aboutsummaryrefslogtreecommitdiffstats
path: root/kernel
Commit message (Collapse)AuthorAge
* perf_counter: round-robin per-CPU counters tooIngo Molnar2009-05-04
| | | | | | | | | | | This used to be unstable when we had the rq->lock dependencies, but now that they are that of the past we can turn on percpu counter RR too. [ Impact: handle counter over-commit for per-CPU counters too ] LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf_counter: fix race in perf_output_*Peter Zijlstra2009-05-01
| | | | | | | | | | | | | | | | | When two (or more) contexts output to the same buffer, it is possible to observe half written output. Suppose we have CPU0 doing perf_counter_mmap(), CPU1 doing perf_counter_overflow(). If CPU1 does a wakeup and exposes head to user-space, then CPU2 can observe the data CPU0 is still writing. [ Impact: fix occasionally corrupted profiling records ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> LKML-Reference: <20090501102533.007821627@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'core/signal' into perfcounters/coreThomas Gleixner2009-04-30
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | This is necessary to avoid the conflict of syscall numbers. Conflicts: arch/x86/ia32/ia32entry.S arch/x86/include/asm/unistd_32.h arch/x86/include/asm/unistd_64.h Fixes up the borked syscall numbers of perfcounters versus preadv/pwritev as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * signals: implement sys_rt_tgsigqueueinfoThomas Gleixner2009-04-30
| | | | | | | | | | | | | | | | | | | | | | | | sys_kill has the per thread counterpart sys_tgkill. sigqueueinfo is missing a thread directed counterpart. Such an interface is important for migrating applications from other OSes which have the per thread delivery implemented. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Acked-by: Ulrich Drepper <drepper@redhat.com>
| * signals: split do_tkillThomas Gleixner2009-04-30
| | | | | | | | | | | | | | | | Split out the code from do_tkill to make it reusable by the follow up patch which implements sys_rt_tgsigqueueinfo Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Oleg Nesterov <oleg@redhat.com>
* | perf_counter: update copyright noticePaul Mackerras2009-04-30
| | | | | | | | | | | | | | | | | | | | | | | | This adds my name to the list of copyright holders on the core perf_counter.c, since I have contributed a significant amount of the code in there. Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> LKML-Reference: <18936.59200.888049.746658@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_counter: add/update copyrightsIngo Molnar2009-04-29
| | | | | | | | | | Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perfcounters: rename struct hw_perf_counter_ops into struct pmuRobert Richter2009-04-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch renames struct hw_perf_counter_ops into struct pmu. It introduces a structure to describe a cpu specific pmu (performance monitoring unit). It may contain ops and data. The new name of the structure fits better, is shorter, and thus better to handle. Where it was appropriate, names of function and variable have been changed too. [ Impact: cleanup ] Signed-off-by: Robert Richter <robert.richter@amd.com> Cc: Paul Mackerras <paulus@samba.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1241002046-8832-7-git-send-email-robert.richter@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'linus' into perfcounters/coreIngo Molnar2009-04-29
|\| | | | | | | | | | | | | Merge reason: This brach was on -rc1, refresh it to almost-rc4 to pick up the latest upstream fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * Merge branch 'for-linus' of ↵Linus Torvalds2009-04-27
| |\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: ptrace: ptrace_attach: fix the usage of ->cred_exec_mutex
| | * ptrace: ptrace_attach: fix the usage of ->cred_exec_mutexOleg Nesterov2009-04-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | ptrace_attach() needs task->cred_exec_mutex, not current->cred_exec_mutex. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
| * | Merge branch 'irq-fixes-for-linus' of ↵Linus Torvalds2009-04-26
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86/irq: mark NUMA_MIGRATE_IRQ_DESC broken x86, irq: Remove IRQ_DISABLED check in process context IRQ move
| | * | x86, irq: Remove IRQ_DISABLED check in process context IRQ movePallipadi, Venkatesh2009-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As discussed in the thread here: http://marc.info/?l=linux-kernel&m=123964468521142&w=2 Eric W. Biederman observed: > It looks like some additional bugs have slipped in since last I looked. > > set_irq_affinity does this: > ifdef CONFIG_GENERIC_PENDING_IRQ > if (desc->status & IRQ_MOVE_PCNTXT || desc->status & IRQ_DISABLED) { > cpumask_copy(desc->affinity, cpumask); > desc->chip->set_affinity(irq, cpumask); > } else { > desc->status |= IRQ_MOVE_PENDING; > cpumask_copy(desc->pending_mask, cpumask); > } > #else > > That IRQ_DISABLED case is a software state and as such it has nothing to > do with how safe it is to move an irq in process context. [...] > > The only reason we migrate MSIs in interrupt context today is that there > wasn't infrastructure for support migration both in interrupt context > and outside of it. Yes. The idea here was to force the MSI migration to happen in process context. One of the patches in the series did disable_irq(dev->irq); irq_set_affinity(dev->irq, cpumask_of(dev->cpu)); enable_irq(dev->irq); with the above patch adding irq/manage code check for interrupt disabled and moving the interrupt in process context. IIRC, there was no IRQ_MOVE_PCNTXT when we were developing this HPET code and we ended up having this ugly hack. IRQ_MOVE_PCNTXT was there when we eventually submitted the patch upstream. But, looks like I did a blind rebasing instead of using IRQ_MOVE_PCNTXT in hpet MSI code. Below patch fixes this. i.e., revert commit 932775a4ab622e3c99bd59f14cc and add PCNTXT to HPET MSI setup. Also removes copying of desc->affinity in generic code as set_affinity routines are doing it internally. Reported-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "Li Shaohua" <shaohua.li@intel.com> Cc: Gary Hade <garyhade@us.ibm.com> Cc: "lcm@us.ibm.com" <lcm@us.ibm.com> Cc: suresh.b.siddha@intel.com LKML-Reference: <20090413222058.GB8211@linux-os.sc.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds2009-04-26
