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* fix possible null ptr deref in kallsyms_lookupKyle McMartin2007-05-30
| | | | | | | | ugh, this function gets called by our unwinder. recursive backtrace for the win... bisection to find this one was "fun." Signed-off-by: Kyle McMartin <kyle@parisc-linux.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* NOHZ: prevent multiplication overflow - stop timer for huge timeoutsThomas Gleixner2007-05-29
| | | | | | | | | | | | | | | | | | | | | | | get_next_timer_interrupt() returns a delta of (LONG_MAX > 1) in case there is no timer pending. On 64 bit machines this results in a multiplication overflow in tick_nohz_stop_sched_tick(). Reported by: Dave Miller <davem@davemloft.net> Make the return value a constant and limit the return value to a 32 bit value. When the max timeout value is returned, we can safely stop the tick timer device. The max jiffies delta results in a 12 days timeout for HZ=1000. In the long term the get_next_timer_interrupt() code needs to be reworked to return ktime instead of jiffies, but we have to wait until the last users of the original NO_IDLE_HZ code are converted. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Fix crash with irqpoll due to the IRQF_IRQPOLL flag testingLinus Torvalds2007-05-24
| | | | | | | | | | | | | | | | | | | With irqpoll enabled, trying to test the IRQF_IRQPOLL flag in the actions would cause a NULL pointer dereference if no action was installed (for example, the driver might have been unloaded with interrupts still pending). So be a bit more careful about testing the flag by making sure to test for that case. (The actual _change_ is trivial, the patch is more than a one-liner because I rewrote the testing to also be much more readable. Original (discarded) bugfix by Bernhard Walle. Cc: Bernhard Walle <bwalle@suse.de> Tested-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Prevent going idle with softirq pendingThomas Gleixner2007-05-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The NOHZ patch contains a check for softirqs pending when a CPU goes idle. The BUG is unrelated to NOHZ, it just was made visible by the NOHZ patch. The BUG showed up mainly on P4 / hyperthreading enabled machines which lead the investigations into the wrong direction in the first place. The real cause is in cond_resched_softirq(): cond_resched_softirq() is enabling softirqs without invoking the softirq daemon when softirqs are pending. This leads to the warning message in the NOHZ idle code: t1 runs softirq disabled code on CPU#0 interrupt happens, softirq is raised, but deferred (softirqs disabled) t1 calls cond_resched_softirq() enables softirqs via _local_bh_enable() calls schedule() t2 runs t1 is migrated to CPU#1 t2 is done and invokes idle() NOHZ detects the pending softirq Fix: change _local_bh_enable() to local_bh_enable() so the softirq daemon is invoked. Thanks to Anant Nitya for debugging this with great patience ! Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* power: Fix sizeof(PAGE_SIZE) typoOGAWA Hirofumi2007-05-23
| | | | | | | | | | | | Fix sizeof(PAGE_SIZE) typo. It should be just PAGE_SIZE for zeroing the swsusp_header. Signed-off-by: OGAWA Hirofumi <hogawa@miraclelinux.com> Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* simplify cleanup_workqueue_thread()Oleg Nesterov2007-05-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | cleanup_workqueue_thread() and cwq_should_stop() are overcomplicated. Convert the code to use kthread_should_stop/kthread_stop as was suggested by Gautham and Srivatsa. In particular this patch removes the (unlikely) busy-wait loop from the exit path, it was a temporary and ugly kludge (if not a bug). Note: the current code was designed to solve another old problem: work->func can't share locks with hotplug callbacks. I think this could be done, see http://marc.info/?l=linux-kernel&m=116905366428633 but this needs some more complications to preserve CPU affinity of cwq->thread during cpu_up(). A freezer-based hotplug looks more appealing. [akpm@linux-foundation.org: make it more tolerant of gcc borkenness] Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Zilvinas Valinskas <zilvinas@wilibox.com> Cc: Gautham R Shenoy <ego@in.ibm.com> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* recalc_sigpending_tsk fixesRoland McGrath2007-05-23
