perf report/annotate/script: Add option to specify a CPU range
authorAnton Blanchard <anton@samba.org>
Mon, 4 Jul 2011 11:57:50 +0000 (21:57 +1000)
committerIngo Molnar <mingo@elte.hu>
Tue, 5 Jul 2011 08:44:44 +0000 (10:44 +0200)
commit5d67be97f8903d05ce53597fb5f3bc25a45e8026
tree5ce8c2407d50570d7fee79b9c7f24e8eb89384b4
parent9f8b6a6cf0ee78de87ebe1e87f54bec1c1741ef7
perf report/annotate/script: Add option to specify a CPU range

Add an option to perf report/annotate/script to specify which
CPUs to operate on. This enables us to take a single system wide
profile and analyse each CPU (or group of CPUs) in isolation.

This was useful when profiling a multiprocess workload where the
bottleneck was on one CPU but this was hidden in the overall
profile. Per process and per thread breakdowns didn't help
because multiple processes were running on each CPU and no
single process consumed an entire CPU.

The patch converts the list of CPUs returned by cpu_map__new
into a bitmap for fast lookup. I wanted to use -C to be
consistent with perf top/record/stat, but unfortunately perf
report already uses -C <comms>.

 v2: Incorporate suggestions from David Ahern:
- Added -c to perf script
- Check that SAMPLE_CPU is set when -c is used
- Update documentation

 v3: Create perf_session__cpu_bitmap()

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Link: http://lkml.kernel.org/r/20110704215750.11647eb9@kryten
Signed-off-by: Ingo Molnar <mingo@elte.hu>
tools/perf/Documentation/perf-annotate.txt
tools/perf/Documentation/perf-report.txt
tools/perf/Documentation/perf-script.txt
tools/perf/builtin-annotate.c
tools/perf/builtin-report.c
tools/perf/builtin-script.c
tools/perf/util/session.c
tools/perf/util/session.h