| |\ \ \ | | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: locking: clarify kernel-taint warning message lockdep, x86: account for irqs enabled in paranoid_exit lockdep: more robust lockdep_map init sequence
| | * | locking: clarify kernel-taint warning messageIngo Molnar2009-04-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andi Kleen reported this message triggering on non-lockdep kernels: Disabling lockdep due to kernel taint Clarify the message to say 'lock debugging' - debug_locks_off() turns off all things lock debugging, not just lockdep. [ Impact: change kernel warning message text ] Reported-by: Andi Kleen <andi@firstfloor.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | lockdep: more robust lockdep_map init sequencePeter Zijlstra2009-04-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Steven Rostedt reported: > OK, I think I figured this bug out. This is a lockdep issue with respect > to tracepoints. > > The trace points in lockdep are called all the time. Outside the lockdep > logic. But if lockdep were to trigger an error / warning (which this run > did) we might be in trouble. For new locks, like the dentry->d_lock, that > are created, they will not get a name: > > void lockdep_init_map(struct lockdep_map *lock, const char *name, > struct lock_class_key *key, int subclass) > { > if (unlikely(!debug_locks)) > return; > > When a problem is found by lockdep, debug_locks becomes false. Thus we > stop allocating names for locks. This dentry->d_lock I had, now has no > name. Worse yet, I have CONFIG_DEBUG_VM set, that scrambles non > initialized memory. Thus, when the trace point was hit, it had junk for > the lock->name, and the machine crashed. Ah, nice catch. I think we should put at least the name in regardless. Ensure we at least initialize the trivial entries of the depmap so that they can be relied upon, even when lockdep itself decided to pack up and go home. [ Impact: fix lock tracing after lockdep warnings. ] Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1239954049.23397.4156.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | PM/Hibernate: Fix waiting for image device to appear on resumeRafael J. Wysocki2009-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c751085943362143f84346d274e0011419c84202 ("PM/Hibernate: Wait for SCSI devices scan to complete during resume") added a call to scsi_complete_async_scans() to software_resume(), so that it waited for the SCSI scanning to complete, but the call was added at a wrong place. Namely, it should have been added after wait_for_device_probe(), which is called only if the image partition hasn't been specified yet. Also, it's reasonable to check if the image partition is present and only wait for the device probing and SCSI scanning to complete if it is not the case. Additionally, since noresume is checked right at the beginning of software_resume() and the function returns immediately if it's set, it doesn't make sense to check it once again later. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | Delete slow-work timers properlyJonathan Corbet2009-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Slow-work appears to delete its timer as soon as the first user unregisters, even though other users could be active. At the same time, it never seems to delete slow_work_oom_timer. Arrange for both to happen in the shutdown path. Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | clocksource: add enable() and disable() callbacksMagnus Damm2009-04-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add enable() and disable() callbacks for clocksources. This allows us to put unused clocksources in power save mode. The functions clocksource_enable() and clocksource_disable() wrap the callbacks and are inserted in the timekeeping code to enable before use and disable after switching to a new clocksource. Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | clocksource: pass clocksource to read() callbackMagnus Damm2009-04-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pass clocksource pointer to the read() callback for clocksources. This allows us to share the callback between multiple instances. [hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods] [akpm@linux-foundation.org: cleanup] Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | No need for crossing to mountpoint in audit_tag_tree()Al Viro2009-04-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | is_under() will DTRT anyway. And yes, is_subdir() behaviour is intentional. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | PM/Suspend: Introduce two new platform callbacks to avoid breakageRafael J. Wysocki2009-04-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 900af0d973856d6feb6fc088c2d0d3fde57707d3 (PM: Change suspend code ordering) changed the ordering of suspend code in such a way that the platform .prepare() callback is now executed after the device drivers' late suspend callbacks have run. Unfortunately, this turns out to break ARM platforms that need to talk via I2C to power control devices during the .prepare() callback. For this reason introduce two new platform suspend callbacks, .prepare_late() and .wake(), that will be called just prior to disabling non-boot CPUs and right after bringing them back on line, respectively, and use them instead of .prepare() and .finish() for ACPI suspend. Make the PM core execute the .prepare() and .finish() platform suspend callbacks where they were executed previously (that is, right after calling the regular suspend methods provided by device drivers and right before executing their regular resume methods, respectively). It is not necessary to make analogous changes to the hibernation code and data structures at the moment, because they are only used by ACPI platforms. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reported-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Len Brown <len.brown@intel.com>
| * | | Remove 'recurse into child resources' logic from 'reserve_region_with_split()'Linus Torvalds2009-04-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This function is not actually used right now, since the original use case for it was done with insert_resource_expand_to_fit() instead. However, we now have another usage case that wants to basically do a "reserve IO resource, splitting around existing resources", however that one doesn't actually want the "recurse into the conflicting resource" logic at all. And since recursing into the conflicting resource was the most complex part, and isn't wanted, just remove it. Maybe we'll some day want both versions, but we can just resurrect the logic then. Tested-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds2009-04-16
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Fix branch tracer header tracing: Fix power tracer header
| | * | | tracing: Fix branch tracer headerZhaolei2009-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before patch: # tracer: branch # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | <...>-2981 [000] 24008.872738: [ ok ] trace_irq_handler_exit:irq_event_types.h:41 <...>-2981 [000] 24008.872742: [ ok ] note_interrupt:spurious.c:229 ... After patch: # tracer: branch # # TASK-PID CPU# TIMESTAMP CORRECT FUNC:FILE:LINE # | | | | | | <...>-2985 [000] 26329.142970: [ ok ] slab_free:slub.c:1776 <...>-2985 [000] 26329.142972: [ ok ] trace_kmem_cache_free:kmem_event_types.h:191 ... Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <49E2F19A.3040006@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | tracing: Fix power tracer headerZhaolei2009-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before patch: # tracer: power # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | [ 676.875865889] CSTATE: Going to C1 on cpu 0 for 0.005911463 [ 676.882938805] CSTATE: Going to C1 on cpu 0 for 0.104796532 ... After patch: # tracer: power # # TIMESTAMP STATE EVENT # | | | [ 676.875865889] CSTATE: Going to C1 on cpu 0 for 0.005911463 [ 676.882938805] CSTATE: Going to C1 on cpu 0 for 0.104796532 ... v2: Use seq_puts instead of seq_printf Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <49E2E889.5000903@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds2009-04-16
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: Avoid printing sched_group::__cpu_power for default case tracing, sched: mark get_parent_ip() notrace
| | * | | | sched: Avoid printing sched_group::__cpu_power for default caseGautham R Shenoy2009-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 46e0bb9c12f4 ("sched: Print sched_group::__cpu_power in sched_domain_debug") produces a messy dmesg output while attempting to print the sched_group::__cpu_power for each group in the sched_domain hierarchy. Fix this by avoid printing the __cpu_power for default cases. (i.e, __cpu_power == SCHED_LOAD_SCALE). [ Impact: reduce syslog clutter ] Reported-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Gautham R Shenoy <ego@in.ibm.com> Fixed-by: Tony Luck <tony.luck@intel.com> Cc: a.p.zijlstra@chello.nl LKML-Reference: <20090414033936.GA534@in.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | tracing, sched: mark get_parent_ip() notraceLai Jiangshan2009-04-13
| | | |_|/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: remove overly redundant tracing entries When tracer is "function" or "function_graph", way too much "get_parent_ip" entries are recorded in ring_buffer. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49D458B1.5000703@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds2009-04-16
| |\ \ \ \ | | | |_|/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: kernel/softirq.c: fix sparse warning rcu: Make hierarchical RCU less IPI-happy
| | * | | kernel/softirq.c: fix sparse warningH Hartley Sweeten2009-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix sparse warning in kernel/softirq.c. warning: do-while statement is not a compound statement Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> LKML-Reference: <BD79186B4FD85F4B8E60E381CAEE1909015F9033@mi8nycmail19.Mi8.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | rcu: Make hierarchical RCU less IPI-happyPaul E. McKenney2009-04-14
