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2012-05-18Merge remote-tracking branch 'tip/perf/urgent' into perf/coreArnaldo Carvalho de Melo1-5/+30
Merge reason: We are going to queue up a dependent patch: "perf tools: Move parse event automated tests to separated object" That depends on: commit e7c72d8 perf tools: Add 'G' and 'H' modifiers to event parsing Conflicts: tools/perf/builtin-stat.c Conflicted with the recent 'perf_target' patches when checking the result of perf_evsel open routines to see if a retry is needed to cope with older kernels where the exclude guest/host perf_event_attr bits were not used. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-16perf target: Rename functions to avoid double negationNamhyung Kim1-7/+7
Rename perf_target__no_{cpu,task} to perf_target__has_{cpu,task} because it's more intuitive and easy to parse (for human beings) when used with negation. The names are came out from David Ahern. It is intended to be a mechanical substitution without any functional change. The perf_target__none remains unchanged since I couldn't find a right name and it is hardly used with negation. Signed-off-by: Namhyung Kim <namhyung.kim@lge.com> Suggested-by: David Ahern <dsahern@gmail.com> Suggested-by: Ingo Molnar <mingo@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1337161549-9870-1-git-send-email-namhyung.kim@lge.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-09perf stat: handle ENXIO error for perf_event_openDavid Ahern1-1/+6
perf stat on PPC currently fails to run: $ perf stat -- sleep 1 Error: open_counter returned with 6 (No such device or address). /bin/dmesg may provide additional information. Fatal: Not all events could be opened. The problem is that until 2.6.37 (behavior changed with commit b0a873e) perf on PPC returns ENXIO when hw_perf_event_init() fails. With this patch we get the expected behavior: $ perf stat -v -- sleep 1 cycles event is not supported by the kernel. stalled-cycles-frontend event is not supported by the kernel. stalled-cycles-backend event is not supported by the kernel. instructions event is not supported by the kernel. branches event is not supported by the kernel. branch-misses event is not supported by the kernel. ... Signed-off-by: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1336490956-57145-1-git-send-email-dsahern@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-09perf stat: handle ENXIO error for perf_event_openDavid Ahern1-1/+6
perf stat on PPC currently fails to run: $ perf stat -- sleep 1 Error: open_counter returned with 6 (No such device or address). /bin/dmesg may provide additional information. Fatal: Not all events could be opened. The problem is that until 2.6.37 (behavior changed with commit b0a873e) perf on PPC returns ENXIO when hw_perf_event_init() fails. With this patch we get the expected behavior: $ perf stat -v -- sleep 1 cycles event is not supported by the kernel. stalled-cycles-frontend event is not supported by the kernel. stalled-cycles-backend event is not supported by the kernel. instructions event is not supported by the kernel. branches event is not supported by the kernel. branch-misses event is not supported by the kernel. ... Signed-off-by: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1336490956-57145-1-git-send-email-dsahern@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-08perf stat: Use perf_evlist__create_mapsNamhyung Kim1-14/+8
Use same function with perf record and top to share the code checks combinations of different switches. Signed-off-by: Namhyung Kim <namhyung.kim@lge.com> Reviewed-by: David Ahern <dsahern@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1336367344-28071-8-git-send-email-namhyung.kim@lge.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-08perf target: Consolidate target task/cpu checkingNamhyung Kim1-6/+6
There are places that check whether target task/cpu is given or not and some of them didn't check newly introduced uid or cpu list. Add and use three of helper functions to treat them properly. Signed-off-by: Namhyung Kim <namhyung.kim@lge.com> Reviewed-by: David Ahern <dsahern@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1336367344-28071-7-git-send-email-namhyung.kim@lge.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-02perf tools: Introduce perf_target__validate() helperNamhyung Kim1-2/+1
