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2017-02-20perf record: Honor --quiet option properlyNamhyung Kim
It should call perf_quiet_option() to suppress messages. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20170217081742.17417-7-namhyung@kernel.org [ Fix merge clash with 483635a9d080 ("perf record: Add -a as default target") ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-20perf utils: Check verbose flag properlyNamhyung Kim
It now can have negative value to suppress the message entirely. So it needs to check it being positive. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20170217081742.17417-3-namhyung@kernel.org [ Adjust fuzz on tools/perf/util/pmu.c, add > 0 checks in many other places ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-17perf record: Add -a as default targetJiri Olsa
Running 'perf record' with no target (-a, -p, -t, etc) will now collect system wide data. Commiter notes: Testing it: [root@jouet ~]# perf record ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 1.351 MB perf.data (366 samples) ] # is equivalent to: # perf record -a ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 1.411 MB perf.data (978 samples) ] # Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20170217170018.GA15389@krava Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-14perf record: Do not put a variable sized type not at the end of a structArnaldo Carvalho de Melo
As this is a GNU extension and while harmless in this case, we can do the same thing in a more clearer way by using an existing thread_map constructor. With this we avoid this while compiling with clang: builtin-record.c:659:21: error: field 'map' with variable sized type 'struct thread_map' not at the end of a struct or class is a GNU extension [-Werror,-Wgnu-variable-sized-type-not-at-end] struct thread_map map; ^ 1 error generated. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-c9drclo52ezxmwa7qxklin2y@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-13perf evsel: Inform how to make a sysctl setting permanentArnaldo Carvalho de Melo
When a tool can't open counters due to the kernel.perf_event_paranoit sysctl setting, we inform how to tweak it to allow the operation to succeed, in addition to that, suggest setting /etc/sysctl.conf to make the setting permanent. Suggested-by: Ingo Molnar <mingo@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-4gwe99k4a6p12d4u8bbyttj2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-27perf tools: Propagate perf_config() errorsArnaldo Carvalho de Melo
Previously these were being ignored, sometimes silently. Stop doing that, emitting debug messages and handling the errors. Testing it: $ cat ~/.perfconfig cat: /home/acme/.perfconfig: No such file or directory $ perf stat -e cycles usleep 1 Performance counter stats for 'usleep 1': 938,996 cycles:u 0.003813731 seconds time elapsed $ perf top --stdio Error: You may not have permission to collect system-wide stats. Consider tweaking /proc/sys/kernel/perf_event_paranoid, <SNIP> [ perf record: Captured and wrote 0.019 MB perf.data (7 samples) ] [acme@jouet linux]$ perf report --stdio # To display the perf.data header info, please use --header/--header-only options. # Overhead Command Shared Object Symbol # ........ ....... ................. ......................... 71.77% usleep libc-2.24.so [.] _dl_addr 27.07% usleep ld-2.24.so [.] _dl_next_ld_env_entry 1.13% usleep [kernel.kallsyms] [k] page_fault $ $ touch ~/.perfconfig $ ls -la ~/.perfconfig -rw-rw-r--. 1 acme acme 0 Jan 27 12:14 /home/acme/.perfconfig $ $ perf stat -e instructions usleep 1 Performance counter stats for 'usleep 1': 244,610 instructions:u 0.000805383 seconds time elapsed $ [root@jouet ~]# chown acme.acme ~/.perfconfig [root@jouet ~]# perf stat -e cycles usleep 1 Warning: File /root/.perfconfig not owned by current user or root, ignoring it. Performance counter stats for 'usleep 1': 937,615 cycles 0.000836931 seconds time elapsed # Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-j2rq96so6xdqlr8p8rd6a3jx@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-11perf record: Add switch-output time option argumentJiri Olsa
It's now possible to specify the threshold time for perf.data like: $ perf record --switch-output=30s ... Once it's reached, the current data are dumped in to the perf.data.<timestamp> file and session does on. $ perf record --switch-output=30s ... [ perf record: dump data: Woken up 44 times ] [ perf record: Dump perf.data.2017010213043746 ] ... The time is expected to be a number with appended unit character - s/m/h/d. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1483955520-29063-7-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-11perf record: Add switch-output size warningJiri Olsa
Adding switch-output size warning if the requested size of lower than the wakeup ring buffer size. $ perf record --switch-output=1K ls WARNING: switch-output data size lower than wakeup kernel buffer size (258K) expect bigger perf.data sizes ... Signed-off-by: Jiri Olsa <jolsa@kernel.org> Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1483955520-29063-6-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-11perf record: Add switch-output size option argumentJiri Olsa
