mca recovery failure messages	Russ Anderson	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	When the mca recovery code encounters a condition that makes the MCA non-recoverable, print the reason it could not recover. This will make it easier to identify why the recovery code did not recover. Signed-off-by: Russ Anderson <rja@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64-SGI] fix SGI Altix tioce_reserve_m32() bug	Mike Habeck	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	The following patch fixes a bug in the SGI Altix tioce_reserve_m32() code. The bug was that we could walking past the end of the CE ASIC 32/40bit PMU ATE Buffer, resulting in a PIO Reply Error. Signed-off-by: Mike Habeck <habeck@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] enable dumps to capture second page of kernel stack	Cliff Wickman	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	In SLES10 (2.6.16) crash dumping (in my experience, LKCD) is unable to capture the second page of the 2-page task/stack allocation. This is particularly troublesome for dump analysis, as the stack traceback cannot be done. (A similar convention is probably needed throughout the kernel to make kernel multi-page allocations detectable for dumping) Multi-page kernel allocations are represented by the single page structure associated with the first page of the allocation. The page structures associated with the other pages are unintialized. If the dumper is selecting only kernel pages it has no way to identify any but the first page of the allocation. The fix is to make the task/stack allocation a compound page. Signed-off-by: Cliff Wickman <cpw@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64-SGI] - Reduce overhead of reading sn_topology	Jack Steiner	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	MPI programs using certain debug options have a long startup time. This was traced to a "vmalloc/vfree" in the code that reads /proc/sgi_sn/sn_topology. On large systems, vfree requires an IPI to all cpus to do TLB purging. Replace the vmalloc/vfree with kmalloc/kfree. Although the size of the structure being allocated is unknown, it will not not exceed 96 bytes. Signed-off-by: Jack Steiner <steiner@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64-SGI] - Fix discover of nearest cpu node to IO node	Jack Steiner	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Fix a bug that causes discovery of the nearest node/cpu to a TIO (IO node) to fail. Signed-off-by: Jack Steiner <steiner@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] IOC4 config option ordering	Brent Casavant	2006-04-21
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	SERIAL_SGI_IOC4 and BLK_DEV_SGIIOC4 depend upon SGI_IOC4, and SERIAL_SGI_IOC3 depends upon SGI_IOC3. Currently the definitions are out of order in the config sequence. Fix by including drivers/sn/Kconfig immediately after SGI_SN, upon which SGI_IOC4 and SGI_IOC3 depend. Signed-off-by: Brent Casavant <bcasavan@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] Setup an IA64 specific reclaim distance	Christoph Lameter	2006-04-21
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	RECLAIM_DISTANCE is checked on bootup against the SLIT table distances. Zone reclaim is important for system that have higher latencies but not for systems that have multiple nodes on one motherboard and therefore low latencies. We found that on motherboard latencies are typically 1 to 1.4 of local memory access speed whereas multinode systems which benefit from zone reclaim have usually more than 1.5 times the latency of a local access. Set the reclaim distance for IA64 to 1.5 times. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] eliminate compile time warnings	Satoru Takeuchi	2006-04-20
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	This patch removes following compile time warnings: drivers/pci/pci-sysfs.c: In function `pci_read_legacy_io': drivers/pci/pci-sysfs.c:257: warning: implicit declaration of function `ia64_pci_legacy_read' drivers/pci/pci-sysfs.c: In function `pci_write_legacy_io': drivers/pci/pci-sysfs.c:280: warning: implicit declaration of function `ia64_pci_legacy_write' It also fixes wrong definition of ia64_pci_legacy_write (type of `bus' is not `pci_dev', but `pci_bus'). Signed-Off-By: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] eliminate compile time warnings	Satoru Takeuchi	2006-04-20
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	This is a trivial patch to remove following compile time warning: arch/ia64/ia32/../../../fs/binfmt_elf.c:508: warning: 'randomize_stack_top' defined but not used Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64-SGI] SN SAL call to inject memory errors	Russ Anderson	2006-04-20
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	The SGI Altix SAL provides an interface for modifying the ECC on memory to create memory errors. The SAL call can be used to inject memory errors for testing MCA recovery code. Signed-off-by: Russ Anderson (rja@sgi.com) Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] - Fix MAX_PXM_DOMAINS for systems with > 256 nodes	Jack Steiner	2006-04-20
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Correctly size the PXM-related arrays for systems that have more than 256 nodes. Signed-off-by: Jack Steiner <steiner@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] Remove unused variable in sn_sal.h	Russ Anderson	2006-04-20
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	cnodeid was being set but not used. The dead code was left over from a previous version that grabbed a per node lock. Signed-off-by: Russ Anderson (rja@sgi.com) Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] Remove redundant NULL checks before kfree	Jesper Juhl	2006-04-20
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| \| *	[IA64] wire up compat_sys_adjtimex()	Luck, Tony	2006-04-20
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
\| * \|	Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6	Linus Torvalds	2006-04-27
\| \|\ \ \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6: [PATCH] PCI quirk: VIA IRQ fixup should only run for VIA southbridges [PATCH] PCI: fix potential resource leak in drivers/pci/msi.c [PATCH] PCI: Documentation: no more device ids [PATCH] PCI: fix via irq SATA patch
\| \| * \|	[PATCH] PCI quirk: VIA IRQ fixup should only run for VIA southbridges	Chris Wedgwood	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Alan Cox pointed out that the VIA 'IRQ fixup' was erroneously running on my system which has no VIA southbridge (but I do have a VIA IEEE 1394 device). This should address that. I also changed "Via IRQ" to "VIA IRQ" (initially I read Via as a capitalized via (by way/means of). Signed-off-by: Chris Wedgwood <cw@f00f.org> Acked-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
\| \| * \|	[PATCH] PCI: fix potential resource leak in drivers/pci/msi.c	Jesper Juhl	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	The coverity checker spotted (as entry #599) that we might leak `entry' in drivers/pci/msi.c::msix_capability_init() This patch should take care of that. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
\| \| * \|	[PATCH] PCI: Documentation: no more device ids	Ingo Oeser	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	Document that we don't like to add more PCI device ids but are happy to accept PCI vendor ids for linux/include/pci_ids.h Original text from Jeff Garzik. Signed-off-by: Ingo Oeser <netdev@axxeo.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
\| \| * \|	[PATCH] PCI: fix via irq SATA patch	Greg Kroah-Hartman	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	This device id improperly got added to the VIA chipset list with a previous patch. Remove it as it is not correct. Cc: Grzegorz Janoszka <Grzegorz@Janoszka.pl> Cc: Jeff Garzik <jeff@garzik.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
\| * \| \|	Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6	Linus Torvalds	2006-04-27
\| \|\ \ \ \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6: [PATCH] USB: ftdi_sio: add support for ASK RDR 400 series card reader [PATCH] USB: ftdi_sio: Adds support for iPlus device. [PATCH] USB: ftdi_sio vendor code for RR-CirKits LocoBuffer USB [PATCH] USB: Use new PCI_CLASS_SERIAL_USB_* defines [PATCH] USB: net2280: set driver data before it is used [PATCH] USB: net2280: check for shared IRQs [PATCH] USB: net2280: send 0-length packets for ep0 [PATCH] USB: net2280: Handle STALLs for 0-length control-IN requests [PATCH] USB: storage: atmel unusual dev update [PATCH] USB: Storage: unusual devs update [PATCH] USB: add new iTegno usb CDMA 1x card support for pl2303 [PATCH] USB: Resource leak fix for whiteheat driver
\| \| * \| \|	[PATCH] USB: ftdi_sio: add support for ASK RDR 400 series card reader	Ian Abbott	2006-04-27
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	This patch adds support for an ASK RDR 400 series contactless card reader <http://www.ask.fr/uk/products_and_services/terminals.html> to the ftdi_sio driver's device ID table. The product ID was supplied by Adriano Couto on the ftdi-usb-sio-devel list. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

/* memcontrol.c - Memory Controller * * Copyright IBM Corporation, 2007 * Author Balbir Singh <balbir@linux.vnet.ibm.com> * * Copyright 2007 OpenVZ SWsoft Inc * Author: Pavel Emelianov <xemul@openvz.org> * * Memory thresholds * Copyright (C) 2009 Nokia Corporation * Author: Kirill A. Shutemov * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/res_counter.h> #include <linux/memcontrol.h> #include <linux/cgroup.h> #include <linux/mm.h> #include <linux/hugetlb.h> #include <linux/pagemap.h> #include <linux/smp.h> #include <linux/page-flags.h> #include <linux/backing-dev.h> #include <linux/bit_spinlock.h> #include <linux/rcupdate.h> #include <linux/limits.h> #include <linux/export.h> #include <linux/mutex.h> #include <linux/rbtree.h> #include <linux/slab.h> #include <linux/swap.h> #include <linux/swapops.h> #include <linux/spinlock.h> #include <linux/eventfd.h> #include <linux/sort.h> #include <linux/fs.h> #include <linux/seq_file.h> #include <linux/vmalloc.h> #include <linux/mm_inline.h> #include <linux/page_cgroup.h> #include <linux/cpu.h> #include <linux/oom.h> #include "internal.h" #include <net/sock.h> #include <net/tcp_memcontrol.h> #include <asm/uaccess.h> #include <trace/events/vmscan.h> struct cgroup_subsys mem_cgroup_subsys __read_mostly; #define MEM_CGROUP_RECLAIM_RETRIES 5 struct mem_cgroup *root_mem_cgroup __read_mostly; #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP /* Turned on only when memory cgroup is enabled && really_do_swap_account = 1 */ int do_swap_account __read_mostly; /* for remember boot option*/ #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED static int really_do_swap_account __initdata = 1; #else static int really_do_swap_account __initdata = 0; #endif #else #define do_swap_account (0) #endif /* * Statistics for memory cgroup. */ enum mem_cgroup_stat_index { /* * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. */ MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */ MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ MEM_CGROUP_STAT_DATA, /* end of data requires synchronization */ MEM_CGROUP_ON_MOVE, /* someone is moving account between groups */ MEM_CGROUP_STAT_NSTATS, }; enum mem_cgroup_events_index { MEM_CGROUP_EVENTS_PGPGIN, /* # of pages paged in */ MEM_CGROUP_EVENTS_PGPGOUT, /* # of pages paged out */ MEM_CGROUP_EVENTS_COUNT, /* # of pages paged in/out */ MEM_CGROUP_EVENTS_PGFAULT, /* # of page-faults */ MEM_CGROUP_EVENTS_PGMAJFAULT, /* # of major page-faults */ MEM_CGROUP_EVENTS_NSTATS, }; /* * Per memcg event counter is incremented at every pagein/pageout. With THP, * it will be incremated by the number of pages. This counter is used for * for trigger some periodic events. This is straightforward and better * than using jiffies etc. to handle periodic memcg event. */ enum mem_cgroup_events_target { MEM_CGROUP_TARGET_THRESH, MEM_CGROUP_TARGET_SOFTLIMIT, MEM_CGROUP_TARGET_NUMAINFO, MEM_CGROUP_NTARGETS, }; #define THRESHOLDS_EVENTS_TARGET (128) #define SOFTLIMIT_EVENTS_TARGET (1024) #define NUMAINFO_EVENTS_TARGET (1024) struct mem_cgroup_stat_cpu { long count[MEM_CGROUP_STAT_NSTATS]; unsigned long events[MEM_CGROUP_EVENTS_NSTATS]; unsigned long targets[MEM_CGROUP_NTARGETS]; }; struct mem_cgroup_reclaim_iter { /* css_id of the last scanned hierarchy member */ int position; /* scan generation, increased every round-trip */ unsigned int generation; }; /* * per-zone information in memory controller. */ struct mem_cgroup_per_zone { struct lruvec lruvec; unsigned long count[NR_LRU_LISTS]; struct mem_cgroup_reclaim_iter reclaim_iter[DEF_PRIORITY + 1]; struct zone_reclaim_stat reclaim_stat; struct rb_node tree_node; /* RB tree node */ unsigned long long usage_in_excess;/* Set to the value by which */ /* the soft limit is exceeded*/ bool on_tree; struct mem_cgroup *mem; /* Back pointer, we cannot */ /* use container_of */ }; /* Macro for accessing counter */ #define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)]) struct mem_cgroup_per_node { struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES]; }; struct mem_cgroup_lru_info { struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES]; }; /* * Cgroups above their limits are maintained in a RB-Tree, independent of * their hierarchy representation */ struct mem_cgroup_tree_per_zone { struct rb_root rb_root; spinlock_t lock; }; struct mem_cgroup_tree_per_node { struct mem_cgroup_tree_per_zone rb_tree_per_zone[MAX_NR_ZONES]; }; struct mem_cgroup_tree { struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES]; }; static struct mem_cgroup_tree soft_limit_tree __read_mostly; struct mem_cgroup_threshold { struct eventfd_ctx *eventfd; u64 threshold; }; /* For threshold */ struct mem_cgroup_threshold_ary { /* An array index points to threshold just below usage. */ int current_threshold; /* Size of entries[] */ unsigned int size; /* Array of thresholds */ struct mem_cgroup_threshold entries[0]; }; struct mem_cgroup_thresholds { /* Primary thresholds array */ struct mem_cgroup_threshold_ary *primary; /* * Spare threshold array. * This is needed to make mem_cgroup_unregister_event() "never fail". * It must be able to store at least primary->size - 1 entries. */ struct mem_cgroup_threshold_ary *spare; }; /* for OOM */ struct mem_cgroup_eventfd_list { struct list_head list; struct eventfd_ctx *eventfd; }; static void mem_cgroup_threshold(struct mem_cgroup *memcg); static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); /* * The memory controller data structure. The memory controller controls both * page cache and RSS per cgroup. We would eventually like to provide * statistics based on the statistics developed by Rik Van Riel for clock-pro, * to help the administrator determine what knobs to tune. * * TODO: Add a water mark for the memory controller. Reclaim will begin when * we hit the water mark. May be even add a low water mark, such that * no reclaim occurs from a cgroup at it's low water mark, this is * a feature that will be implemented much later in the future. */ struct mem_cgroup { struct cgroup_subsys_state css; /* * the counter to account for memory usage */ struct res_counter res; /* * the counter to account for mem+swap usage. */ struct res_counter memsw; /* * Per cgroup active and inactive list, similar to the * per zone LRU lists. */ struct mem_cgroup_lru_info info; int last_scanned_node; #if MAX_NUMNODES > 1 nodemask_t scan_nodes; atomic_t numainfo_events; atomic_t numainfo_updating; #endif /* * Should the accounting and control be hierarchical, per subtree? */ bool use_hierarchy; bool oom_lock; atomic_t under_oom; atomic_t refcnt; int swappiness; /* OOM-Killer disable */ int oom_kill_disable; /* set when res.limit == memsw.limit */ bool memsw_is_minimum; /* protect arrays of thresholds */ struct mutex thresholds_lock; /* thresholds for memory usage. RCU-protected */ struct mem_cgroup_thresholds thresholds; /* thresholds for mem+swap usage. RCU-protected */ struct mem_cgroup_thresholds memsw_thresholds; /* For oom notifier event fd */ struct list_head oom_notify; /* * Should we move charges of a task when a task is moved into this * mem_cgroup ? And what type of charges should we move ? */ unsigned long move_charge_at_immigrate; /* * percpu counter. */ struct mem_cgroup_stat_cpu *stat; /* * used when a cpu is offlined or other synchronizations * See mem_cgroup_read_stat(). */ struct mem_cgroup_stat_cpu nocpu_base; spinlock_t pcp_counter_lock; #ifdef CONFIG_INET struct tcp_memcontrol tcp_mem; #endif }; /* Stuffs for move charges at task migration. */ /* * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a * left-shifted bitmap of these types. */ enum move_type { MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */ MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */ NR_MOVE_TYPE, }; /* "mc" and its members are protected by cgroup_mutex */ static struct move_charge_struct { spinlock_t lock; /* for from, to */ struct mem_cgroup *from; struct mem_cgroup *to; unsigned long precharge; unsigned long moved_charge; unsigned long moved_swap; struct task_struct *moving_task; /* a task moving charges */ wait_queue_head_t waitq; /* a waitq for other context */ } mc = { .lock = __SPIN_LOCK_UNLOCKED(mc.lock), .waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq), }; static bool move_anon(void) { return test_bit(MOVE_CHARGE_TYPE_ANON, &mc.to->move_charge_at_immigrate); } static bool move_file(void) { return test_bit(MOVE_CHARGE_TYPE_FILE, &mc.to->move_charge_at_immigrate); } /* * Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft * limit reclaim to prevent infinite loops, if they ever occur. */ #define MEM_CGROUP_MAX_RECLAIM_LOOPS (100) #define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS (2) enum charge_type { MEM_CGROUP_CHARGE_TYPE_CACHE = 0, MEM_CGROUP_CHARGE_TYPE_MAPPED, MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */ NR_CHARGE_TYPE, }; /* for encoding cft->private value on file */ #define _MEM (0) #define _MEMSWAP (1) #define _OOM_TYPE (2) #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val)) #define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff) #define MEMFILE_ATTR(val) ((val) & 0xffff) /* Used for OOM nofiier */ #define OOM_CONTROL (0) /* * Reclaim flags for