The perf_target__validate function is used to check given PID/TID/UID/CPU target options and warn if some combination is impossible. Also this can make some arguments of parse_target_uid() function useless as it is checked before the call via our new helper. Signed-off-by: Namhyung Kim <namhyung.kim@lge.com> Reviewed-by: David Ahern <dsahern@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1335417327-11796-5-git-send-email-namhyung.kim@lge.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-02perf stat: Convert to struct perf_targetNamhyung Kim1-25/+22
Use struct perf_target as it is introduced by previous patch. This is a preparation of further changes. Signed-off-by: Namhyung Kim <namhyung.kim@lge.com> Reviewed-by: David Ahern <dsahern@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1335417327-11796-3-git-send-email-namhyung.kim@lge.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-01perf stat: Fix case where guest/host monitoring is not supported by kernelStephane Eranian1-4/+29
By default, perf stat sets exclude_guest = 1. But when you run perf on a kernel which does not support host/guest filtering, then you get an error saying the event in unsupported. This comes from the fact that when the perf_event_attr struct passed by the user is larger than the one known to the kernel there is safety check which ensures that all unknown bits are zero. But here, exclude_guest is 1 (part of the unknown bits) and thus the perf_event_open() syscall return EINVAL. To my surprise, running perf record on the same kernel did not exhibit the problem. The reason is that perf record handles the problem by catching the error and retrying with guest/host excludes set to zero. For some reason, this was not done with perf stat. This patch fixes this problem. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Joerg Roedel <joro@8bytes.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Richter <robert.richter@amd.com> Link: http://lkml.kernel.org/r/20120427124538.GA7230@quad Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-04-12perf stat: Declare some references staticRobert Richter1-13/+13
This references are not exported, use static declaration. Signed-off-by: Robert Richter <robert.richter@amd.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1333643188-26895-4-git-send-email-robert.richter@amd.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-03-16perf stat: Fix event grouping on forked taskNamhyung Kim1-1/+1
When event group is enabled for forked task (i.e. no target task was specified) all events were disabled and marked ->enable_on_exec. However they are not counted at all since only group leader will be enabled on exec actually. So the result looked like below: $ ./perf stat --group -- sleep 1 Performance counter stats for 'sleep 1': 0.554926 task-clock # 0.001 CPUs utilized <not counted> context-switches <not counted> CPU-migrations <not counted> page-faults <not counted> cycles <not supported> stalled-cycles-frontend <not supported> stalled-cycles-backend <not counted> instructions <not counted> branches <not counted> branch-misses 1.001228093 seconds time elapsed Fix it by disabling group leader only. Cc: Ingo Molnar <mingo@elte.hu> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1331887340-32448-1-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>
2012-02-14perf tools: Allow multiple threads or processes in record, stat, topDavid Ahern1-15/+16
Allow a user to collect events for multiple threads or processes using a comma separated list. e.g., collect data on a VM and its vhost thread: perf top -p 21483,21485 perf stat -p 21483,21485 -ddd perf record -p 21483,21485 or monitoring vcpu threads perf top -t 21488,21489 perf stat -t 21488,21489 -ddd perf record -t 21488,21489 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/1328718772-16688-1-git-send-email-dsahern@gmail.com Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-07perf stat: Align scaled output of cpu-clockNamhyung Kim1-0/+2