It's now possible to specify the threshold size for perf.data like: $ perf record --switch-output=2G ... Once it's reached, the current data are dumped in to the perf.data.<timestamp> file and session does on. $ perf record --switch-output=2G ... [ perf record: dump data: Woken up 7244 times ] [ perf record: Dump perf.data.2017010214093746 ] ... The size is expected to be a number with appended unit character - B/K/M/G. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1483955520-29063-5-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-11perf record: Change switch-output option to take optional argumentJiri Olsa
Next patches will add --switch-output option arguments, changing the option to allow that and adding its default value to 'signal'. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1483955520-29063-4-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-11perf record: Add struct switch_outputJiri Olsa
Next patches will add more --switch-output option arguments, so preparing the data holder. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1483955520-29063-3-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-03perf record: Fix --switch-output documentation and commentJiri Olsa
There's no --signal-trigger option, also adding the code comment into record man page. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Wang Nan <wangnan0@huawei.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1483431600-19887-4-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-03perf record: Make __record_options staticJiri Olsa
There's no need for this one to be global. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Wang Nan <wangnan0@huawei.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1483431600-19887-3-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-15perf record: Force ignore_missing_thread for uid optionJiri Olsa
Enable perf_evsel::ignore_missing_thread for -u option to ignore complete failure if any of the user's processes die between its enumeration and time we open the event. Committer notes: While doing a 'make -j4 allmodconfig' we sometimes get into the race: Before: # perf record -u acme Error: The sys_perf_event_open() syscall returned with 3 (No such process) for event (cycles:ppp). /bin/dmesg may provide additional information. No CONFIG_PERF_EVENTS=y kernel support configured? # After: [root@jouet ~]# perf record -u acme WARNING: Ignored open failure for pid 9888 WARNING: Ignored open failure for pid 18059 [root@jouet ~]# Which is an improvement, with the races not preventing the remaining threads for the specified user from being monitored, but the message probably needs further clarification. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1481538943-21874-6-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-11-29perf tools: Introduce perf hooksWang Nan
Perf hooks allow hooking user code at perf events. They can be used for manipulation of BPF maps, taking snapshot and reporting results. In this patch two perf hook points are introduced: record_start and record_end. To avoid buggy user actions, a SIGSEGV signal handler is introduced into 'perf record'. It turns off perf hook if it causes a segfault and report an error to help debugging. A test case for perf hook is introduced. Test result: $ ./buildperf/perf test -v hook 50: Test perf hooks : --- start --- test child forked, pid 10311 SIGSEGV is observed as expected, try to recover. Fatal error (SEGFAULT) in perf hook 'test' test child finished with 0 ---- end ---- Test perf hooks: Ok Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Joe Stringer <joe@ovn.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/20161126070354.141764-5-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-29perf record: Add support for using symbols in address filtersAdrian Hunter
Symbols come from either the DSO or /proc/kallsyms for the kernel. Details of the functionality can be found in Documentation/perf-record.txt. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Link: http://lkml.kernel.org/r/1474641528-18776-8-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-29perf record: Fix error pathsAdrian Hunter
Some error paths do not tidy-up. Fix that. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Link: http://lkml.kernel.org/r/1474641528-18776-6-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-29perf record: Rename label 'out_symbol_exit'Adrian Hunter
In preparation for fixing the error paths, rename label 'out_symbol_exit' to be 'out' because that error path can be used irrespective of whether symbols (or anything else) has been initialized. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Link: http://lkml.kernel.org/r/1474641528-18776-5-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-22perf tools: Add PMU configuration to toolsMathieu Poirier