| | | | | | | | | | | | | | | | | | | Steve Hawkes discovered a problem where recalc_sigpending_tsk was called in do_sigaction but no signal_wake_up call was made, preventing later signals from waking up blocked threads with TIF_SIGPENDING already set. In fact, the few other calls to recalc_sigpending_tsk outside the signals code are also subject to this problem in other race conditions. This change makes recalc_sigpending_tsk private to the signals code. It changes the outside calls, as well as do_sigaction, to use the new recalc_sigpending_and_wake instead. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: <Steve.Hawkes@motorola.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* NOHZ: Rate limit the local softirq pending warning outputThomas Gleixner2007-05-23
| | | | | | | | | | | The warning in the NOHZ code, which triggers when a CPU goes idle with softirqs pending can fill up the logs quite quickly. Rate limit the output until we found the root cause of that problem. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Ignore bogus ACPI info for offline CPUsThomas Gleixner2007-05-23
| | | | | | | | | | | | | | | Booting a SMP kernel with maxcpus=1 on a SMP system leads to a hard hang, because ACPI ignores the maxcpus setting and sends timer broadcast info for the offline CPUs. This results in a stuck for ever call to smp_call_function_single() on an offline CPU. Ignore the bogus information and print a kernel error to remind ACPI folks to fix it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* freezer: move frozen_process() to kernel/power/process.cGautham R Shenoy2007-05-23
| | | | | | | | | | | | | | | | Other than refrigerator, no one else calls frozen_process(). So move it from include/linux/freezer.h to kernel/power/process.c. Also, since a task can be marked as frozen by itself, we don't need to pass the (struct task_struct *p) parameter to frozen_process(). Signed-off-by: Gautham R Shenoy <ego@in.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* freezer: fix kthread_create vs freezer theoretical raceOleg Nesterov2007-05-23
| | | | | | | | | | | | | | | | kthread() sleeps in TASK_INTERRUPTIBLE state waiting for the first wakeup. In theory, this wakeup may come from freeze_process()->signal_wake_up(), so the task can disappear even before kthread_create() sets its ->comm. Change kthread() to use TASK_UNINTERRUPTIBLE. [akpm@linux-foundation.org: s/BUG_ON/WARN_ON+recover] Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Gautham R Shenoy <ego@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* freezer: take kernel_execve into considerationRafael J. Wysocki2007-05-23
| | | | | | | | | | | | | | | | | Kernel threads can become userland processes by calling kernel_execve(). In particular, this may happen right after the try_to_freeze_tasks() called with FREEZER_USER_SPACE has returned, so try_to_freeze_tasks() needs to take userspace processes into consideration even if it is called with FREEZER_KERNEL_THREADS. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Cc: Gautham R Shenoy <ego@in.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* freezer: fix vfork problemRafael J. Wysocki2007-05-23
| | | | | | | | | | | | | | | | | | | Currently try_to_freeze_tasks() has to wait until all of the vforked processes exit and for this reason every user can make it fail. To fix this problem we can introduce the additional process flag PF_FREEZER_SKIP to be used by tasks that do not want to be counted as freezable by the freezer and want to have TIF_FREEZE set nevertheless. Then, this flag can be set by tasks using sys_vfork() before they call wait_for_completion(&vfork) and cleared after they have woken up. After clearing it, the tasks should call try_to_freeze() as soon as possible. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Gautham R Shenoy <ego@in.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* freezer: close potential race between refrigerator and thaw_tasksRafael J. Wysocki2007-05-23
| | | | | | | | | | | | | | | | | | | | | If the freezing of tasks fails and a task is preempted in refrigerator() before calling frozen_process(), then thaw_tasks() may run before this task is frozen. In that case the task will freeze and no one will thaw it. To fix this race we can call freezing(current) in refrigerator() along with frozen_process(current) under the task_lock() which also should be taken in the error path of try_to_freeze_tasks() as well as in thaw_process(). Moreover, if thaw_process() additionally clears TIF_FREEZE for tasks that are not frozen, we can be sure that all tasks are thawed and there are no pending "freeze" requests after thaw_tasks() has run. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Cc: Gautham R Shenoy <ego@in.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Detach sched.h from mm.hAlexey Dobriyan2007-05-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* swsusp: fix sysfs interfaceRafael J. Wysocki2007-05-17
