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* perf: Honour event state for aux stream dataPeter Zijlstra2010-01-211-0/+9
| | | | | | | | | | | | | Anton reported that perf record kept receiving events even after calling ioctl(PERF_EVENT_IOC_DISABLE). It turns out that FORK,COMM and MMAP events didn't respect the disabled state and kept flowing in. Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: Anton Blanchard <anton@samba.org> LKML-Reference: <1263459187.4244.265.camel@laptop> CC: stable@kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'perf-fixes-for-linus-2' of ↵Linus Torvalds2009-12-311-3/+2
|\ | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf: Fix NULL deref in inheritance code perf: Pass appropriate frame pointer to dump_trace()
| * perf: Fix NULL deref in inheritance codePeter Zijlstra2009-12-311-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Liming found a NULL deref when a task has a perf context but no counters when it forks. This can occur in two cases, a race during construction where the fork hits after installing the context but before the first counter gets inserted, or more reproducably, a fork after the last counter is closed (which leaves the context around). Reported-by: Wang Liming <liming.wang@windriver.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> CC: <stable@kernel.org> LKML-Reference: <1262185684.7135.222.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | anonfd: Allow making anon files read-onlyRoland Dreier2009-12-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | It seems a couple places such as arch/ia64/kernel/perfmon.c and drivers/infiniband/core/uverbs_main.c could use anon_inode_getfile() instead of a private pseudo-fs + alloc_file(), if only there were a way to get a read-only file. So provide this by having anon_inode_getfile() create a read-only file if we pass O_RDONLY in flags. Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds2009-12-191-14/+18
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf session: Make events_stats u64 to avoid overflow on 32-bit arches hw-breakpoints: Fix hardware breakpoints -> perf events dependency perf events: Dont report side-band events on each cpu for per-task-per-cpu events perf events, x86/stacktrace: Fix performance/softlockup by providing a special frame pointer-only stack walker perf events, x86/stacktrace: Make stack walking optional perf events: Remove unused perf_counter.h header file perf probe: Check new event name kprobe-tracer: Check new event/group name perf probe: Check whether debugfs path is correct perf probe: Fix libdwarf include path for Debian
| * perf events: Dont report side-band events on each cpu for per-task-per-cpu ↵Peter Zijlstra2009-12-171-14/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | events Acme noticed that his FORK/MMAP numbers were inflated by about the same factor as his cpu-count. This led to the discovery of a few more sites that need to respect the event->cpu filter. Reported-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091217121830.215333434@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | cpumask: use cpu_online in kernel/perf_event.cRusty Russell2009-12-171-1/+1
|/ | | | | | | | Also, we want to check against nr_cpu_ids, not num_possible_cpus(). The latter works, but the correct bounds check is < nr_cpu_ids. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> To: Thomas Gleixner <tglx@linutronix.de>
* Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds2009-12-161-6/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (52 commits) perf record: Use per-task-per-cpu events for inherited events perf record: Properly synchronize child creation perf events: Allow per-task-per-cpu counters perf diff: Percent calcs should use double values perf diff: Change the default sort order to "dso,symbol" perf diff: Use perf_session__fprintf_hists just like 'perf record' perf report: Fix cut'n'paste error recently introduced perf session: Move perf report specific hits out of perf_session__fprintf_hists perf tools: Move hist entries printing routines from perf report perf report: Generalize perf_session__fprintf_hists() perf symbols: Move symbol filtering to event__preprocess_sample() perf symbols: Adopt the strlists for dso, comm perf symbols: Make symbol_conf global perf probe: Fix to show which probe point is not found perf probe: Check symbols in symtab/kallsyms perf probe: Check build-id of vmlinux perf probe: Reject second attempt of adding same-name event perf probe: Support event name for --add option perf probe: Add glob matching support on --del perf probe: Use strlist__for_each macros in probe-event.c ...
