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* IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells2006-10-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
* IRQ: Typedef the IRQ handler function typeDavid Howells2006-10-05
| | | | | | | Typedef the IRQ handler function type. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1356d1e5fd256997e3d3dce0777ab787d0515c7a commit)
* IRQ: Typedef the IRQ flow handler function typeDavid Howells2006-10-05
| | | | | | | Typedef the IRQ flow handler function type. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 8e973fbdf5716b93a0a8c0365be33a31ca0fa351 commit)
* Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/confighLinus Torvalds2006-10-04
|\ | | | | | | | | | | | | | | * master.kernel.org:/pub/scm/linux/kernel/git/davej/configh: Remove all inclusions of <linux/config.h> Manually resolved trivial path conflicts due to removed files in the sound/oss/ subdirectory.
| * Remove all inclusions of <linux/config.h>Dave Jones2006-10-04
| | | | | | | | | | | | kbuild explicitly includes this at build time. Signed-off-by: Dave Jones <davej@redhat.com>
* | Merge branch 'audit.b32' of ↵Linus Torvalds2006-10-04
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current * 'audit.b32' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current: [PATCH] message types updated [PATCH] name_count array overrun [PATCH] PPID filtering fix [PATCH] arch filter lists with < or > should not be accepted
| * | [PATCH] name_count array overrunSteve Grubb2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hi, This patch removes the rdev logging from the previous patch The below patch closes an unbounded use of name_count. This can lead to oopses in some new file systems. Signed-off-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] PPID filtering fixAlexander Viro2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Thu, Sep 28, 2006 at 04:03:06PM -0400, Eric Paris wrote: > After some looking I did not see a way to get into audit_log_exit > without having set the ppid. So I am dropping the set from there and > only doing it at the beginning. > > Please comment/ack/nak as soon as possible. Ehh... That's one hell of an overhead to be had ;-/ Let's be lazy. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] arch filter lists with < or > should not be acceptedEric Paris2006-10-04
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the kernel audit system represents arch's as numbers and will gladly accept comparisons between archs using >, <, >=, <= when the only thing that makes sense is = or !=. I'm told that the next revision of auditctl will do this checking but this will provide enforcement in the kernel even for old userspace. A simple command to show the issue would be to run auditctl -d entry,always -F arch>i686 -S chmod with this patch the kernel will reject this with -EINVAL Please comment/ack/nak as soon as possible. -Eric kernel/auditfilter.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | [PATCH] rcu: simplify/improve batch tuningOleg Nesterov2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kill a hard-to-calculate 'rsinterval' boot parameter and per-cpu rcu_data.last_rs_qlen. Instead, it adds adds a flag rcu_ctrlblk.signaled, which records the fact that one of CPUs has sent a resched IPI since the last rcu_start_batch(). Roughly speaking, we need two rcu_start_batch()s in order to move callbacks from ->nxtlist to ->donelist. This means that when ->qlen exceeds qhimark and continues to grow, we should send a resched IPI, and then do it again after we gone through a quiescent state. On the other hand, if it was already sent, we don't need to do it again when another CPU detects overflow of the queue. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: add sched torture type to rcutortureJosh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | Implement torture testing for the "sched" variant of RCU, which uses preempt_disable, preempt_enable, and synchronize_sched. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: add rcu_bh_sync torture type to rcutortureJosh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | | | Use the newly-generic synchronous deferred free function to implement torture testing for rcu_bh using synchronize_rcu_bh rather than the asynchronous call_rcu_bh. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: add rcu_sync torture type to rcutortureJosh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | Use the newly-generic synchronous deferred free function to implement torture testing for RCU using synchronize_rcu rather than the asynchronous call_rcu. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: refactor srcu_torture_deferred_free to work for any implementationJosh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | | | Make srcu_torture_deferred_free use cur_ops->sync() so it will work for any implementation. Move and rename it in preparation for use in the ops of other implementations. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] RCU: add fake writers to rcutortureJosh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rcutorture currently has one writer and an arbitrary number of readers. To better exercise some of the code paths in RCU implementations, add fake writer threads which call the synchronize function for the RCU variant in a loop, with a delay between calls to arrange for different numbers of writers running in parallel. [bunk@stusta.de: cleanup] Acked-by: Paul McKenney <paulmck@us.ibm.com> Cc: Dipkanar Sarma <dipankar@in.ibm.com> Signed-off-by: Josh Triplett <josh@freedesktop.org> 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] rcu: Fix sign bug making rcu_random always return the same sequenceJosh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rcu_random uses a counter rrs_count to occasionally mix data from get_random_bytes into the state of its pseudorandom generator. However, the rrs_counter gets declared as an unsigned long, and rcu_random checks for --rrs_count < 0, so this code will never mix any real random data into the state, and will thus always return the same sequence of random numbers. Also, change the return value of rcu_random from long to unsigned long, to avoid potential issues caused by the use of the % operator, which can return negative values for negative left operands. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: Avoid kthread_stop on invalid pointer if rcutorture reader ↵Josh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | startup fails rcu_torture_init kmallocs the array of reader threads, then creates each one with kthread_run, cleaning up with rcu_torture_cleanup if this fails. rcu_torture_cleanup calls kthread_stop on any non-NULL pointer in the array; however, any readers after the one that failed to start up will have invalid pointers, not null pointers. Avoid this by using kzalloc instead. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: Mention rcu_bh in description of rcutorture's torture_type ↵Josh Triplett2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | parameter The comment for rcutorture's torture_type parameter only lists the RCU variants rcu and srcu, but not rcu_bh; add rcu_bh to the list. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: Add MODULE_AUTHOR to rcutorture moduleJosh Triplett2006-10-04
| | | | | | | | | | | | | | Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] SRCU: report out-of-memory errorsAlan Stern2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the init_srcu_struct() routine has no way to report out-of-memory errors. This patch (as761) makes it return -ENOMEM when the per-cpu data allocation fails. The patch also makes srcu_init_notifier_head() report a BUG if a notifier head can't be initialized. Perhaps it should return -ENOMEM instead, but in the most likely cases where this might occur I don't think any recovery is possible. Notifier chains generally are not created dynamically. [akpm@osdl.org: avoid statement-with-side-effect in macro] Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] Add SRCU-based notifier chainsAlan Stern2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch (as751) adds a new type of notifier chain, based on the SRCU (Sleepable Read-Copy Update) primitives recently added to the kernel. An SRCU notifier chain is much like a blocking notifier chain, in that it must be called in process context and its callout routines are allowed to sleep. The difference is that the chain's links are protected by the SRCU mechanism rather than by an rw-semaphore, so calling the chain has extremely low overhead: no memory barriers and no cache-line bouncing. On the other hand, unregistering from the chain is expensive and the chain head requires special runtime initialization (plus cleanup if it is to be deallocated). SRCU notifiers are appropriate for notifiers that will be called very frequently and for which unregistration occurs very seldom. The proposed "task notifier" scheme qualifies, as may some of the network notifiers. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Acked-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] srcu-3: add SRCU operations to rcutorturePaul E. McKenney2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | Adds SRCU operations to rcutorture and updates rcutorture documentation. Also increases the stress imposed by the rcutorture test. [bunk@stusta.de: make needlessly global code static] Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Cc: Paul E. McKenney <paulmck@us.ibm.com> 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] srcu-3: RCU variant permitting read-side blockingPaul E. McKenney2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Updated patch adding a variant of RCU that permits sleeping in read-side critical sections. SRCU is as follows: o Each use of SRCU creates its own srcu_struct, and each srcu_struct has its own set of grace periods. This is critical, as it prevents one subsystem with a blocking reader from holding up SRCU grace periods for other subsystems. o The SRCU primitives (srcu_read_lock(), srcu_read_unlock(), and synchronize_srcu()) all take a pointer to a srcu_struct. o The SRCU primitives must be called from process context. o srcu_read_lock() returns an int that must be passed to the matching srcu_read_unlock(). Realtime RCU avoids the need for this by storing the state in the task struct, but SRCU needs to allow a given code path to pass through multiple SRCU domains -- storing state in the task struct would therefore require either arbitrary space in the task struct or arbitrary limits on SRCU nesting. So I kicked the state-storage problem up to the caller. Of course, it is not permitted to call synchronize_srcu() while in an SRCU read-side critical section. o There is no call_srcu(). It would not be hard to implement one, but it seems like too easy a way to OOM the system. (Hey, we have enough trouble with call_rcu(), which does -not- permit readers to sleep!!!) So, if you want it, please tell me why... [josht@us.ibm.com: sparse notation] Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Josh Triplett <josh@freedesktop.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] msi: simplify msi sanity checks by adding with generic irq codeEric W. Biederman2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently msi.c is doing sanity checks that make certain before an irq is destroyed it has no more users. By adding irq_has_action I can perform the test is a generic way, instead of relying on a msi specific data structure. By performing the core check in dynamic_irq_cleanup I ensure every user of dynamic irqs has a test present and we don't free resources that are in use. In msi.c this allows me to kill the attrib.state member of msi_desc and all of the assciated code to maintain it. To keep from freeing data structures when irq cleanup code is called to soon changing dyanamic_irq_cleanup is insufficient because there are msi specific data structures that are also not safe to free. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Tony Luck <tony.luck@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] genirq: irq: add a dynamic irq creation APIEric W. Biederman2006-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the msi support comes a new concept in irq handling, irqs that are created dynamically at run time. Currently the msi code allocates irqs backwards. First it allocates a platform dependent routing value for an interrupt the ``vector'' and then it figures out from the vector which irq you are on. This msi backwards allocator suffers from two basic problems. The allocator suffers because it is trying to do something that is architecture specific in a generic way making it brittle, inflexible, and tied to tightly to the architecture implementation. The alloctor also suffers from it's very backwards nature as it has tied things together that should have no dependencies. To solve the basic dynamic irq allocation problem two new architecture specific functions are added: create_irq and destroy_irq. create_irq takes no input and returns an unused irq number, that won't be reused until it is returned to the free poll with destroy_irq. The irq then can be used for any purpose although the only initial consumer is the msi code. destroy_irq takes an irq number allocated with create_irq and returns it to the free pool. Making this functionality per architecture increases the simplicity of the irq allocation code and increases it's flexibility. dynamic_irq_init() and dynamic_irq_cleanup() are added to automate the irq_desc initializtion that should happen for dynamic irqs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] genirq: irq: add moved_masked_irqEric W. Biederman2006-10-04
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