Now that the required mechanic is there to deal with PMU specific configuration, add the functionality to the tools where events can be selected. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1474041004-13956-7-git-send-email-mathieu.poirier@linaro.org [ Fix the build on XSI-compliant systems, using str_error_r() to make sure we return a string, not an integer ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-23perf record: Fix spelling mistake "Finshed" -> "Finished"Colin Ian King
Trivial fix to spelling mistake in pr_debug message. Signed-off-by: Colin King <colin.king@canonical.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20160822183008.26368-1-colin.king@canonical.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-23perf record: Use USEC_PER_MSECArnaldo Carvalho de Melo
Instead of a naked 1000. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-7v6be7jhvstbkvk3rsytjw0o@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-02perf record: Add --sample-cpu optionJiri Olsa
Adding --sample-cpu option to be able to explicitly enable CPU sample type. Currently it's only enable implicitly in case the target is cpu related. It will be useful for following c2c record tool. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1470074555-24889-8-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-15perf record: Add --tail-synthesize optionWang Nan
When working with overwritable ring buffer there's a inconvenience problem: if perf dumps data after a long period after it starts, non-sample events may lost, which makes following 'perf report' unable to identify proc name and mmap layout. For example: # perf record -m 4 -e raw_syscalls:* -g --overwrite --switch-output \ dd if=/dev/zero of=/dev/null send SIGUSR2 after dd runs long enough. The resuling perf.data lost correct comm and mmap events: # perf script -i perf.data.2016061522374354 perf 24478 [004] 2581325.601789: raw_syscalls:sys_exit: NR 0 = 512 ^^^^ Should be 'dd' 27b2e8 syscall_slow_exit_work+0xfe2000e3 (/lib/modules/4.6.0-rc3+/build/vmlinux) 203cc7 do_syscall_64+0xfe200117 (/lib/modules/4.6.0-rc3+/build/vmlinux) b18d83 return_from_SYSCALL_64+0xfe200000 (/lib/modules/4.6.0-rc3+/build/vmlinux) 7f47c417edf0 [unknown] ([unknown]) ^^^^^^^^^^^^ Fail to unwind This patch provides a '--tail-synthesize' option, allows perf to collect system status when finalizing output file. In resuling output file, the non-sample events reflect system status when dumping data. After this patch: # perf record -m 4 -e raw_syscalls:* -g --overwrite --switch-output --tail-synthesize \ dd if=/dev/zero of=/dev/null # perf script -i perf.data.2016061600544998 dd 27364 [004] 2583244.994464: raw_syscalls:sys_enter: NR 1 (1, ... ^^ Correct comm 203a18 syscall_trace_enter_phase2+0xfe2001a8 ([kernel.kallsyms]) 203aa5 syscall_trace_enter+0xfe200055 ([kernel.kallsyms]) 203caa do_syscall_64+0xfe2000fa ([kernel.kallsyms]) b18d83 return_from_SYSCALL_64+0xfe200000 ([kernel.kallsyms]) d8e50 __GI___libc_write+0xffff01d9639f4010 (/tmp/oxygen_root-w00229757/lib64/libc-2.18.so) ^^^^^ Correct unwind This option doesn't aim to solve this problem completely. If a process terminates before SIGUSR2, we still lost its COMM and MMAP events. For example, we can't unwind correctly from the final perf.data we get from the previous example, because when perf collects the final output file (when we press C-c), 'dd' has been terminated so its '/proc/<pid>/mmap' becomes empty. However, this is a cheaper choice. To completely solve this problem we need to continously output non-sample events. To satisify the requirement of daemonization, we need to merge them periodically. It is possible but requires much more code and cycles. Automatically select --tail-synthesize when --overwrite is provided. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1468485287-33422-16-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-15perf tools: Enable overwrite settingsWang Nan
This patch allows following config terms and option: Globally setting events to overwrite; # perf record --overwrite ... Set specific events to be overwrite or no-overwrite. # perf record --event cycles/overwrite/ ... # perf record --event cycles/no-overwrite/ ... Add missing config terms and update the config term array size because the longest string length has changed. For overwritable events, it automatically selects attr.write_backward since perf requires it to be backward for reading. Test result: # perf record --overwrite -e syscalls:*enter_nanosleep* usleep 1 [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.011 MB perf.data (1 samples) ] # perf evlist -v syscalls:sys_enter_nanosleep: type: 2, size: 112, config: 0x134, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, write_backward: 1 # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1468485287-33422-14-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-15perf record: Read from overwritable ring bufferWang Nan
