linux/tools/perf/util
Arnaldo Carvalho de Melo aece948f5d perf evlist: Fix per thread mmap setup
The PERF_EVENT_IOC_SET_OUTPUT ioctl was returning -EINVAL when using
--pid when monitoring multithreaded apps, as we can only share a ring
buffer for events on the same thread if not doing per cpu.

Fix it by using per thread ring buffers.

Tested with:

[root@felicio ~]# tuna -t 26131 -CP | nl
  1                      thread       ctxt_switches
  2    pid SCHED_ rtpri affinity voluntary nonvoluntary             cmd
  3 26131   OTHER     0      0,1  10814276      2397830 chromium-browse
  4  642    OTHER     0      0,1     14688            0 chromium-browse
  5  26148  OTHER     0      0,1    713602       115479 chromium-browse
  6  26149  OTHER     0      0,1    801958         2262 chromium-browse
  7  26150  OTHER     0      0,1   1271128          248 chromium-browse
  8  26151  OTHER     0      0,1         3            0 chromium-browse
  9  27049  OTHER     0      0,1     36796            9 chromium-browse
 10  618    OTHER     0      0,1     14711            0 chromium-browse
 11  661    OTHER     0      0,1     14593            0 chromium-browse
 12  29048  OTHER     0      0,1     28125            0 chromium-browse
 13  26143  OTHER     0      0,1   2202789          781 chromium-browse
[root@felicio ~]#

So 11 threads under pid 26131, then:

[root@felicio ~]# perf record -F 50000 --pid 26131

[root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl
  1 7fa4a2538000-7fa4a25b9000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  2 7fa4a25b9000-7fa4a263a000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  3 7fa4a263a000-7fa4a26bb000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  4 7fa4a26bb000-7fa4a273c000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  5 7fa4a273c000-7fa4a27bd000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  6 7fa4a27bd000-7fa4a283e000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  7 7fa4a283e000-7fa4a28bf000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  8 7fa4a28bf000-7fa4a2940000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
  9 7fa4a2940000-7fa4a29c1000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
 10 7fa4a29c1000-7fa4a2a42000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
 11 7fa4a2a42000-7fa4a2ac3000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
[root@felicio ~]#

11 mmaps, one per thread since we didn't specify any CPU list, so we need one
mmap per thread and:

[root@felicio ~]# perf record -F 50000 --pid 26131
^M
^C[ perf record: Woken up 79 times to write data ]
[ perf record: Captured and wrote 20.614 MB perf.data (~900639 samples) ]

[root@felicio ~]# perf report -D | grep PERF_RECORD_SAMPLE | cut -d/ -f2 | cut -d: -f1 | sort -n | uniq -c | sort -nr | nl
     1	 371310 26131
     2	  96516 26148
     3	  95694 26149
     4	  95203 26150
     5	   7291 26143
     6	     87 27049
     7	     76 661
     8	     60 29048
     9	     47 618
    10	     43 642
[root@felicio ~]#

Ok, one of the threads, 26151 was quiescent, so no samples there, but all the
others are there.

Then, if I specify one CPU:

[root@felicio ~]# perf record -F 50000 --pid 26131 --cpu 1
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.680 MB perf.data (~29730 samples) ]

[root@felicio ~]# perf report -D | grep PERF_RECORD_SAMPLE | cut -d/ -f2 | cut -d: -f1 | sort -n | uniq -c | sort -nr | nl
     1	   8444 26131
     2	   2584 26149
     3	   2518 26148
     4	   2324 26150
     5	    123 26143
     6	      9 661
     7	      9 29048
[root@felicio ~]#

This machine has two cores, so fewer threads appeared on the radar, and:

[root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl
 1 7f484b922000-7f484b9a3000 rwxs 00000000 00:09 4064 anon_inode:[perf_event]
[root@felicio ~]#

Just one mmap, as now we can use just one per-cpu buffer instead of the
per-thread needed in the previous case.

For global profiling:

[root@felicio ~]# perf record -F 50000 -a
^C[ perf record: Woken up 26 times to write data ]
[ perf record: Captured and wrote 7.128 MB perf.data (~311412 samples) ]

[root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl
     1	7fb49b435000-7fb49b4b6000 rwxs 00000000 00:09 4064                       anon_inode:[perf_event]
     2	7fb49b4b6000-7fb49b537000 rwxs 00000000 00:09 4064                       anon_inode:[perf_event]
[root@felicio ~]#

It uses per-cpu buffers.