| | | | | | | | | | | | | | | The sysfs files /sys/power/disk and /sys/power/state do not work as documented, since they allow the user to write only a few initial characters of the input string to trigger the option (eg. 'echo pl > /sys/power/disk' activates the platform mode of hibernation). Fix it. Special thanks to Peter Moulder <Peter.Moulder@infotech.monash.edu.au> for pointing out the problem. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* make sysctl/kernel/core_pattern and fs/exec.c agree on maximum core filename ↵Dan Aloni2007-05-17
| | | | | | | | | | | | | size Make sysctl/kernel/core_pattern and fs/exec.c agree on maximum core filename size and change it to 128, so that extensive patterns such as '/local/cores/%e-%h-%s-%t-%p.core' won't result in truncated filename generation. Signed-off-by: Dan Aloni <da-x@monatomic.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Remove SLAB_CTOR_CONSTRUCTORChristoph Lameter2007-05-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | SLAB_CTOR_CONSTRUCTOR is always specified. No point in checking it. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: David Howells <dhowells@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven French <sfrench@us.ibm.com> Cc: Michael Halcrow <mhalcrow@us.ibm.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Dave Kleikamp <shaggy@austin.ibm.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Anton Altaparmakov <aia21@cantab.net> Cc: Mark Fasheh <mark.fasheh@oracle.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Jan Kara <jack@ucw.cz> Cc: David Chinner <dgc@sgi.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Fix ACPI suspend / device suspend ordering problemLinus Torvalds2007-05-16
| | | | | | | | | | | | | | | | | | | | | | | | | | In commit e3c7db621bed4afb8e231cb005057f2feb5db557 we fixed the resume ordering, so that the ACPI low-level resume code was called before the actual driver resume was called. However, that broke the nesting logic of suspend and resume, and we continued to suspend the devices _after_ we the ACPI device suspend code was called. That resulted in us saving PCI state for devices that had already been changed by ACPI, and in some cases disabled entirely (causing the PCI save_state to be all-ones). Which in turn caused the wrong state to be written back on resume. This moves the ACPI device suspend to after the device model per-device suspend() calls. This fixes the bogus state save. Thanks to Lukáš Hejtmánek for testing. Acked-by: Lukas Hejtmanek <xhejtman@ics.muni.cz> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg KH <greg@kroah.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* audit_match_signal() and friends are used only if CONFIG_AUDITSYSCALL is setAl Viro2007-05-15
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* clocksource: fix lock order in the resume pathThomas Gleixner2007-05-15
| | | | | | | | | | | | | lockdep complains about the lock nesting of clocksource and watchdog lock in the resume path. Change the resume marker to a bit operation and remove the lock from this path. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* timekeeping fix patch got mis-appliedThomas Gleixner2007-05-14
| | | | | | | | | | | The time keeping code move to kernel/time/timekeeping.c broke the clocksource resume logic patch, which got applied to the old file by a fuzzy application. Fix it up and move the clocksource_resume() call to the appropriate place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [ tssk, tssk, everybody should use --fuzz=0 ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* compat signalfd and timerfd are cond syscallsHeiko Carstens2007-05-12
| | | | | | | | | | Add missing cond_syscall statements for compat_sys_signalfd and compat_sys_timerfd. Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'release' of ↵Linus Torvalds2007-05-11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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] Quicklist support for IA64 [IA64] fix Kprobes reentrancy [IA64] SN: validate smp_affinity mask on intr redirect [IA64] drivers/char/snsc_event.c:206: warning: unused variable `p' [IA64] mca.c:121: warning: 'cpe_poll_timer' defined but not used [IA64] Fix - Section mismatch: reference to .init.data:mvec_name [IA64] more warning cleanups [IA64] Wire up epoll_pwait and utimensat [IA64] Fix warnings resulting from type-checking in dev_dbg() [IA64] typo s/kenrel/kernel/