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a hierarchical-RCU performance bug located by Anton Blanchard. The problem stems from a misguided attempt to provide a work-around for jiffies-counter failure. This work-around uses a per-CPU n_rcu_pending counter, which is incremented on each call to rcu_pending(), which in turn is called from each scheduling-clock interrupt. Each CPU then treats this counter as a surrogate for the jiffies counter, so that if the jiffies counter fails to advance, the per-CPU n_rcu_pending counter will cause RCU to invoke force_quiescent_state(), which in turn will (among other things) send resched IPIs to CPUs that have thus far failed to pass through an RCU quiescent state. Unfortunately, each CPU resets only its own counter after sending a batch of IPIs. This means that the other CPUs will also (needlessly) send -another- round of IPIs, for a full N-squared set of IPIs in the worst case every three scheduler-clock ticks until the grace period finally ends. It is not reasonable for a given CPU to reset each and every n_rcu_pending for all the other CPUs, so this patch instead simply disables the jiffies-counter "training wheels", thus eliminating the excessive IPIs. Note that the jiffies-counter IPIs do not have this problem due to the fact that the jiffies counter is global, so that the CPU sending the IPIs can easily reset things, thus preventing the other CPUs from sending redundant IPIs. Note also that the n_rcu_pending counter remains, as it will continue to be used for tracing. It may also see use to update the jiffies counter, should an appropriate kick-the-jiffies-counter API appear. Located-by: Anton Blanchard <anton@au1.ibm.com> Tested-by: Anton Blanchard <anton@au1.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: anton@samba.org Cc: akpm@linux-foundation.org Cc: dipankar@in.ibm.com Cc: manfred@colorfullife.com Cc: cl@linux-foundation.org Cc: josht@linux.vnet.ibm.com Cc: schamp@sgi.com Cc: niv@us.ibm.com Cc: dvhltc@us.ibm.com Cc: ego@in.ibm.com Cc: laijs@cn.fujitsu.com Cc: rostedt@goodmis.org Cc: peterz@infradead.org Cc: penberg@cs.helsinki.fi Cc: andi@firstfloor.org Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> LKML-Reference: <12396834793575-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | RCU: Don't try and predeclare inline funcs as it upsets some versions of gccDavid Howells2009-04-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't try and predeclare inline funcs like this: static inline void wait_migrated_callbacks(void) ... static void _rcu_barrier(enum rcu_barrier type) { ... wait_migrated_callbacks(); } ... static inline void wait_migrated_callbacks(void) { wait_event(rcu_migrate_wq, !atomic_read(&rcu_migrate_type_count)); } as it upsets some versions of gcc under some circumstances: kernel/rcupdate.c: In function `_rcu_barrier': kernel/rcupdate.c:125: sorry, unimplemented: inlining failed in call to 'wait_migrated_callbacks': function body not available kernel/rcupdate.c:152: sorry, unimplemented: called from here This can be dealt with by simply putting the static variables (rcu_migrate_*) at the top, and moving the implementation of the function up so that it replaces its forward declaration. Signed-off-by: David Howells <dhowells@redhat.com> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | swap: Remove code handling bio_alloc failure with __GFP_WAITNikanth Karthikesan2009-04-15
| |/ / | | | | | | | | | | | | | | | | | | Remove code handling bio_alloc failure with __GFP_WAIT. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | kernel/sys.c: clean up sys_shutdown exit pathAndi Kleen2009-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup, fix Clean up sys_shutdown() exit path. Factor out common code. Return correct error code instead of always 0 on failure. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | ptrace: fix exit_ptrace() vs ptrace_traceme() raceOleg Nesterov2009-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pointed out by Roland. The bug was recently introduced by me in "forget_original_parent: split out the un-ptrace part", commit 39c626ae47c469abdfd30c6e42eff884931380d6. Since that patch we have a window after exit_ptrace() drops tasklist and before forget_original_parent() takes it again. In this window the child can do ptrace(PTRACE_TRACEME) and nobody can untrace this child after that. Change ptrace_traceme() to not attach to the exiting ->real_parent. We don't report the error in this case, we pretend we attach right before ->real_parent calls exit_ptrace() which should untrace us anyway. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | mm: move the scan_unevictable_pages sysctl to the vm tablePeter Zijlstra2009-04-13
| |/ | | | | | | | | | | | | | | | | | | | | vm knobs should go in the vm table. Probably too late for randomize_va_space though. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * PM/Hibernate: Wait for SCSI devices scan to complete during resumeRafael J. Wysocki2009-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a race between resume from hibernation and the asynchronous scanning of SCSI devices and to prevent it from happening we need to call scsi_complete_async_scans() during resume from hibernation. In addition, if the resume from hibernation is userland-driven, it's better to wait for all device probes in the kernel to complete before attempting to open the resume device. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds2009-04-13
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing/filters: return proper error code when writing filter file tracing/filters: allow user input integer to be oct or hex tracing/filters: fix NULL pointer dereference tracing/filters: NIL-terminate user input filter ftrace: Output REC->var instead of __entry->var for trace format Make __stringify support variable argument macros too tracing: fix document references tracing: fix splice return too large tracing: update file->f_pos when splice(2) it tracing: allocate page when needed tracing: disable seeking for trace_pipe_raw