The output of cpu-clock event is controlled in nsec_printout(), but its alignment was broken: Performance counter stats for 'sleep 1': 6,038,774 instructions # 0.00 insns per cycle 180 faults # 0.007 K/sec [99.95%] 1,282,201 branches # 0.053 M/sec [99.84%] 24126.221811 cpu-clock [99.62%] 24121.689540 task-clock # 24.098 CPUs utilized [99.52%] 1.001001017 seconds time elapsed This patch fixes this: Performance counter stats for 'sleep 1': 13,540,843 instructions # 0.00 insns per cycle 180 faults # 0.007 K/sec [99.94%] 2,875,386 branches # 0.119 M/sec [99.82%] 24144.221137 cpu-clock [99.61%] 24133.515366 task-clock # 24.109 CPUs utilized [99.52%] 1.001020946 seconds time elapsed Cc: Ingo Molnar <mingo@elte.hu> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1328514285-26232-2-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>
2012-02-07perf stat: Adjust print unitNamhyung Kim1-1/+7
The default 'M/sec' unit is not useful if the result is small enough. Adjust it dynamically according to the value. Cc: Ingo Molnar <mingo@elte.hu> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1328514285-26232-1-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>
2012-01-25perf tools: Introduce per user viewArnaldo Carvalho de Melo1-1/+1
The new --uid command line option will show only the tasks for a given user, using the proc interface to figure out the existing tasks. Kernel work is needed to close races at startup, but this should already be useful in many use cases. 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-bdnspm000gw2l984a2t53o8z@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-01-03perf stat: Introduce get_ratio_color() helperNamhyung Kim1-56/+35
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>
2011-12-20Merge commit 'v3.2-rc6' into perf/coreIngo Molnar1-1/+2
Merge reason: Update with the latest fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05perf stat: Failure with "Operation not supported"Anton Blanchard1-1/+2
perf stat is failing on PowerPC: Error: open_counter returned with 95 (Operation not supported). /bin/dmesg may provide additional information. Fatal: Not all events could be opened. commit 370faf1dd046 (perf stat: Fail softly on unsupported events) added a check for failure returning ENOENT, but the POWER backend returns EOPNOTSUPP. It looks like alpha, blackfin and mips do the same. With the patch applied, things work as expected: Performance counter stats for '/bin/true': 0.362176 task-clock # 0.623 CPUs utilized 0 context-switches # 0.000 M/sec 0 CPU-migrations # 0.000 M/sec 28 page-faults # 0.077 M/sec 1,677,020 cycles # 4.630 GHz <not supported> stalled-cycles-frontend <not supported> stalled-cycles-backend 431,220 instructions # 0.26 insns per cycle 101,889 branches # 281.325 M/sec 4,145 branch-misses # 4.07% of all branches 0.000581361 seconds time elapsed Cc: <stable@kernel.org> # 3.0+ Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.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/20111202093833.5fef7226@kryten Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-11-29perf evlist: Always do automatic allocation of pollfd and mmap structuresArnaldo Carvalho de Melo1-2/+1
At first tools were required to do that, but while writing the python bindings to simplify the API I made them auto-allocate when needed. This just makes record, stat and top use that auto allocation, simplifying them a bit. 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-iokhcvkzzijr3keioubx8hlq@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-11-28perf evlist: Introduce perf_evlist__add_attrsArnaldo Carvalho de Melo1-33/+7
Replacing the open coded equivalents in 'perf stat'. 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-1btwadnf2tds2g07hsccsdse@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-10-26perf evlist: Fix grouping of multiple eventsArnaldo Carvalho de Melo1-6/+14
The __perf_evsel__open routing was grouping just the threads for that specific events per cpu when we want to group all threads in all events to the first fd opened on that cpu. So pass the xyarray with the first event, where the other events will be able to get that first per cpu fd. At some point top and record will switch to using perf_evlist__open that takes care of this detail and probably will also handle the fallback from hw to soft counters, etc. Reported-by: Deng-Cheng Zhu <dczhu@mips.com> Tested-by: Deng-Cheng Zhu <dczhu@mips.com> 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-ebm34rh098i9y9v4cytfdp0x@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-30perf tools: Make stat/record print fatal signals of the target programAndi Kleen1-0/+2
