kernel/include/linux/perf_event.h, branch linux-3.5.y

perf/x86/ibs: Check syscall attribute flags

2012-10-02T17:39:25Z

commit bad9ac2d7f878a31cf1ae8c1ee3768077d222bcb upstream. Current implementation simply ignores attribute flags. Thus, there is no notification to userland of unsupported features. Check syscall's attribute flags to let userland know if a feature is supported by the kernel. This is also needed to distinguish between future kernels what might support a feature. Signed-off-by: Robert Richter Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20120910093018.GO8285@erda.amd.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

perf_event: Switch to internal refcount, fix race with close()

2012-10-02T17:39:07Z

commit a6fa941d94b411bbd2b6421ffbde6db3c93e65ab upstream. Don't mess with file refcounts (or keep a reference to file, for that matter) in perf_event. Use explicit refcount of its own instead. Deal with the race between the final reference to event going away and new children getting created for it by use of atomic_long_inc_not_zero() in inherit_event(); just have the latter free what it had allocated and return NULL, that works out just fine (children of siblings of something doomed are created as singletons, same as if the child of leader had been created and immediately killed). Signed-off-by: Al Viro Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20120820135925.GG23464@ZenIV.linux.org.uk Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

perf: Limit callchains to 127

2012-06-06T15:08:00Z

Stack depth of 255 seems excessive, given that copy_from_user_nmi() could be slow. Signed-off-by: Arun Sharma Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1334961696-19580-3-git-send-email-asharma@fb.com Signed-off-by: Ingo Molnar

perf tools: Check if callchain is corrupted

2012-05-31T14:20:34Z

We faced segmentation fault on perf top -G at very high sampling rate due to a corrupted callchain. While the root cause was not revealed (I failed to figure it out), this patch tries to protect us from the segfault on such cases. Reported-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Sunjin Yang Link: http://lkml.kernel.org/r/1338443007-24857-2-git-send-email-namhyung.kim@lge.com Signed-off-by: Arnaldo Carvalho de Melo

Revert "sched, perf: Use a single callback into the scheduler"

2012-05-23T15:40:51Z

This reverts commit cb04ff9ac424 ("sched, perf: Use a single callback into the scheduler"). Before this change was introduced, the process switch worked like this (wrt. to perf event schedule): schedule (prev, next) - schedule out all perf events for prev - switch to next - schedule in all perf events for current (next) After the commit, the process switch looks like: schedule (prev, next) - schedule out all perf events for prev - schedule in all perf events for (next) - switch to next The problem is, that after we schedule perf events in, the pmu is enabled and we can receive events even before we make the switch to next - so "current" still being prev process (event SAMPLE data are filled based on the value of the "current" process). Thats exactly what we see for test__PERF_RECORD test. We receive SAMPLES with PID of the process that our tracee is scheduled from. Discussed with Peter Zijlstra: > Bah!, yeah I guess reverting is the right thing for now. Sad > though. > > So by having the two hooks we have a black-spot between them > where we receive no events at all, this black-spot covers the > hand-over of current and we thus don't receive the 'wrong' > events. > > I rather liked we could do away with both that black-spot and > clean up the code a little, but apparently people rely on it. Signed-off-by: Jiri Olsa Acked-by: Peter Zijlstra Cc: acme@redhat.com Cc: paulus@samba.org Cc: cjashfor@linux.vnet.ibm.com Cc: fweisbec@gmail.com Cc: eranian@google.com Link: http://lkml.kernel.org/r/20120523111302.GC1638@m.brq.redhat.com Signed-off-by: Ingo Molnar

sched, perf: Use a single callback into the scheduler

2012-05-09T13:23:17Z

We can easily use a single callback for both sched-in and sched-out. This reduces the code footprint in the scheduler path as well as removes the PMU black spot otherwise present between the out and in callback. Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-o56ajxp1edwqg6x9d31wb805@git.kernel.org Signed-off-by: Ingo Molnar

perf: Pass last sampling period to perf_sample_data_init()

2012-05-09T13:23:12Z

We always need to pass the last sample period to perf_sample_data_init(), otherwise the event distribution will be wrong. Thus, modifiyng the function interface with the required period as argument. So basically a pattern like this: perf_sample_data_init(&data, ~0ULL); data.period = event->hw.last_period; will now be like that: perf_sample_data_init(&data, ~0ULL, event->hw.last_period); Avoids unininitialized data.period and simplifies code. Signed-off-by: Robert Richter Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1333390758-10893-3-git-send-email-robert.richter@amd.com Signed-off-by: Ingo Molnar

perf: Move mmap page data_head offset assertion out of header

2012-03-24T07:46:59Z

Having the build time assertion in header is making the perf build fail on x86 with: ../../include/linux/perf_event.h:411:32: error: variably modified \ ‘__assert_mmap_data_head_offset’ at file scope [-Werror] I'm moving the build time validation out of the header, because I think it's better than to lessen the perf build warn/error check. Signed-off-by: Jiri Olsa Cc: acme@redhat.com Cc: a.p.zijlstra@chello.nl Cc: paulus@samba.org Cc: cjashfor@linux.vnet.ibm.com Cc: fweisbec@gmail.com Link: http://lkml.kernel.org/r/1332513680-7870-1-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar

perf: Fix mmap_page capabilities and docs

2012-03-23T08:52:16Z

Complete the syscall-less self-profiling feature and address all complaints, namely: - capabilities, so we can detect what is actually available at runtime Add a capabilities field to perf_event_mmap_page to indicate what is actually available for use. - on x86: RDPMC weirdness due to being 40/48 bits and not sign-extending properly. - ABI documentation as to how all this stuff works. Also improve the documentation for the new features. Signed-off-by: Peter Zijlstra Cc: Stephane Eranian Cc: Vince Weaver Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Link: http://lkml.kernel.org/r/1332433596.2487.33.camel@twins Signed-off-by: Ingo Molnar

perf: Adding sysfs group format attribute for pmu device

2012-03-16T17:06:06Z

Adding sysfs group 'format' attribute for pmu device that contains a syntax description on how to construct raw events. The event configuration is described in following struct pefr_event_attr attributes: config config1 config2 Each sysfs attribute within the format attribute group, describes mapping of name and bitfield definition within one of above attributes. eg: "/sys/.../format/event" contains "config:0-7" "/sys/.../format/umask" contains "config:8-15" "/sys/.../format/usr" contains "config:16" the attribute value syntax is: line: config ':' bits config: 'config' | 'config1' | 'config2" bits: bits ',' bit_term | bit_term bit_term: VALUE '-' VALUE | VALUE Adding format attribute definitions for x86 cpu pmus. Acked-by: Peter Zijlstra Signed-off-by: Peter Zijlstra Signed-off-by: Jiri Olsa Link: http://lkml.kernel.org/n/tip-vhdk5y2hyype9j63prymty36@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo