Commit Graph

1986 Commits

Author SHA1 Message Date
Ingo Molnar eae7a755ee perf tools, x86: Build perf on older user-space as well
On ancient systems I get this build failure:

  util/../../../arch/x86/include/asm/unistd.h:67:29: error: asm/unistd_64.h: No such file or directory
  In file included from util/cache.h:7,
                   from builtin-test.c:8:
  util/../perf.h: In function ‘sys_perf_event_open’:In file included from util/../perf.h:16
  perf.h:170: error: ‘__NR_perf_event_open’ undeclared (first use in this function)

The reason is that this old system does not have the split
unistd.h headers yet, from which to pick up the syscall
definitions.

Add the syscall numbers to the already existing i386 and x86_64
blocks in perf.h, and also provide empty include file stubs.

With this patch perf builds and works fine on 5 years old
user-space as well.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/n/tip-jctwg64le1w47tuaoeyftsg9@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-03-14 12:42:34 -03:00
Arnaldo Carvalho de Melo e7f01d1e3d perf tools: Use scnprintf where applicable
Several places were expecting that the value returned was the number of
characters printed, not what would be printed if there was space.

Fix it by using the scnprintf and vscnprintf variants we inherited from
the kernel sources.

Some corner cases where the number of printed characters were not
accounted were fixed too.

Reported-by: Anton Blanchard <anton@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/n/tip-kwxo2eh29cxmd8ilixi2005x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-03-14 12:36:19 -03:00
Anton Blanchard b832796caa perf tools: Incorrect use of snprintf results in SEGV
I have a workload where perf top scribbles over the stack and we SEGV.
What makes it interesting is that an snprintf is causing this.

The workload is a c++ gem that has method names over 3000 characters
long, but snprintf is designed to avoid overrunning buffers. So what
went wrong?

The problem is we assume snprintf returns the number of characters
written:

    ret += repsep_snprintf(bf + ret, size - ret, "[%c] ", self->level);
...
    ret += repsep_snprintf(bf + ret, size - ret, "%s", self->ms.sym->name);

Unfortunately this is not how snprintf works. snprintf returns the
number of characters that would have been written if there was enough
space. In the above case, if the first snprintf returns a value larger
than size, we pass a negative size into the second snprintf and happily
scribble over the stack. If you have 3000 character c++ methods thats a
lot of stack to trample.

This patch fixes repsep_snprintf by clamping the value at size - 1 which
is the maximum snprintf can write before adding the NULL terminator.

I get the sinking feeling that there are a lot of other uses of snprintf
that have this same bug, we should audit them all.

Cc: David Ahern <dsahern@gmail.com>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/20120307114249.44275ca3@kryten
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-03-14 12:36:19 -03:00
Stephane Eranian 8aa8a7c80c perf record: Fix buffer overrun bug in tracepoint_id_to_path()
This patch fixes a buffer overrun bug in
tracepoint_id_to_path(). The bug manisfested itself as a memory
error reported by perf record. I ran into it with perf sched:

 $ perf sched rec noploop 2 noploop for 2 seconds
 [ perf record: Woken up 14 times to write data ]
 [ perf record: Captured and wrote 42.701 MB perf.data (~1865622 samples) ]
 Fatal: No memory to alloc tracepoints list

It turned out that tracepoint_id_to_path() was reading the
tracepoint id using read() but the buffer was not large enough
to include the \n terminator for id with 4 digits or more.

The patch fixes the problem by extending the buffer to a more
reasonable size covering all possible id length include \n
terminator. Note that atoll() stops at the first non digit
character, thus it is not necessary to clear the buffer between
each read.

Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: fweisbec@gmail.com
Cc: dsahern@gmail.com
Link: http://lkml.kernel.org/r/20120313155102.GA6465@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-13 17:01:28 +01:00
Arnaldo Carvalho de Melo bc76efe645 perf tools: Handle kernels that don't support attr.exclude_{guest,host}
Just fall back to resetting those fields, if set, warning the user that
that feature is not available.

If guest samples appear they will just be discarded because no struct
machine will be found and thus the event will be accounted as not
handled and dropped, see 0c09571.

Reported-by: Namhyung Kim <namhyung@gmail.com>
Tested-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-vuwxig36mzprl5n7nzvnxxsh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-03-03 12:19:56 -03:00
Joerg Roedel 8f54ed4a2d perf tools: Change perf_guest default back to false
Setting perf_guest to true by default makes no sense because the perf
subcommands can not setup guest symbol information and thus not process
and guest samples. The only exception is perf-kvm which changes the
perf_guest value on its own.  So change the default for perf_guest back
to false.

Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328893505-4115-3-git-send-email-joerg.roedel@amd.com
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-03-03 12:13:41 -03:00
David Ahern 6e557a6adf perf record: No build id option fails
A recent refactoring of perf-record introduced the following:

perf record -a -B
Couldn't generating buildids. Use --no-buildid to profile anyway.
sleep: Terminated

I believe the triple negative was meant to be only a double negative.
:-) While I'm there, fixed the grammar on the error message.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1328567272-13190-1-git-send-email-dsahern@gmail.com
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-03-03 11:02:16 -03:00
Prashanth Nageshappa 1c1bc92233 perf probe: Ensure offset provided is not greater than function length without DWARF info too
The 'perf probe' command allows kprobe to be inserted at any offset from
a function start, which results in adding kprobes to unintended
location.  (example: perf probe do_fork+10000 is allowed even though
size of do_fork is ~904).

My previous patch https://lkml.org/lkml/2012/2/24/42 addressed the case
where DWARF info was available for the kernel. This patch fixes the
case where perf probe is used on a kernel without debuginfo available.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/4F4C544D.1010909@linux.vnet.ibm.com
Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-29 18:29:46 -03:00
David Ahern cfbd70c17c perf tools: Ensure comm string is properly terminated
If threads in a multi-threaded process have names shorter than the main
thread the comm for the named threads is not properly terminated.

E.g., for the process 'namedthreads' where each thread is named noploop%d
where %d is the thread number:

Before:
    perf script -f comm,tid,ip,sym,dso
    noploop:4ads 21616  400a49 noploop (/tmp/namedthreads)
The 'ads' in the thread comm bleeds over from the process name.

After:
    perf script -f comm,tid,ip,sym,dso
       noploop:4 21616  400a49 noploop (/tmp/namedthreads)

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1330111898-68071-1-git-send-email-dsahern@gmail.com
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-29 18:29:45 -03:00
Prashanth Nageshappa 26b7952494 perf probe: Ensure offset provided is not greater than function length
The perf probe command allows kprobe to be inserted at any offset from a
function start, which results in adding kprobes to unintended location.

Example: perf probe do_fork+10000 is allowed even though size of do_fork
is ~904.

This patch will ensure probe addition fails when the offset specified is
greater than size of the function.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/4F473F33.4060409@linux.vnet.ibm.com
Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-29 18:29:45 -03:00
Namhyung Kim 30e68bcc67 perf evlist: Return first evsel for non-sample event on old kernel
On old kernels that don't support sample_id_all feature,
perf_evlist__id2evsel() returns NULL for non-sampling events.

This breaks perf top when multiple events are given on command line. Fix
it by using first evsel in the evlist. This will also prevent getting
the same (potential) problem in such new tool/ old kernel combo.

Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1329702447-25045-1-git-send-email-namhyung.kim@lge.com
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-29 18:29:44 -03:00
Naveen N. Rao a4a03fc7ef perf evsel: Fix an issue where perf report fails to show the proper percentage
This patch fixes an issue where perf report shows nan% for certain
perf.data files. The below is from a report for a do_fork probe:

   -nan%           sshd  [kernel.kallsyms]  [k] do_fork
   -nan%    packagekitd  [kernel.kallsyms]  [k] do_fork
   -nan%    dbus-daemon  [kernel.kallsyms]  [k] do_fork
   -nan%           bash  [kernel.kallsyms]  [k] do_fork

A git bisect shows commit f3bda2c as the cause. However, looking back
through the git history, I saw commit 640c03c which seems to have
removed the required initialization for perf_sample->period. The problem
only started showing after commit f3bda2c. The below patch re-introduces
the initialization and it fixes the problem for me.