When a program crashes under perf there is no message about it, unlike when running it from bash. This can be confusing and lead to wrong actions during debugging. Print fatal signals in perf stat/record. Thanks to Furat Afram for finding the problem originally Link: http://lkml.kernel.org/r/1316122302-24306-1-git-send-email-andi@firstfloor.org Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-30perf stat: Fix spelling in commentJim Cromie1-1/+1
Link: http://lkml.kernel.org/r/1315437244-3788-6-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-30perf stat: Allow tab as cvs delimiterJim Cromie1-2/+4
If option -x '\t' is given, convert '\t' to "\t". This makes cvs printing more flexible. Link: http://lkml.kernel.org/r/1315437244-3788-5-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-30perf stat: Suppress printing std-dev when its 0Jim Cromie1-1/+1
For pretty output only (preserve column for cvs output), dont print std-deviation when its 0.00. Do this based upon value, instead of checking for --no-aggr, since the stats could conceivably be computed over the runs on each CPU, and theres no reason to preclude that. Link: http://lkml.kernel.org/r/1315437244-3788-4-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-30perf stat: Fix +- nan% in --no-aggr runsJim Cromie1-2/+7
Without this patch, running: $ sudo ./perf stat -r20 --no-aggr -a perl -e '$i++ for 1..100000' I get computations like this: CPU0 12.488247 task-clock # 1.224 CPUs utilized ( +- -nan% ) CPU1 12.488909 task-clock # 1.225 CPUs utilized ( +- -nan% ) CPU2 12.500221 task-clock # 1.226 CPUs utilized ( +- -nan% ) CPU3 12.481713 task-clock # 1.224 CPUs utilized ( +- -nan% ) but with patch, I get: CPU0 8.233682 task-clock # 0.754 CPUs utilized ( +- 0.00% ) CPU1 8.226318 task-clock # 0.754 CPUs utilized ( +- 0.00% ) CPU2 8.210737 task-clock # 0.752 CPUs utilized ( +- 0.00% ) CPU3 8.201691 task-clock # 0.751 CPUs utilized ( +- 0.00% ) Note that without --no-aggr, I get non-0 statistics both before and after patch: 231.986022 task-clock # 4.030 CPUs utilized ( +- 0.97% ) 212 context-switches # 0.001 M/sec ( +- 12.07% ) 9 CPU-migrations # 0.000 M/sec ( +- 25.80% ) 466 page-faults # 0.002 M/sec ( +- 3.23% ) 174,318,593 cycles # 0.751 GHz ( +- 1.06% ) I couldnt see anything wrong in the caller, so fixed it in stddev_stats(). ISTM that 0.00 is better than nan, since perf stat was passed -A (--no-aggr) so no standard deviation should be expected, and nan is suggestive of a deeper error. When running with --no-aggr, perhaps we should suppress the statistics printing entirely, or do so when they are 0.00. Link: http://lkml.kernel.org/r/1315437244-3788-3-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-30perf stat: Add --log-fd <N> option to redirect stderr elsewhereJim Cromie1-0/+14
This perf stat option emulates valgrind's --log-fd option, allowing the user to send perf results elsewhere, and leaving stderr for use by the program under test. This complements --output file option, and is mutually exclusive with it. 3>results perf stat --log-fd 3 -- $cmd 3>>results perf stat --log-fd 3 --append -- $cmd The perl distro's make test.valgrind target uses valgrind's --log-fd option, I've adapted it to invoke perf also, and tested this patch there. Link: http://lkml.kernel.org/r/1315437244-3788-2-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-18Merge branch 'perf/core' of ↵Ingo Molnar1-63/+92
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core Conflicts: tools/perf/builtin-stat.c
2011-08-18perf stat: Add -o and --append optionsStephane Eranian1-63/+92