| * perf events: Allow per-task-per-cpu countersPeter Zijlstra2009-12-161-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to allow for per-task-per-cpu counters, useful for scalability when profiling task hierarchies, we allow installing events with event->cpu != -1 in task contexts. __perf_event_sched_in() already skips events where ->cpu mis-matches the current cpu, fix up __perf_install_in_context() and __perf_event_enable() to also respect this filter. This does lead to vary hard to interpret enabled/running times for such counters, but I don't see a simple solution for that. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: fweisbec@gmail.com Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091216165904.831451147@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf_events: Fix perf_event_attr layoutPeter Zijlstra2009-12-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The miss-alignment of bp_addr created a 32bit hole, causing different structure packings on 32 and 64 bit machines. Fix that by moving __reserve_2 into that hole. Further, remove the useless struct and redundant __bp_reserve muck. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <1260902591.8023.781.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf_event: Fix incorrect range check on cpu numberPaul Mackerras2009-12-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is quite legitimate for CPUs to be numbered sparsely, meaning that it possible for an online CPU to have a number which is greater than the total count of possible CPUs. Currently find_get_context() has a sanity check on the cpu number where it checks it against num_possible_cpus(). This test can fail for a legitimate cpu number if the cpu_possible_mask is sparsely populated. This fixes the problem by checking the CPU number against nr_cpumask_bits instead, since that is the appropriate check to ensure that the cpu number is same to pass to cpu_isset() subsequently. Reported-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org> Tested-by: Michael Neuling <mikey@neuling.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: <stable@kernel.org> LKML-Reference: <20091215084032.GA18661@brick.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_event: Convert to raw_spinlockThomas Gleixner2009-12-141-53/+53
| | | | | | | | | | | | | | | | | | Convert locks which cannot be sleeping locks in preempt-rt to raw_spinlocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds2009-12-111-37/+38
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (57 commits) x86, perf events: Check if we have APIC enabled perf_event: Fix variable initialization in other codepaths perf kmem: Fix unused argument build warning perf symbols: perf_header__read_build_ids() offset'n'size should be u64 perf symbols: dsos__read_build_ids() should read both user and kernel buildids perf tools: Align long options which have no short forms perf kmem: Show usage if no option is specified sched: Mark sched_clock() as notrace perf sched: Add max delay time snapshot perf tools: Correct size given to memset perf_event: Fix perf_swevent_hrtimer() variable initialization perf sched: Fix for getting task's execution time tracing/kprobes: Fix field creation's bad error handling perf_event: Cleanup for cpu_clock_perf_event_update() perf_event: Allocate children's perf_event_ctxp at the right time perf_event: Clean up __perf_event_init_context() hw-breakpoints: Modify breakpoints without unregistering them perf probe: Update perf-probe document perf probe: Support --del option trace-kprobe: Support delete probe syntax ...
| * perf_event: Fix variable initialization in other codepathsXiao Guangrong2009-12-101-0/+1
| | | | | | | | | | | | | | | | | | Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B20BAA6.7010609@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf_event: Fix perf_swevent_hrtimer() variable initializationXiao Guangrong2009-12-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fix: [<c0477471>] ? printk+0x1d/0x24 [<c01c98f9>] ? perf_prepare_sample+0x269/0x280 [<c0149231>] warn_slowpath_common+0x71/0xd0 [<c01c98f9>] ? perf_prepare_sample+0x269/0x280 [<c01492aa>] warn_slowpath_null+0x1a/0x20 [<c01c98f9>] perf_prepare_sample+0x269/0x280 [<c016e9f3>] ? cpu_clock+0x53/0x90 [<c01cc368>] __perf_event_overflow+0x2a8/0x300 [<c01ccc3b>] perf_event_overflow+0x1b/0x30 [<c01ccccf>] perf_swevent_hrtimer+0x7f/0x120 This is because 'data.raw' variable not initialize. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B208E93.1010801@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf_event: Cleanup for cpu_clock_perf_event_update()Xiao Guangrong2009-12-091-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | Using atomic64_xchg() instead of atomic64_read() and atomic64_set(). Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B1F19DC.90204@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf_event: Allocate children's perf_event_ctxp at the right timeXiao Guangrong2009-12-091-15/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In current code, children task will allocate memory for 'child->perf_event_ctxp' if the parent is counted, we can do it only if the parent allowed children inherit it. It can save memory and reduce overhead. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B1F19A8.5040805@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf_event: Clean up __perf_event_init_context()Xiao Guangrong2009-12-091-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean up the code a bit: - define 'perf_cpu_context' variable with 'static' - use kzalloc() instead of kmalloc() and memset() Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B1F194D.7080306@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * hw-breakpoints: Modify breakpoints without unregistering themFrederic Weisbecker2009-12-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when ptrace needs to modify a breakpoint, like disabling it, changing its address, type or len, it calls modify_user_hw_breakpoint(). This latter will perform the heavy and racy task of unregistering the old breakpoint and registering a new one. This is racy as someone else might steal the reserved breakpoint slot under us, which is undesired as the breakpoint is only supposed to be modified, sometimes in the middle of a debugging workflow. We don't want our slot to be stolen in the middle. So instead of unregistering/registering the breakpoint, just disable it while we modify its breakpoint fields and re-enable it after if necessary. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prasad <prasad@linux.vnet.ibm.com> LKML-Reference: <1260347148-5519-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * hw-breakpoints: Use overflow handler instead of the event callbackFrederic Weisbecker2009-12-061-15/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct perf_event::event callback was called when a breakpoint triggers. But this is a rather opaque callback, pretty tied-only to the breakpoint API and not really integrated into perf as it triggers even when we don't overflow. We prefer to use overflow_handler() as it fits into the perf events rules, being called only when we overflow. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
* | Merge branch 'for-next' into for-linusJiri Kosina2009-12-071-2/+2
|\ \ | |/ |/| | | | | | | Conflicts: kernel/irq/chip.c
| * tree-wide: fix assorted typos all over the placeAndré Goddard Rosa2009-12-041-2/+2
| | | | | | | | | | | | | | | | | | | | That is "success", "unknown", "through", "performance", "[re|un]mapping" , "access", "default", "reasonable", "[con]currently", "temperature" , "channel", "[un]used", "application", "example","hierarchy", "therefore" , "[over|under]flow", "contiguous", "threshold", "enough" and others. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | perf: Don't free perf_mmap_data until work has been doneKristian Høgsberg2009-12-021-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the CONFIG_PERF_USE_VMALLOC case, perf_mmap_data_free() only schedules the cleanup of the perf_mmap_data struct. In that case we have to wait until the work has been done before we free data. Signed-off-by: Kristian Høgsberg <krh@bitplanet.net> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: <stable@kernel.org> LKML-Reference: <1259697901-1747-1-git-send-email-krh@bitplanet.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_event: Initialize data.period in perf_swevent_hrtimer()Xiao Guangrong2009-12-011-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In current code in perf_swevent_hrtimer(), data.period is not initialized, The result is obvious wrong: # ./perf record -f -e cpu-clock make # ./perf report # Samples: 1740 # # Overhead Command ...... # ........ ........ .......................................... # 1025422183050275328.00% sh libc-2.9.90.so ... 1025422183050275328.00% perl libperl.so ... 1025422168240043264.00% perl [kernel] ... 1025422030011210752.00% perl [kernel] ... Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: <stable@kernel.org> LKML-Reference: <4B14E220.2050107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Fix read() bogus counts when in error stateStephane Eranian2009-11-261-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a pinned group cannot be scheduled it goes into error state. Normally a group cannot go out of error state without being explicitly re-enabled or disabled. There was a bug in per-thread mode, whereby upon termination of the thread, the group would transition from error to off leading to bogus counts and timing information returned by read(). Fix it by clearing the error state. Signed-off-by: Stephane Eranian <eranian@google.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: perfmon2-devel@lists.sourceforge.net LKML-Reference: <4b0eb9ce.0508d00a.573b.ffffeab6@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | hw-breakpoints: Fix unused function in off-caseFrederic Weisbecker2009-11-261-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | bp_perf_event_destroy() is unused in its off-case version, let's remove it to fix the following warning reported by Stephen Rothwell in linux-next: kernel/perf_event.c:4306: warning: 'bp_perf_event_destroy' defined but not used Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1259180453-5813-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | hw-breakpoints: Improve in-kernel event creation error granularityFrederic Weisbecker2009-11-261-9/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In fail case, perf_event_create_kernel_counter() returns NULL instead of an error, which doesn't help us to inform the user about the origin of the problem from the outer most callers. Often we can just return -EINVAL, which doesn't help anyone when it's eventually about a memory allocation failure. Then, this patch makes perf_event_create_kernel_counter() always return a detailed error code. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Prasad <prasad@linux.vnet.ibm.com> LKML-Reference: <1259210142-5714-2-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Fix bad software/trace event recursion countingFrederic Weisbecker2009-11-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 4ed7c92d68a5387ba5f7030dc76eab03558e27f5 (perf_events: Undo some recursion damage) has introduced a bad reference counting of the recursion context. putting the context behaves like getting it, dropping every software/trace events after the first one in a context. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1259091502-5171-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Fix bogus copy_to_user() in perf_event_read_group()Stephane Eranian2009-11-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | When using an event group, the value and id for non leaders events were wrong due to invalid offset into the outgoing buffer. Signed-off-by: Stephane Eranian <eranian@google.