With the below patch, for the same perf.data:

  73.08%             bash  [kernel.kallsyms]  [k] do_fork
   8.97%      11-dhclient  [kernel.kallsyms]  [k] do_fork
   6.41%             sshd  [kernel.kallsyms]  [k] do_fork
   3.85%        20-chrony  [kernel.kallsyms]  [k] do_fork
   2.56%         sendmail  [kernel.kallsyms]  [k] do_fork

This patch applies over current linux-tip commit 9949284.

Problem introduced in:

$ git describe 640c03c
v2.6.37-rc3-83-g640c03c

Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/20120203170113.5190.25558.stgit@localhost6.localdomain6
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-06 18:59:38 -02:00
Jiri Olsa bf32c9ebc9 perf tools: Fix prefix matching for kernel maps
In some perf ancient versions we used '[kernel.kallsyms._text]' as the
name for the kernel map.

This got changed with commit:
  perf: 'perf kvm' tool for monitoring guest performance from host
  commit a1645ce12a
  Author: Zhang, Yanmin <yanmin_zhang@linux.intel.com>

and we started to use following name '[kernel.kallsyms]_text'.

This name change is important for the report code dealing with ancient
perf data. When processing the kernel map event, we need to recognize
the old naming (dont match the last ']') and initialize the kernel map
correctly.

The subsequent call to maps__set_kallsyms_ref_reloc_sym deals with the
superfluous ']' to get correct symbol name.

Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328461865-6127-1-git-send-email-jolsa@redhat.com
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-06 18:57:39 -02:00
Jiri Olsa 7a0153ee15 perf tools: Fix perf stack to non executable on x86_64
By adding following objects:
  bench/mem-memcpy-x86-64-asm.o
the x86_64 perf binary ended up with executable stack.

The reason was that above object are assembler sourced and is missing the
GNU-stack note section. In such case the linker assumes that the final binary
should not be restricted at all and mark the stack as RWX.

Adding section ".note.GNU-stack" definition to mentioned object, with all
flags disabled, thus omiting this object from linker stack flags decision.

Problem introduced in:

  $ git describe ea7872b
  v2.6.37-rc2-19-gea7872b

Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=783570
Reported-by: Clark Williams <williams@redhat.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1328100848-5630-1-git-send-email-jolsa@redhat.com
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
[ committer note: Backported fix to perf/urgent (3.3-rc2+) ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-06 18:54:06 -02:00
Stephane Eranian 509605dbe9 perf top: Fix number of samples displayed
In recent versions of perf top, pressing the 'e' key to change the
number of displayed samples had no effect.

The number of samples was still dictated by the size of the terminal
(stdio mode). That was quite annoying because typically only the first
dozen samples really matter.

This patch fixes this.

Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120130105037.GA5160@quad
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-30 22:29:49 -02:00
Stephane Eranian d8d9c282a1 perf tools: Fix strlen() bug in perf_event__synthesize_event_type()
The event_type record has a max length for the event name.

It's called MAX_EVENT_NAME.

The name may be truncated to fit the max length. But the header.size still
reflects the original name length. If that length is > MAX_EVENT_NAME, then the
header.size field is bogus. Fix this by using the length of the name after the
potential truncation.

Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120120094912.GA4882@quad
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-30 22:29:12 -02:00
David Daney 0a84f007f9 perf tools: Fix broken build by defining _GNU_SOURCE in Makefile
When building on my Debian/mips system, util/util.c fails to build
because commit 1aed267173 (perf kvm: Do
guest-only counting by default) indirectly includes stdio.h before the
feature selection in util.h is done.  This prevents _GNU_SOURCE in
util.h from enabling the declaration of getline(), from now second
inclusion of stdio.h, and the build is broken.