For just one thread:

[root@felicio ~]# perf record -F 50000 --tid 26148
^C[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.330 MB perf.data (~14426 samples) ]

[root@felicio ~]# perf report -D | grep PERF_RECORD_SAMPLE | cut -d/ -f2 | cut -d: -f1 | sort -n | uniq -c | sort -nr | nl
     1	   9969 26148
[root@felicio ~]#

[root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl
     1	7f286a51b000-7f286a59c000 rwxs 00000000 00:09 4064                       anon_inode:[perf_event]
[root@felicio ~]#

Tested-by: David Ahern <dsahern@gmail.com>
Tested-by: Lin Ming <ming.m.lin@intel.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
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: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/r/20110426204401.GB1746@ghostprotocols.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-05-15 10:02:14 -03:00
..
include perf evsel: Introduce perf_evlist 2011-01-22 19:56:28 -02:00
scripting-engines perf session: Pass evsel in event_ops->sample() 2011-03-23 19:28:58 -03:00
ui perf hists browser: Fix seg fault when annotate null symbol 2011-04-15 12:51:49 -03:00
abspath.c perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
alias.c perf_counter tools: Add more warnings and fix/annotate them 2009-07-01 12:49:48 +02:00
annotate.c perf symbols: Rename dso->origin to dso->symtab_type 2011-03-11 13:28:45 -03:00
annotate.h perf top: Live TUI Annotation 2011-02-22 12:02:07 -03:00
bitmap.c perf tools: Don't use code surrounded by __KERNEL__ 2010-05-02 12:00:44 -03:00
build-id.c perf session: Pass evsel in event_ops->sample() 2011-03-23 19:28:58 -03:00
build-id.h perf annotate: Use build-ids to find the right DSO 2010-05-20 12:15:33 -03:00
cache.h perf tools: Don't fallback to setup_pager unconditionally 2011-01-31 18:08:39 -02:00
callchain.c perf tools: Kill event_t typedef, use 'union perf_event' instead 2011-01-29 16:25:37 -02:00
callchain.h perf tools: Kill event_t typedef, use 'union perf_event' instead 2011-01-29 16:25:37 -02:00
cgroup.c perf: Fix a build error with some GCC versions 2011-04-08 17:40:21 +02:00
cgroup.h perf tool: Add cgroup support 2011-02-16 13:30:48 +01:00
color.c perf hist: Replace ->print() routines by ->snprintf() equivalents 2010-04-02 16:28:15 -03:00
color.h perf hist: Replace ->print() routines by ->snprintf() equivalents 2010-04-02 16:28:15 -03:00
config.c perf buildid: add perfconfig option to specify buildid cache dir 2010-06-05 09:34:04 -03:00
cpumap.c perf tools: Add missing cpu_map__delete() 2011-01-22 19:56:30 -02:00
cpumap.h perf tools: Add missing cpu_map__delete() 2011-01-22 19:56:30 -02:00
ctype.c perf tools: Move graph_line and graph_dotted_line from top 2009-11-23 21:55:20 +01:00
debug.c perf tools: Fixup exit path when not able to open events 2011-03-29 13:40:27 -03:00
debug.h perf tools: Fixup exit path when not able to open events 2011-03-29 13:40:27 -03:00
debugfs.c perf trace: Clean up find_debugfs() 2009-12-28 10:36:36 +01:00
debugfs.h perf tools: Mount debugfs automatically 2009-12-28 10:36:36 +01:00
environment.c
event.c perf symbols: Fix vsyscall symbol lookup 2011-03-28 14:44:15 -03:00
event.h Merge remote branch 'acme/perf/urgent' into perf/core 2011-02-11 11:45:54 -02:00
evlist.c perf evlist: Fix per thread mmap setup 2011-05-15 10:02:14 -03:00
evlist.h perf evlist: Fix per thread mmap setup 2011-05-15 10:02:14 -03:00
evsel.c perf evsel: Fix use of inherit 2011-04-15 12:52:28 -03:00
evsel.h perf evsel: Fix use of inherit 2011-04-15 12:52:28 -03:00
exec_cmd.c perf tools: Makefile: Remove various and sundry cruft 2011-02-18 07:43:06 -02:00
exec_cmd.h perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
generate-cmdlist.sh
header.c perf build-id: Add quirk to deal with perf.data file format breakage 2011-03-23 19:29:40 -03:00
header.h perf header: Stop using 'self' 2011-03-10 11:16:28 -03:00
help.c perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
help.h perf tools: Protect header files with a consistent style 2009-09-24 21:27:51 +02:00
hist.c perf tools: Improve support for sessions with multiple events 2011-03-06 13:13:40 -03:00
hist.h perf session: Pass evsel in event_ops->sample() 2011-03-23 19:28:58 -03:00
hweight.c perf tools: Don't use code surrounded by __KERNEL__ 2010-05-02 12:00:44 -03:00
levenshtein.c
levenshtein.h perf tools: Protect header files with a consistent style 2009-09-24 21:27:51 +02:00
map.c perf tools: Fix 64 bit integer format strings 2011-01-22 23:41:57 -02:00
map.h perf probe: Add basic module support 2010-10-21 16:11:44 -02:00
pager.c perf_counter tools: Remove dead code 2009-06-27 06:06:39 +02:00