Drive the evlist->bkw_mmap_state state machine during draining and when SIGUSR2 is received. Read the backward ring buffer in record__mmap_read_all. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1468485287-33422-12-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-15perf evlist: Setup backward mmap state machineWang Nan
Introduce a bkw_mmap_state state machine to evlist: .________________(forbid)_____________. | V NOTREADY --(0)--> RUNNING --(1)--> DATA_PENDING --(2)--> EMPTY ^ ^ | ^ | | |__(forbid)____/ |___(forbid)___/| | | \_________________(3)_______________/ NOTREADY : Backward ring buffers are not ready RUNNING : Backward ring buffers are recording DATA_PENDING : We are required to collect data from backward ring buffers EMPTY : We have collected data from backward ring buffers. (0): Setup backward ring buffer (1): Pause ring buffers for reading (2): Read from ring buffers (3): Resume ring buffers for recording We can't avoid this complexity. Since we deliberately drop records from overwritable ring buffer, there's no way for us to check remaining from ring buffer itself (by checking head and old pointers). Therefore, we need DATA_PENDING and EMPTY state to help us recording what we have done to the ring buffer. In record__mmap_read_evlist(), drive this state machine from DATA_PENDING to EMPTY. In perf_evlist__mmap_per_evsel(), drive this state machine from NOTREADY to RUNNING when creating backward mmap. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: He Kuang <hekuang@huawei.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1468485287-33422-11-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-15perf evlist: Introduce backward_mmap array for evlistWang Nan
Add backward_mmap to evlist, free it together with normal mmap. Improve perf_evlist__pick_pc(), search backward_mmap if evlist->mmap is not available. This patch doesn't alloc this array. It will be allocated conditionally in the following commits. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: He Kuang <hekuang@huawei.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1468485287-33422-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-15perf record: Decouple record__mmap_read() and evlist.Wang Nan
Perf evlist will have multiple mmap arrays. Update record__mmap_read(): it should read from 'struct perf_mmap' directly. Also, make record__mmap_read() ready to read from backward ring buffer. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: He Kuang <hekuang@huawei.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1468485287-33422-5-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-12tools: Introduce str_error_r()Arnaldo Carvalho de Melo
The tools so far have been using the strerror_r() GNU variant, that returns a string, be it the buffer passed or something else. But that, besides being tricky in cases where we expect that the function using strerror_r() returns the error formatted in a provided buffer (we have to check if it returned something else and copy that instead), breaks the build on systems not using glibc, like Alpine Linux, where musl libc is used. So, introduce yet another wrapper, str_error_r(), that has the GNU interface, but uses the portable XSI variant of strerror_r(), so that users rest asured that the provided buffer is used and it is what is returned. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-28perf record: Prepare picking perf_event_mmap_page from multiple evlistsWang Nan
Following commits introduce new evlists to record. This patch adjusts record__pick_pc() and introduces perf_evlist__pick_pc() to read control page from one specific evlist. record__pick_pc() will be improved to search control page from multiple evlists. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1467023052-146749-4-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-28perf record: Prepare reading from multiple evlists in record__mmap_read_all()Wang Nan
Following commits introduce new evlists to record. This patch adjusts record__mmap_read_all() and record__mmap_read(): converting original record__mmap_read_all() to record__mmap_read_evlist(), read from one evlist; makes record__mmap_read() reading from specific evlist. record__mmap_read_all() will be improved to read from multiple evlists. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1467023052-146749-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-28perf record: Move mmap setup block to separate functionWang Nan
Following commits introduce multiple evlists to record. This patch extracts perf_evlist__mmap_ex() processing to a new function, creates record__mmap() and record__mmap_evlist() to wrap perf_evlist__mmap_ex() and its error processing. They will be improvemented to create mmap for all evlists. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1467023052-146749-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-23perf evlist: Rename for_each() macros to for_each_entry()Arnaldo Carvalho de Melo