mem_cgroup_hierarchical_reclaim */ #define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0 #define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT) #define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1 #define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT) static void mem_cgroup_get(struct mem_cgroup *memcg); static void mem_cgroup_put(struct mem_cgroup *memcg); /* Writing them here to avoid exposing memcg's inner layout */ #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM #ifdef CONFIG_INET #include <net/sock.h> #include <net/ip.h> static bool mem_cgroup_is_root(struct mem_cgroup *memcg); void sock_update_memcg(struct sock *sk) { if (static_branch(&memcg_socket_limit_enabled)) { struct mem_cgroup *memcg; BUG_ON(!sk->sk_prot->proto_cgroup); /* Socket cloning can throw us here with sk_cgrp already * filled. It won't however, necessarily happen from * process context. So the test for root memcg given * the current task's memcg won't help us in this case. * * Respecting the original socket's memcg is a better * decision in this case. */ if (sk->sk_cgrp) { BUG_ON(mem_cgroup_is_root(sk->sk_cgrp->memcg)); mem_cgroup_get(sk->sk_cgrp->memcg); return; } rcu_read_lock(); memcg = mem_cgroup_from_task(current); if (!mem_cgroup_is_root(memcg)) { mem_cgroup_get(memcg); sk->sk_cgrp = sk->sk_prot->proto_cgroup(memcg); } rcu_read_unlock(); } } EXPORT_SYMBOL(sock_update_memcg); void sock_release_memcg(struct sock *sk) { if (static_branch(&memcg_socket_limit_enabled) && sk->sk_cgrp) { struct mem_cgroup *memcg; WARN_ON(!sk->sk_cgrp->memcg); memcg = sk->sk_cgrp->memcg; mem_cgroup_put(memcg); } } struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg) { if (!memcg || mem_cgroup_is_root(memcg)) return NULL; return &memcg->tcp_mem.cg_proto; } EXPORT_SYMBOL(tcp_proto_cgroup); #endif /* CONFIG_INET */ #endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */ static void drain_all_stock_async(struct mem_cgroup *memcg); static struct mem_cgroup_per_zone * mem_cgroup_zoneinfo(struct mem_cgroup *memcg, int nid, int zid) { return &memcg->info.nodeinfo[nid]->zoneinfo[zid]; } struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg) { return &memcg->css; } static struct mem_cgroup_per_zone * page_cgroup_zoneinfo(struct mem_cgroup *memcg, struct page *page) { int nid = page_to_nid(page); int zid = page_zonenum(page); return mem_cgroup_zoneinfo(memcg, nid, zid); } static struct mem_cgroup_tree_per_zone * soft_limit_tree_node_zone(int nid, int zid) { return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; } static struct mem_cgroup_tree_per_zone * soft_limit_tree_from_page(struct page *page) { int nid = page_to_nid(page); int zid = page_zonenum(page); return &soft_limit_tree.rb_tree_per_node[nid]->rb_tree_per_zone[zid]; } static void __mem_cgroup_insert_exceeded(struct mem_cgroup *memcg, struct mem_cgroup_per_zone *mz, struct mem_cgroup_tree_per_zone *mctz, unsigned long long new_usage_in_excess) { struct rb_node **p = &mctz->rb_root.rb_node; struct rb_node *parent = NULL; struct mem_cgroup_per_zone *mz_node; if (mz->on_tree) return; mz->usage_in_excess = new_usage_in_excess; if (!mz->usage_in_excess) return; while (*p) { parent = *p; mz_node = rb_entry(parent, struct mem_cgroup_per_zone, tree_node); if (mz->usage_in_excess < mz_node->usage_in_excess) p = &(*p)->rb_left; /* * We can't avoid mem cgroups that are over their soft * limit by the same amount */ else if (mz->usage_in_excess >= mz_node->usage_in_excess) p = &(*p)->rb_right; } rb_link_node(&mz->tree_node, parent, p); rb_insert_color(&mz->tree_node, &mctz->rb_root); mz->on_tree = true; } static void __mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, struct mem_cgroup_per_zone *mz, struct mem_cgroup_tree_per_zone *mctz) { if (!mz->on_tree) return; rb_erase(&mz->tree_node, &mctz->rb_root); mz->on_tree = false; } static void mem_cgroup_remove_exceeded(struct mem_cgroup *memcg, struct mem_cgroup_per_zone *mz, struct mem_cgroup_tree_per_zone *mctz) { spin_lock(&mctz->lock); __mem_cgroup_remove_exceeded(memcg, mz, mctz); spin_unlock(&mctz->lock); } static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) { unsigned long long excess; struct mem_cgroup_per_zone *mz; struct mem_cgroup_tree_per_zone *mctz; int nid = page_to_nid(page); int zid = page_zonenum(page); mctz = soft_limit_tree_from_page(page); /* * Necessary to update all ancestors when hierarchy is used. * because their event counter is not touched. */ for (; memcg; memcg = parent_mem_cgroup(memcg)) { mz = mem_cgroup_zoneinfo(memcg, nid, zid); excess = res_counter_soft_limit_excess(&memcg->res); /* * We have to update the tree if mz is on RB-tree or * mem is over its softlimit. */ if (excess || mz->on_tree) { spin_lock(&mctz->lock); /* if on-tree, remove it */ if (mz->on_tree) __mem_cgroup_remove_exceeded(memcg, mz, mctz); /* * Insert again. mz->usage_in_excess will be updated. * If excess is 0, no tree ops. */ __mem_cgroup_insert_exceeded(memcg, mz, mctz, excess); spin_unlock(&mctz->lock); } } } static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg) { int node, zone; struct mem_cgroup_per_zone *mz; struct mem_cgroup_tree_per_zone *mctz; for_each_node_state(node, N_POSSIBLE) { for (zone = 0; zone < MAX_NR_ZONES; zone++) { mz = mem_cgroup_zoneinfo(memcg, node, zone); mctz = soft_limit_tree_node_zone(node, zone); mem_cgroup_remove_exceeded(memcg, mz, mctz); } } } static struct mem_cgroup_per_zone * __mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) { struct rb_node *rightmost = NULL; struct mem_cgroup_per_zone *mz; retry: mz = NULL; rightmost = rb_last(&mctz->rb_root); if (!rightmost) goto done; /* Nothing to reclaim from */ mz = rb_entry(rightmost, struct mem_cgroup_per_zone, tree_node); /* * Remove the node now but someone else can add it back, * we will to add it back at the end of reclaim to its correct * position in the tree. */ __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); if (!res_counter_soft_limit_excess(&mz->mem->res) || !css_tryget(&mz->mem->css)) goto retry; done: return mz; } static struct mem_cgroup_per_zone * mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_zone *mctz) { struct mem_cgroup_per_zone *mz; spin_lock(&mctz->lock); mz = __mem_cgroup_largest_soft_limit_node(mctz); spin_unlock(&mctz->lock); return mz; } /* * Implementation Note: reading percpu statistics for memcg. * * Both of vmstat[] and percpu_counter has threshold and do periodic * synchronization to implement "quick" read. There are trade-off between * reading cost and precision of value. Then, we may have a chance to implement * a periodic synchronizion of counter in memcg's counter. * * But this _read() function is used for user interface now. The user accounts * memory usage by memory cgroup and he _always_ requires exact value because * he accounts memory. Even if we provide quick-and-fuzzy read, we always * have to visit all online cpus and make sum. So, for now, unnecessary * synchronization is not implemented. (just implemented for cpu hotplug) * * If there are kernel internal actions which can make use of some not-exact * value, and reading all cpu value can be performance bottleneck in some * common workload, threashold and synchonization as vmstat[] should be * implemented. */ static long mem_cgroup_read_stat(struct mem_cgroup *memcg, enum mem_cgroup_stat_index idx) { long val = 0; int cpu; get_online_cpus(); for_each_online_cpu(cpu) val += per_cpu(memcg->stat->count[idx], cpu); #ifdef CONFIG_HOTPLUG_CPU spin_lock(&memcg->pcp_counter_lock); val += memcg->nocpu_base.count[idx]; spin_unlock(&memcg->pcp_counter_lock); #endif put_online_cpus(); return val; } static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, bool charge) { int val = (charge) ? 1 : -1; this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_SWAPOUT], val); } static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg, enum mem_cgroup_events_index idx) { unsigned long val = 0; int cpu; for_each_online_cpu(cpu) val += per_cpu(memcg->stat->events[idx], cpu); #ifdef CONFIG_HOTPLUG_CPU spin_lock(&memcg->pcp_counter_lock); val += memcg->nocpu_base.events[idx]; spin_unlock(&memcg->pcp_counter_lock); #endif return val; } static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, bool file, int nr_pages) { preempt_disable(); if (file) __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_pages); else __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_pages); /* pagein of a big page is an event. So, ignore page size */ if (nr_pages > 0) __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGIN]); else { __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]); nr_pages = -nr_pages; /* for event */ } __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT], nr_pages); preempt_enable(); } unsigned long mem_cgroup_zone_nr_lru_pages(struct mem_cgroup *memcg, int nid, int zid, unsigned int lru_mask) { struct mem_cgroup_per_zone *mz; enum lru_list l; unsigned long ret = 0; mz = mem_cgroup_zoneinfo(memcg, nid, zid); for_each_lru(l) { if (BIT(l) & lru_mask) ret += MEM_CGROUP_ZSTAT(mz, l); } return ret; } static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, int nid, unsigned int lru_mask) { u64 total = 0; int zid; for (zid = 0; zid < MAX_NR_ZONES; zid++) total += mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, lru_mask); return total; } static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, unsigned int lru_mask) { int nid; u64 total = 0; for_each_node_state(nid, N_HIGH_MEMORY) total += mem_cgroup_node_nr_lru_pages(memcg, nid, lru_mask); return total; } static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg, enum mem_cgroup_events_target target) { unsigned long val, next; val = __this_cpu_read(memcg->stat->events[MEM_CGROUP_EVENTS_COUNT]); next = __this_cpu_read(memcg->stat->targets[target]); /* from time_after() in jiffies.h */ if ((long)next - (long)val < 0) { switch (target) { case MEM_CGROUP_TARGET_THRESH: next = val + THRESHOLDS_EVENTS_TARGET; break; case MEM_CGROUP_TARGET_SOFTLIMIT: next = val + SOFTLIMIT_EVENTS_TARGET; break; case MEM_CGROUP_TARGET_NUMAINFO: next = val + NUMAINFO_EVENTS_TARGET; break; default: break; } __this_cpu_write(memcg->stat->targets[target], next); return true; } return false; } /* * Check events in order. * */ static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) { preempt_disable(); /* threshold event is triggered in finer grain than soft limit */ if (unlikely(mem_cgroup_event_ratelimit(memcg, MEM_CGROUP_TARGET_THRESH))) { bool do_softlimit, do_numainfo; do_softlimit = mem_cgroup_event_ratelimit(memcg, MEM_CGROUP_TARGET_SOFTLIMIT); #if MAX_NUMNODES > 1 do_numainfo = mem_cgroup_event_ratelimit(memcg, MEM_CGROUP_TARGET_NUMAINFO); #endif preempt_enable(); mem_cgroup_threshold(memcg); if (unlikely(do_softlimit)) mem_cgroup_update_tree(memcg, page); #if MAX_NUMNODES > 1 if (unlikely(do_numainfo)) atomic_inc(&memcg->numainfo_events); #endif } else preempt_enable(); } struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) { return container_of(cgroup_subsys_state(cont, mem_cgroup_subsys_id), struct mem_cgroup, css); } struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) { /* * mm_update_next_owner() may clear mm->owner to NULL * if it races with swapoff, page migration, etc. * So this can be called with p == NULL. */ if (unlikely(!p)) return NULL; return container_of(task_subsys_state(p, mem_cgroup_subsys_id), struct mem_cgroup, css); } struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) { struct mem_cgroup *memcg = NULL; if (!mm) return NULL; /* * Because we have no locks, mm->owner's may be being moved to other * cgroup. We use css_tryget() here even if this looks * pessimistic (rather than adding locks here). */ rcu_read_lock(); do { memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); if (unlikely(!memcg)) break; } while (!css_tryget(&memcg->css)); rcu_read_unlock(); return memcg; } /** * mem_cgroup_iter - iterate over memory cgroup hierarchy * @root: hierarchy root * @prev: previously returned memcg, NULL on first invocation * @reclaim: cookie for shared reclaim walks, NULL for full walks * * Returns references to children of the hierarchy below @root, or * @root itself, or %NULL after a full round-trip. * * Caller must pass the return value in @prev on subsequent * invocations for reference counting, or use mem_cgroup_iter_break() * to cancel a hierarchy walk before the round-trip is complete. * * Reclaimers can specify a zone and a priority level in @reclaim to * divide up the memcgs in the hierarchy among all concurrent * reclaimers operating on the same zone and priority. */ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, struct mem_cgroup *prev, struct mem_cgroup_reclaim_cookie *reclaim) { struct mem_cgroup *memcg = NULL; int id = 0; if (mem_cgroup_disabled()) return NULL; if (!root) root = root_mem_cgroup; if (prev && !reclaim) id = css_id(&prev->css); if (prev && prev != root) css_put(&prev->css); if (!root->use_hierarchy && root != root_mem_cgroup) { if (prev) return NULL; return root; } while (!memcg) { struct mem_cgroup_reclaim_iter *uninitialized_var(iter); struct cgroup_subsys_state *css; if (reclaim) { int nid = zone_to_nid(reclaim->zone); int zid = zone_idx(reclaim->zone); struct mem_cgroup_per_zone *mz; mz = mem_cgroup_zoneinfo(root, nid, zid); iter = &mz->reclaim_iter[reclaim->priority]; if (prev && reclaim->generation != iter->generation) return NULL; id = iter->position; } rcu_read_lock(); css = css_get_next(&mem_cgroup_subsys, id + 1, &root->css, &id); if (css) { if (css == &root->css || css_tryget(css)) memcg = container_of(css, struct mem_cgroup, css); } else id = 0; rcu_read_unlock(); if (reclaim) { iter->position = id; if (!css) iter->generation++; else if (!prev && memcg) reclaim->generation = iter->generation; } if (prev && !css) return NULL; } return memcg; } /** * mem_cgroup_iter_break - abort a hierarchy walk prematurely * @root: hierarchy root * @prev: last visited hierarchy member as returned by mem_cgroup_iter() */ void mem_cgroup_iter_break(struct mem_cgroup *root, struct mem_cgroup *prev) { if (!root) root = root_mem_cgroup; if (prev && prev != root) css_put(&prev->css); } /* * Iteration constructs for visiting all cgroups (under a tree). If * loops are exited prematurely (break), mem_cgroup_iter_break() must * be used for reference counting. */ #define for_each_mem_cgroup_tree(iter, root) \ for (iter = mem_cgroup_iter(root, NULL, NULL); \ iter != NULL; \ iter = mem_cgroup_iter(root, iter, NULL)) #define for_each_mem_cgroup(iter) \ for (iter = mem_cgroup_iter(NULL, NULL, NULL); \ iter != NULL; \ iter = mem_cgroup_iter(NULL, iter, NULL)) static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) { return (memcg == root_mem_cgroup); } void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) { struct mem_cgroup *memcg; if (!mm) return; rcu_read_lock(); memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); if (unlikely(!memcg)) goto out; switch (idx) { case PGFAULT: this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]); break; case PGMAJFAULT: this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]); break; default: BUG(); } out: rcu_read_unlock(); } EXPORT_SYMBOL(mem_cgroup_count_vm_event); /** * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg * @zone: zone of the wanted lruvec * @mem: memcg of the wanted lruvec * * Returns the lru list vector holding pages for the given @zone and * @mem. This can be the global zone lruvec, if the memory controller * is disabled. */ struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone, struct mem_cgroup *memcg) { struct mem_cgroup_per_zone *mz; if (mem_cgroup_disabled()) return &zone->lruvec; mz = mem_cgroup_zoneinfo(memcg, zone_to_nid(zone), zone_idx(zone)); return &mz->lruvec; } /* * Following LRU functions are allowed to be used without PCG_LOCK. * Operations are called by routine of global LRU independently from memcg. * What we have to take care of here is validness of pc->mem_cgroup. * * Changes to pc->mem_cgroup happens when * 1. charge * 2. moving account * In typical case, "charge" is done before add-to-lru. Exception is SwapCache. * It is added to LRU before charge. * If PCG_USED bit is not set, page_cgroup is not added to this private LRU. * When moving account, the page is not on LRU. It's isolated. */ /** * mem_cgroup_lru_add_list - account for adding an lru page and return lruvec * @zone: zone of the page * @page: the page * @lru: current lru * * This function accounts for @page being added to @lru, and returns * the lruvec for the given @zone and the memcg @page is charged to. * * The callsite is then responsible for physically linking the page to * the returned lruvec->lists[@lru]. */ struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page, enum lru_list lru) { struct mem_cgroup_per_zone *mz; struct mem_cgroup *memcg; struct page_cgroup *pc; if (mem_cgroup_disabled()) return &zone->lruvec; pc = lookup_page_cgroup(page); VM_BUG_ON(PageCgroupAcctLRU(pc)); /* * putback: charge: * SetPageLRU SetPageCgroupUsed * smp_mb smp_mb * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU * * Ensure that one of the two sides adds the page to the memcg * LRU during a race. */ smp_mb(); /* * If the page is uncharged, it may be freed soon, but it * could also be swap cache (readahead, swapoff) that needs to * be reclaimable in the future. root_mem_cgroup will babysit * it for the time being. */ if (PageCgroupUsed(pc)) { /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ smp_rmb(); memcg = pc->mem_cgroup; SetPageCgroupAcctLRU(pc); } else memcg = root_mem_cgroup; mz = page_cgroup_zoneinfo(memcg, page); /* compound_order() is stabilized through lru_lock */ MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page); return &mz->lruvec; } /** * mem_cgroup_lru_del_list - account for removing an lru page * @page: the page * @lru: target lru * * This function accounts for @page being removed from @lru. * * The callsite is then responsible for physically unlinking * @page->lru. */ void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru) { struct mem_cgroup_per_zone *mz; struct mem_cgroup *memcg; struct page_cgroup *pc; if (mem_cgroup_disabled()) return; pc = lookup_page_cgroup(page); /* * root_mem_cgroup babysits uncharged LRU pages, but * PageCgroupUsed is cleared when the page is about to get * freed. PageCgroupAcctLRU remembers whether the * LRU-accounting happened against