linux_dsm_epyc7002/tools/perf
Jin Yao 8a99255a50 perf stat: Fix endless wait for child process
We hit a 'perf stat' issue by using following script:

  #!/bin/bash

  sleep 1000 &
  exec perf stat -a -e cycles -I1000 -- sleep 5

Since "perf stat" is launched by exec, the "sleep 1000" would be the
child process of "perf stat". The wait4() call will not return because
it's waiting for the child process "sleep 1000" to end. So 'perf stat'
doesn't return even after 5s passes.

This patch lets 'perf stat' return when the specified child process ends
(in this case, the specified child process is "sleep 5").

Committer testing:

  # cat test.sh
  #!/bin/bash

  sleep 10 &
  exec perf stat -a -e cycles -I1000 -- sleep 5
  #

Before:

  # time ./test.sh
  #           time             counts unit events
       1.001113090        108,453,351      cycles
       2.002062196        142,075,435      cycles
       3.002896194        164,801,068      cycles
       4.003731666        107,062,140      cycles
       5.002068867        112,241,832      cycles

  real	0m10.066s
  user	0m0.016s
  sys	0m0.101s
  #

After:

  # time ./test.sh
  #           time             counts unit events
       1.001016096         91,412,027      cycles
       2.002014963        124,063,708      cycles
       3.002883964        125,993,929      cycles
       4.003706470        120,465,734      cycles
       5.002006778        163,560,355      cycles