To match the semantics for list.h in the kernel, that are used to implement those macros. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Taeung Song <treeze.taeung@gmail.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-qbcjlgj0ffxquxscahbpddi3@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-23perf config: Move config declarations from util/cache.h to util/config.hTaeung Song
Lately util/config.h has been added but util/cache.h has declarations of functions and a global variable for config features. To manage codes about configuration at one spot, move them to util/config.h and let source files that need config features include config.h And if the source files that included previous cache.h need only config.h, remove including cache.h. Signed-off-by: Taeung Song <treeze.taeung@gmail.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1466672119-4852-2-git-send-email-treeze.taeung@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-21perf record: Add --dry-run option to check cmdline optionsWang Nan
With '--dry-run', 'perf record' doesn't do reall recording. Combine with llvm.dump-obj option, --dry-run can be used to help compile BPF objects for embedded platform. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1466064161-48553-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-30perf record: Robustify perf_event__synth_time_conv()Wang Nan
It is possible that all events in an evlist are overwritable. perf_event__synth_time_conv() should not crash in this case. record__pick_pc() is used to check avaliability. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1464056944-166978-3-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> [ Split from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-23perf record: Read from backward ring bufferWang Nan
Introduce rb_find_range() to find start and end position from a backward ring buffer. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1463987628-163563-5-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-23perf record: Rename variable to make code clearWang Nan
record__mmap_read() writes data from ring buffer into perf.data. 'head' is maintained by the kernel, points to the last written record. 'old' is maintained by perf, points to the record read in previous round. record__mmap_read() saves data from 'old' to 'head' to perf.data. The names of these variables are not very intutive. In addition, when dealing with backward writing ring buffer, the md->prev pointer should point to 'head' instead of the last byte it got. Add 'start' and 'end' pointer to make code clear and set md->prev to 'head' instead of the moved 'old' pointer. This patch doesn't change behavior since: buf = &data[old & md->mask]; size = head - old; old += size; <--- Here, old == head Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1463987628-163563-4-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-23perf record: Prevent reading invalid data in record__mmap_readWang Nan
When record__mmap_read() requires data more than the size of ring buffer, drop those data to avoid accessing invalid memory. This can happen when reading from overwritable ring buffer, which should be avoided. However, check this for robustness. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1463987628-163563-3-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-28perf record: Generate tracking events for process forked by perfWang Nan
With 'perf record --switch-output' without -a, record__synthesize() in record__switch_output() won't generate tracking events because there's no thread_map in evlist. Which causes newly created perf.data doesn't contain map and comm information. This patch creates a fake thread_map and directly call perf_event__synthesize_thread_map() for those events. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1461178794-40467-8-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-28perf record: Disable buildid cache options by default in switch output modeWang Nan
The cost of buildid cache processing is high: reading all events in output perf.data, opening each elf file to read buildids then copying them into ~/.debug directory. In switch output mode, these heavy works block perf from receiving perf events for too long. Enable no-buildid and no-buildid-cache by default if --switch-output is provided. Still allow user use --no-no-buildid to explicitly enable buildid in this case. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1461178794-40467-6-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> [ Updated man page ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-28perf record: Force enable --timestamp-filename when --switch-output is providedWang Nan
Without this patch, the last output doesn't have timestamp appended if --timestamp-filename is not explicitly provided. For example: # perf record -a --switch-output & [1] 11224 # kill -s SIGUSR2 11224 [ perf record: dump data: Woken up 1 times ] # [ perf record: Dump perf.data.2015122622372823 ] # fg perf record -a --switch-output ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.027 MB perf.data (540 samples) ] # ls -l total 836 -rw------- 1 root root 33256 Dec 26 22:37 perf.data <---- *Odd* -rw------- 1 root root 817156 Dec 26 22:37 perf.data.2015122622372823 Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1461178794-40467-5-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> [ Updated man page, that also got an entry for --timestamp-filename ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-28perf record: Split output into multiple files via '--switch-output'Wang Nan