This patch adds an option (-o) to save the output of perf stat into a file. You could do this with perf record but not with perf stat. Instead, you had to fiddle with stderr to save the counts into a separate file. The patch also adds the --append option so that results can be concatenated into a single file across runs. Each run of the tool is clearly separated by a comment line starting with a hash mark. The -A option of perf record is already used by perf stat, so we only add a long option. $ perf stat -o res.txt date $ cat res.txt Performance counter stats for 'date': 0.791306 task-clock # 0.668 CPUs utilized 2 context-switches # 0.003 M/sec 0 CPU-migrations # 0.000 M/sec 197 page-faults # 0.249 M/sec 1878143 cycles # 2.373 GHz <not supported> stalled-cycles-frontend <not supported> stalled-cycles-backend 1083367 instructions # 0.58 insns per cycle 193027 branches # 243.935 M/sec 9014 branch-misses # 4.67% of all branches 0.001184746 seconds time elapsed The option can be combined with -x to make the output file much easier to parse. Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20110815202233.GA18535@quad Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-18perf tools: Add group event scheduling option to perf record/statLin Ming1-2/+5
Group event scheduling command line option is missing in perf record/stat. Add it to perf record/stat, which is same as in perf top. Reported-by: Andi Kleen <andi@firstfloor.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1313577727.2754.5.camel@hp6530s Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-07-21perf tools: De-opt the parse_events functionJiri Olsa1-1/+1
Moving out the option parameter from parse_events function, and adding new parse_events_option function instead. The option parameter is used only to carry "struct perf_evlist" pointer for chaining new events. Putting it away, enable us to call parse_events from other places without using the option parameter. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: acme@redhat.com Cc: a.p.zijlstra@chello.nl Cc: paulus@samba.org Link: http://lkml.kernel.org/r/1310635534-4013-2-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-01perf stat: Add noise output for csv modeZhengyu He1-3/+6
Previously, when you want perf-stat to output the statistics in csv mode, no information of the noise will be printed out. For example right now we output this --repeat information: ./perf stat -r3 -x, sleep 1 1.164789,task-clock 8,context-switches 0,CPU-migrations 219,page-faults 3337800,cycles With this patch, the output will be appended with an additional entry for the noise value: ./perf stat -r3 -x, sleep 1 1.164789,task-clock,3.75% 8,context-switches,75.00% 0,CPU-migrations,100.00% 219,page-faults,0.00% 3337800,cycles,3.36% Signed-off-by: Zhengyu He <zhengyuh@google.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Stephane Eranian <eranian@google.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/1308861942-4945-1-git-send-email-zhengyuh@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-06-02perf stat: clarify unsupported events from uncounted eventsDavid Ahern1-2/+7
perf stat continues running even if the event list contains counters that are not supported. The resulting output then contains <not counted> for those events which gets confusing as to which events are supported, but not counted and which are not supported. Before: perf stat -ddd -- sleep 1 Performance counter stats for 'sleep 1': 0.571283 task-clock # 0.001 CPUs utilized 1 context-switches # 0.002 M/sec 0 CPU-migrations # 0.000 M/sec 157 page-faults # 0.275 M/sec 1,037,707 cycles # 1.816 GHz <not counted> stalled-cycles-frontend <not counted> stalled-cycles-backend 654,499 instructions # 0.63 insns per cycle 136,129 branches # 238.286 M/sec <not counted> branch-misses <not counted> L1-dcache-loads <not counted> L1-dcache-load-misses <not counted> LLC-loads <not counted> LLC-load-misses <not counted> L1-icache-loads <not counted> L1-icache-load-misses <not counted> dTLB-loads <not counted> dTLB-load-misses <not counted> iTLB-loads <not counted> iTLB-load-misses <not counted> L1-dcache-prefetches <not counted> L1-dcache-prefetch-misses 1.001004836 seconds time elapsed After: perf stat -ddd -- sleep 1 Performance counter stats for 'sleep 1': 1.350326 task-clock # 0.001 CPUs utilized 2 context-switches # 0.001 M/sec 0 CPU-migrations # 0.000 M/sec 157 page-faults # 0.116 M/sec 11,986 cycles # 0.009 GHz <not supported> stalled-cycles-frontend <not supported> stalled-cycles-backend 496,986 instructions # 41.46 insns per cycle 138,065 branches # 102.246 M/sec 7,245 branch-misses # 5.25% of all branches <not counted> L1-dcache-loads <not counted> L1-dcache-load-misses <not counted> LLC-loads <not counted> LLC-load-misses <not counted> L1-icache-loads <not counted> L1-icache-load-misses <not counted> dTLB-loads <not counted> dTLB-load-misses <not counted> iTLB-loads <not counted> iTLB-load-misses <not counted> L1-dcache-prefetches <not supported> L1-dcache-prefetch-misses 1.002397333 seconds time elapsed v1->v2: changed supported type from int to bool v2->v3 fixed vertical alignment of new struct element 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/1306767359-13221-1-git-send-email-dsahern@gmail.com Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-05-19perf stat: Add more cache-miss percentage printoutsIngo Molnar1-2/+136