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: paulus@samba.org Cc: perfmon2-devel@lists.sourceforge.net LKML-Reference: <4b0b71e1.0508d00a.075e.ffff84a3@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Add kernel side syscall events support for breakpointsFrederic Weisbecker2009-11-231-9/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the remaining necessary bits to support breakpoints created through perf syscall. We don't use the software counter interface as: - We don't need to check against recursion, this is already done in hardware breakpoints arch level. - We already know the perf event we are dealing with when the event is to be committed. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Prasad <prasad@linux.vnet.ibm.com> LKML-Reference: <1258987355-8751-3-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Restore sanity to scaling landPeter Zijlstra2009-11-231-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is quite possible to call update_event_times() on a context that isn't actually running and thereby confuse the thing. perf stat was reporting !100% scale values for software counters (2e2af50b perf_events: Disable events when we detach them, solved the worst of that, but there was still some left). The thing that happens is that because we are not self-reaping (we have a caring parent) there is a time between the last schedule (out) and having do_exit() called which will detach the events. This period would be accounted as enabled,!running because the event->state==INACTIVE, even though !event->ctx->is_active. Similar issues could have been observed by calling read() on a event while the attached task was not scheduled in. Solve this by teaching update_event_times() about ctx->is_active. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1258984836.4531.480.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Undo some recursion damagePeter Zijlstra2009-11-231-39/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Make perf_swevent_get_recursion_context return a context number and disable preemption. This could be used to remove the IRQ disable from the trace bit and index the per-cpu buffer with. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091123103819.993226816@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Fix __perf_event_exit_task() vs. update_event_times() lockingPeter Zijlstra2009-11-231-39/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | Move the update_event_times() call in __perf_event_exit_task() into list_del_event() because that holds the proper lock (ctx->lock) and seems a more natural place to do the last time update. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091123103819.842455480@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Update the context time on exitPeter Zijlstra2009-11-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It appeared we did call update_event_times() on exit, but we failed to update the context time, which renders the former moot. Locking is a bit iffy, we call update_event_times under ctx->mutex instead of ctx->lock - the next patch fixes this. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091123103819.764207355@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Disable events when we detach themPeter Zijlstra2009-11-231-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | If we leave the event in STATE_INACTIVE, any read of the event after the detach will increase the running count but not the enabled count and cause funny scaling artefacts. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091123103819.689055515@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Fix style nitsPeter Zijlstra2009-11-231-4/+3
| | | | | | | | | | | | | | | | Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091123103819.613427378@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Undo copy/paste damagePeter Zijlstra2009-11-231-22/+9
| | | | | | | | | | | | | | | | | | | | | | | | We had two almost identical functions, avoid the duplication. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <20091123103819.537537928@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Optimize the swcounter hotpathIngo Molnar2009-11-231-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The structure init creates a bit memcpy, which shows up big time in perf annotate output: : ffffffff810a859d <__perf_sw_event>: 1.68 : ffffffff810a859d: 55 push %rbp 1.69 : ffffffff810a859e: 41 89 fa mov %edi,%r10d 0.01 : ffffffff810a85a1: 49 89 c9 mov %rcx,%r9 0.00 : ffffffff810a85a4: 31 c0 xor %eax,%eax 1.71 : ffffffff810a85a6: b9 16 00 00 00 mov $0x16,%ecx 0.00 : ffffffff810a85ab: 48 89 e5 mov %rsp,%rbp 0.00 : ffffffff810a85ae: 48 83 ec 60 sub $0x60,%rsp 1.52 : ffffffff810a85b2: 48 8d 7d a0 lea -0x60(%rbp),%rdi 85.20 : ffffffff810a85b6: f3 ab rep stos %eax,%es:(%rdi) None of the callees depends on the structure being pre-initialized, so only initialize ->addr. This gets rid of the memcpy overhead. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Fix modular buildIngo Molnar2009-11-221-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix: ERROR: "perf_swevent_put_recursion_context" [fs/ext4/ext4.ko] undefined! ERROR: "perf_swevent_get_recursion_context" [fs/ext4/ext4.ko] undefined! Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jason Baron <jbaron@redhat.com> LKML-Reference: <1258864015-10579-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_event: Remove redundant zero fillMárton Németh2009-11-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The buffer is first zeroed out by memset(). Then strncpy() is used to fill the content. The strncpy() function also pads the string till the end of the specified length, which is redundant. The strncpy() does not ensures that the string will be properly closed with 0. Use strlcpy() instead. The semantic match that finds this kind of pattern is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression buffer; expression size; expression str; @@ memset(buffer, 0, size); ... - strncpy( + strlcpy( buffer, str, sizeof(buffer) ); @@ expression buffer; expression size; expression str; @@ memset(&buffer, 0, size); ... - strncpy( + strlcpy( &buffer, str, sizeof(buffer)); @@ expression buffer; identifier field; expression