There is another breakage in util/evsel.c caused by include ordering,
but I didn't fully track down the commit that caused it.

The root cause of all this is an inconsistent definition of _GNU_SOURCE,
so I move the definition into the Makefile so that it is passed to all
invocations of the compiler and used uniformly for all system header
files.  All other #define and #undef of _GNU_SOURCE are removed as they
cause conflicts with the definition passed to the compiler.

All the features.h definitions (_LARGEFILE64_SOURCE _FILE_OFFSET_BITS=64
and _GNU_SOURCE) are needed by the python glue code too, so they are
moved to BASIC_CFLAGS, and the misleading comments about BASIC_CFLAGS
are removed.

This gives me a clean build on x86_64 (fc12) and mips (Debian).

Cc: David Daney <david.daney@cavium.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1326836461-11952-1-git-send-email-ddaney.cavm@gmail.com
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-30 22:19:54 -02:00
Linus Torvalds 83c2f912b4 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  perf tools: Fix compile error on x86_64 Ubuntu
  perf report: Fix --stdio output alignment when --showcpuutilization used
  perf annotate: Get rid of field_sep check
  perf annotate: Fix usage string
  perf kmem: Fix a memory leak
  perf kmem: Add missing closedir() calls
  perf top: Add error message for EMFILE
  perf test: Change type of '-v' option to INCR
  perf script: Add missing closedir() calls
  tracing: Fix compile error when static ftrace is enabled
  recordmcount: Fix handling of elf64 big-endian objects.
  perf tools: Add const.h to MANIFEST to make perf-tar-src-pkg work again
  perf tools: Add support for guest/host-only profiling
  perf kvm: Do guest-only counting by default
  perf top: Don't update total_period on process_sample
  perf hists: Stop using 'self' for struct hist_entry
  perf hists: Rename total_session to total_period
  x86: Add counter when debug stack is used with interrupts enabled
  x86: Allow NMIs to hit breakpoints in i386
  x86: Keep current stack in NMI breakpoints
  ...
2012-01-15 11:26:35 -08:00
Konstantin Khlebnikov 90a5d5af74 mm-tracepoint: fix documentation and examples
We renamed the page-free mm tracepoints.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:41 -08:00
Namhyung Kim 172d1b0b73 perf tools: Fix compile error on x86_64 Ubuntu
The ctype.h include is not needed here and it breaks build on some systems (at
least 64bit Ubuntu 10.04) like below. Just get rid of it.

    CC util/trace-event-info.o
cc1: warnings being treated as errors
util/trace-event-info.c: In function ‘record_file’:
util/trace-event-info.c:192: error: implicit declaration of function ‘pwrite’
util/trace-event-info.c:192: error: nested extern declaration of ‘pwrite’
make: *** [util/trace-event-info.o] Error 1

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1326035430-7621-1-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:34:55 -02:00
Namhyung Kim 0ed35abc2b perf report: Fix --stdio output alignment when --showcpuutilization used
Current perf report output is broken if --showcpuutilization is used.
Combination with -n and/or --show-total-period make things worse.
This patch fixes it as follows:

before:
    48.25%    48.25%     0.00%    sleep  [kernel.kallsyms]  [k] trace_hardirqs_off
    34.99%    34.99%     0.00%    sleep  [kernel.kallsyms]  [k] __find_get_block_slow
    15.99%    15.99%     0.00%    sleep  [kernel.kallsyms]  [k] lock_release_holdtime
     0.77%     0.77%     0.00%    sleep  [kernel.kallsyms]  [k] native_write_msr_safe

after:
    48.25%    48.25%     0.00%    sleep  [kernel.kallsyms]  [k] trace_hardirqs_off
    34.99%    34.99%     0.00%    sleep  [kernel.kallsyms]  [k] __find_get_block_slow
    15.99%    15.99%     0.00%    sleep  [kernel.kallsyms]  [k] lock_release_holdtime
     0.77%     0.77%     0.00%    sleep  [kernel.kallsyms]  [k] native_write_msr_safe