  real	0m5.123s
  user	0m0.014s
  sys	0m0.105s
  #

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1546501245-4512-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-03 12:12:18 -03:00
..
arch perf annotate: Introduce basic support for ARC 2018-12-17 14:59:42 -03:00
bench perf bench: Add epoll_ctl(2) benchmark 2018-11-21 22:39:55 -03:00
Documentation perf trace: Allow asking for not suppressing common string prefixes 2018-12-18 16:07:42 -03:00
examples/bpf perf augmented_raw_syscalls: Copy 'access' arg as well 2018-12-18 16:15:18 -03:00
include/bpf perf bpf: Move perf_event_output() from stdio.h to bpf.h 2018-12-18 12:23:58 -03:00
jvmti perf jvmti: Separate jvmti cmlr check 2018-11-21 22:39:58 -03:00
pmu-events perf vendor events intel: Fix Load_Miss_Real_Latency on SKL/SKX 2018-12-17 14:59:32 -03:00
python perf python: Make twatch.py work with both python2 and python3 2018-02-19 12:28:08 -03:00
scripts perf scripts python: exported-sql-viewer.py: Fix table find when table re-ordered 2018-11-05 14:53:00 -03:00
tests perf tests: Use shebangs in the shell scripts 2018-12-18 12:21:44 -03:00
trace perf trace beauty ioctl: Beautify USBDEVFS_ commands 2018-12-28 16:33:06 -03:00
ui perf ui helpline: Use strlcpy() as a shorter form of strncpy() + explicit set nul 2018-12-17 14:59:23 -03:00
util perf session: Add comment for perf_session__register_idle_thread() 2019-01-02 11:05:06 -03:00
.gitignore perf tools: Add trace/beauty/generated/ into .gitignore 2018-02-05 13:58:02 -03:00
Build perf trace: Remove audit-libs dependency if syscall tables are present 2018-01-23 09:51:38 -03:00
builtin-annotate.c perf tools: Remove perf_tool from event_op2 2018-09-19 10:25:10 -03:00
builtin-bench.c perf bench: Add epoll_ctl(2) benchmark 2018-11-21 22:39:55 -03:00
builtin-buildid-cache.c perf buildid-cache: Warn --purge-all failures 2018-05-15 10:32:16 -03:00
builtin-buildid-list.c Merge branch 'linus' into perf/core, to fix conflicts 2017-11-07 10:30:18 +01:00
builtin-c2c.c perf c2c: Increase the HITM ratio limit for displayed cachelines 2018-12-28 16:33:07 -03:00
builtin-config.c perf config: Show the configuration when no arguments are provided 2018-12-18 12:24:00 -03:00
builtin-data.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
builtin-diff.c perf hists: Clarify callchain disabling when available 2018-07-24 14:37:33 -03:00
builtin-evlist.c Merge branch 'linus' into perf/core, to fix conflicts 2017-11-07 10:30:18 +01:00
builtin-ftrace.c perf ftrace: Append an EOL when write tracing files 2018-02-19 09:49:12 -03:00
builtin-help.c perf help: Remove needless use of strncpy() 2018-12-17 14:59:18 -03:00
builtin-inject.c perf tools: Report itrace options in help 2018-09-19 15:06:59 -03:00
builtin-kallsyms.c perf machine: Ditch find_kernel_function variants 2018-04-30 12:20:54 -03:00
builtin-kmem.c tools lib traceevent, perf tools: Rename 'enum pevent_flag' to 'enum tep_flag' 2018-08-13 15:22:18 -03:00
builtin-kvm.c perf tools: Allow specifying proc-map-timeout in config file 2018-12-17 14:56:57 -03:00
builtin-list.c Merge branch 'linus' into perf/core, to fix conflicts 2017-11-07 10:30:18 +01:00
builtin-lock.c Merge branch 'linus' into perf/core, to fix conflicts 2017-11-07 10:30:18 +01:00
builtin-mem.c perf mem: Allow all record/report options 2018-04-18 15:35:48 -03:00
builtin-probe.c perf tools: No need to check if the argument to __get() function is NULL 2018-06-04 10:28:50 -03:00
builtin-record.c perf tools: Allow specifying proc-map-timeout in config file 2018-12-17 14:56:57 -03:00
builtin-report.c perf report: Display average IPC and IPC coverage per symbol 2018-12-17 14:55:44 -03:00
builtin-sched.c perf sched: Use sched->show_callchain where appropriate 2018-06-05 10:09:54 -03:00
builtin-script.c perf thread-stack: Fix thread stack processing for the idle task 2019-01-02 11:03:17 -03:00
builtin-stat.c perf stat: Fix endless wait for child process 2019-01-03 12:12:18 -03:00
builtin-timechart.c perf tools: Add missing open_memstream() prototype for systems lacking it 2018-12-18 12:23:57 -03:00
builtin-top.c perf top: Move perf_top__reset_sample_counters() to after counts display 2018-12-17 14:58:47 -03:00
builtin-trace.c perf trace beauty: Export function to get the files for a thread 2018-12-28 16:33:05 -03:00
builtin-version.c perf version: Print status for syscall_table 2018-04-12 10:33:34 -03:00
builtin.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
check-headers.sh tools headers uapi: Grab a copy of usbdevice_fs.h 2018-12-28 16:33:04 -03:00
command-list.txt perf help: Add missing subcommand version 2018-09-19 14:53:36 -03:00
CREDITS
design.txt
Makefile perf tools: Disable parallelism for 'make clean' 2018-08-20 08:54:58 -03:00
Makefile.config perf build: Don't unconditionally link the libbfd feature test to -liberty and -lz 2018-12-21 09:42:46 -03:00
Makefile.perf perf trace: Wire up ioctl's USBDEBFS_ cmd table generator 2018-12-28 16:33:05 -03:00
MANIFEST perf tools: Get all of tools/{arch,include}/ in the MANIFEST 2017-09-25 10:39:43 -03:00
perf-archive.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
perf-completion.sh perf tools: Auto-complete for events with ':' 2017-12-27 12:16:00 -03:00
perf-read-vdso.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
perf-sys.h Drop a bunch of metag references 2018-02-23 14:29:59 +00:00
perf-with-kcore.sh
perf.c perf tools: Remove dead quote.[ch] code 2018-06-04 10:28:50 -03:00
perf.h perf tools: Allow specifying proc-map-timeout in config file 2018-12-17 14:56:57 -03:00