| | * tracing/filters: return proper error code when writing filter fileLi Zefan2009-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - propagate return value of filter_add_pred() to the user - return -ENOSPC but not -ENOMEM or -EINVAL when the filter array is full Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Tom Zanussi <tzanussi@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49E04CF0.3010105@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing/filters: allow user input integer to be oct or hexLi Zefan2009-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before patch: # echo 'parent_pid == 0x10' > events/sched/sched_process_fork/filter # cat sched/sched_process_fork/filter parent_pid == 0 After patch: # cat sched/sched_process_fork/filter parent_pid == 16 Also check the input more strictly. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Tom Zanussi <tzanussi@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49E04C53.4010600@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing/filters: fix NULL pointer dereferenceLi Zefan2009-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Try this, and you'll see NULL pointer dereference bug: # echo -n 'parent_comm ==' > sched/sched_process_fork/filter Because we passed NULL ptr to simple_strtoull(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Tom Zanussi <tzanussi@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49E04C43.1050504@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing/filters: NIL-terminate user input filterLi Zefan2009-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure messages from user space are NIL-terminated strings, otherwise we could dump random memory while reading filter file. Try this: # echo 'parent_comm ==' > events/sched/sched_process_fork/filter # cat events/sched/sched_process_fork/filter parent_comm == � Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Tom Zanussi <tzanussi@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49E04C32.6060508@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * ftrace: Output REC->var instead of __entry->var for trace formatZhaolei2009-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | print fmt: "irq=%d return=%s", __entry->irq, __entry->ret ? \"handled\" : \"unhandled\" "__entry" should be convert to "REC" by __stringify() macro. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49DC679D.2090901@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing: fix document referencesLi Zefan2009-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When moving documents to Documentation/trace/, I forgot to grep Kconfig to find out those references. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Pekka Paalanen <pq@iki.fi> Cc: eduard.munteanu@linux360.ro LKML-Reference: <49DE97EF.7080208@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing: fix splice return too largeLai Jiangshan2009-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I got these from strace: splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 16384 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192 splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192 I wanted to splice_read 4096 bytes, but it returns 8192 or larger. It is because the return value of tracing_buffers_splice_read() does not include "zero out any left over data" bytes. But tracing_buffers_read() includes these bytes, we make them consistent. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49D46674.9030804@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing: update file->f_pos when splice(2) itLai Jiangshan2009-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: Cleanup These two lines: if (unlikely(*ppos)) return -ESPIPE; in tracing_buffers_splice_read() are not needed, VFS layer has disabled seek(2). We remove these two lines, and then we can update file->f_pos. And tracing_buffers_read() updates file->f_pos, this fix make tracing_buffers_splice_read() updates file->f_pos too. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49D46670.4010503@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing: allocate page when neededLai Jiangshan2009-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: Cleanup Sometimes, we open trace_pipe_raw, but we don't read(2) it, we just splice(2) it, thus, the page is not used. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49D4666B.4010608@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * tracing: disable seeking for trace_pipe_rawLai Jiangshan2009-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: disable pread() We set tracing_buffers_fops.llseek to no_llseek, but we can still perform pread() to read this file. That is not expected. This fix uses nonseekable_open() to disable it. tracing_buffers_fops.llseek is still set to no_llseek, it mark this file is a "non-seekable device" and is used by sys_splice(). See also do_splice() or manual of splice(2): ERRORS EINVAL Target file system doesn't support splicing; neither of the descriptors refers to a pipe; or offset given for non-seekable device. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49D46668.8030806@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds2009-04-13
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: lockdep: continue lock debugging despite some taints lockdep: warn about lockdep disabling after kernel taint