| * [IA64] SN: validate smp_affinity mask on intr redirectJohn Keller2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | On SN, only allow one bit to be set in the smp_affinty mask when redirecting an interrupt. Currently setting multiple bits is allowed, but only the first bit is used in determining the CPU to redirect to. This has caused confusion among some customers. [akpm@linux-foundation.org: fixes] Signed-off-by: John Keller <jpk@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
* | Merge branch 'audit.b38' of ↵Linus Torvalds2007-05-11
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current * 'audit.b38' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current: [PATCH] Abnormal End of Processes [PATCH] match audit name data [PATCH] complete message queue auditing [PATCH] audit inode for all xattr syscalls [PATCH] initialize name osid [PATCH] audit signal recipients [PATCH] add SIGNAL syscall class (v3) [PATCH] auditing ptrace
| * | [PATCH] Abnormal End of ProcessesSteve Grubb2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hi, I have been working on some code that detects abnormal events based on audit system events. One kind of event that we currently have no visibility for is when a program terminates due to segfault - which should never happen on a production machine. And if it did, you'd want to investigate it. Attached is a patch that collects these events and sends them into the audit system. Signed-off-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] match audit name dataAmy Griffis2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | Make more effort to detect previously collected names, so we don't log multiple PATH records for a single filesystem object. Add audit_inc_name_count() to reduce duplicate code. Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] complete message queue auditingAmy Griffis2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Handle the edge cases for POSIX message queue auditing. Collect inode info when opening an existing mq, and for send/receive operations. Remove audit_inode_update() as it has really evolved into the equivalent of audit_inode(). Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] initialize name osidAmy Griffis2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | Audit contexts can be reused, so initialize a name's osid to the default in audit_getname(). This ensures we don't log a bogus object label when no inode data is collected for a name. Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] audit signal recipientsAmy Griffis2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When auditing syscalls that send signals, log the pid and security context for each target process. Optimize the data collection by adding a counter for signal-related rules, and avoiding allocating an aux struct unless we have more than one target process. For process groups, collect pid/context data in blocks of 16. Move the audit_signal_info() hook up in check_kill_permission() so we audit attempts where permission is denied. Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] auditing ptraceAl Viro2007-05-11
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | signal/timer/event: eventfd coreDavide Libenzi2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a very simple and light file descriptor, that can be used as event wait/dispatch by userspace (both wait and dispatch) and by the kernel (dispatch only). It can be used instead of pipe(2) in all cases where those would simply be used to signal events. Their kernel overhead is much lower than pipes, and they do not consume two fds. When used in the kernel, it can offer an fd-bridge to enable, for example, functionalities like KAIO or syslets/threadlets to signal to an fd the completion of certain operations. But more in general, an eventfd can be used by the kernel to signal readiness, in a POSIX poll/select way, of interfaces that would otherwise be incompatible with it. The API is: int eventfd(unsigned int count); The eventfd API accepts an initial "count" parameter, and returns an eventfd fd. It supports poll(2) (POLLIN, POLLOUT, POLLERR), read(2) and write(2). The POLLIN flag is raised when the internal counter is greater than zero. The POLLOUT flag is raised when at least a value of "1" can be written to the internal counter. The POLLERR flag is raised when an overflow in the counter value is detected. The write(2) operation can never overflow the counter, since it blocks (unless O_NONBLOCK is set, in which case -EAGAIN is returned). But the eventfd_signal() function can do it, since it's supposed to not sleep during its operation. The read(2) function reads the __u64 counter value, and reset the internal value to zero. If the value read is equal to (__u64) -1, an overflow happened on the