Print out the cache-miss percentage as well if the cache refs were collected, for all the generic cache event types. Before: 11,103,723,230 dTLB-loads # 622.471 M/sec ( +- 0.30% ) 87,065,337 dTLB-load-misses # 4.881 M/sec ( +- 0.90% ) After: 11,353,713,242 dTLB-loads # 626.020 M/sec ( +- 0.35% ) 113,393,472 dTLB-load-misses # 1.00% of all dTLB cache hits ( +- 0.49% ) Also ASCII color highlight too high percentages, them when it's executed on the console. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/n/tip-lkhwxsevdbd9a8nymx0vxc3y@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-19perf stat: Add -d -d and -d -d -d options to show more CPU eventsIngo Molnar1-55/+154
Print even more detailed statistics if requested via perf stat -d: -d: detailed events, L1 and LLC data cache -d -d: more detailed events, dTLB and iTLB events -d -d -d: very detailed events, adding prefetch events Full output looks like this now: Performance counter stats for '/home/mingo/hackbench 10' (5 runs): 1703.674707 task-clock # 8.709 CPUs utilized ( +- 4.19% ) 49,068 context-switches # 0.029 M/sec ( +- 16.66% ) 8,303 CPU-migrations # 0.005 M/sec ( +- 24.90% ) 17,397 page-faults # 0.010 M/sec ( +- 0.46% ) 2,345,389,239 cycles # 1.377 GHz ( +- 4.61% ) [55.90%] 1,884,503,527 stalled-cycles-frontend # 80.35% frontend cycles idle ( +- 5.67% ) [50.39%] 743,919,737 stalled-cycles-backend # 31.72% backend cycles idle ( +- 8.75% ) [49.91%] 1,314,416,379 instructions # 0.56 insns per cycle # 1.43 stalled cycles per insn ( +- 2.53% ) [60.87%] 272,592,567 branches # 160.003 M/sec ( +- 1.74% ) [56.56%] 3,794,846 branch-misses # 1.39% of all branches ( +- 6.59% ) [58.50%] 449,982,778 L1-dcache-loads # 264.125 M/sec ( +- 2.47% ) [49.88%] 22,404,961 L1-dcache-load-misses # 4.98% of all L1-dcache hits ( +- 6.08% ) [55.05%] 6,204,750 LLC-loads # 3.642 M/sec ( +- 8.91% ) [43.75%] 1,837,411 LLC-load-misses # 1.078 M/sec ( +- 7.27% ) [12.07%] 411,440,421 L1-icache-loads # 241.502 M/sec ( +- 5.60% ) [36.52%] 27,556,832 L1-icache-load-misses # 16.175 M/sec ( +- 7.46% ) [46.72%] 464,067,627 dTLB-loads # 272.392 M/sec ( +- 4.46% ) [54.17%] 10,765,648 dTLB-load-misses # 6.319 M/sec ( +- 3.18% ) [48.68%] 1,273,080,386 iTLB-loads # 747.256 M/sec ( +- 3.38% ) [47.53%] 117,481 iTLB-load-misses # 0.069 M/sec ( +- 14.99% ) [47.01%] 4,590,653 L1-dcache-prefetches # 2.695 M/sec ( +- 4.49% ) [46.19%] 1,712,660 L1-dcache-prefetch-misses # 1.005 M/sec ( +- 3.75% ) [44.82%] 0.195622057 seconds time elapsed ( +- 6.84% ) Also clean up the attribute construction code to be appending, and factor it out into add_default_attributes(). Tweak the coverage percentage printout a bit, so that it's easier to view it alongside the +- sttddev colum. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/n/tip-to3kgu04449s64062val8b62@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-30perf stat: Tell user about unsupported events in the listDavid Ahern1-1/+5
Similar to perf-record, tell user about unsupported events that will not be counted if invoked in verbose mode. e.g., $ perf stat -e dTLB-prefetch-misses -v -- sleep 1 dTLB-prefetch-misses event is not supported by the kernel. dTLB-prefetch-misses: 0 0 0 Performance counter stats for 'sleep 1': <not counted> dTLB-prefetch-misses 1.001884783 seconds time elapsed Signed-off-by: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/1304114655-10600-1-git-send-email-dsahern@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-29perf stat: Fail softly on unsupported eventsIngo Molnar1-3/+1
