summaryrefslogtreecommitdiffstats
path: root/tools/perf/perf-with-kcore.sh
AgeCommit message (Collapse)Author
2014-09-17perf tools: Add perf-with-kcore scriptAdrian Hunter
Decoding an Intel PT trace of the kernel requires an accurate kernel object image. This is provided by making a copy of kcore. However the copy needs to be made under the same conditions as the original recording, and then it needs to be associated with the perf.data file. The perf-with-kcore script does that. The script also checks the permissions on the buildid cache and can be used to fix them. That is needed for distributions where root does not have a home directory and consequently writes to the same buildid cache as the user, resulting in cached files that the user does not have access to. Example: $ ./perf-with-kcore Usage: perf-with-kcore <perf sub-command> <perf.data directory> [<sub-command options> [ -- <workload>]] <perf sub-command> can be record, script, report or inject or: perf-with-kcore fix_buildid_cache_permissions $ ./perf-with-kcore record pt_uname -e intel_pt// -- uname Recording Using /home/ahunter/bin/perf perf version 3.15.rc3.g4549ba /home/ahunter/bin/perf record -o pt_uname/perf.data -e intel_pt// -- uname Linux [ perf record: Woken up 3 times to write data ] [ perf record: Captured and wrote 0.023 MB pt_uname/perf.data ] Copying kcore [sudo] password for ahunter: Done $ tools/perf/perf-with-kcore.sh script pt_uname | head Using /home/ahunter/bin/perf perf version 3.15.rc3.g4549ba /home/ahunter/bin/perf script -i pt_uname/perf.data --kallsyms=pt_uname/kcore_dir/kallsyms swapper 0 [002] 161533.969666: sched:sched_switch: swapper/2:0 [120] R ==> perf:11316 [120] :11315 11315 [003] 161533.969704: sched:sched_switch: perf:11315 [120] S ==> swapper/3:0 [120] :11316 11316 [002] 161533.969783: sched:sched_switch: perf:11316 [120] R ==> migration/2:33 [0] :33 33 [002] 161533.969791: sched:sched_switch: migration/2:33 [0] S ==> swapper/2:0 [120] swapper 0 [003] 161533.969792: sched:sched_switch: swapper/3:0 [120] R ==> perf:11316 [120] :11316 11316 [003] 161533.970062: branches: 0 [unknown] ([unknown]) => ffffffff810532fa native_write_msr_safe ([kernel.kallsyms]) :11316 11316 [003] 161533.970062: branches: ffffffff810532fd native_write_msr_safe ([kernel.kallsyms]) => ffffffff81035b31 pt_config_start ([kernel.kallsyms]) Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1406786474-9306-30-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>