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-8-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:32:51 -02:00
Namhyung Kim 6714a04114 perf annotate: Get rid of field_sep check
The 'field_sep' variable is not set anywhere. Just remove the
conditional.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-7-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:29:34 -02:00
Namhyung Kim 9934525417 perf annotate: Fix usage string
The annotate command doesn't take non-option arguments.

In fact, it can take last argument as a symbol filter though, but that's
a special case and, IMHO, it should be discouraged in favor of the -s
option.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-6-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:28:48 -02:00
Namhyung Kim 1b22859d43 perf kmem: Fix a memory leak
The 'str' should be freed when sort_dimension__add() failed too.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-5-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:27:54 -02:00
Namhyung Kim 8442da1d9f perf kmem: Add missing closedir() calls
The setup_cpunode_map() calls opendir() but misses corresponding
closedir(). Add them.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-4-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:27:06 -02:00
Namhyung Kim cdce445906 perf top: Add error message for EMFILE
When a user tries to open so many events, perf_event_open syscall may
fail with EMFILE. Provide advise for that case.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-3-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:26:11 -02:00
Namhyung Kim c30ab8aa08 perf test: Change type of '-v' option to INCR
The '-v' option is usually defined via OPT_INCR not _INTEGER.  Follow
the trend :).

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-2-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 13:25:00 -02:00
Namhyung Kim 946ef2a245 perf script: Add missing closedir() calls
The get_script_path() calls opendir() but misses corresponding
closedir()'s. Add them.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-1-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-08 12:35:41 -02:00
Linus Torvalds e4e88f31bc Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (185 commits)
  powerpc: fix compile error with 85xx/p1010rdb.c
  powerpc: fix compile error with 85xx/p1023_rds.c
  powerpc/fsl: add MSI support for the Freescale hypervisor
  arch/powerpc/sysdev/fsl_rmu.c: introduce missing kfree
  powerpc/fsl: Add support for Integrated Flash Controller
  powerpc/fsl: update compatiable on fsl 16550 uart nodes
  powerpc/85xx: fix PCI and localbus properties in p1022ds.dts
  powerpc/85xx: re-enable ePAPR byte channel driver in corenet32_smp_defconfig
  powerpc/fsl: Update defconfigs to enable some standard FSL HW features
  powerpc: Add TBI PHY node to first MDIO bus
  sbc834x: put full compat string in board match check
  powerpc/fsl-pci: Allow 64-bit PCIe devices to DMA to any memory address
  powerpc: Fix unpaired probe_hcall_entry and probe_hcall_exit
  offb: Fix setting of the pseudo-palette for >8bpp
  offb: Add palette hack for qemu "standard vga" framebuffer
  offb: Fix bug in calculating requested vram size
  powerpc/boot: Change the WARN to INFO for boot wrapper overlap message
  powerpc/44x: Fix build error on currituck platform
  powerpc/boot: Change the load address for the wrapper to fit the kernel
  powerpc/44x: Enable CRASH_DUMP for 440x
  ...

Fix up a trivial conflict in arch/powerpc/include/asm/cputime.h due to
the additional sparse-checking code for cputime_t.
2012-01-06 17:58:22 -08:00
Sebastian Andrzej Siewior cc5a91e972 perf tools: Add const.h to MANIFEST to make perf-tar-src-pkg work again
Fixes:
|make: *** No rule to make target `../../include/linux/const.h', needed by `builtin-annotate.o'.  Stop.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1324128938-17553-1-git-send-email-sebastian@breakpoint.cc
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-06 15:52:18 -02:00
Joerg Roedel 99320cc824 perf tools: Add support for guest/host-only profiling
To restrict a counter to either host or guest mode this patch introduces
two new event modifiers: G and H.