pc->mem_cgroup or * root_mem_cgroup. */ if (TestClearPageCgroupAcctLRU(pc)) { VM_BUG_ON(!pc->mem_cgroup); memcg = pc->mem_cgroup; } else memcg = root_mem_cgroup; mz = page_cgroup_zoneinfo(memcg, page); /* huge page split is done under lru_lock. so, we have no races. */ MEM_CGROUP_ZSTAT(mz, lru) -= 1 << compound_order(page); } void mem_cgroup_lru_del(struct page *page) { mem_cgroup_lru_del_list(page, page_lru(page)); } /** * mem_cgroup_lru_move_lists - account for moving a page between lrus * @zone: zone of the page * @page: the page * @from: current lru * @to: target lru * * This function accounts for @page being moved between the lrus @from * and @to, and returns the lruvec for the given @zone and the memcg * @page is charged to. * * The callsite is then responsible for physically relinking * @page->lru to the returned lruvec->lists[@to]. */ struct lruvec *mem_cgroup_lru_move_lists(struct zone *zone, struct page *page, enum lru_list from, enum lru_list to) { /* XXX: Optimize this, especially for @from == @to */ mem_cgroup_lru_del_list(page, from); return mem_cgroup_lru_add_list(zone, page, to); } /* * At handling SwapCache and other FUSE stuff, pc->mem_cgroup may be changed * while it's linked to lru because the page may be reused after it's fully * uncharged. To handle that, unlink page_cgroup from LRU when charge it again. * It's done under lock_page and expected that zone->lru_lock isnever held. */ static void mem_cgroup_lru_del_before_commit(struct page *page) { enum lru_list lru; unsigned long flags; struct zone *zone = page_zone(page); struct page_cgroup *pc = lookup_page_cgroup(page); /* * Doing this check without taking ->lru_lock seems wrong but this * is safe. Because if page_cgroup's USED bit is unset, the page * will not be added to any memcg's LRU. If page_cgroup's USED bit is * set, the commit after this will fail, anyway. * This all charge/uncharge is done under some mutual execustion. * So, we don't need to taking care of changes in USED bit. */ if (likely(!PageLRU(page))) return; spin_lock_irqsave(&zone->lru_lock, flags); lru = page_lru(page); /* * The uncharged page could still be registered to the LRU of * the stale pc->mem_cgroup. * * As pc->mem_cgroup is about to get overwritten, the old LRU * accounting needs to be taken care of. Let root_mem_cgroup * babysit the page until the new memcg is responsible for it. * * The PCG_USED bit is guarded by lock_page() as the page is * swapcache/pagecache. */ if (PageLRU(page) && PageCgroupAcctLRU(pc) && !PageCgroupUsed(pc)) { del_page_from_lru_list(zone, page, lru); add_page_to_lru_list(zone, page, lru); } spin_unlock_irqrestore(&zone->lru_lock, flags); } static void mem_cgroup_lru_add_after_commit(struct page *page) { enum lru_list lru; unsigned long flags; struct zone *zone = page_zone(page); struct page_cgroup *pc = lookup_page_cgroup(page); /* * putback: charge: * SetPageLRU SetPageCgroupUsed * smp_mb smp_mb * PageCgroupUsed && add to memcg LRU PageLRU && add to memcg LRU * * Ensure that one of the two sides adds the page to the memcg * LRU during a race. */ smp_mb(); /* taking care of that the page is added to LRU while we commit it */ if (likely(!PageLRU(page))) return; spin_lock_irqsave(&zone->lru_lock, flags); lru = page_lru(page); /* * If the page is not on the LRU, someone will soon put it * there. If it is, and also already accounted for on the * memcg-side, it must be on the right lruvec as setting * pc->mem_cgroup and PageCgroupUsed is properly ordered. * Otherwise, root_mem_cgroup has been babysitting the page * during the charge. Move it to the new memcg now. */ if (PageLRU(page) && !PageCgroupAcctLRU(pc)) { del_page_from_lru_list(zone, page, lru); add_page_to_lru_list(zone, page, lru); } spin_unlock_irqrestore(&zone->lru_lock, flags); } /* * Checks whether given mem is same or in the root_mem_cgroup's * hierarchy subtree */ static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, struct mem_cgroup *memcg) { if (root_memcg != memcg) { return (root_memcg->use_hierarchy && css_is_ancestor(&memcg->css, &root_memcg->css)); } return true; } int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg) { int ret; struct mem_cgroup *curr = NULL; struct task_struct *p; p = find_lock_task_mm(task); if (!p) return 0; curr = try_get_mem_cgroup_from_mm(p->mm); task_unlock(p); if (!curr) return 0; /* * We should check use_hierarchy of "memcg" not "curr". Because checking * use_hierarchy of "curr" here make this function true if hierarchy is * enabled in "curr" and "curr" is a child of "memcg" in *cgroup* * hierarchy(even if use_hierarchy is disabled in "memcg"). */ ret = mem_cgroup_same_or_subtree(memcg, curr); css_put(&curr->css); return ret; } int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg, struct zone *zone) { unsigned long inactive_ratio; int nid = zone_to_nid(zone); int zid = zone_idx(zone); unsigned long inactive; unsigned long active; unsigned long gb; inactive = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, BIT(LRU_INACTIVE_ANON)); active = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, BIT(LRU_ACTIVE_ANON)); gb = (inactive + active) >> (30 - PAGE_SHIFT); if (gb) inactive_ratio = int_sqrt(10 * gb); else inactive_ratio = 1; return inactive * inactive_ratio < active; } int mem_cgroup_inactive_file_is_low(struct mem_cgroup *memcg, struct zone *zone) { unsigned long active; unsigned long inactive; int zid = zone_idx(zone); int nid = zone_to_nid(zone); inactive = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, BIT(LRU_INACTIVE_FILE)); active = mem_cgroup_zone_nr_lru_pages(memcg, nid, zid, BIT(LRU_ACTIVE_FILE)); return (active > inactive); } struct zone_reclaim_stat *mem_cgroup_get_reclaim_stat(struct mem_cgroup *memcg, struct zone *zone) { int nid = zone_to_nid(zone); int zid = zone_idx(zone); struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(memcg, nid, zid); return &mz->reclaim_stat; } struct zone_reclaim_stat * mem_cgroup_get_reclaim_stat_from_page(struct page *page) { struct page_cgroup *pc; struct mem_cgroup_per_zone *mz; if (mem_cgroup_disabled()) return NULL; pc = lookup_page_cgroup(page); if (!PageCgroupUsed(pc)) return NULL; /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ smp_rmb(); mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); return &mz->reclaim_stat; } #define mem_cgroup_from_res_counter(counter, member) \ container_of(counter, struct mem_cgroup, member) /** * mem_cgroup_margin - calculate chargeable space of a memory cgroup * @mem: the memory cgroup * * Returns the maximum amount of memory @mem can be charged with, in * pages. */ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) { unsigned long long margin; margin = res_counter_margin(&memcg->res); if (do_swap_account) margin = min(margin, res_counter_margin(&memcg->memsw)); return margin >> PAGE_SHIFT; } int mem_cgroup_swappiness(struct mem_cgroup *memcg) { struct cgroup *cgrp = memcg->css.cgroup; /* root ? */ if (cgrp->parent == NULL) return vm_swappiness; return memcg->swappiness; } static void mem_cgroup_start_move(struct mem_cgroup *memcg) { int cpu; get_online_cpus(); spin_lock(&memcg->pcp_counter_lock); for_each_online_cpu(cpu) per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) += 1; memcg->nocpu_base.count[MEM_CGROUP_ON_MOVE] += 1; spin_unlock(&memcg->pcp_counter_lock); put_online_cpus(); synchronize_rcu(); } static void mem_cgroup_end_move(struct mem_cgroup *memcg) { int cpu; if (!memcg) return; get_online_cpus(); spin_lock(&memcg->pcp_counter_lock); for_each_online_cpu(cpu) per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) -= 1; memcg->nocpu_base.count[MEM_CGROUP_ON_MOVE] -= 1; spin_unlock(&memcg->pcp_counter_lock); put_online_cpus(); } /* * 2 routines for checking "mem" is under move_account() or not. * * mem_cgroup_stealed() - checking a cgroup is mc.from or not. This is used * for avoiding race in accounting. If true, * pc->mem_cgroup may be overwritten. * * mem_cgroup_under_move() - checking a cgroup is mc.from or mc.to or * under hierarchy of moving cgroups. This is for * waiting at hith-memory prressure caused by "move". */ static bool mem_cgroup_stealed(struct mem_cgroup *memcg) { VM_BUG_ON(!rcu_read_lock_held()); return this_cpu_read(memcg->stat->count[MEM_CGROUP_ON_MOVE]) > 0; } static bool mem_cgroup_under_move(struct mem_cgroup *memcg) { struct mem_cgroup *from; struct mem_cgroup *to; bool ret = false; /* * Unlike task_move routines, we access mc.to, mc.from not under * mutual exclusion by cgroup_mutex. Here, we take spinlock instead. */ spin_lock(&mc.lock); from = mc.from; to = mc.to; if (!from) goto unlock; ret = mem_cgroup_same_or_subtree(memcg, from) || mem_cgroup_same_or_subtree(memcg, to); unlock: spin_unlock(&mc.lock); return ret; } static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) { if (mc.moving_task && current != mc.moving_task) { if (mem_cgroup_under_move(memcg)) { DEFINE_WAIT(wait); prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE); /* moving charge context might have finished. */ if (mc.moving_task) schedule(); finish_wait(&mc.waitq, &wait); return true; } } return false; } /** * mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode. * @memcg: The memory cgroup that went over limit * @p: Task that is going to be killed * * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is * enabled */ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) { struct cgroup *task_cgrp; struct cgroup *mem_cgrp; /* * Need a buffer in BSS, can't rely on allocations. The code relies * on the assumption that OOM is serialized for memory controller. * If this assumption is broken, revisit this code. */ static char memcg_name[PATH_MAX]; int ret; if (!memcg || !p) return; rcu_read_lock(); mem_cgrp = memcg->css.cgroup; task_cgrp = task_cgroup(p, mem_cgroup_subsys_id); ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX); if (ret < 0) { /* * Unfortunately, we are unable to convert to a useful name * But we'll still print out the usage information */ rcu_read_unlock(); goto done; } rcu_read_unlock(); printk(KERN_INFO "Task in %s killed", memcg_name); rcu_read_lock(); ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX); if (ret < 0) { rcu_read_unlock(); goto done; } rcu_read_unlock(); /* * Continues from above, so we don't need an KERN_ level */ printk(KERN_CONT " as a result of limit of %s\n", memcg_name); done: printk(KERN_INFO "memory: usage %llukB, limit %llukB, failcnt %llu\n", res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, res_counter_read_u64(&memcg->res, RES_FAILCNT)); printk(KERN_INFO "memory+swap: usage %llukB, limit %llukB, " "failcnt %llu\n", res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); } /* * This function returns the number of memcg under hierarchy tree. Returns * 1(self count) if no children. */ static int mem_cgroup_count_children(struct mem_cgroup *memcg) { int num = 0; struct mem_cgroup *iter; for_each_mem_cgroup_tree(iter, memcg) num++; return num; } /* * Return the memory (and swap, if configured) limit for a memcg. */ u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) { u64 limit; u64 memsw; limit = res_counter_read_u64(&memcg->res, RES_LIMIT); limit += total_swap_pages << PAGE_SHIFT; memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); /* * If memsw is finite and limits the amount of swap space available * to this memcg, return that limit. */ return min(limit, memsw); } static unsigned long mem_cgroup_reclaim(struct mem_cgroup *memcg, gfp_t gfp_mask, unsigned long flags) { unsigned long total = 0; bool noswap = false; int loop; if (flags & MEM_CGROUP_RECLAIM_NOSWAP) noswap = true; if (!(flags & MEM_CGROUP_RECLAIM_SHRINK) && memcg->memsw_is_minimum) noswap = true; for (loop = 0; loop < MEM_CGROUP_MAX_RECLAIM_LOOPS; loop++) { if (loop) drain_all_stock_async(memcg); total += try_to_free_mem_cgroup_pages(memcg, gfp_mask, noswap); /* * Allow limit shrinkers, which are triggered directly * by userspace, to catch signals and stop reclaim * after minimal progress, regardless of the margin. */ if (total && (flags & MEM_CGROUP_RECLAIM_SHRINK)) break; if (mem_cgroup_margin(memcg)) break; /* * If nothing was reclaimed after two attempts, there * may be no reclaimable pages in this hierarchy. */ if (loop && !total) break; } return total; } /** * test_mem_cgroup_node_reclaimable * @mem: the target memcg * @nid: the node ID to be checked. * @noswap : specify true here if the user wants flle only information. * * This function returns whether the specified memcg contains any * reclaimable pages on a node. Returns true if there are any reclaimable * pages in the node. */ static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *memcg, int nid, bool noswap) { if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_FILE)) return true; if (noswap || !total_swap_pages) return false; if (mem_cgroup_node_nr_lru_pages(memcg, nid, LRU_ALL_ANON)) return true; return false; } #if MAX_NUMNODES > 1 /* * Always updating the nodemask is not very good - even if we have an empty * list or the wrong list here, we can start from some node and traverse all * nodes based on the zonelist. So update the list loosely once per 10 secs. * */ static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg) { int nid; /* * numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET * pagein/pageout changes since the last update. */ if (!atomic_read(&memcg->numainfo_events)) return; if (atomic_inc_return(&memcg->numainfo_updating) > 1) return; /* make a nodemask where this memcg uses memory from */ memcg->scan_nodes = node_states[N_HIGH_MEMORY]; for_each_node_mask(nid, node_states[N_HIGH_MEMORY]) { if (!test_mem_cgroup_node_reclaimable(memcg, nid, false)) node_clear(nid, memcg->scan_nodes); } atomic_set(&memcg->numainfo_events, 0); atomic_set(&memcg->numainfo_updating, 0); } /* * Selecting a node where we start reclaim from. Because what we need is just * reducing usage counter, start from anywhere is O,K. Considering * memory reclaim from current node, there are pros. and cons. * * Freeing memory from current node means freeing memory from a node which * we'll use or we've used. So, it may make LRU bad. And if several threads * hit limits, it will see a contention on a node. But freeing from remote * node means more costs for memory reclaim because of memory latency. * * Now, we use round-robin. Better algorithm is welcomed. */ int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) { int node; mem_cgroup_may_update_nodemask(memcg); node = memcg->last_scanned_node; node = next_node(node, memcg->scan_nodes); if (node == MAX_NUMNODES) node = first_node(memcg->scan_nodes); /* * We call this when we hit limit, not when pages are added to LRU. * No LRU may hold pages because all pages are UNEVICTABLE or * memcg is too small and all pages are not on LRU. In that case, * we use curret node. */ if (unlikely(node == MAX_NUMNODES)) node = numa_node_id(); memcg->last_scanned_node = node; return node; } /* * Check all nodes whether it contains reclaimable pages or not. * For quick scan, we make use of scan_nodes. This will allow us to skip * unused nodes. But scan_nodes is lazily updated and may not cotain * enough new information. We need to do double check. */ bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) { int nid; /* * quick check...making use of scan_node. * We can skip unused nodes. */ if (!nodes_empty(memcg->scan_nodes)) { for (nid = first_node(memcg->scan_nodes); nid < MAX_NUMNODES; nid = next_node(nid, memcg->scan_nodes)) { if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) return true; } } /* * Check rest of nodes. */ for_each_node_state(nid, N_HIGH_MEMORY) { if (node_isset(nid, memcg->scan_nodes)) continue; if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) return true; } return false; } #else int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) { return 0; } bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) { return test_mem_cgroup_node_reclaimable(memcg, 0, noswap); } #endif static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, struct zone *zone, gfp_t gfp_mask, unsigned long *total_scanned) { struct mem_cgroup *victim = NULL; int total = 0; int loop = 0; unsigned long excess; unsigned long nr_scanned; struct mem_cgroup_reclaim_cookie reclaim = { .zone = zone, .priority = 0, }; excess = res_counter_soft_limit_excess(&root_memcg->res) >> PAGE_SHIFT; while (1) { victim = mem_cgroup_iter(root_memcg, victim, &reclaim); if (!victim) { loop++; if (loop >= 2) { /* * If we have not been able to reclaim * anything, it might because there are * no reclaimable pages under this hierarchy */ if (!total) break; /* * We want to do more targeted reclaim. * excess >> 2 is not to excessive so as to * reclaim too much, nor too less that we keep * coming back to reclaim from this cgroup */ if (total >= (excess >> 2) || (loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) break; } continue; } if (!mem_cgroup_reclaimable(victim, false)) continue; total += mem_cgroup_shrink_node_zone(victim, gfp_mask, false, zone, &nr_scanned); *total_scanned += nr_scanned; if (!res_counter_soft_limit_excess(&root_memcg->res)) break; } mem_cgroup_iter_break(root_memcg, victim); return total; } /* * Check OOM-Killer is already running under our hierarchy. * If someone is running, return false. * Has to be called with memcg_oom_lock */ static bool mem_cgroup_oom_lock(struct mem_cgroup *memcg) { struct mem_cgroup *iter, *failed = NULL; for_each_mem_cgroup_tree(iter, memcg) { if (iter->oom_lock) { /* * this subtree of our hierarchy is already locked * so we cannot give a lock. */ failed = iter; mem_cgroup_iter_break(memcg, iter); break; } else iter->oom_lock = true; } if (!failed) return true; /* * OK, we failed to lock the whole subtree so we have to clean up * what we set up to the failing subtree */ for_each_mem_cgroup_tree(iter, memcg) { if (iter == failed) { mem_cgroup_iter_break(memcg, iter); break; } iter->oom_lock = false; } return false; } /* * Has to be called with memcg_oom_lock */ static int mem_cgroup_oom_unlock(struct mem_cgroup *memcg) { struct mem_cgroup *iter; for_each_mem_cgroup_tree(iter, memcg) iter->oom_lock = false; return 0; } static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg) { struct mem_cgroup *iter; for_each_mem_cgroup_tree(iter, memcg) atomic_inc(&iter->under_oom); } static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg) { struct mem_cgroup *iter; /* * When a new child is created while the hierarchy is under oom, * mem_cgroup_oom_lock() may not be called. We have to use * atomic_add_unless() here. */ for_each_mem_cgroup_tree(iter, memcg) atomic_add_unless(&iter->under_oom, -1, 0); } static DEFINE_SPINLOCK(memcg_oom_lock); static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq); struct oom_wait_info { struct mem_cgroup *mem; wait_queue_t wait; }; static int memcg_oom_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *arg) { struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg, *oom_wait_memcg; struct oom_wait_info *oom_wait_info; oom_wait_info = container_of(wait, struct oom_wait_info, wait); oom_wait_memcg = oom_wait_info->mem; /* * Both of oom_wait_info->mem and wake_mem are stable under us. * Then we can use css_is_ancestor without taking care of RCU. */ if (!mem_cgroup_same_or_subtree(oom_wait_memcg, wake_memcg) && !mem_cgroup_same_or_subtree(wake_memcg, oom_wait_memcg)) return 0; return autoremove_wake_function(wait, mode, sync, arg); } static void memcg_wakeup_oom(struct mem_cgroup *memcg) { /* for filtering, pass "memcg" as argument. */ __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg); } static void memcg_oom_recover(struct mem_cgroup *memcg) { if (memcg && atomic_read(&memcg->under_oom)) memcg_wakeup_oom(memcg); } /* * try to call OOM killer. returns false if we should exit memory-reclaim loop. */ bool mem_cgroup_handle_oom(struct mem_cgroup *memcg, gfp_t mask) { struct oom_wait_info owait; bool locked, need_to_kill; owait.mem = memcg; owait.wait.flags = 0; owait.wait.func = memcg_oom_wake_function; owait.wait.private = current; INIT_LIST_HEAD(&owait.wait.task_list); need_to_kill = true; mem_cgroup_mark_under_oom(memcg); /* At first, try to OOM lock hierarchy under memcg.