internal counter (due to 2^64 eventfd_signal() posts that has never been retired - unlickely, but possible). The write(2) call writes an __u64 count value, and adds it to the current counter. The eventfd fd supports O_NONBLOCK also. On the kernel side, we have: struct file *eventfd_fget(int fd); int eventfd_signal(struct file *file, unsigned int n); The eventfd_fget() should be called to get a struct file* from an eventfd fd (this is an fget() + check of f_op being an eventfd fops pointer). The kernel can then call eventfd_signal() every time it wants to post an event to userspace. The eventfd_signal() function can be called from any context. An eventfd() simple test and bench is available here: http://www.xmailserver.org/eventfd-bench.c This is the eventfd-based version of pipetest-4 (pipe(2) based): http://www.xmailserver.org/pipetest-4.c Not that performance matters much in the eventfd case, but eventfd-bench shows almost as double as performance than pipetest-4. [akpm@linux-foundation.org: fix i386 build] [akpm@linux-foundation.org: add sys_eventfd to sys_ni.c] Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | signal/timer/event: timerfd compat codeDavide Libenzi2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | This patch implements the necessary compat code for the timerfd system call. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | signal/timer/event: timerfd coreDavide Libenzi2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces a new system call for timers events delivered though file descriptors. This allows timer event to be used with standard POSIX poll(2), select(2) and read(2). As a consequence of supporting the Linux f_op->poll subsystem, they can be used with epoll(2) too. The system call is defined as: int timerfd(int ufd, int clockid, int flags, const struct itimerspec *utmr); The "ufd" parameter allows for re-use (re-programming) of an existing timerfd w/out going through the close/open cycle (same as signalfd). If "ufd" is -1, s new file descriptor will be created, otherwise the existing "ufd" will be re-programmed. The "clockid" parameter is either CLOCK_MONOTONIC or CLOCK_REALTIME. The time specified in the "utmr->it_value" parameter is the expiry time for the timer. If the TFD_TIMER_ABSTIME flag is set in "flags", this is an absolute time, otherwise it's a relative time. If the time specified in the "utmr->it_interval" is not zero (.tv_sec == 0, tv_nsec == 0), this is the period at which the following ticks should be generated. The "utmr->it_interval" should be set to zero if only one tick is requested. Setting the "utmr->it_value" to zero will disable the timer, or will create a timerfd without the timer enabled. The function returns the new (or same, in case "ufd" is a valid timerfd descriptor) file, or -1 in case of error. As stated before, the timerfd file descriptor supports poll(2), select(2) and epoll(2). When a timer event happened on the timerfd, a POLLIN mask will be returned. The read(2) call can be used, and it will return a u32 variable holding the number of "ticks" that happened on the interface since the last call to read(2). The read(2) call supportes the O_NONBLOCK flag too, and EAGAIN will be returned if no ticks happened. A quick test program, shows timerfd working correctly on my amd64 box: http://www.xmailserver.org/timerfd-test.c [akpm@linux-foundation.org: add sys_timerfd to sys_ni.c] Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | signal/timer/event: signalfd coreDavide Libenzi2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch series implements the new signalfd() system call. I took part of the original Linus code (and you know how badly it can be broken :), and I added even more breakage ;) Signals are fetched from the same signal queue used by the process, so signalfd will compete with standard kernel delivery in dequeue_signal(). If you want to reliably fetch signals on the signalfd file, you need to block them with sigprocmask(SIG_BLOCK). This seems to be working fine on my Dual Opteron machine. I made a quick test program for it: http://www.xmailserver.org/signafd-test.c The signalfd() system call implements signal delivery into a file descriptor receiver. The signalfd file descriptor if created with the following API: int signalfd(int ufd, const sigset_t *mask, size_t masksize); The "ufd" parameter allows to change an existing signalfd sigmask, w/out going to close/create cycle (Linus idea). Use "ufd" == -1 if you want a brand new signalfd file. The "mask" allows to specify the signal mask of signals that we are interested in. The "masksize" parameter is the size of "mask". The signalfd