Allow 'perf record' to split its output into multiple files. For example: # ~/perf record -a --timestamp-filename --switch-output & [1] 10763 # kill -s SIGUSR2 10763 [ perf record: dump data: Woken up 1 times ] # [ perf record: Dump perf.data.2015122622314468 ] # kill -s SIGUSR2 10763 [ perf record: dump data: Woken up 1 times ] # [ perf record: Dump perf.data.2015122622314762 ] # kill -s SIGUSR2 10763 [ perf record: dump data: Woken up 1 times ] #[ perf record: Dump perf.data.2015122622315171 ] # fg perf record -a --timestamp-filename --switch-output ^C[ perf record: Woken up 1 times to write data ] [ perf record: Dump perf.data.2015122622315513 ] [ perf record: Captured and wrote 0.014 MB perf.data.<timestamp> (296 samples) ] # ls -l total 920 -rw------- 1 root root 797692 Dec 26 22:31 perf.data.2015122622314468 -rw------- 1 root root 59960 Dec 26 22:31 perf.data.2015122622314762 -rw------- 1 root root 59912 Dec 26 22:31 perf.data.2015122622315171 -rw------- 1 root root 19220 Dec 26 22:31 perf.data.2015122622315513 Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1461178794-40467-4-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> [ Added man page entry, used the re-synthesize patch in this series as a fixup ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-28perf tools: Derive trigger class from auxtrace_snapshotWang Nan
auxtrace_snapshot_state matches the trigger model. Use trigger to implement it. auxtrace_snapshot_state and auxtrace_snapshot_err are absorbed. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1461178794-40467-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-18perf tools: Ditch record_opts.callgraph_setArnaldo Carvalho de Melo
We have callchain_param.enabled for that. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-silwqjc2t25ls42dsvg28pp5@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-15perf record: Export record_opts based callchain parsing helperArnaldo Carvalho de Melo
To be able to call it outside option parsing, like when setting a default --call-graph parameter in 'perf trace' when just --min-stack is used. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-xay69plylwibpb3l4isrpl1k@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-14perf record: Add '--timestamp-filename' option to append timestamp to output ↵Wang Nan
file name This option appends current timestamp to the output file name. For example: # perf record -a --timestamp-filename ^C[ perf record: Woken up 1 times to write data ] [ perf record: Dump perf.data.2015122622265847 ] [ perf record: Captured and wrote 0.742 MB perf.data.<timestamp> (90 samples) ] # ls perf.data.201512262226584 The timestamp will be useful for identifying each perf.data after the 'perf record' support for generating multiple output files gets introduced. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1460535673-159866-5-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-14perf record: Turns auxtrace_snapshot_enable into 3 statesWang Nan
auxtrace_snapshot_enable has only two states (0/1). Turns it into a triple states enum so SIGUSR2 handler can safely do other works without triggering auxtrace snapshot. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1460535673-159866-4-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang <hekuang@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-11perf evsel: Do not use globals in config()Arnaldo Carvalho de Melo
Instead receive a callchain_param pointer to configure callchain aspects, not doing so if NULL is passed. This will allow fine grained control over which evsels in an evlist gets callchains enabled. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-2mupip6khc92mh5x4nw9to82@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-11perf bpf: Clone bpf stdout events in multiple bpf scriptsWang Nan
This patch allows cloning bpf-output event configuration among multiple bpf scripts. If there exist a map named '__bpf_output__' and not configured using 'map:__bpf_output__.event=', this patch clones the configuration of another '__bpf_stdout__' map. For example, following command: # perf trace --ev bpf-output/no-inherit,name=evt/ \ --ev ./test_bpf_trace.c/map:__bpf_stdout__.event=evt/ \ --ev ./test_bpf_trace2.c usleep 100000 equals to: # perf trace --ev bpf-output/no-inherit,name=evt/ \ --ev ./test_bpf_trace.c/map:__bpf_stdout__.event=evt/ \ --ev ./test_bpf_trace2.c/map:__bpf_stdout__.event=evt/ \ usleep 100000 Signed-off-by: Wang Nan <wangnan0@huawei.com> Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1460128045-97310-4-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>