David Ahern reported this perf stat failure: > # /tmp/build-perf/perf stat -- sleep 1 > Error: stalled-cycles-frontend event is not supported. > Fatal: Not all events could be opened. > > This is a Dell R410 with an E5620 processor. Fail in a softer fashion on unknown/unsupported events. Reported-by: David Ahern <dsahern@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n006io7hjpn1dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-29perf stat: Leave more room for percentagesIngo Molnar1-11/+11
Triple digit percentages do not fit otherwise. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n005io7hjpn1dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-29perf stat: Adjust stall cycles warning percentagesIngo Molnar1-4/+4
Adjust to color thresholds to better match the percentages seen in real workloads. Both are now a bit more sensitive. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n004io7hjpn1dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-29perf stat: Analyze front-end and back-end stall countsIngo Molnar1-6/+35
Sample output: Performance counter stats for './loop_1b': 873.691065 task-clock # 1.000 CPUs utilized 1 context-switches # 0.000 M/sec 1 CPU-migrations # 0.000 M/sec 96 page-faults # 0.000 M/sec 2,012,637,222 cycles # 2.304 GHz (66.58%) 1,001,397,911 stalled-cycles-frontend # 49.76% frontend cycles idle (66.58%) 7,523,398 stalled-cycles-backend # 0.37% backend cycles idle (66.76%) 2,004,551,046 instructions # 1.00 insns per cycle # 0.50 stalled cycles per insn (66.80%) 1,001,304,992 branches # 1146.063 M/sec (66.76%) 39,453 branch-misses # 0.00% of all branches (66.64%) 0.874046121 seconds time elapsed Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n003io7hjpn1dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-29perf tools: Add front-end and back-end stalled cycles supportIngo Molnar1-4/+6
Update perf tooling to deal with front-end and back-end stalled cycles events. Add both the default 'perf stat' output. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n002io7hjpn1dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-28perf stat: Fix compatibility behaviorIngo Molnar1-1/+4
Instead of failing on an unknown event, when new perf stat is run on older kernels: $ ./perf stat true Error: open_counter returned with 22 (Invalid argument). /bin/dmesg may provide additional information. Fatal: Not all events could be opened. Just ignore EINVAL and ENOSYS, we'll print the results as not counted: Performance counter stats for 'true': 0.239483 task-clock # 0.493 CPUs utilized 0 context-switches # 0.000 M/sec 0 CPU-migrations # 0.000 M/sec 86 page-faults # 0.359 M/sec 704,766 cycles # 2.943 GHz <not counted> stalled-cycles 381,961 instructions # 0.54 insns per cycle 69,626 branches # 290.735 M/sec 4,594 branch-misses # 6.60% of all branches 0.000485883 seconds time elapsed Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n1eqio5hjpn3dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-28perf stat: Add --sync/-S optionIngo Molnar1-0/+7
--sync will tell perf stat to run sync() before starting a command. This allows IO-heavy tests to be used with --repeat, without one iteration impacting the other. Elapsed time will stabilize for example: before: 3.971525714 seconds time elapsed ( +- 8.56% ) after: 3.211098537 seconds time elapsed ( +- 1.52% ) So measurements will be more accurate. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n1eqio7hjpn1dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-27perf stat: Fix printout vertical alignmentIngo Molnar1-1/+1
Before: | | Performance counter stats for '/home/mingo/hackbench 20' (5 runs): | | 71,321,607 instructions:u # 0.42 insns per cycle ( +- 0.00% ) | 168,040,009 cycles:u # 0.000 GHz ( +- 0.81% ) | | 1.468002368 seconds time elapsed ( +- 1.33% ) | After: | | Performance counter stats for '/home/mingo/hackbench 20' (5 runs): | | 71,321,607 instructions:u # 0.42 insns per cycle ( +- 0.00% ) | 168,040,009 cycles:u # 0.000 GHz ( +- 0.81% ) | | 1.468002368 seconds time elapsed ( +- 1.33% ) | The last column (stddev noise) is properly aligned, vertically. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-7y40wib8n1eqio7hjpn0dsrm@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26perf stat: Add -d/--detailed flag to run with a lot of eventsIngo Molnar1-8/+60