fd supports the poll(2) and read(2) system calls. The poll(2) will return POLLIN when signals are available to be dequeued. As a direct consequence of supporting the Linux poll subsystem, the signalfd fd can use used together with epoll(2) too. The read(2) system call will return a "struct signalfd_siginfo" structure in the userspace supplied buffer. The return value is the number of bytes copied in the supplied buffer, or -1 in case of error. The read(2) call can also return 0, in case the sighand structure to which the signalfd was attached, has been orphaned. The O_NONBLOCK flag is also supported, and read(2) will return -EAGAIN in case no signal is available. If the size of the buffer passed to read(2) is lower than sizeof(struct signalfd_siginfo), -EINVAL is returned. A read from the signalfd can also return -ERESTARTSYS in case a signal hits the process. The format of the struct signalfd_siginfo is, and the valid fields depends of the (->code & __SI_MASK) value, in the same way a struct siginfo would: struct signalfd_siginfo { __u32 signo; /* si_signo */ __s32 err; /* si_errno */ __s32 code; /* si_code */ __u32 pid; /* si_pid */ __u32 uid; /* si_uid */ __s32 fd; /* si_fd */ __u32 tid; /* si_fd */ __u32 band; /* si_band */ __u32 overrun; /* si_overrun */ __u32 trapno; /* si_trapno */ __s32 status; /* si_status */ __s32 svint; /* si_int */ __u64 svptr; /* si_ptr */ __u64 utime; /* si_utime */ __u64 stime; /* si_stime */ __u64 addr; /* si_addr */ }; [akpm@linux-foundation.org: fix signalfd_copyinfo() on i386] Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Use task_pgrp() task_session() in copy_process()Sukadev Bhattiprolu2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use task_pgrp() and task_session() in copy_process(), and avoid find_pid() call when attaching the task to its process group and session. Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: <containers@lists.osdl.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Use struct pid parameter in copy_process()Sukadev Bhattiprolu2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modify copy_process() to take a struct pid * parameter instead of a pid_t. This simplifies the code a bit and also avoids having to call find_pid() to convert the pid_t to a struct pid. Changelog: - Fixed Badari Pulavarty's comments and passed in &init_struct_pid from fork_idle(). - Fixed Eric Biederman's comments and simplified this patch and used a new patch to remove the likely(pid) check. Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: <containers@lists.osdl.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | statically initialize struct pid for swapperSukadev Bhattiprolu2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Statically initialize a struct pid for the swapper process (pid_t == 0) and attach it to init_task. This is needed so task_pid(), task_pgrp() and task_session() interfaces work on the swapper process also. Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: <containers@lists.osdl.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | attach_pid() with struct pid parameterSukadev Bhattiprolu2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | attach_pid() currently takes a pid_t and then uses find_pid() to find the corresponding struct pid. Sometimes we already have the struct pid. We can then skip find_pid() if attach_pid() were to take a struct pid parameter. Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: <containers@lists.osdl.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | use defines in sys_getpriority/sys_setpriorityDaniel Walker2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switch to the defines for these two checks, instead of hard coding the values. [akpm@linux-foundation.org: add missing include] Signed-off-by: Daniel Walker <dwalker@mvista.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | stop_machine() now uses hard_irq_disableBenjamin Herrenschmidt2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a call to hard_irq_disable() to stop_machine so that we make sure IRQs are really disabled and not only lazy-disabled on archs like powerpc as some users of stop_machine() may rely on that. [akpm@linux-foundation.org: build fix] Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | getrusage(): fill ru_inblock and ru_oublock fields if possibleEric Dumazet2007-05-11