With G the counter is configured in guest-only mode and with H in
host-only mode.

Cc: Gleb Natapov <gleb@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/n/tip-or5aj3rghy9ngyg882z6kln9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-06 15:49:49 -02:00
Joerg Roedel 1aed267173 perf kvm: Do guest-only counting by default
Make use of exclude_guest and exlude_host in perf-kvm to do only
guest-only counting by default.

Cc: Gleb Natapov <gleb@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
[ committer note: Moved perf_{guest,host} & event_attr_init to util.c ]
[                 so as not to drag more stuff to the python binding]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-06 15:47:37 -02:00
Arnaldo Carvalho de Melo df25f989a4 perf top: Don't update total_period on process_sample
It will be recalculated at __hists__output_resort, to take into account
filters possibly applied by the TUI, etc.

Since we do the percent math only for those entries that will appear on
the TUI instead of for _all_ the entries at decay time, updating it for
each sample makes the entries seem to decay faster when using the
navigation keys (since the screen will be refreshed), as we're not
coalescing the entries that are being batched to be merged at next
resort/decay time, but considering their periods.

Bug introduced in 743eb86.

Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-k0d0rq9a8nqtkqohov8cir72@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-06 15:46:50 -02:00
Arnaldo Carvalho de Melo 12c142781e perf hists: Stop using 'self' for struct hist_entry
Stop using this python/OOP convention, doesn't really helps. Will do
more from time to time till we get it cleaned up in all of /perf.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-me4dyj6s5snh7jr8wb9gzt82@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-06 15:42:52 -02:00
Arnaldo Carvalho de Melo 13d3ee5402 perf hists: Rename total_session to total_period
Nowadays we do it per evsel, not per session (that may have multiple
evsels), so rename it to avoid confusion.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-azsgomr5h4dmaudoogw48w49@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-06 15:42:08 -02:00
Joerg Roedel 9e183426bf perf kvm: Fix copy & paste error in description
The --host option certainly enables host-data collection.

Cc: Avi Kivity <avi@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1317816084-18026-5-git-send-email-gleb@redhat.com
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-03 15:17:14 -02:00
Namhyung Kim 466e2876bc perf script: Kill script_spec__delete
As script_spec__delete() frees given struct script_spec it should not be
called if we failed to allocate the struct. Also it's the only caller of
the function, we can get rid of the function itself.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325000151-4463-4-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-03 15:06:34 -02:00
Namhyung Kim 057a174a06 perf top: Fix a memory leak
The 'buf' should be freed when symbol wasn't found too.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325000151-4463-3-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-03 14:37:19 -02:00
Namhyung Kim 15e6392fee perf stat: Introduce get_ratio_color() helper
The get_ratio_color() returns appropriate color string based on @ratio.
It helps reducing code duplication.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325000151-4463-2-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-03 14:36:32 -02:00
Namhyung Kim 29c9862f1b perf session: Remove impossible condition check
The 'size' cannot be 0 because it was set to 8 on the above line in case
it was 0 and never changed.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325000151-4463-1-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-03 14:35:02 -02:00
Ingo Molnar f232806272 perf tools: Fix feature-bits rework fallout, remove unused variable
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Link: http://lkml.kernel.org/n/tip-lfckuwbl8m1ykb7t9ydsxe4r@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-29 21:26:17 +01:00
Robert Richter 37a058ea00 perf script: Add generic perl handler to process events
The current perf scripting facility only supports tracepoints. This
patch implements a generic perl handler to support other events than
tracepoints too.