parse-events.c perf script: Add support for H/W and S/W events 2011-03-14 17:07:20 -03:00
parse-events.h perf script: Add support for H/W and S/W events 2011-03-14 17:07:20 -03:00
parse-options.c perf options: Type check all the remaining OPT_ variants 2010-05-17 16:22:41 -03:00
parse-options.h perf options: add OPT_CALLBACK_DEFAULT_NOOPT 2010-12-06 15:33:29 -02:00
path.c perf tools: add test for strlcpy() 2010-08-21 11:22:47 -03:00
PERF-VERSION-GEN perf tools: Version incorrect with some versions of grep 2011-03-16 08:59:50 -03:00
probe-event.c perf probe: Fix multiple --vars options behavior 2011-04-05 15:36:04 -03:00
probe-event.h perf probe: Add filters support for available functions 2011-01-28 09:20:25 -02:00
probe-finder.c perf probe: Fix listing incorrect line number with inline function 2011-04-05 15:38:12 -03:00
probe-finder.h perf tools: Remove hardcoded include paths for elfutils 2010-11-19 16:38:04 -02:00
pstack.c perf newt: Make <- zoom out filters 2010-05-14 20:05:21 -03:00
pstack.h perf ui: Move hists browser to util/ui/browsers/ 2010-08-10 16:11:08 -03:00
python.c perf evlist: Fix per thread mmap setup 2011-05-15 10:02:14 -03:00
quote.c perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
quote.h perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
run-command.c perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
run-command.h perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
session.c perf session: Pass evsel in event_ops->sample() 2011-03-23 19:28:58 -03:00
session.h perf session: Pass evsel in event_ops->sample() 2011-03-23 19:28:58 -03:00
setup.py perf tools: Fix NO_NEWT=1 python build error 2011-03-29 16:46:57 -03:00
sigchain.c perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
sigchain.h perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
sort.c perf hist: Better displaying of unresolved DSOs and symbols 2010-12-06 15:12:34 -02:00
sort.h perf: Keep track of the max depth of a callchain 2010-08-22 20:43:17 +02:00
strbuf.c perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
strbuf.h perf tools: Remove some unused functions 2010-05-18 23:03:35 -03:00
strfilter.c perf: Fix missing strndup declaration 2011-03-04 01:17:18 +01:00
strfilter.h perf tools: Add strfilter for general purpose string filter 2011-01-28 09:19:38 -02:00
string.c Fix common misspellings 2011-03-31 11:26:23 -03:00
strlist.c perf probe: Fix --del to update current event list 2009-12-15 20:22:01 +01:00
strlist.h perf tools: Add for_each macros for strlist 2009-12-15 20:22:02 +01:00
svghelper.c perf timechart: Fix black idle boxes in the title 2011-02-28 08:56:14 +01:00
svghelper.h perf tools: Protect header files with a consistent style 2009-09-24 21:27:51 +02:00
symbol.c perf symbols: Properly align symbol_conf.priv_size 2011-03-29 14:18:39 -03:00
symbol.h perf symbol: Move sym_entry->skip to symbol->ignore 2011-03-11 13:36:01 -03:00
thread_map.c perf threads: Move thread_map to separate file 2011-01-24 10:59:00 -02:00
thread_map.h perf threads: Move thread_map to separate file 2011-01-24 10:59:00 -02:00
thread.c perf threads: Move thread_map to separate file 2011-01-24 10:59:00 -02:00
thread.h perf threads: Move thread_map to separate file 2011-01-24 10:59:00 -02:00
top.c perf top: Remove redundant syme->origin field 2011-03-11 13:28:45 -03:00
top.h perf symbol: Move sym_entry->skip to symbol->ignore 2011-03-11 13:36:01 -03:00
trace-event-info.c perf tools: Introduce event selectors 2011-01-03 16:39:04 -02:00
trace-event-parse.c perf script: Move printing of 'common' data from print_event and rename 2011-03-14 17:05:55 -03:00
trace-event-read.c perf: Use read() instead of lseek() in trace_event_read.c:skip() 2010-05-20 08:37:17 +02:00
trace-event-scripting.c perf session: Pass evsel in event_ops->sample() 2011-03-23 19:28:58 -03:00
trace-event.h perf session: Pass evsel in event_ops->sample() 2011-03-23 19:28:58 -03:00
types.h perf tools: Fix 64 bit integer format strings 2011-01-22 23:41:57 -02:00
usage.c perf top: Fall back to cpu-clock-tick hrtimer sampling if no cycle counter available 2009-06-07 17:31:52 +02:00
util.c perf util: Move do_read from session to util 2011-01-03 16:50:55 -02:00
util.h perf tools: Makefile: Remove platform-specific cruft 2011-02-18 07:42:07 -02:00
values.c perf tools: Fix 64 bit integer format strings 2011-01-22 23:41:57 -02:00
values.h perf tools: Protect header files with a consistent style 2009-09-24 21:27:51 +02:00
wrapper.c perf tools: remove xstrndup, xmalloc, xzalloc 2010-05-18 23:05:28 -03:00
xyarray.c perf tools: Introduce event selectors 2011-01-03 16:39:04 -02:00
xyarray.h perf tools: Introduce event selectors 2011-01-03 16:39:04 -02:00