Add the new -d/--detailed flag, which generates a pretty detailed event list: Performance counter stats for './hackbench 10' (10 runs): 1514.287888 task-clock # 10.897 CPUs utilized ( +- 3.05% ) 39,698 context-switches # 0.026 M/sec ( +- 12.19% ) 8,147 CPU-migrations # 0.005 M/sec ( +- 16.55% ) 17,918 page-faults # 0.012 M/sec ( +- 0.37% ) 2,944,504,050 cycles # 1.944 GHz ( +- 3.89% ) (32.60%) 1,043,971,283 stalled-cycles # 35.45% of all cycles are idle ( +- 5.22% ) (44.48%) 1,655,906,768 instructions # 0.56 insns per cycle # 0.63 stalled cycles per insn ( +- 1.95% ) (55.09%) 338,832,373 branches # 223.757 M/sec ( +- 1.96% ) (64.47%) 3,892,416 branch-misses # 1.15% of all branches ( +- 5.49% ) (73.12%) 606,410,482 L1-dcache-loads # 400.459 M/sec ( +- 1.29% ) (71.21%) 31,204,395 L1-dcache-load-misses # 5.15% of all L1-dcache hits ( +- 3.04% ) (60.43%) 3,922,751 LLC-loads # 2.590 M/sec ( +- 6.80% ) (46.87%) 5,037,288 LLC-load-misses # 3.327 M/sec ( +- 3.56% ) (13.00%) 0.138966828 seconds time elapsed ( +- 4.11% ) This can be used "at a glance" for narrower analysis. -d can also be used in addition to other -e events, to further expand an event list. Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-cxs98quixs3qyvdqx3goojc4@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26perf stat: Print out miss/hit ratio for L1 data-cache eventsIngo Molnar1-0/+33
Print out this kind of l1-dcache-misses percentage: Performance counter stats for './bw_tcp localhost': 29,956,262,201 cycles # 3.002 GHz (scaled from 85.14%) 8,255,209,558 stalled-cycles # 27.56% of all cycles are idle (scaled from 86.56%) 1,206,130,308 l1-dcache-misses # 40.49% of all L1-dcache hits (scaled from 86.30%) 2,978,756,779 l1-dcache-refs # 298.512 M/sec (scaled from 70.02%) 8,861,956,159 instructions # 0.30 insns per cycle # 0.93 stalled cycles per insn (scaled from 84.27%) 1,644,306,068 branches # 164.782 M/sec (scaled from 86.43%) 74,778,443 branch-misses # 4.55% of all branches (scaled from 70.69%) 9978.695711 task-clock # 0.693 CPUs utilized 14.404347983 seconds time elapsed And color the result depending on the severity of cache-trashing. Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-54gmz0zymaid84zcs7joq02p@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26perf stat: Print branch misses warning colorsIngo Molnar1-7/+24
Print the missed-branches percentage with different warning level ASCII colors, as the percentage passes the 5%/10%/20% thresholds. These thresholds are set to relatively low levels, because on most CPUs even a moderate percentage of branch-misses already shows up as a slowdown. Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-ybqukg7p86leiup7gl03ecgk@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26perf stat: Print stalled cycles warning colorsIngo Molnar1-6/+27
Print the stalled-cycles percentage with different warning level ASCII colors, as the percentage passes the 25%/50%/75% thresholds. Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-e25zz44rcms7mu9az4fu5zp0@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26perf stat: Fix -nan% output in perf stat noise printoutsIngo Molnar1-5/+13
Before: 0 CPU-migrations # 0.000 M/sec ( +- -nan% ) After: 0 CPU-migrations # 0.000 M/sec ( +- 0.00% ) Also factor out the noise printing function. Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-z89h2v1bk1mikcbsf7e6v34q@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26perf stat: Add stalled cycles to the default outputIngo Molnar1-3/+2
The new default output looks like this: Performance counter stats for './loop_1b_instructions': 236.010686 task-clock # 0.996 CPUs utilized 0 context-switches # 0.000 M/sec 0 CPU-migrations # 0.000 M/sec 99 page-faults # 0.000 M/sec 756,487,646 cycles # 3.205 GHz 354,938,996 stalled-cycles # 46.92% of all cycles are idle 1,001,403,797 instructions # 1.32 insns per cycle # 0.35 stalled cycles per insn 100,279,773 branches # 424.895 M/sec 12,646 branch-misses # 0.013 % of all branches 0.236902540 seconds time elapsed We dropped cache-refs and cache-misses and added stalled-cycles - this is a more generic "how well utilized is the CPU" metric. If the stalled-cycles ratio is too high then more specific measurements can be taken to figure out the source of the inefficiency. Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-pbpl2l4mn797s69bclfpwkwn@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>