*/ spin_lock(&memcg_oom_lock); locked = mem_cgroup_oom_lock(memcg); /* * Even if signal_pending(), we can't quit charge() loop without * accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL * under OOM is always welcomed, use TASK_KILLABLE here. */ prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE); if (!locked || memcg->oom_kill_disable) need_to_kill = false; if (locked) mem_cgroup_oom_notify(memcg); spin_unlock(&memcg_oom_lock); if (need_to_kill) { finish_wait(&memcg_oom_waitq, &owait.wait); mem_cgroup_out_of_memory(memcg, mask); } else { schedule(); finish_wait(&memcg_oom_waitq, &owait.wait); } spin_lock(&memcg_oom_lock); if (locked) mem_cgroup_oom_unlock(memcg); memcg_wakeup_oom(memcg); spin_unlock(&memcg_oom_lock); mem_cgroup_unmark_under_oom(memcg); if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current)) return false; /* Give chance to dying process */ schedule_timeout_uninterruptible(1); return true; } /* * Currently used to update mapped file statistics, but the routine can be * generalized to update other statistics as well. * * Notes: Race condition * * We usually use page_cgroup_lock() for accessing page_cgroup member but * it tends to be costly. But considering some conditions, we doesn't need * to do so _always_. * * Considering "charge", lock_page_cgroup() is not required because all * file-stat operations happen after a page is attached to radix-tree. There * are no race with "charge". * * Considering "uncharge", we know that memcg doesn't clear pc->mem_cgroup * at "uncharge" intentionally. So, we always see valid pc->mem_cgroup even * if there are race with "uncharge". Statistics itself is properly handled * by flags. * * Considering "move", this is an only case we see a race. To make the race * small, we check MEM_CGROUP_ON_MOVE percpu value and detect there are * possibility of race condition. If there is, we take a lock. */ void mem_cgroup_update_page_stat(struct page *page, enum mem_cgroup_page_stat_item idx, int val) { struct mem_cgroup *memcg; struct page_cgroup *pc = lookup_page_cgroup(page); bool need_unlock = false; unsigned long uninitialized_var(flags); if (mem_cgroup_disabled()) return; rcu_read_lock(); memcg = pc->mem_cgroup; if (unlikely(!memcg || !PageCgroupUsed(pc))) goto out; /* pc->mem_cgroup is unstable ? */ if (unlikely(mem_cgroup_stealed(memcg)) || PageTransHuge(page)) { /* take a lock against to access pc->mem_cgroup */ move_lock_page_cgroup(pc, &flags); need_unlock = true; memcg = pc->mem_cgroup; if (!memcg || !PageCgroupUsed(pc)) goto out; } switch (idx) { case MEMCG_NR_FILE_MAPPED: if (val > 0) SetPageCgroupFileMapped(pc); else if (!page_mapped(page)) ClearPageCgroupFileMapped(pc); idx = MEM_CGROUP_STAT_FILE_MAPPED; break; default: BUG(); } this_cpu_add(memcg->stat->count[idx], val); out: if (unlikely(need_unlock)) move_unlock_page_cgroup(pc, &flags); rcu_read_unlock(); return; } EXPORT_SYMBOL(mem_cgroup_update_page_stat); /* * size of first charge trial. "32" comes from vmscan.c's magic value. * TODO: maybe necessary to use big numbers in big irons. */ #define CHARGE_BATCH 32U struct memcg_stock_pcp { struct mem_cgroup *cached; /* this never be root cgroup */ unsigned int nr_pages; struct work_struct work; unsigned long flags; #define FLUSHING_CACHED_CHARGE (0) }; static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); static DEFINE_MUTEX(percpu_charge_mutex); /* * Try to consume stocked charge on this cpu. If success, one page is consumed * from local stock and true is returned. If the stock is 0 or charges from a * cgroup which is not current target, returns false. This stock will be * refilled. */ static bool consume_stock(struct mem_cgroup *memcg) { struct memcg_stock_pcp *stock; bool ret = true; stock = &get_cpu_var(memcg_stock); if (memcg == stock->cached && stock->nr_pages) stock->nr_pages--; else /* need to call res_counter_charge */ ret = false; put_cpu_var(memcg_stock); return ret; } /* * Returns stocks cached in percpu to res_counter and reset cached information. */ static void drain_stock(struct memcg_stock_pcp *stock) { struct mem_cgroup *old = stock->cached; if (stock->nr_pages) { unsigned long bytes = stock->nr_pages * PAGE_SIZE; res_counter_uncharge(&old->res, bytes); if (do_swap_account) res_counter_uncharge(&old->memsw, bytes); stock->nr_pages = 0; } stock->cached = NULL; } /* * This must be called under preempt disabled or must be called by * a thread which is pinned to local cpu. */ static void drain_local_stock(struct work_struct *dummy) { struct memcg_stock_pcp *stock = &__get_cpu_var(memcg_stock); drain_stock(stock); clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); } /* * Cache charges(val) which is from res_counter, to local per_cpu area. * This will be consumed by consume_stock() function, later. */ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) { struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); if (stock->cached != memcg) { /* reset if necessary */ drain_stock(stock); stock->cached = memcg; } stock->nr_pages += nr_pages; put_cpu_var(memcg_stock); } /* * Drains all per-CPU charge caches for given root_memcg resp. subtree * of the hierarchy under it. sync flag says whether we should block * until the work is done. */ static void drain_all_stock(struct mem_cgroup *root_memcg, bool sync) { int cpu, curcpu; /* Notify other cpus that system-wide "drain" is running */ get_online_cpus(); curcpu = get_cpu(); for_each_online_cpu(cpu) { struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); struct mem_cgroup *memcg; memcg = stock->cached; if (!memcg || !stock->nr_pages) continue; if (!mem_cgroup_same_or_subtree(root_memcg, memcg)) continue; if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { if (cpu == curcpu) drain_local_stock(&stock->work); else schedule_work_on(cpu, &stock->work); } } put_cpu(); if (!sync) goto out; for_each_online_cpu(cpu) { struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); if (test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) flush_work(&stock->work); } out: put_online_cpus(); } /* * Tries to drain stocked charges in other cpus. This function is asynchronous * and just put a work per cpu for draining localy on each cpu. Caller can * expects some charges will be back to res_counter later but cannot wait for * it. */ static void drain_all_stock_async(struct mem_cgroup *root_memcg) { /* * If someone calls draining, avoid adding more kworker runs. */ if (!mutex_trylock(&percpu_charge_mutex)) return; drain_all_stock(root_memcg, false); mutex_unlock(&percpu_charge_mutex); } /* This is a synchronous drain interface. */ static void drain_all_stock_sync(struct mem_cgroup *root_memcg) { /* called when force_empty is called */ mutex_lock(&percpu_charge_mutex); drain_all_stock(root_memcg, true); mutex_unlock(&percpu_charge_mutex); } /* * This function drains percpu counter value from DEAD cpu and * move it to local cpu. Note that this function can be preempted. */ static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *memcg, int cpu) { int i; spin_lock(&memcg->pcp_counter_lock); for (i = 0; i < MEM_CGROUP_STAT_DATA; i++) { long x = per_cpu(memcg->stat->count[i], cpu); per_cpu(memcg->stat->count[i], cpu) = 0; memcg->nocpu_base.count[i] += x; } for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) { unsigned long x = per_cpu(memcg->stat->events[i], cpu); per_cpu(memcg->stat->events[i], cpu) = 0; memcg->nocpu_base.events[i] += x; } /* need to clear ON_MOVE value, works as a kind of lock. */ per_cpu(memcg->stat->count[MEM_CGROUP_ON_MOVE], cpu) = 0; spin_unlock(&memcg->pcp_counter_lock); } static void synchronize_mem_cgroup_on_move(struct mem_cgroup *memcg, int cpu) { int idx = MEM_CGROUP_ON_MOVE; spin_lock(&memcg->pcp_counter_lock); per_cpu(memcg->stat->count[idx], cpu) = memcg->nocpu_base.count[idx]; spin_unlock(&memcg->pcp_counter_lock); } static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, unsigned long action, void *hcpu) { int cpu = (unsigned long)hcpu; struct memcg_stock_pcp *stock; struct mem_cgroup *iter; if ((action == CPU_ONLINE)) { for_each_mem_cgroup(iter) synchronize_mem_cgroup_on_move(iter, cpu); return NOTIFY_OK; } if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) return NOTIFY_OK; for_each_mem_cgroup(iter) mem_cgroup_drain_pcp_counter(iter, cpu); stock = &per_cpu(memcg_stock, cpu); drain_stock(stock); return NOTIFY_OK; } /* See __mem_cgroup_try_charge() for details */ enum { CHARGE_OK, /* success */ CHARGE_RETRY, /* need to retry but retry is not bad */ CHARGE_NOMEM, /* we can't do more. return -ENOMEM */ CHARGE_WOULDBLOCK, /* GFP_WAIT wasn't set and no enough res. */ CHARGE_OOM_DIE, /* the current is killed because of OOM */ }; static int mem_cgroup_do_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, unsigned int nr_pages, bool oom_check) { unsigned long csize = nr_pages * PAGE_SIZE; struct mem_cgroup *mem_over_limit; struct res_counter *fail_res; unsigned long flags = 0; int ret; ret = res_counter_charge(&memcg->res, csize, &fail_res); if (likely(!ret)) { if (!do_swap_account) return CHARGE_OK; ret = res_counter_charge(&memcg->memsw, csize, &fail_res); if (likely(!ret)) return CHARGE_OK; res_counter_uncharge(&memcg->res, csize); mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); flags |= MEM_CGROUP_RECLAIM_NOSWAP; } else mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); /* * nr_pages can be either a huge page (HPAGE_PMD_NR), a batch * of regular pages (CHARGE_BATCH), or a single regular page (1). * * Never reclaim on behalf of optional batching, retry with a * single page instead. */ if (nr_pages == CHARGE_BATCH) return CHARGE_RETRY; if (!(gfp_mask & __GFP_WAIT)) return CHARGE_WOULDBLOCK; ret = mem_cgroup_reclaim(mem_over_limit, gfp_mask, flags); if (mem_cgroup_margin(mem_over_limit) >= nr_pages) return CHARGE_RETRY; /* * Even though the limit is exceeded at this point, reclaim * may have been able to free some pages. Retry the charge * before killing the task. * * Only for regular pages, though: huge pages are rather * unlikely to succeed so close to the limit, and we fall back * to regular pages anyway in case of failure. */ if (nr_pages == 1 && ret) return CHARGE_RETRY; /* * At task move, charge accounts can be doubly counted. So, it's * better to wait until the end of task_move if something is going on. */ if (mem_cgroup_wait_acct_move(mem_over_limit)) return CHARGE_RETRY; /* If we don't need to call oom-killer at el, return immediately */ if (!oom_check) return CHARGE_NOMEM; /* check OOM */ if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask)) return CHARGE_OOM_DIE; return CHARGE_RETRY; } /* * Unlike exported interface, "oom" parameter is added. if oom==true, * oom-killer can be invoked. */ static int __mem_cgroup_try_charge(struct mm_struct *mm, gfp_t gfp_mask, unsigned int nr_pages, struct mem_cgroup **ptr, bool oom) { unsigned int batch = max(CHARGE_BATCH, nr_pages); int nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; struct mem_cgroup *memcg = NULL; int ret; /* * Unlike gloval-vm's OOM-kill, we're not in memory shortage * in system level. So, allow to go ahead dying process in addition to * MEMDIE process. */ if (unlikely(test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current))) goto bypass; /* * We always charge the cgroup the mm_struct belongs to. * The mm_struct's mem_cgroup changes on task migration if the * thread group leader migrates. It's possible that mm is not * set, if so charge the init_mm (happens for pagecache usage). */ if (!*ptr && !mm) goto bypass; again: if (*ptr) { /* css should be a valid one */ memcg = *ptr; VM_BUG_ON(css_is_removed(&memcg->css)); if (mem_cgroup_is_root(memcg)) goto done; if (nr_pages == 1 && consume_stock(memcg)) goto done; css_get(&memcg->css); } else { struct task_struct *p; rcu_read_lock(); p = rcu_dereference(mm->owner); /* * Because we don't have task_lock(), "p" can exit. * In that case, "memcg" can point to root or p can be NULL with * race with swapoff. Then, we have small risk of mis-accouning. * But such kind of mis-account by race always happens because * we don't have cgroup_mutex(). It's overkill and we allo that * small race, here. * (*) swapoff at el will charge against mm-struct not against * task-struct. So, mm->owner can be NULL. */ memcg = mem_cgroup_from_task(p); if (!memcg || mem_cgroup_is_root(memcg)) { rcu_read_unlock(); goto done; } if (nr_pages == 1 && consume_stock(memcg)) { /* * It seems dagerous to access memcg without css_get(). * But considering how consume_stok works, it's not * necessary. If consume_stock success, some charges * from this memcg are cached on this cpu. So, we * don't need to call css_get()/css_tryget() before * calling consume_stock(). */ rcu_read_unlock(); goto done; } /* after here, we may be blocked. we need to get refcnt */ if (!css_tryget(&memcg->css)) { rcu_read_unlock(); goto again; } rcu_read_unlock(); } do { bool oom_check; /* If killed, bypass charge */ if (fatal_signal_pending(current)) { css_put(&memcg->css); goto bypass; } oom_check = false; if (oom && !nr_oom_retries) { oom_check = true; nr_oom_retries = MEM_CGROUP_RECLAIM_RETRIES; } ret = mem_cgroup_do_charge(memcg, gfp_mask, batch, oom_check); switch (ret) { case CHARGE_OK: break; case CHARGE_RETRY: /* not in OOM situation but retry */ batch = nr_pages; css_put(&memcg->css); memcg = NULL; goto again; case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */ css_put(&memcg->css); goto nomem; case CHARGE_NOMEM: /* OOM routine works */ if (!oom) { css_put(&memcg->css); goto nomem; } /* If oom, we never return -ENOMEM */ nr_oom_retries--; break; case CHARGE_OOM_DIE: /* Killed by OOM Killer */ css_put(&memcg->css); goto bypass; } } while (ret != CHARGE_OK); if (batch > nr_pages) refill_stock(memcg, batch - nr_pages); css_put(&memcg->css); done: *ptr = memcg; return 0; nomem: *ptr = NULL; return -ENOMEM; bypass: *ptr = NULL; return 0; } /* * Somemtimes we have to undo a charge we got by try_charge(). * This function is for that and do uncharge, put css's refcnt. * gotten by try_charge(). */ static void __mem_cgroup_cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) { if (!mem_cgroup_is_root(memcg)) { unsigned long bytes = nr_pages * PAGE_SIZE; res_counter_uncharge(&memcg->res, bytes); if (do_swap_account) res_counter_uncharge(&memcg->memsw, bytes); } } /* * A helper function to get mem_cgroup from ID. must be called under * rcu_read_lock(). The caller must check css_is_removed() or some if * it's concern. (dropping refcnt from swap can be called against removed * memcg.) */ static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) { struct cgroup_subsys_state *css; /* ID 0 is unused ID */ if (!id) return NULL; css = css_lookup(&mem_cgroup_subsys, id); if (!css) return NULL; return container_of(css, struct mem_cgroup, css); } struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) { struct mem_cgroup *memcg = NULL; struct page_cgroup *pc; unsigned short id; swp_entry_t ent; VM_BUG_ON(!PageLocked(page)); pc = lookup_page_cgroup(page); lock_page_cgroup(pc); if (PageCgroupUsed(pc)) { memcg = pc->mem_cgroup; if (memcg && !css_tryget(&memcg->css)) memcg = NULL; } else if (PageSwapCache(page)) { ent.val = page_private(page); id = lookup_swap_cgroup(ent); rcu_read_lock(); memcg = mem_cgroup_lookup(id); if (memcg && !css_tryget(&memcg->css)) memcg = NULL; rcu_read_unlock(); } unlock_page_cgroup(pc); return memcg; } static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, struct page *page, unsigned int nr_pages, struct page_cgroup *pc, enum charge_type ctype) { lock_page_cgroup(pc); if (unlikely(PageCgroupUsed(pc))) { unlock_page_cgroup(pc); __mem_cgroup_cancel_charge(memcg, nr_pages); return; } /* * we don't need page_cgroup_lock about tail pages, becase they are not * accessed by any other context at this point. */ pc->mem_cgroup = memcg; /* * We access a page_cgroup asynchronously without lock_page_cgroup(). * Especially when a page_cgroup is taken from a page, pc->mem_cgroup * is accessed after testing USED bit. To make pc->mem_cgroup visible * before USED bit, we need memory barrier here. * See mem_cgroup_add_lru_list(), etc. */ smp_wmb(); switch (ctype) { case MEM_CGROUP_CHARGE_TYPE_CACHE: case MEM_CGROUP_CHARGE_TYPE_SHMEM: SetPageCgroupCache(pc); SetPageCgroupUsed(pc); break; case MEM_CGROUP_CHARGE_TYPE_MAPPED: ClearPageCgroupCache(pc); SetPageCgroupUsed(pc); break; default: break; } mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), nr_pages); unlock_page_cgroup(pc); /* * "charge_statistics" updated event counter. Then, check it. * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. * if they exceeds softlimit. */ memcg_check_events(memcg, page); } #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) | (1 << PCG_MOVE_LOCK) |\ (1 << PCG_ACCT_LRU) | (1 << PCG_MIGRATION)) /* * Because tail pages are not marked as "used", set it. We're under * zone->lru_lock, 'splitting on pmd' and compound_lock. * charge/uncharge will be never happen and move_account() is done under * compound_lock(), so we don't have to take care of races. */ void mem_cgroup_split_huge_fixup(struct page *head) { struct page_cgroup *head_pc = lookup_page_cgroup(head); struct page_cgroup *pc; int i; if (mem_cgroup_disabled()) return; for (i = 1; i < HPAGE_PMD_NR; i++) { pc = head_pc + i; pc->mem_cgroup = head_pc->mem_cgroup; smp_wmb();/* see __commit_charge() */ /* * LRU flags cannot be copied because we need to add tail * page to LRU by generic call and our hooks will be called. */ pc->flags = head_pc->flags & ~PCGF_NOCOPY_AT_SPLIT; } if (PageCgroupAcctLRU(head_pc)) { enum lru_list lru; struct mem_cgroup_per_zone *mz; /* * We hold lru_lock, then, reduce counter directly. */ lru = page_lru(head); mz = page_cgroup_zoneinfo(head_pc->mem_cgroup, head); MEM_CGROUP_ZSTAT(mz, lru) -= HPAGE_PMD_NR - 1; } } #endif /** * mem_cgroup_move_account - move account of the page * @page: the page * @nr_pages: number of regular pages (>1 for huge pages) * @pc: page_cgroup of the page. * @from: mem_cgroup which the page is moved from. * @to: mem_cgroup which the page is moved to. @from != @to. * @uncharge: whether we should call uncharge and css_put against @from. * * The caller must confirm following. * - page is not on LRU (isolate_page() is useful.) * - compound_lock is held when nr_pages > 1 * * This function doesn't do "charge" nor css_get to new cgroup. It should be * done by a caller(__mem_cgroup_try_charge would be useful). If @uncharge is * true, this function does "uncharge" from old cgroup, but it doesn't if * @uncharge is false, so a caller should do "uncharge". */ static int mem_cgroup_move_account(struct page *page, unsigned int nr_pages, struct page_cgroup *pc, struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge) { unsigned long flags; int ret; VM_BUG_ON(from == to); VM_BUG_ON(PageLRU(page)); /* * The page is isolated from LRU. So, collapse function * will not handle this page. But page splitting can happen. * Do this check under compound_page_lock(). The caller should * hold it. */ ret = -EBUSY; if (nr_pages > 1 && !PageTransHuge(page)) goto out; lock_page_cgroup(pc); ret = -EINVAL; if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) goto unlock; move_lock_page_cgroup(pc, &flags); if (PageCgroupFileMapped(pc)) { /* Update mapped_file data for mem_cgroup */ preempt_disable(); __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); preempt_enable(); } mem_cgroup_charge_statistics(from, PageCgroupCache(pc), -nr_pages); if (uncharge) /* This is not "cancel", but cancel_charge does all we need. */ __mem_cgroup_cancel_charge(from, nr_pages); /* caller should have done css_get */ pc->mem_cgroup = to; mem_cgroup_charge_statistics(to, PageCgroupCache(pc), nr_pages); /* * We charges against "to" which may not have any tasks. Then, "to" * can be under rmdir(). But in current implementation, caller of * this function is just force_empty() and move charge, so it's * guaranteed that "to" is never removed. So, we don't check rmdir * status here. */ move_unlock_page_cgroup(pc, &flags); ret = 0; unlock: unlock_page_cgroup(pc); /* * check events */ memcg_check_events(to, page); memcg_check_events(from, page); out: return ret; } /* * move charges to its parent. */ static int mem_cgroup_move_parent(struct page *page, struct page_cgroup *pc, struct mem_cgroup *child, gfp_t gfp_mask) { struct cgroup *cg = child->css.cgroup; struct cgroup *pcg = cg->parent; struct mem_cgroup *parent; unsigned int nr_pages; unsigned long uninitialized_var(flags); int ret; /* Is ROOT ? */ if (!pcg) return -EINVAL; ret = -EBUSY; if (!get_page_unless_zero(page)) goto out; if (isolate_lru_page(page)) goto put; nr_pages = hpage_nr_pages(page); parent = mem_cgroup_from_cont(pcg); ret = __mem_cgroup_try_charge(NULL, gfp_mask, nr_pages, &parent, false); if (ret || !parent) goto put_back; if (nr_pages > 1) flags = compound_lock_irqsave(page); ret = mem_cgroup_move_account(page, nr_pages, pc, child, parent, true); if (ret) __mem_cgroup_cancel_charge(parent, nr_pages); if (nr_pages > 1) compound_unlock_irqrestore(page, flags); put_back: putback_lru_page(page); put: put_page(page); out: return ret; } /* * Charge the memory controller for page usage. * Return * 0 if the charge was successful * < 0 if the cgroup is over its limit */ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, gfp_t gfp_mask, enum charge_type ctype) { struct mem_cgroup *memcg = NULL; unsigned int nr_pages = 1; struct page_cgroup *pc; bool oom = true; int ret; if (PageTransHuge(page)) { nr_pages <<= compound_order(page); VM_BUG_ON(!PageTransHuge(page)); /* * Never OOM-kill a process for a huge page. The * fault handler will fall back to regular pages. */ oom = false; } pc = lookup_page_cgroup(page); ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom); if (ret || !memcg) return ret; __mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype); return 0; } int mem_cgroup_newpage_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) { if (mem_cgroup_disabled()) return 0; VM_BUG_ON(page_mapped(page)); VM_BUG_ON(page->mapping && !PageAnon(page)); VM_BUG_ON(!mm); return mem_cgroup_charge_common(page, mm, gfp_mask, MEM_CGROUP_CHARGE_TYPE_MAPPED); } static void __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr, enum charge_type ctype); static void __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg, enum charge_type ctype) { struct page_cgroup *pc = lookup_page_cgroup(page); /* * In some case, SwapCache, FUSE(splice_buf->radixtree), the page * is already on LRU. It means the page may on some other page_cgroup's * LRU. Take care of it. */ mem_cgroup_lru_del_before_commit(page); __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype); mem_cgroup_lru_add_after_commit(page); return; } int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) { struct mem_cgroup *memcg = NULL; int ret; if (mem_cgroup_disabled()) return 0; if (PageCompound(page)) return 0; if (unlikely(!mm)) mm = &init_mm; if (page_is_file_cache(page)) { ret = __mem_cgroup_try_charge(mm, gfp_mask, 1, &memcg, true); if (ret || !memcg) return ret; /* * FUSE reuses pages without going through the final * put that would remove them from the LRU list, make * sure that they get relinked properly. */ __mem_cgroup_commit_charge_lrucare(page, memcg, MEM_CGROUP_CHARGE_TYPE_CACHE); return ret; } /* shmem */ if (PageSwapCache(page)) { ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &memcg); if (!ret) __mem_cgroup_commit_charge_swapin(page, memcg, MEM_CGROUP_CHARGE_TYPE_SHMEM); } else ret = mem_cgroup_charge_common(page, mm, gfp_mask, MEM_CGROUP_CHARGE_TYPE_SHMEM); return ret; } /* * While swap-in, try_charge -> commit or cancel, the page is locked. * And when try_charge() successfully returns, one refcnt to memcg without * struct page_cgroup is acquired. This refcnt will be consumed by * "commit()" or removed by "cancel()" */ int mem_cgroup_try_charge_swapin(struct mm_struct *mm, struct page *page, gfp_t mask, struct mem_cgroup **memcgp) { struct mem_cgroup *memcg; int ret; *memcgp = NULL; if (mem_cgroup_disabled()) return 0; if (!do_swap_account) goto charge_cur_mm; /* * A racing thread's fault, or swapoff, may have already updated * the pte, and even removed page from swap cache: in those cases * do_swap_page()'s pte_same() test will fail; but there's also a * KSM case which does need to charge the page. */ if (!PageSwapCache(page)) goto charge_cur_mm; memcg = try_get_mem_cgroup_from_page(page); if (!memcg) goto charge_cur_mm; *memcgp = memcg; ret = __mem_cgroup_try_charge(NULL, mask, 1, memcgp, true); css_put(&memcg->css); return ret; charge_cur_mm: if (unlikely(!mm)) mm = &init_mm; return __mem_cgroup_try_charge(mm, mask, 1, memcgp, true); } static void __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg, enum charge_type ctype) { if (mem_cgroup_disabled()) return; if (!memcg) return; cgroup_exclude_rmdir(&memcg->css); __mem_cgroup_commit_charge_lrucare(page, memcg, ctype); /* * Now swap is on-memory. This means this page may be * counted both as mem and swap....double count. * Fix it by uncharging from memsw. Basically, this SwapCache is stable * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page() * may call delete_from_swap_cache() before reach here. */ if (do_swap_account && PageSwapCache(page)) { swp_entry_t ent = {.val = page_private(page)}; struct mem_cgroup *swap_memcg; unsigned short id; id = swap_cgroup_record(ent, 0); rcu_read_lock(); swap_memcg = mem_cgroup_lookup(id); if (swap_memcg) { /* * This recorded memcg can be obsolete one. So, avoid * calling css_tryget */ if (!mem_cgroup_is_root(swap_memcg)) res_counter_uncharge(&swap_memcg->memsw, PAGE_SIZE); mem_cgroup_swap_statistics(swap_memcg, false); mem_cgroup_put(swap_memcg); } rcu_read_unlock(); } /* * At swapin, we may charge account against cgroup which has no tasks. * So, rmdir()->pre_destroy() can be called while we do this charge. * In that case, we need to call pre_destroy() again. check it here. */ cgroup_release_and_wakeup_rmdir(&memcg->css); } void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg) { __mem_cgroup_commit_charge_swapin(page, memcg, MEM_CGROUP_CHARGE_TYPE_MAPPED); } void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg) { if (mem_cgroup_disabled()) return; if (!memcg) return; __mem_cgroup_cancel_charge(memcg, 1); } static void mem_cgroup_do_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages, const enum charge_type ctype) { struct memcg_batch_info *batch = NULL; bool uncharge_memsw = true; /* If swapout, usage of swap doesn't decrease */ if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) uncharge_memsw = false; batch = &current->memcg_batch; /* * In usual, we do css_get() when we remember memcg pointer. * But in this case, we keep res->usage until end of a series of * uncharges. Then, it's ok to ignore memcg's refcnt. */ if (!batch->memcg) batch->memcg = memcg; /* * do_batch > 0 when unmapping pages or inode invalidate/truncate. * In those cases, all pages freed continuously can be expected to be in * the same cgroup and we have chance to coalesce uncharges. * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE) * because we want to do uncharge as soon as possible. */ if (!batch->do_batch || test_thread_flag(TIF_MEMDIE)) goto direct_uncharge; if (nr_pages > 1) goto direct_uncharge; /* * In typical case, batch->memcg == mem. This means we can * merge a series of uncharges to an uncharge of res_counter. * If not, we uncharge res_counter ony by one. */ if (batch->memcg != memcg) goto direct_uncharge; /* remember freed charge and uncharge it later */ batch->nr_pages++; if (uncharge_memsw) batch->memsw_nr_pages++; return; direct_uncharge: res_counter_uncharge(&memcg->res, nr_pages * PAGE_SIZE); if (uncharge_memsw) res_counter_uncharge(&memcg->memsw, nr_pages * PAGE_SIZE); if (unlikely(batch->memcg != memcg)) memcg_oom_recover(memcg); return; } /* * uncharge if !page_mapped(page) */ static struct mem_cgroup * __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) { struct mem_cgroup *memcg = NULL; unsigned int nr_pages = 1; struct page_cgroup *pc; if (mem_cgroup_disabled()) return NULL; if (PageSwapCache(page)) return NULL; if (PageTransHuge(page)) { nr_pages <<= compound_order(page); VM_BUG_ON(!PageTransHuge(page)); } /* * Check if our page_cgroup is valid */ pc = lookup_page_cgroup(page); if (unlikely(!PageCgroupUsed(pc))) return NULL; lock_page_cgroup(pc); memcg = pc->mem_cgroup; if (!PageCgroupUsed(pc)) goto unlock_out; switch (ctype) { case MEM_CGROUP_CHARGE_TYPE_MAPPED: case MEM_CGROUP_CHARGE_TYPE_DROP: /* See mem_cgroup_prepare_migration() */ if (page_mapped(page) || PageCgroupMigration(pc)) goto unlock_out; break; case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: if (!PageAnon(page)) { /* Shared memory */ if (page->mapping && !page_is_file_cache(page)) goto unlock_out; } else if (page_mapped(page)) /* Anon */ goto unlock_out; break; default: break; } mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), -nr_pages); ClearPageCgroupUsed(pc); /* * pc->mem_cgroup is not cleared here. It will be accessed when it's * freed from LRU. This is safe because uncharged page is expected not * to be reused (freed soon). Exception is SwapCache, it's handled by * special functions. */ unlock_page_cgroup(pc); /* * even after unlock, we have memcg->res.usage here and this memcg * will never be freed. */ memcg_check_events(memcg, page); if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) { mem_cgroup_swap_statistics(memcg, true); mem_cgroup_get(memcg); } if (!mem_cgroup_is_root(memcg)) mem_cgroup_do_uncharge(memcg, nr_pages, ctype); return memcg; unlock_out: unlock_page_cgroup(pc); return NULL; } void mem_cgroup_uncharge_page(struct page *page) { /* early check. */ if (page_mapped(page)) return; VM_BUG_ON(page->mapping && !PageAnon(page)); __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_MAPPED); } void mem_cgroup_uncharge_cache_page(struct page *page) { VM_BUG_ON(page_mapped(page)); VM_BUG_ON(page->mapping); __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); } /* * Batch_start/batch_end is called in unmap_page_range/invlidate/trucate. * In that cases, pages are freed continuously and we can expect pages * are in the same memcg. All these calls itself limits the number of * pages freed at once, then uncharge_start/end() is called properly. * This may be called prural(2) times in a context, */ void mem_cgroup_uncharge_start(void) { current->memcg_batch.do_batch++; /* We can do nest. */ if (current->memcg_batch.do_batch == 1) { current->memcg_batch.memcg = NULL; current->memcg_batch.nr_pages = 0; current->memcg_batch.memsw_nr_pages = 0; } } void mem_cgroup_uncharge_end(void) { struct memcg_batch_info *batch = &current->memcg_batch; if (!batch->do_batch) return; batch->do_batch--; if (batch->do_batch) /* If stacked, do nothing. */ return; if (!batch->memcg) return; /* * This "batch->memcg" is valid without any css_get/put etc... * bacause we hide charges behind us. */ if (batch->nr_pages) res_counter_uncharge(&batch->memcg->res, batch->nr_pages * PAGE_SIZE); if (batch->memsw_nr_pages) res_counter_uncharge(&batch->memcg->memsw, batch->memsw_nr_pages * PAGE_SIZE); memcg_oom_recover(batch->memcg); /* forget this pointer (for sanity check) */ batch->memcg = NULL; } #ifdef CONFIG_SWAP /* * called after __delete_from_swap_cache() and drop "page" account. * memcg information is recorded to swap_cgroup of "ent" */ void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout) { struct mem_cgroup *memcg; int ctype = MEM_CGROUP_CHARGE_TYPE_SWAPOUT; if (!swapout) /* this was a swap cache but the swap is unused ! */ ctype = MEM_CGROUP_CHARGE_TYPE_DROP; memcg = __mem_cgroup_uncharge_common(page, ctype); /* * record memcg information, if swapout && memcg != NULL, * mem_cgroup_get() was called in uncharge(). */ if (do_swap_account && swapout && memcg) swap_cgroup_record(ent, css_id(&memcg->css)); } #endif #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP /* * called from swap_entry_free(). remove record in swap_cgroup and * uncharge "memsw" account. */ void mem_cgroup_uncharge_swap(swp_entry_t ent) { struct mem_cgroup *memcg; unsigned short id; if (!do_swap_account) return; id = swap_cgroup_record(ent, 0); rcu_read_lock(); memcg = mem_cgroup_lookup(id); if (memcg) { /* * We uncharge this because swap is freed. * This memcg can be obsolete one. We avoid calling css_tryget */ if (!mem_cgroup_is_root(memcg)) res_counter_uncharge(&memcg->memsw, PAGE_SIZE); mem_cgroup_swap_statistics(memcg, false); mem_cgroup_put(memcg); } rcu_read_unlock(); } /** * mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record. * @entry: swap entry to be moved * @from: mem_cgroup which the entry is moved from * @to: mem_cgroup which the entry is moved to * @need_fixup: whether we should fixup res_counters and refcounts. * * It succeeds only when the swap_cgroup's record for this entry is the same * as the mem_cgroup's id of @from. * * Returns 0 on success, -EINVAL on failure. * * The caller must have charged to @to, IOW, called res_counter_charge() about * both res and memsw, and called css_get(). */ static int mem_cgroup_move_swap_account(swp_entry_t entry, struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) { unsigned short old_id, new_id; old_id = css_id(&from->css); new_id = css_id(&to->css); if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) { mem_cgroup_swap_statistics(from, false); mem_cgroup_swap_statistics(to, true); /* * This function is only called from task migration context now. * It postpones res_counter and refcount handling till the end * of task migration(mem_cgroup_clear_mc()) for performance * improvement. But we cannot postpone mem_cgroup_get(to) * because if the process that has been moved to @to does * swap-in, the refcount of @to might be decreased to 0. */ mem_cgroup_get(to); if (need_fixup) { if (!mem_cgroup_is_root(from)) res_counter_uncharge(&from->memsw, PAGE_SIZE); mem_cgroup_put(from); /* * we charged both to->res and to->memsw, so we should * uncharge to->res. */ if (!mem_cgroup_is_root(to)) res_counter_uncharge(&to->res, PAGE_SIZE); } return 0; } return -EINVAL; } #else static inline int mem_cgroup_move_swap_account(swp_entry_t entry, struct mem_cgroup *from, struct mem_cgroup *to, bool need_fixup) { return -EINVAL; } #endif /* * Before starting migration, account PAGE_SIZE to mem_cgroup that the old * page belongs to. */ int mem_cgroup_prepare_migration(struct page *page, struct page *newpage, struct mem_cgroup **memcgp, gfp_t gfp_mask) { struct mem_cgroup *memcg = NULL; struct page_cgroup *pc; enum charge_type ctype; int ret = 0; *memcgp = NULL; VM_BUG_ON(PageTransHuge(page)); if (mem_cgroup_disabled()) return 0; pc = lookup_page_cgroup(page); lock_page_cgroup(pc); if (PageCgroupUsed(pc)) { memcg = pc->mem_cgroup; css_get(&memcg->css); /* * At migrating an anonymous page, its mapcount goes down * to 0 and uncharge() will be called. But, even if it's fully * unmapped, migration may fail and this page has to be * charged again. We set MIGRATION flag here and delay uncharge * until end_migration() is called * * Corner Case Thinking * A) * When the old page was mapped as Anon and it's unmap-and-freed * while migration was ongoing. * If unmap finds the old page, uncharge() of it will be delayed * until end_migration(). If unmap finds a new page, it's * uncharged when it make mapcount to be 1->0. If unmap code * finds swap_migration_entry, the new page will not be mapped * and end_migration() will find it(mapcount==0). * * B) * When the old page was mapped but migraion fails, the kernel * remaps it. A charge for it is kept by MIGRATION flag even * if mapcount goes down to 0. We can do remap successfully * without charging it again. * * C) * The "old" page is under lock_page() until the end of * migration, so, the old page itself will not be swapped-out. * If the new page is swapped out before end_migraton, our * hook to usual swap-out path will catch the event. */ if (PageAnon(page)) SetPageCgroupMigration(pc); } unlock_page_cgroup(pc); /* * If the page is not charged at this point, * we return here. */ if (!memcg) return 0; *memcgp = memcg; ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, memcgp, false); css_put(&memcg->css);/* drop extra refcnt */ if (ret || *memcgp == NULL) { if (PageAnon(page)) { lock_page_cgroup(pc); ClearPageCgroupMigration(pc); unlock_page_cgroup(pc); /* * The old page may be fully unmapped while we kept it. */ mem_cgroup_uncharge_page(page); } return -ENOMEM; } /* * We charge new page before it's used/mapped. So, even if unlock_page() * is called before end_migration, we can catch all events on this new * page. In the case new page is migrated but not remapped, new page's * mapcount will be finally 0 and we call uncharge in end_migration(). */ pc = lookup_page_cgroup(newpage); if (PageAnon(page)) ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; else if (page_is_file_cache(page)) ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; else ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype); return ret; } /* remove redundant charge if migration failed*/ void mem_cgroup_end_migration(struct mem_cgroup *memcg, struct page *oldpage, struct page *newpage, bool migration_ok) { struct page *used, *unused; struct page_cgroup *pc; if (!memcg) return; /* blocks rmdir() */ cgroup_exclude_rmdir(&memcg->css); if (!migration_ok) { used = oldpage; unused = newpage; } else { used = newpage; unused = oldpage; } /* * We disallowed uncharge of pages under migration because mapcount * of the page goes down to zero, temporarly. * Clear the flag and check the page should be charged. */ pc = lookup_page_cgroup(oldpage); lock_page_cgroup(pc); ClearPageCgroupMigration(pc); unlock_page_cgroup(pc); __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE); /* * If a page is a file cache, radix-tree replacement is very atomic * and we can skip this check. When it was an Anon page, its mapcount * goes down to 0. But because we added MIGRATION flage, it's not * uncharged yet. There are several case but page->mapcount check * and USED bit check in mem_cgroup_uncharge_page() will do enough * check. (see prepare_charge() also) */ if (PageAnon(used)) mem_cgroup_uncharge_page(used); /* * At migration, we may charge account against cgroup which has no * tasks. * So, rmdir()->pre_destroy() can be called while we do this charge. * In that case, we need to call pre_destroy() again. check it here. */ cgroup_release_and_wakeup_rmdir(&memcg->css); } /* * At replace page cache, newpage is not under any memcg but it's on * LRU. So, this function doesn't touch res_counter but handles LRU * in correct way. Both pages are locked so we cannot race with uncharge. */ void mem_cgroup_replace_page_cache(struct page *oldpage, struct page *newpage) { struct mem_cgroup *memcg; struct page_cgroup *pc; struct zone *zone; enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE; unsigned long flags; if (mem_cgroup_disabled()) return; pc = lookup_page_cgroup(oldpage); /* fix accounting on old pages */ lock_page_cgroup(pc); memcg = pc->mem_cgroup; mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), -1); ClearPageCgroupUsed(pc); unlock_page_cgroup(pc); if (PageSwapBacked(oldpage)) type = MEM_CGROUP_CHARGE_TYPE_SHMEM; zone = page_zone(newpage); pc = lookup_page_cgroup(newpage); /* * Even if newpage->mapping was NULL before starting replacement, * the newpage may be on LRU(or pagevec for LRU) already. We lock * LRU while we overwrite pc->mem_cgroup. */ spin_lock_irqsave(&zone->lru_lock, flags); if (PageLRU(newpage)) del_page_from_lru_list(zone, newpage, page_lru(newpage)); __mem_cgroup_commit_charge(memcg, newpage, 1, pc, type); if (PageLRU(newpage)) add_page_to_lru_list(zone, newpage, page_lru(newpage)); spin_unlock_irqrestore(&zone->lru_lock, flags); } #ifdef CONFIG_DEBUG_VM static struct page_cgroup *lookup_page_cgroup_used(struct page *page) { struct page_cgroup *pc; pc = lookup_page_cgroup(page); /* * Can be NULL while feeding pages into the page allocator for * the first time, i.e. during boot or memory hotplug; * or when mem_cgroup_disabled(). */ if (likely(pc) && PageCgroupUsed(pc)) return pc; return NULL; } bool mem_cgroup_bad_page_check(struct page *page) { if (mem_cgroup_disabled()) return false; return lookup_page_cgroup_used(page) != NULL; } void mem_cgroup_print_bad_page(struct page *page) { struct page_cgroup *pc; pc = lookup_page_cgroup_used(page); if (pc) { int ret = -1; char *path; printk(KERN_ALERT "pc:%p pc->flags:%lx pc->mem_cgroup:%p", pc, pc->flags, pc->mem_cgroup); path = kmalloc(PATH_MAX, GFP_KERNEL); if (path) { rcu_read_lock(); ret = cgroup_path(pc->mem_cgroup->css.cgroup, path, PATH_MAX); rcu_read_unlock(); } printk(KERN_CONT "(%s)\n", (ret < 0) ? "cannot get the path" : path); kfree(path); } } #endif static DEFINE_MUTEX(set_limit_mutex); static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, unsigned long long val) { int retry_count; u64 memswlimit, memlimit; int ret = 0; int children = mem_cgroup_count_children(memcg); u64 curusage, oldusage; int enlarge; /* * For keeping hierarchical_reclaim simple, how long we should retry * is depends on callers. We set our retry-count to be function * of # of children which we should visit in this loop. */ retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); enlarge = 0; while (retry_count) { if (signal_pending(current)) { ret = -EINTR; break; } /* * Rather than hide all in some function, I do this in * open coded manner. You see what this really does. * We have to guarantee memcg->res.limit < memcg->memsw.limit. */ mutex_lock(&set_limit_mutex); memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); if (memswlimit < val) { ret = -EINVAL; mutex_unlock(&set_limit_mutex); break; } memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); if (memlimit < val) enlarge = 1; ret = res_counter_set_limit(&memcg->res, val); if (!ret) { if (memswlimit == val) memcg->memsw_is_minimum = true; else memcg->memsw_is_minimum = false; } mutex_unlock(&set_limit_mutex); if (!ret) break; mem_cgroup_reclaim(memcg, GFP_KERNEL, MEM_CGROUP_RECLAIM_SHRINK); curusage = res_counter_read_u64(&memcg->res, RES_USAGE); /* Usage is reduced ? */ if (curusage >= oldusage) retry_count--; else oldusage = curusage; } if (!ret && enlarge) memcg_oom_recover(memcg); return ret; } static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, unsigned long long val) { int retry_count; u64 memlimit, memswlimit, oldusage, curusage; int children = mem_cgroup_count_children(memcg); int ret = -EBUSY; int enlarge = 0; /* see mem_cgroup_resize_res_limit */ retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); while (retry_count) { if (signal_pending(current)) { ret = -EINTR; break; } /* * Rather than hide all in some function, I do this in * open coded manner. You see what this really does. * We have to guarantee memcg->res.limit < memcg->memsw.limit. */ mutex_lock(&set_limit_mutex); memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT); if (memlimit > val) { ret = -EINVAL; mutex_unlock(&set_limit_mutex); break; } memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); if (memswlimit < val) enlarge = 1; ret = res_counter_set_limit(&memcg->memsw, val); if (!ret) { if (memlimit == val) memcg->memsw_is_minimum = true; else memcg->memsw_is_minimum = false; } mutex_unlock(&set_limit_mutex); if (!ret) break; mem_cgroup_reclaim(memcg, GFP_KERNEL, MEM_CGROUP_RECLAIM_NOSWAP | MEM_CGROUP_RECLAIM_SHRINK); curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); /* Usage is reduced ? */ if (curusage >= oldusage) retry_count--; else oldusage = curusage; } if (!ret && enlarge) memcg_oom_recover(memcg); return ret; } unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, gfp_t gfp_mask, unsigned long *total_scanned) { unsigned long nr_reclaimed = 0; struct mem_cgroup_per_zone *mz, *next_mz = NULL; unsigned long reclaimed; int loop = 0; struct mem_cgroup_tree_per_zone *mctz; unsigned long long excess; unsigned long nr_scanned; if (order > 0) return 0; mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone)); /* * This loop can run a while, specially if mem_cgroup's continuously * keep exceeding their soft limit and putting the system under * pressure */ do { if (next_mz) mz = next_mz; else mz = mem_cgroup_largest_soft_limit_node(mctz); if (!mz) break; nr_scanned = 0; reclaimed = mem_cgroup_soft_reclaim(mz->mem, zone, gfp_mask, &nr_scanned); nr_reclaimed += reclaimed; *total_scanned += nr_scanned; spin_lock(&mctz->lock); /* * If we failed to reclaim anything from this memory cgroup * it is time to move on to the next cgroup */ next_mz = NULL; if (!reclaimed) { do { /* * Loop until we find yet another one. * * By the time we get the soft_limit lock * again, someone might have aded the * group back on the RB tree. Iterate to * make sure we get a different mem. * mem_cgroup_largest_soft_limit_node returns * NULL if no other cgroup is present on * the tree */ next_mz = __mem_cgroup_largest_soft_limit_node(mctz); if (next_mz == mz) css_put(&next_mz->mem->css); else /* next_mz == NULL or other memcg */ break; } while (1); } __mem_cgroup_remove_exceeded(mz->mem, mz, mctz); excess = res_counter_soft_limit_excess(&mz->mem->res); /* * One school of thought says that we should not add * back the node to the tree if reclaim returns 0. * But our reclaim could return 0, simply because due * to priority we are exposing a smaller subset of * memory to reclaim from. Consider this as a longer * term TODO. */ /* If excess == 0, no tree ops */ __mem_cgroup_insert_exceeded(mz->mem, mz, mctz, excess); spin_unlock(&mctz->lock); css_put(&mz->mem->css); loop++; /* * Could not reclaim anything and there are no more * mem cgroups to try or we seem to be looping without * reclaiming anything. */ if (!nr_reclaimed && (next_mz == NULL || loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) break; } while (!nr_reclaimed); if (next_mz) css_put(&next_mz->mem->css); return nr_reclaimed; } /* * This routine traverse page_cgroup in given list and drop them all. * *And* this routine doesn't reclaim page itself, just removes page_cgroup. */ static int mem_cgroup_force_empty_list(struct mem_cgroup *memcg, int node, int zid, enum lru_list lru) { struct mem_cgroup_per_zone *mz; unsigned long flags, loop; struct list_head *list; struct page *busy; struct zone *zone; int ret = 0; zone = &NODE_DATA(node)->node_zones[zid]; mz = mem_cgroup_zoneinfo(memcg, node, zid); list = &mz->lruvec.lists[lru]; loop = MEM_CGROUP_ZSTAT(mz, lru); /* give some margin against EBUSY etc...*/ loop += 256; busy = NULL; while (loop--) { struct page_cgroup *pc; struct page *page; ret = 0; spin_lock_irqsave(&zone->lru_lock, flags); if (list_empty(list)) { spin_unlock_irqrestore(&zone->lru_lock, flags); break; } page = list_entry(list->prev, struct page, lru); if (busy == page) { list_move(&page->lru, list); busy = NULL; spin_unlock_irqrestore(&zone->lru_lock, flags); continue; } spin_unlock_irqrestore(&zone->lru_lock, flags); pc = lookup_page_cgroup(page); ret = mem_cgroup_move_parent(page, pc, memcg, GFP_KERNEL); if (ret == -ENOMEM) break; if (ret == -EBUSY || ret == -EINVAL) { /* found lock contention or "pc" is obsolete. */ busy = page; cond_resched(); } else busy = NULL; } if (!ret && !list_empty(list)) return -EBUSY; return ret; } /* * make mem_cgroup's charge to be 0 if there is no task. * This enables deleting this mem_cgroup. */ static int mem_cgroup_force_empty(struct mem_cgroup *memcg, bool free_all) { int ret; int node, zid, shrink; int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; struct cgroup *cgrp = memcg->css.cgroup; css_get(&memcg->css); shrink = 0; /* should free all ? */ if (free_all) goto try_to_free; move_account: do { ret = -EBUSY; if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children)) goto out; ret = -EINTR; if (signal_pending(current)) goto out; /* This is for making all *used* pages to be on LRU. */ lru_add_drain_all(); drain_all_stock_sync(memcg); ret = 0; mem_cgroup_start_move(memcg); for_each_node_state(node, N_HIGH_MEMORY) { for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { enum lru_list l; for_each_lru(l) { ret = mem_cgroup_force_empty_list(memcg, node, zid, l); if (ret) break; } } if (ret) break; } mem_cgroup_end_move(memcg); memcg_oom_recover(memcg); /* it seems parent cgroup doesn't have enough mem */ if (ret == -ENOMEM) goto try_to_free; cond_resched(); /* "ret" should also be checked to ensure all lists are empty. */ } while (memcg->res.usage > 0 || ret); out: css_put(&memcg->css); return ret; try_to_free: /* returns EBUSY if there is a task or if we come here twice. */ if (cgroup_task_count(cgrp) || !list_empty(&cgrp->children) || shrink) { ret = -EBUSY; goto out; } /* we call try-to-free pages for make this cgroup empty */ lru_add_drain_all(); /* try to free all pages in this cgroup */ shrink = 1; while (nr_retries && memcg->res.usage > 0) { int progress; if (signal_pending(current)) { ret = -EINTR; goto out; } progress = try_to_free_mem_cgroup_pages(memcg, GFP_KERNEL, false); if (!progress) { nr_retries--; /* maybe some writeback is necessary */ congestion_wait(BLK_RW_ASYNC, HZ/10); } } lru_add_drain(); /* try move_account...there may be some *locked* pages. */ goto move_account; } int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event) { return mem_cgroup_force_empty(mem_cgroup_from_cont(cont), true); } static u64 mem_cgroup_hierarchy_read(struct cgroup *cont, struct cftype *cft) { return mem_cgroup_from_cont(cont)->use_hierarchy; } static int mem_cgroup_hierarchy_write(struct cgroup *cont, struct cftype *cft, u64 val) { int retval = 0; struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); struct cgroup *parent = cont->parent; struct mem_cgroup *parent_memcg = NULL; if (parent) parent_memcg = mem_cgroup_from_cont(parent); cgroup_lock(); /* * If parent's use_hierarchy is set, we can't make any modifications * in the child subtrees. If it is unset, then the change can * occur, provided the current cgroup has no children. * * For the root cgroup, parent_mem is NULL, we allow value to be * set if there are no children. */ if ((!parent_memcg || !parent_memcg->use_hierarchy) && (val == 1 || val == 0)) { if (list_empty(&cont->children)) memcg->use_hierarchy = val; else retval = -EBUSY; } else retval = -EINVAL; cgroup_unlock(); return retval; } static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *memcg, enum mem_cgroup_stat_index idx) { struct mem_cgroup *iter; long val = 0; /* Per-cpu values can be negative, use a signed accumulator */ for_each_mem_cgroup_tree(iter, memcg) val += mem_cgroup_read_stat(iter, idx); if (val < 0) /* race ? */ val = 0; return val; } static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) { u64 val; if (!mem_cgroup_is_root(memcg)) { if (!swap) return res_counter_read_u64(&memcg->res, RES_USAGE); else return res_counter_read_u64(&memcg->memsw, RES_USAGE); } val = mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_CACHE); val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_RSS); if (swap) val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_SWAPOUT); return val << PAGE_SHIFT; } static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); u64 val; int type, name; type = MEMFILE_TYPE(cft->private); name = MEMFILE_ATTR(cft->private); switch (type) { case _MEM: if (name == RES_USAGE) val = mem_cgroup_usage(memcg, false); else val = res_counter_read_u64(&memcg->res, name); break; case _MEMSWAP: if (name == RES_USAGE) val = mem_cgroup_usage(memcg, true); else val = res_counter_read_u64(&memcg->memsw, name); break; default: BUG(); break; } return val; } /* * The user of this function is... * RES_LIMIT. */ static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, const char *buffer) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); int type, name; unsigned long long val; int ret; type = MEMFILE_TYPE(cft->private); name = MEMFILE_ATTR(cft->private); switch (name) { case RES_LIMIT: if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ ret = -EINVAL; break; } /* This function does all necessary parse...reuse it */ ret = res_counter_memparse_write_strategy(buffer, &val); if (ret) break; if (type == _MEM) ret = mem_cgroup_resize_limit(memcg, val); else ret = mem_cgroup_resize_memsw_limit(memcg, val); break; case RES_SOFT_LIMIT: ret = res_counter_memparse_write_strategy(buffer, &val); if (ret) break; /* * For memsw, soft limits are hard to implement in terms * of semantics, for now, we support soft limits for * control without swap */ if (type == _MEM) ret = res_counter_set_soft_limit(&memcg->res, val); else ret = -EINVAL; break; default: ret = -EINVAL; /* should be BUG() ? */ break; } return ret; } static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, unsigned long long *mem_limit, unsigned long long *memsw_limit) { struct cgroup *cgroup; unsigned long long min_limit, min_memsw_limit, tmp; min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); cgroup = memcg->css.cgroup; if (!memcg->use_hierarchy) goto out; while (cgroup->parent) { cgroup = cgroup->parent; memcg = mem_cgroup_from_cont(cgroup); if (!memcg->use_hierarchy) break; tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); min_limit = min(min_limit, tmp); tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); min_memsw_limit = min(min_memsw_limit, tmp); } out: *mem_limit = min_limit; *memsw_limit = min_memsw_limit; return; } static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) { struct mem_cgroup *memcg; int type, name; memcg = mem_cgroup_from_cont(cont); type = MEMFILE_TYPE(event); name = MEMFILE_ATTR(event); switch (name) { case RES_MAX_USAGE: if (type == _MEM) res_counter_reset_max(&memcg->res); else res_counter_reset_max(&memcg->memsw); break; case RES_FAILCNT: if (type == _MEM) res_counter_reset_failcnt(&memcg->res); else res_counter_reset_failcnt(&memcg->memsw); break; } return 0; } static u64 mem_cgroup_move_charge_read(struct cgroup *cgrp, struct cftype *cft) { return mem_cgroup_from_cont(cgrp)->move_charge_at_immigrate; } #ifdef CONFIG_MMU static int mem_cgroup_move_charge_write(struct cgroup *cgrp, struct cftype *cft, u64 val) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); if (val >= (1 << NR_MOVE_TYPE)) return -EINVAL; /* * We check this value several times in both in can_attach() and * attach(), so we need cgroup lock to prevent this value from being * inconsistent. */ cgroup_lock(); memcg->move_charge_at_immigrate = val; cgroup_unlock(); return 0; } #else static int mem_cgroup_move_charge_write(struct cgroup *cgrp, struct cftype *cft, u64 val) { return -ENOSYS; } #endif /* For read statistics */ enum { MCS_CACHE, MCS_RSS, MCS_FILE_MAPPED, MCS_PGPGIN, MCS_PGPGOUT, MCS_SWAP, MCS_PGFAULT, MCS_PGMAJFAULT, MCS_INACTIVE_ANON, MCS_ACTIVE_ANON, MCS_INACTIVE_FILE, MCS_ACTIVE_FILE, MCS_UNEVICTABLE, NR_MCS_STAT, }; struct mcs_total_stat { s64 stat[NR_MCS_STAT]; }; struct { char *local_name; char *total_name; } memcg_stat_strings[NR_MCS_STAT] = { {"cache", "total_cache"}, {"rss", "total_rss"}, {"mapped_file", "total_mapped_file"}, {"pgpgin", "total_pgpgin"}, {"pgpgout", "total_pgpgout"}, {"swap", "total_swap"}, {"pgfault", "total_pgfault"}, {"pgmajfault", "total_pgmajfault"}, {"inactive_anon", "total_inactive_anon"}, {"active_anon", "total_active_anon"}, {"inactive_file", "total_inactive_file"}, {"active_file", "total_active_file"}, {"unevictable", "total_unevictable"} }; static void mem_cgroup_get_local_stat(struct mem_cgroup *memcg, struct mcs_total_stat *s) { s64 val; /* per cpu stat */ val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_CACHE); s->stat[MCS_CACHE] += val * PAGE_SIZE; val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_RSS); s->stat[MCS_RSS] += val * PAGE_SIZE; val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED); s->stat[MCS_FILE_MAPPED] += val * PAGE_SIZE; val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGPGIN); s->stat[MCS_PGPGIN] += val; val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGPGOUT); s->stat[MCS_PGPGOUT] += val; if (do_swap_account) { val = mem_cgroup_read_stat(memcg, MEM_CGROUP_STAT_SWAPOUT); s->stat[MCS_SWAP] += val * PAGE_SIZE; } val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGFAULT); s->stat[MCS_PGFAULT] += val; val = mem_cgroup_read_events(memcg, MEM_CGROUP_EVENTS_PGMAJFAULT); s->stat[MCS_PGMAJFAULT] += val; /* per zone stat */ val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_ANON)); s->stat[MCS_INACTIVE_ANON] += val * PAGE_SIZE; val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_ANON)); s->stat[MCS_ACTIVE_ANON] += val * PAGE_SIZE; val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_INACTIVE_FILE)); s->stat[MCS_INACTIVE_FILE] += val * PAGE_SIZE; val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_ACTIVE_FILE)); s->stat[MCS_ACTIVE_FILE] += val * PAGE_SIZE; val = mem_cgroup_nr_lru_pages(memcg, BIT(LRU_UNEVICTABLE)); s->stat[MCS_UNEVICTABLE] += val * PAGE_SIZE; } static void mem_cgroup_get_total_stat(struct mem_cgroup *memcg, struct mcs_total_stat *s) { struct mem_cgroup *iter; for_each_mem_cgroup_tree(iter, memcg) mem_cgroup_get_local_stat(iter, s); } #ifdef CONFIG_NUMA static int mem_control_numa_stat_show(struct seq_file *m, void *arg) { int nid; unsigned long total_nr, file_nr, anon_nr, unevictable_nr; unsigned long node_nr; struct cgroup *cont = m->private; struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); total_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL); seq_printf(m, "total=%lu", total_nr); for_each_node_state(nid, N_HIGH_MEMORY) { node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, LRU_ALL); seq_printf(m, " N%d=%lu", nid, node_nr); } seq_putc(m, '\n'); file_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_FILE); seq_printf(m, "file=%lu", file_nr); for_each_node_state(nid, N_HIGH_MEMORY) { node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, LRU_ALL_FILE); seq_printf(m, " N%d=%lu", nid, node_nr); } seq_putc(m, '\n'); anon_nr = mem_cgroup_nr_lru_pages(mem_cont, LRU_ALL_ANON); seq_printf(m, "anon=%lu", anon_nr); for_each_node_state(nid, N_HIGH_MEMORY) { node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, LRU_ALL_ANON); seq_printf(m, " N%d=%lu", nid, node_nr); } seq_putc(m, '\n'); unevictable_nr = mem_cgroup_nr_lru_pages(mem_cont, BIT(LRU_UNEVICTABLE)); seq_printf(m, "unevictable=%lu", unevictable_nr); for_each_node_state(nid, N_HIGH_MEMORY) { node_nr = mem_cgroup_node_nr_lru_pages(mem_cont, nid, BIT(LRU_UNEVICTABLE)); seq_printf(m, " N%d=%lu", nid, node_nr); } seq_putc(m, '\n'); return 0; } #endif /* CONFIG_NUMA */ static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, struct cgroup_map_cb *cb) { struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont); struct mcs_total_stat mystat; int i; memset(&mystat, 0, sizeof(mystat)); mem_cgroup_get_local_stat(mem_cont, &mystat); for (i = 0; i < NR_MCS_STAT; i++) { if (i == MCS_SWAP && !do_swap_account) continue; cb->fill(cb, memcg_stat_strings[i].local_name, mystat.stat[i]); } /* Hierarchical information */ { unsigned long long limit, memsw_limit; memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit); cb->fill(cb, "hierarchical_memory_limit", limit); if (do_swap_account) cb->fill(cb, "hierarchical_memsw_limit", memsw_limit); } memset(&mystat, 0, sizeof(mystat)); mem_cgroup_get_total_stat(mem_cont, &mystat); for (i = 0; i < NR_MCS_STAT; i++) { if (i == MCS_SWAP && !do_swap_account) continue; cb->fill(cb, memcg_stat_strings[i].total_name, mystat.stat[i]); } #ifdef CONFIG_DEBUG_VM { int nid, zid; struct mem_cgroup_per_zone *mz; unsigned long recent_rotated[2] = {0, 0}; unsigned long recent_scanned[2] = {0, 0}; for_each_online_node(nid) for (zid = 0; zid < MAX_NR_ZONES; zid++) { mz = mem_cgroup_zoneinfo(mem_cont, nid, zid); recent_rotated[0] += mz->reclaim_stat.recent_rotated[0]; recent_rotated[1] += mz->reclaim_stat.recent_rotated[1]; recent_scanned[0] += mz->reclaim_stat.recent_scanned[0]; recent_scanned[1] += mz->reclaim_stat.recent_scanned[1]; } cb->fill(cb, "recent_rotated_anon", recent_rotated[0]); cb->fill(cb, "recent_rotated_file", recent_rotated[1]); cb->fill(cb, "recent_scanned_anon", recent_scanned[0]); cb->fill(cb, "recent_scanned_file", recent_scanned[1]); } #endif return 0; } static u64 mem_cgroup_swappiness_read(struct cgroup *cgrp, struct cftype *cft) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); return mem_cgroup_swappiness(memcg); } static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, u64 val) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); struct mem_cgroup *parent; if (val > 100) return -EINVAL; if (cgrp->parent == NULL) return -EINVAL; parent = mem_cgroup_from_cont(cgrp->parent); cgroup_lock(); /* If under hierarchy, only empty-root can set this value */ if ((parent->use_hierarchy) || (memcg->use_hierarchy && !list_empty(&cgrp->children))) { cgroup_unlock(); return -EINVAL; } memcg->swappiness = val; cgroup_unlock(); return 0; } static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) { struct mem_cgroup_threshold_ary *t; u64 usage; int i; rcu_read_lock(); if (!swap) t = rcu_dereference(memcg->thresholds.primary); else t = rcu_dereference(memcg->memsw_thresholds.primary); if (!t) goto unlock; usage = mem_cgroup_usage(memcg, swap); /* * current_threshold points to threshold just below usage. * If it's not true, a threshold was crossed after last * call of __mem_cgroup_threshold(). */ i = t->current_threshold; /* * Iterate backward over array of thresholds starting from * current_threshold and check if a threshold is crossed. * If none of thresholds below usage is crossed, we read * only one element of the array here. */ for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--) eventfd_signal(t->entries[i].eventfd, 1); /* i = current_threshold + 1 */ i++; /* * Iterate forward over array of thresholds starting from * current_threshold+1 and check if a threshold is crossed. * If none of thresholds above usage is crossed, we read * only one element of the array here. */ for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++) eventfd_signal(t->entries[i].eventfd, 1); /* Update current_threshold */ t->current_threshold = i - 1; unlock: rcu_read_unlock(); } static void mem_cgroup_threshold(struct mem_cgroup *memcg) { while (memcg) { __mem_cgroup_threshold(memcg, false); if (do_swap_account) __mem_cgroup_threshold(memcg, true); memcg = parent_mem_cgroup(memcg); } } static int compare_thresholds(const void *a, const void *b) { const struct mem_cgroup_threshold *_a = a; const struct mem_cgroup_threshold *_b = b; return _a->threshold - _b->threshold; } static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg) { struct mem_cgroup_eventfd_list *ev; list_for_each_entry(ev, &memcg->oom_notify, list) eventfd_signal(ev->eventfd, 1); return 0; } static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) { struct mem_cgroup *iter; for_each_mem_cgroup_tree(iter, memcg) mem_cgroup_oom_notify_cb(iter); } static int mem_cgroup_usage_register_event(struct cgroup *cgrp, struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; int type = MEMFILE_TYPE(cft->private); u64 threshold, usage; int i, size, ret; ret = res_counter_memparse_write_strategy(args, &threshold); if (ret) return ret; mutex_lock(&memcg->thresholds_lock); if (type == _MEM) thresholds = &memcg->thresholds; else if (type == _MEMSWAP) thresholds = &memcg->memsw_thresholds; else BUG(); usage = mem_cgroup_usage(memcg, type == _MEMSWAP); /* Check if a threshold crossed before adding a new one */ if (thresholds->primary) __mem_cgroup_threshold(memcg, type == _MEMSWAP); size = thresholds->primary ? thresholds->primary->size + 1 : 1; /* Allocate memory for new array of thresholds */ new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold), GFP_KERNEL); if (!new) { ret = -ENOMEM; goto unlock; } new->size = size; /* Copy thresholds (if any) to new array */ if (thresholds->primary) { memcpy(new->entries, thresholds->primary->entries, (size - 1) * sizeof(struct mem_cgroup_threshold)); } /* Add new threshold */ new->entries[size - 1].eventfd = eventfd; new->entries[size - 1].threshold = threshold; /* Sort thresholds. Registering of new threshold isn't time-critical */ sort(new->entries, size, sizeof(struct mem_cgroup_threshold), compare_thresholds, NULL); /* Find current threshold */ new->current_threshold = -1; for (i = 0; i < size; i++) { if (new->entries[i].threshold < usage) { /* * new->current_threshold will not be used until * rcu_assign_pointer(), so it's safe to increment * it here. */ ++new->current_threshold; } } /* Free old spare buffer and save old primary buffer as spare */ kfree(thresholds->spare); thresholds->spare = thresholds->primary; rcu_assign_pointer(thresholds->primary, new); /* To be sure that nobody uses thresholds */ synchronize_rcu(); unlock: mutex_unlock(&memcg->thresholds_lock); return ret; } static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp, struct cftype *cft, struct eventfd_ctx *eventfd) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; int type = MEMFILE_TYPE(cft->private); u64 usage; int i, j, size; mutex_lock(&memcg->thresholds_lock); if (type == _MEM) thresholds = &memcg->thresholds; else if (type == _MEMSWAP) thresholds = &memcg->memsw_thresholds; else BUG(); /* * Something went wrong if we trying to unregister a threshold * if we don't have thresholds */ BUG_ON(!thresholds); usage = mem_cgroup_usage(memcg, type == _MEMSWAP); /* Check if a threshold crossed before removing */ __mem_cgroup_threshold(memcg, type == _MEMSWAP); /* Calculate new number of threshold */ size = 0; for (i = 0; i < thresholds->primary->size; i++) { if (thresholds->primary->entries[i].eventfd != eventfd) size++; } new = thresholds->spare; /* Set thresholds array to NULL if we don't have thresholds */ if (!size) { kfree(new); new = NULL; goto swap_buffers; } new->size = size; /* Copy thresholds and find current threshold */ new->current_threshold = -1; for (i = 0, j = 0; i < thresholds->primary->size; i++) { if (thresholds->primary->entries[i].eventfd == eventfd) continue; new->entries[j] = thresholds->primary->entries[i]; if (new->entries[j].threshold < usage) { /* * new->current_threshold will not be used * until rcu_assign_pointer(), so it's safe to increment * it here. */ ++new->current_threshold; } j++; } swap_buffers: /* Swap primary and spare array */ thresholds->spare = thresholds->primary; rcu_assign_pointer(thresholds->primary, new); /* To be sure that nobody uses thresholds */ synchronize_rcu(); mutex_unlock(&memcg->thresholds_lock); } static int mem_cgroup_oom_register_event(struct cgroup *cgrp, struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); struct mem_cgroup_eventfd_list *event; int type = MEMFILE_TYPE(cft->private); BUG_ON(type != _OOM_TYPE); event = kmalloc(sizeof(*event), GFP_KERNEL); if (!event) return -ENOMEM; spin_lock(&memcg_oom_lock); event->eventfd = eventfd; list_add(&event->list, &memcg->oom_notify); /* already in OOM ? */ if (atomic_read(&memcg->under_oom)) eventfd_signal(eventfd, 1); spin_unlock(&memcg_oom_lock); return 0; } static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, struct cftype *cft, struct eventfd_ctx *eventfd) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); struct mem_cgroup_eventfd_list *ev, *tmp; int type = MEMFILE_TYPE(cft->private); BUG_ON(type != _OOM_TYPE); spin_lock(&memcg_oom_lock); list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) { if (ev->eventfd == eventfd) { list_del(&ev->list); kfree(ev); } } spin_unlock(&memcg_oom_lock); } static int mem_cgroup_oom_control_read(struct cgroup *cgrp, struct cftype *cft, struct cgroup_map_cb *cb) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); cb->fill(cb, "oom_kill_disable", memcg->oom_kill_disable); if (atomic_read(&memcg->under_oom)) cb->fill(cb, "under_oom", 1); else cb->fill(cb, "under_oom", 0); return 0; } static int mem_cgroup_oom_control_write(struct cgroup *cgrp, struct cftype *cft, u64 val) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); struct mem_cgroup *parent; /* cannot set to root cgroup and only 0 and 1 are allowed */ if (!cgrp->parent || !((val == 0) || (val == 1))) return -EINVAL; parent = mem_cgroup_from_cont(cgrp->parent); cgroup_lock(); /* oom-kill-disable is a flag for subhierarchy. */ if ((parent->use_hierarchy) || (memcg->use_hierarchy && !list_empty(&cgrp->children))) { cgroup_unlock(); return -EINVAL; } memcg->oom_kill_disable = val; if (!val) memcg_oom_recover(memcg); cgroup_unlock(); return 0; } #ifdef CONFIG_NUMA static const struct file_operations mem_control_numa_stat_file_operations = { .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static int mem_control_numa_stat_open(struct inode *unused, struct file *file) { struct cgroup *cont = file->f_dentry->d_parent->d_fsdata; file->f_op = &mem_control_numa_stat_file_operations; return single_open(file, mem_control_numa_stat_show, cont); } #endif /* CONFIG_NUMA */ #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss) { /* * Part of this would be better living in a separate allocation * function, leaving us with just the cgroup tree population work. * We, however, depend on state such as network's proto_list that * is only initialized after cgroup creation. I found the less * cumbersome way to deal with it to defer it all to populate time */ return mem_cgroup_sockets_init(cont, ss); }; static void kmem_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cont) { mem_cgroup_sockets_destroy(cont, ss); } #else static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss) { return 0; } static void kmem_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cont) { } #endif static struct cftype mem_cgroup_files[] = { { .name = "usage_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), .read_u64 = mem_cgroup_read, .register_event = mem_cgroup_usage_register_event, .unregister_event = mem_cgroup_usage_unregister_event, }, { .name = "max_usage_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), .trigger = mem_cgroup_reset, .read_u64 = mem_cgroup_read, }, { .name = "limit_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), .write_string = mem_cgroup_write, .read_u64 = mem_cgroup_read, }, { .name = "soft_limit_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), .write_string = mem_cgroup_write, .read_u64 = mem_cgroup_read, }, { .name = "failcnt", .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), .trigger = mem_cgroup_reset, .read_u64 = mem_cgroup_read, }, { .name = "stat", .read_map = mem_control_stat_show, }, { .name = "force_empty", .trigger = mem_cgroup_force_empty_write, }, { .name = "use_hierarchy", .write_u64 = mem_cgroup_hierarchy_write, .read_u64 = mem_cgroup_hierarchy_read, }, { .name = "swappiness", .read_u64 = mem_cgroup_swappiness_read, .write_u64 = mem_cgroup_swappiness_write, }, { .name = "move_charge_at_immigrate", .read_u64 = mem_cgroup_move_charge_read, .write_u64 = mem_cgroup_move_charge_write, }, { .name = "oom_control", .read_map = mem_cgroup_oom_control_read, .write_u64 = mem_cgroup_oom_control_write, .register_event = mem_cgroup_oom_register_event, .unregister_event = mem_cgroup_oom_unregister_event, .