size; expression str; @@ memset(buffer, 0, size); ... - strncpy( + strlcpy( buffer->field, str, sizeof(buffer->field) ); @@ expression buffer; identifier field; expression size; expression str; @@ memset(&buffer, 0, size); ... - strncpy( + strlcpy( buffer.field, str, sizeof(buffer.field)); // </smpl> On strncpy() vs strlcpy() see http://www.gratisoft.us/todd/papers/strlcpy.html . Signed-off-by: Márton Németh <nm127@freemail.hu> Cc: Julia Lawall <julia@diku.dk> Cc: cocci@diku.dk Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <4B086547.5040100@freemail.hu> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | tracing: Use the perf recursion protection from trace eventFrederic Weisbecker2009-11-221-23/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we commit a trace to perf, we first check if we are recursing in the same buffer so that we don't mess-up the buffer with a recursing trace. But later on, we do the same check from perf to avoid commit recursion. The recursion check is desired early before we touch the buffer but we want to do this check only once. Then export the recursion protection from perf and use it from the trace events before submitting a trace. v2: Put appropriate Reported-by tag Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jason Baron <jbaron@redhat.com> LKML-Reference: <1258864015-10579-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf_events: Fix default watermark calculationStephane Eranian2009-11-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the default watermark value for the sampling buffer. With the existing calculation (watermark = max(PAGE_SIZE, max_size / 2)), no notification was ever received when the buffer was exactly 1 page. This was because you would never cross the threshold (there is no partial samples). In certain configuration, there was no possibilty detecting the problem because there was not enough space left to store the LOST record.In fact, there may be a more generic problem here. The kernel should ensure that there is alaways enough space to store one LOST record. This patch sets the default watermark to half the buffer size. With such limit, we are guaranteed to get a notification even with a single page buffer assuming no sample is bigger than a page. Signed-off-by: Stephane Eranian <eranian@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212509.344964101@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1256302576-6169-1-git-send-email-eranian@gmail.com>
* | perf: Fix locking for PERF_FORMAT_GROUPPeter Zijlstra2009-11-211-7/+13
| | | | | | | | | | | | | | | | | | | | We should hold event->child_mutex when iterating the inherited counters, we should hold ctx->mutex when iterating siblings. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212509.251030114@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Fix event scaling for inherited countersPeter Zijlstra2009-11-211-22/+26
| | | | | | | | | | | | | | | | | | | | Properly account the full hierarchy of counters for both the count (we already did so) and the scale times (new). Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212509.153379276@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Fix time lockingPeter Zijlstra2009-11-211-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Most sites updating ctx->time and event times do so under ctx->lock, make sure they all do. This was made possible by removing the __perf_event_read() call from __perf_event_sync_stat(), which already had this lock taken. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212509.102316434@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Simplify __perf_event_readPeter Zijlstra2009-11-211-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | cpuctx is always active, task context is always active for current the previous condition verifies that if its a task context its for current, hence we can assume ctx->is_active. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212509.000272254@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Simplify __perf_event_sync_statPeter Zijlstra2009-11-211-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Removes constraints from __perf_event_read() by leaving it with a single callsite; this callsite had ctx->lock held, the other one does not. Removes some superfluous code from __perf_event_sync_stat(). Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212508.918544317@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Optimize __perf_event_read()Peter Zijlstra2009-11-211-3/+0
| | | | | | | | | | | | | | | | | | | | Both callers actually have IRQs disabled, no need doing so again. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212508.863685796@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Optimize perf_event_task_sched_outPeter Zijlstra2009-11-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove an update_context_time() call from the perf_event_task_sched_out() path and into the branch its needed. The call was both superfluous, because __perf_event_sched_out() already does it, and wrong, because it was done without holding ctx->lock. Place it in perf_event_sync_stat(), which is the only place it is needed and which does already hold ctx->lock. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212508.779516394@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | perf: Fix PERF_FORMAT_GROUP scale infoPeter Zijlstra2009-11-211-31/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Corey reported, the total_enabled and total_running times could occasionally be 0, even though there were events counted. It turns out this is because we record the times before reading the counter while the latter updates the times. This patch corrects that. While looking at this code I found that there is a lot of locking iffyness around, the following patches correct most of that. Reported-by: Corey Ashford <cjashfor@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091120212508.685559857@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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