This patch introduces a function process_event() that is called by perf
for each sample. The function is called with byte streams as arguments
containing information about the event, its attributes, the sample and
raw data. Perl's unpack() function can easily be used for byte decoding.
The following is the default implementation for process_event() that can
also be generated with perf script:

 # Packed byte string args of process_event():
 #
 # $event:       union perf_event        util/event.h
 # $attr:        struct perf_event_attr  linux/perf_event.h
 # $sample:      struct perf_sample      util/event.h
 # $raw_data:    perf_sample->raw_data   util/event.h

 sub process_event
 {
         my ($event, $attr, $sample, $raw_data) = @_;

         my @event       = unpack("LSS", $event);
         my @attr        = unpack("LLQQQQQLLQQ", $attr);
         my @sample      = unpack("QLLQQQQQLL", $sample);
         my @raw_data    = unpack("C*", $raw_data);

         use Data::Dumper;
         print Dumper \@event, \@attr, \@sample, \@raw_data;
 }

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323969824-9711-4-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 17:05:48 -02:00
Robert Richter b1e5a9bee3 perf tools: Use for_each_set_bit() to iterate over feature flags
This patch introduces the for_each_set_bit() macro and modifies feature
implementation to use it.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-8-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 17:03:36 -02:00
Robert Richter e20960c027 perf tools: Unify handling of features when writing feature section
The features HEADER_TRACE_INFO and HEADER_BUILD_ID are handled
different when writing the feature section. All other features are
simply disabled on failure and writing the section goes on without
returning an error. There is no reason for these special cases. This
patch unifies handling of the features.

This should be ok since all features can be parsed independently.
Offset and size of a feature's block is stored in struct perf_file_
section right after the data block of perf.data (see perf_session__
write_header()). Thus, if a feature does not exist then other features
can be processed anyway.

Also moving special code for HEADER_BUILD_ID out to write_build_id().

v2:
* perf record throws an error now if buildids may not be generated,
  which can be disabled with the --no-buildid option.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-6-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 17:02:22 -02:00
Robert Richter efad14150a perf report: Accept fifos as input file
The default input file for perf report is not handled the same way as
perf record does it for its output file. This leads to unexpected
behavior of perf report, etc. E.g.:

 # perf record -a -e cpu-cycles sleep 2 | perf report | cat
 failed to open perf.data: No such file or directory  (try 'perf record' first)

While perf record writes to a fifo, perf report expects perf.data to be
read. This patch changes this to accept fifos as input file.

Applies to the following commands:

 perf annotate
 perf buildid-list
 perf evlist
 perf kmem
 perf lock
 perf report
 perf sched
 perf script
 perf timechart

Also fixes char const* -> const char* type declaration for filename
strings.

v2:
* Prevent potential null pointer access to input_name in
  builtin-report.c. Needed due to removal of patch "perf report: Setup
  browser if stdout is a pipe"

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-5-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 17:01:03 -02:00
Robert Richter 1b5495043d perf tools: Moving code in some files
Needed for later changes. No modified functionality.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-4-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 16:58:22 -02:00
Robert Richter 002c4fd92d perf tools: Fix out-of-bound access to struct perf_session
If filename is NULL there is an out-of-bound access to struct
perf_session if it would be used with perf_session__open(). Shouldn't
actually happen in current implementation as filename is always !NULL.
Fixing this by always null-terminating filename.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-3-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 16:57:41 -02:00
Robert Richter f7a8a13364 perf tools: Continue processing header on unknown features
A feature may be unknown if perf.data is created and parsed on different
perf tool versions. This should not stop the header to be processed,
instead continue processing it.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-2-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 16:57:09 -02:00
Robert Richter 8cdfa78a88 perf tools: Improve macros for struct feature_ops
Reducing duplication and line size by extending function names for
print and write from a single name.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-7-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 16:56:27 -02:00
Nelson Elhage 41d0d93349 perf: builtin-record: Document and check that mmap_pages must be a power of two.
Now that we automatically point users at it, let's provide them some
guidance so that they hopefully don't just get mysterious EINVAL's
from the kernel.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1324301972-22740-4-git-send-email-nelhage@nelhage.com
Signed-off-by: Nelson Elhage <nelhage@nelhage.com>
[ committer note: Made it work after 50a682c ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-12-23 16:53:58 -02:00