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), }, #ifdef CONFIG_NUMA { .name = "numa_stat", .open = mem_control_numa_stat_open, .mode = S_IRUGO, }, #endif }; #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP static struct cftype memsw_cgroup_files[] = { { .name = "memsw.usage_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), .read_u64 = mem_cgroup_read, .register_event = mem_cgroup_usage_register_event, .unregister_event = mem_cgroup_usage_unregister_event, }, { .name = "memsw.max_usage_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), .trigger = mem_cgroup_reset, .read_u64 = mem_cgroup_read, }, { .name = "memsw.limit_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), .write_string = mem_cgroup_write, .read_u64 = mem_cgroup_read, }, { .name = "memsw.failcnt", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), .trigger = mem_cgroup_reset, .read_u64 = mem_cgroup_read, }, }; static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) { if (!do_swap_account) return 0; return cgroup_add_files(cont, ss, memsw_cgroup_files, ARRAY_SIZE(memsw_cgroup_files)); }; #else static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) { return 0; } #endif static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) { struct mem_cgroup_per_node *pn; struct mem_cgroup_per_zone *mz; enum lru_list l; int zone, tmp = node; /* * This routine is called against possible nodes. * But it's BUG to call kmalloc() against offline node. * * TODO: this routine can waste much memory for nodes which will * never be onlined. It's better to use memory hotplug callback * function. */ if (!node_state(node, N_NORMAL_MEMORY)) tmp = -1; pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); if (!pn) return 1; for (zone = 0; zone < MAX_NR_ZONES; zone++) { mz = &pn->zoneinfo[zone]; for_each_lru(l) INIT_LIST_HEAD(&mz->lruvec.lists[l]); mz->usage_in_excess = 0; mz->on_tree = false; mz->mem = memcg; } memcg->info.nodeinfo[node] = pn; return 0; } static void free_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) { kfree(memcg->info.nodeinfo[node]); } static struct mem_cgroup *mem_cgroup_alloc(void) { struct mem_cgroup *mem; int size = sizeof(struct mem_cgroup); /* Can be very big if MAX_NUMNODES is very big */ if (size < PAGE_SIZE) mem = kzalloc(size, GFP_KERNEL); else mem = vzalloc(size); if (!mem) return NULL; mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); if (!mem->stat) goto out_free; spin_lock_init(&mem->pcp_counter_lock); return mem; out_free: if (size < PAGE_SIZE) kfree(mem); else vfree(mem); return NULL; } /* * At destroying mem_cgroup, references from swap_cgroup can remain. * (scanning all at force_empty is too costly...) * * Instead of clearing all references at force_empty, we remember * the number of reference from swap_cgroup and free mem_cgroup when * it goes down to 0. * * Removal of cgroup itself succeeds regardless of refs from swap. */ static void __mem_cgroup_free(struct mem_cgroup *memcg) { int node; mem_cgroup_remove_from_trees(memcg); free_css_id(&mem_cgroup_subsys, &memcg->css); for_each_node_state(node, N_POSSIBLE) free_mem_cgroup_per_zone_info(memcg, node); free_percpu(memcg->stat); if (sizeof(struct mem_cgroup) < PAGE_SIZE) kfree(memcg); else vfree(memcg); } static void mem_cgroup_get(struct mem_cgroup *memcg) { atomic_inc(&memcg->refcnt); } static void __mem_cgroup_put(struct mem_cgroup *memcg, int count) { if (atomic_sub_and_test(count, &memcg->refcnt)) { struct mem_cgroup *parent = parent_mem_cgroup(memcg); __mem_cgroup_free(memcg); if (parent) mem_cgroup_put(parent); } } static void mem_cgroup_put(struct mem_cgroup *memcg) { __mem_cgroup_put(memcg, 1); } /* * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. */ struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) { if (!memcg->res.parent) return NULL; return mem_cgroup_from_res_counter(memcg->res.parent, res); } EXPORT_SYMBOL(parent_mem_cgroup); #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP static void __init enable_swap_cgroup(void) { if (!mem_cgroup_disabled() && really_do_swap_account) do_swap_account = 1; } #else static void __init enable_swap_cgroup(void) { } #endif static int mem_cgroup_soft_limit_tree_init(void) { struct mem_cgroup_tree_per_node *rtpn; struct mem_cgroup_tree_per_zone *rtpz; int tmp, node, zone; for_each_node_state(node, N_POSSIBLE) { tmp = node; if (!node_state(node, N_NORMAL_MEMORY)) tmp = -1; rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, tmp); if (!rtpn) return 1; soft_limit_tree.rb_tree_per_node[node] = rtpn; for (zone = 0; zone < MAX_NR_ZONES; zone++) { rtpz = &rtpn->rb_tree_per_zone[zone]; rtpz->rb_root = RB_ROOT; spin_lock_init(&rtpz->lock); } } return 0; } static struct cgroup_subsys_state * __ref mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) { struct mem_cgroup *memcg, *parent; long error = -ENOMEM; int node; memcg = mem_cgroup_alloc(); if (!memcg) return ERR_PTR(error); for_each_node_state(node, N_POSSIBLE) if (alloc_mem_cgroup_per_zone_info(memcg, node)) goto free_out; /* root ? */ if (cont->parent == NULL) { int cpu; enable_swap_cgroup(); parent = NULL; if (mem_cgroup_soft_limit_tree_init()) goto free_out; root_mem_cgroup = memcg; for_each_possible_cpu(cpu) { struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); INIT_WORK(&stock->work, drain_local_stock); } hotcpu_notifier(memcg_cpu_hotplug_callback, 0); } else { parent = mem_cgroup_from_cont(cont->parent); memcg->use_hierarchy = parent->use_hierarchy; memcg->oom_kill_disable = parent->oom_kill_disable; } if (parent && parent->use_hierarchy) { res_counter_init(&memcg->res, &parent->res); res_counter_init(&memcg->memsw, &parent->memsw); /* * We increment refcnt of the parent to ensure that we can * safely access it on res_counter_charge/uncharge. * This refcnt will be decremented when freeing this * mem_cgroup(see mem_cgroup_put). */ mem_cgroup_get(parent); } else { res_counter_init(&memcg->res, NULL); res_counter_init(&memcg->memsw, NULL); } memcg->last_scanned_node = MAX_NUMNODES; INIT_LIST_HEAD(&memcg->oom_notify); if (parent) memcg->swappiness = mem_cgroup_swappiness(parent); atomic_set(&memcg->refcnt, 1); memcg->move_charge_at_immigrate = 0; mutex_init(&memcg->thresholds_lock); return &memcg->css; free_out: __mem_cgroup_free(memcg); return ERR_PTR(error); } static int mem_cgroup_pre_destroy(struct cgroup_subsys *ss, struct cgroup *cont) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); return mem_cgroup_force_empty(memcg, false); } static void mem_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cont) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); kmem_cgroup_destroy(ss, cont); mem_cgroup_put(memcg); } static int mem_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont) { int ret; ret = cgroup_add_files(cont, ss, mem_cgroup_files, ARRAY_SIZE(mem_cgroup_files)); if (!ret) ret = register_memsw_files(cont, ss); if (!ret) ret = register_kmem_files(cont, ss); return ret; } #ifdef CONFIG_MMU /* Handlers for move charge at task migration. */ #define PRECHARGE_COUNT_AT_ONCE 256 static int mem_cgroup_do_precharge(unsigned long count) { int ret = 0; int batch_count = PRECHARGE_COUNT_AT_ONCE; struct mem_cgroup *memcg = mc.to; if (mem_cgroup_is_root(memcg)) { mc.precharge += count; /* we don't need css_get for root */ return ret; } /* try to charge at once */ if (count > 1) { struct res_counter *dummy; /* * "memcg" cannot be under rmdir() because we've already checked * by cgroup_lock_live_cgroup() that it is not removed and we * are still under the same cgroup_mutex. So we can postpone * css_get(). */ if (res_counter_charge(&memcg->res, PAGE_SIZE * count, &dummy)) goto one_by_one; if (do_swap_account && res_counter_charge(&memcg->memsw, PAGE_SIZE * count, &dummy)) { res_counter_uncharge(&memcg->res, PAGE_SIZE * count); goto one_by_one; } mc.precharge += count; return ret; } one_by_one: /* fall back to one by one charge */ while (count--) { if (signal_pending(current)) { ret = -EINTR; break; } if (!batch_count--) { batch_count = PRECHARGE_COUNT_AT_ONCE; cond_resched(); } ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, 1, &memcg, false); if (ret || !memcg) /* mem_cgroup_clear_mc() will do uncharge later */ return -ENOMEM; mc.precharge++; } return ret; } /** * is_target_pte_for_mc - check a pte whether it is valid for move charge * @vma: the vma the pte to be checked belongs * @addr: the address corresponding to the pte to be checked * @ptent: the pte to be checked * @target: the pointer the target page or swap ent will be stored(can be NULL) * * Returns * 0(MC_TARGET_NONE): if the pte is not a target for move charge. * 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for * move charge. if @target is not NULL, the page is stored in target->page * with extra refcnt got(Callers should handle it). * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a * target for charge migration. if @target is not NULL, the entry is stored * in target->ent. * * Called with pte lock held. */ union mc_target { struct page *page; swp_entry_t ent; }; enum mc_target_type { MC_TARGET_NONE, /* not used */ MC_TARGET_PAGE, MC_TARGET_SWAP, }; static struct page *mc_handle_present_pte(struct vm_area_struct *vma, unsigned long addr, pte_t ptent) { struct page *page = vm_normal_page(vma, addr, ptent); if (!page || !page_mapped(page)) return NULL; if (PageAnon(page)) { /* we don't move shared anon */ if (!move_anon() || page_mapcount(page) > 2) return NULL; } else if (!move_file()) /* we ignore mapcount for file pages */ return NULL; if (!get_page_unless_zero(page)) return NULL; return page; } static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, unsigned long addr, pte_t ptent, swp_entry_t *entry) { int usage_count; struct page *page = NULL; swp_entry_t ent = pte_to_swp_entry(ptent); if (!move_anon() || non_swap_entry(ent)) return NULL; usage_count = mem_cgroup_count_swap_user(ent, &page); if (usage_count > 1) { /* we don't move shared anon */ if (page) put_page(page); return NULL; } if (do_swap_account) entry->val = ent.val; return page; } static struct page *mc_handle_file_pte(struct vm_area_struct *vma, unsigned long addr, pte_t ptent, swp_entry_t *entry) { struct page *page = NULL; struct inode *inode; struct address_space *mapping; pgoff_t pgoff; if (!vma->vm_file) /* anonymous vma */ return NULL; if (!move_file()) return NULL; inode = vma->vm_file->f_path.dentry->d_inode; mapping = vma->vm_file->f_mapping; if (pte_none(ptent)) pgoff = linear_page_index(vma, addr); else /* pte_file(ptent) is true */ pgoff = pte_to_pgoff(ptent); /* page is moved even if it's not RSS of this task(page-faulted). */ page = find_get_page(mapping, pgoff); #ifdef CONFIG_SWAP /* shmem/tmpfs may report page out on swap: account for that too. */ if (radix_tree_exceptional_entry(page)) { swp_entry_t swap = radix_to_swp_entry(page); if (do_swap_account) *entry = swap; page = find_get_page(&swapper_space, swap.val); } #endif return page; } static int is_target_pte_for_mc(struct vm_area_struct *vma, unsigned long addr, pte_t ptent, union mc_target *target) { struct page *page = NULL; struct page_cgroup *pc; int ret = 0; swp_entry_t ent = { .val = 0 }; if (pte_present(ptent)) page = mc_handle_present_pte(vma, addr, ptent); else if (is_swap_pte(ptent)) page = mc_handle_swap_pte(vma, addr, ptent, &ent); else if (pte_none(ptent) || pte_file(ptent)) page = mc_handle_file_pte(vma, addr, ptent, &ent); if (!page && !ent.val) return 0; if (page) { pc = lookup_page_cgroup(page); /* * Do only loose check w/o page_cgroup lock. * mem_cgroup_move_account() checks the pc is valid or not under * the lock. */ if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { ret = MC_TARGET_PAGE; if (target) target->page = page; } if (!ret || !target) put_page(page); } /* There is a swap entry and a page doesn't exist or isn't charged */ if (ent.val && !ret && css_id(&mc.from->css) == lookup_swap_cgroup(ent)) { ret = MC_TARGET_SWAP; if (target) target->ent = ent; } return ret; } static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct mm_walk *walk) { struct vm_area_struct *vma = walk->private; pte_t *pte; spinlock_t *ptl; split_huge_page_pmd(walk->mm, pmd); pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); for (; addr != end; pte++, addr += PAGE_SIZE) if (is_target_pte_for_mc(vma, addr, *pte, NULL)) mc.precharge++; /* increment precharge temporarily */ pte_unmap_unlock(pte - 1, ptl); cond_resched(); return 0; } static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) { unsigned long precharge; struct vm_area_struct *vma; down_read(&mm->mmap_sem); for (vma = mm->mmap; vma; vma = vma->vm_next) { struct mm_walk mem_cgroup_count_precharge_walk = { .pmd_entry = mem_cgroup_count_precharge_pte_range, .mm = mm, .private = vma, }; if (is_vm_hugetlb_page(vma)) continue; walk_page_range(vma->vm_start, vma->vm_end, &mem_cgroup_count_precharge_walk); } up_read(&mm->mmap_sem); precharge = mc.precharge; mc.precharge = 0; return precharge; } static int mem_cgroup_precharge_mc(struct mm_struct *mm) { unsigned long precharge = mem_cgroup_count_precharge(mm); VM_BUG_ON(mc.moving_task); mc.moving_task = current; return mem_cgroup_do_precharge(precharge); } /* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */ static void __mem_cgroup_clear_mc(void) { struct mem_cgroup *from = mc.from; struct mem_cgroup *to = mc.to; /* we must uncharge all the leftover precharges from mc.to */ if (mc.precharge) { __mem_cgroup_cancel_charge(mc.to, mc.precharge); mc.precharge = 0; } /* * we didn't uncharge from mc.from at mem_cgroup_move_account(), so * we must uncharge here. */ if (mc.moved_charge) { __mem_cgroup_cancel_charge(mc.from, mc.moved_charge); mc.moved_charge = 0; } /* we must fixup refcnts and charges */ if (mc.moved_swap) { /* uncharge swap account from the old cgroup */ if (!mem_cgroup_is_root(mc.from)) res_counter_uncharge(&mc.from->memsw, PAGE_SIZE * mc.moved_swap); __mem_cgroup_put(mc.from, mc.moved_swap); if (!mem_cgroup_is_root(mc.to)) { /* * we charged both to->res and to->memsw, so we should * uncharge to->res. */ res_counter_uncharge(&mc.to->res, PAGE_SIZE * mc.moved_swap); } /* we've already done mem_cgroup_get(mc.to) */ mc.moved_swap = 0; } memcg_oom_recover(from); memcg_oom_recover(to); wake_up_all(&mc.waitq); } static void mem_cgroup_clear_mc(void) { struct mem_cgroup *from = mc.from; /* * we must clear moving_task before waking up waiters at the end of * task migration. */ mc.moving_task = NULL; __mem_cgroup_clear_mc(); spin_lock(&mc.lock); mc.from = NULL; mc.to = NULL; spin_unlock(&mc.lock); mem_cgroup_end_move(from); } static int mem_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgroup, struct cgroup_taskset *tset) { struct task_struct *p = cgroup_taskset_first(tset); int ret = 0; struct mem_cgroup *memcg = mem_cgroup_from_cont(cgroup); if (memcg->move_charge_at_immigrate) { struct mm_struct *mm; struct mem_cgroup *from = mem_cgroup_from_task(p); VM_BUG_ON(from == memcg); mm = get_task_mm(p); if (!mm) return 0; /* We move charges only when we move a owner of the mm */ if (mm->owner == p) { VM_BUG_ON(mc.from); VM_BUG_ON(mc.to); VM_BUG_ON(mc.precharge); VM_BUG_ON(mc.moved_charge); VM_BUG_ON(mc.moved_swap); mem_cgroup_start_move(from); spin_lock(&mc.lock); mc.from = from; mc.to = memcg; spin_unlock(&mc.lock); /* We set mc.moving_task later */ ret = mem_cgroup_precharge_mc(mm); if (ret) mem_cgroup_clear_mc(); } mmput(mm); } return ret; } static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, struct cgroup *cgroup, struct cgroup_taskset *tset) { mem_cgroup_clear_mc(); } static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct mm_walk *walk) { int ret = 0; struct vm_area_struct *vma = walk->private; pte_t *pte; spinlock_t *ptl; split_huge_page_pmd(walk->mm, pmd); retry: pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); for (; addr != end; addr += PAGE_SIZE) { pte_t ptent = *(pte++); union mc_target target; int type; struct page *page; struct page_cgroup *pc; swp_entry_t ent; if (!mc.precharge) break; type = is_target_pte_for_mc(vma, addr, ptent, &target); switch (type) { case MC_TARGET_PAGE: page = target.page; if (isolate_lru_page(page)) goto put; pc = lookup_page_cgroup(page); if (!mem_cgroup_move_account(page, 1, pc, mc.from, mc.to, false)) { mc.precharge--; /* we uncharge from mc.from later. */ mc.moved_charge++; } putback_lru_page(page); put: /* is_target_pte_for_mc() gets the page */ put_page(page); break; case MC_TARGET_SWAP: ent = target.ent; if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to, false)) { mc.precharge--; /* we fixup refcnts and charges later. */ mc.moved_swap++; } break; default: break; } } pte_unmap_unlock(pte - 1, ptl); cond_resched(); if (addr != end) { /* * We have consumed all precharges we got in can_attach(). * We try charge one by one, but don't do any additional * charges to mc.to if we have failed in charge once in attach() * phase. */ ret = mem_cgroup_do_precharge(1); if (!ret) goto retry; } return ret; } static void mem_cgroup_move_charge(struct mm_struct *mm) { struct vm_area_struct *vma; lru_add_drain_all(); retry: if (unlikely(!down_read_trylock(&mm->mmap_sem))) { /* * Someone who are holding the mmap_sem might be waiting in * waitq. So we cancel all extra charges, wake up all waiters, * and retry. Because we cancel precharges, we might not be able * to move enough charges, but moving charge is a best-effort * feature anyway, so it wouldn't be a big problem. */ __mem_cgroup_clear_mc(); cond_resched(); goto retry; } for (vma = mm->mmap; vma; vma = vma->vm_next) { int ret; struct mm_walk mem_cgroup_move_charge_walk = { .pmd_entry = mem_cgroup_move_charge_pte_range, .mm = mm, .private = vma, }; if (is_vm_hugetlb_page(vma)) continue; ret = walk_page_range(vma->vm_start, vma->vm_end, &mem_cgroup_move_charge_walk); if (ret) /* * means we have consumed all precharges and failed in * doing additional charge. Just abandon here. */ break; } up_read(&mm->mmap_sem); } static void mem_cgroup_move_task(struct cgroup_subsys *ss, struct cgroup *cont, struct cgroup_taskset *tset) { struct task_struct *p = cgroup_taskset_first(tset); struct mm_struct *mm = get_task_mm(p); if (mm) { if (mc.to) mem_cgroup_move_charge(mm); put_swap_token(mm); mmput(mm); } if (mc.to) mem_cgroup_clear_mc(); } #else /* !CONFIG_MMU */ static int mem_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgroup, struct cgroup_taskset *tset) { return 0; } static void mem_cgroup_cancel_attach(struct cgroup_subsys *ss, struct cgroup *cgroup, struct cgroup_taskset *tset) { } static void mem_cgroup_move_task(struct cgroup_subsys *ss, struct cgroup *cont, struct cgroup_taskset *tset) { } #endif struct cgroup_subsys mem_cgroup_subsys = { .name = "memory", .subsys_id = mem_cgroup_subsys_id, .create = mem_cgroup_create, .pre_destroy = mem_cgroup_pre_destroy, .destroy = mem_cgroup_destroy, .populate = mem_cgroup_populate, .can_attach = mem_cgroup_can_attach, .cancel_attach = mem_cgroup_cancel_attach, .attach = mem_cgroup_move_task, .early_init = 0, .use_id = 1, }; #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP static int __init enable_swap_account(char *s) { /* consider enabled if no parameter or 1 is given */ if (!strcmp(s, "1")) really_do_swap_account = 1; else if (!strcmp(s, "0")) really_do_swap_account = 0; return 1; } __setup("swapaccount=", enable_swap_account); #endif