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If CONFIG_TASK_IO_ACCOUNTING is defined, we update io accounting counters for each task. This patch permits reporting of values using the well known getrusage() syscall, filling ru_inblock and ru_oublock instead of null values. As TASK_IO_ACCOUNTING currently counts bytes counts, we approximate blocks count doing : nr_blocks = nr_bytes / 512 Example of use : ---------------------- After patch is applied, /usr/bin/time command can now give a good approximation of IO that the process had to do. $ /usr/bin/time grep tototo /usr/include/* Command exited with non-zero status 1 0.00user 0.02system 0:02.11elapsed 1%CPU (0avgtext+0avgdata 0maxresident)k 24288inputs+0outputs (0major+259minor)pagefaults 0swaps $ /usr/bin/time dd if=/dev/zero of=/tmp/testfile count=1000 1000+0 enregistrements lus 1000+0 enregistrements écrits 512000 octets (512 kB) copiés, 0,00326601 seconde, 157 MB/s 0.00user 0.00system 0:00.00elapsed 80%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+3000outputs (0major+299minor)pagefaults 0swaps Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* / timer: revert parenthesis fix in tbase_get_deferrable() etcakpm@linux-foundation.org2007-05-10
|/ | | | | | | | | | | | | | | | | | | | On 09-05-2007 21:10, Pallipadi, Venkatesh wrote: ... > On a 64 bit system, converting pointer to int causes unnecessary > compiler warning, and intermediate long conversion was to avoid that. > I will have to rephrase my comment to remove 32 bit value and use int, > as that is what the function returns. So, this patch reverts all changes done by my previous patch. I apologize for my wrong comment about "logical error" here. Cc: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Jarek Poplawski <jarkao2@o2.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'master' of ↵Linus Torvalds2007-05-09
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: [POWERPC] Further fixes for the removal of 4level-fixup hack from ppc32 [POWERPC] EEH: log all PCI-X and PCI-E AER registers [POWERPC] EEH: capture and log pci state on error [POWERPC] EEH: Split up long error msg [POWERPC] EEH: log error only after driver notification. [POWERPC] fsl_soc: Make mac_addr const in fs_enet_of_init(). [POWERPC] Don't use SLAB/SLUB for PTE pages [POWERPC] Spufs support for 64K LS mappings on 4K kernels [POWERPC] Add ability to 4K kernel to hash in 64K pages [POWERPC] Introduce address space "slices" [POWERPC] Small fixes & cleanups in segment page size demotion [POWERPC] iSeries: Make HVC_ISERIES the default [POWERPC] iSeries: suppress build warning in lparmap.c [POWERPC] Mark pages that don't exist as nosave [POWERPC] swsusp: Introduce register_nosave_region_late
| * [POWERPC] swsusp: Introduce register_nosave_region_lateJohannes Berg2007-05-09
| | | | | | | | | | | | | | | | | | | | This patch introduces a new register_nosave_region_late function that can be called from initcalls when register_nosave_region can no longer be used because it uses bootmem. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Paul Mackerras <paulus@samba.org>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds2007-05-09
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits) sound: convert "sound" subdirectory to UTF-8 MAINTAINERS: Add cxacru website/mailing list include files: convert "include" subdirectory to UTF-8 general: convert "kernel" subdirectory to UTF-8 documentation: convert the Documentation directory to UTF-8 Convert the toplevel files CREDITS and MAINTAINERS to UTF-8. remove broken URLs from net drivers' output Magic number prefix consistency change to Documentation/magic-number.txt trivial: s/i_sem /i_mutex/ fix file specification in comments drivers/base/platform.c: fix small typo in doc misc doc and kconfig typos Remove obsolete fat_cvf help text Fix occurrences of "the the " Fix minor typoes in kernel/module.c Kconfig: Remove reference to external mqueue library Kconfig: A couple of grammatical fixes in arch/i386/Kconfig Correct comments in genrtc.c to refer to correct /proc file. Fix more "deprecated" spellos. Fix "deprecated" typoes. ... Fix trivial comment conflict in kernel/relay.c.
| * | general: convert "kernel" subdirectory to UTF-8John Anthony Kazos Jr2007-05-09
| | | | | | | | | | | | | | | | | | | | | | | | Convert the "kernel" subdirectory of the tree to UTF-8. The only file modified is <kernel/sys.c>. Signed-off-by: John Anthony Kazos Jr. <jakj@j-a-k-j.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
| * | Fix occurrences of "the the "Michael Opdenacker2007-05-09
| | | | | | | | | | | | | | | Signed-off-by: Michael Opdenacker <michael@free-electrons.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
| * | Fix minor typoes in kernel/module.cRobert P. J. Day2007-05-09
| | | | | | | | | | | | | | | | | | | | | Fix minor (comment) typoes in kernel/module.c. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>