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authorStephane Eranian <eranian@google.com>2014-12-17 16:23:55 +0100
committerArnaldo Carvalho de Melo <acme@redhat.com>2015-01-21 13:24:31 -0300
commit67121f85e464d66596f99afd8d188c1ae892f8fb (patch)
tree06dff15237cd0fa772f2c2e240e131058395fda4 /tools/perf/Documentation
parent25dd9171f51c482eb7c4dc8618766ae733756e2d (diff)
downloadlinux-next-67121f85e464d66596f99afd8d188c1ae892f8fb.tar.gz
perf mem: Enable sampling loads and stores simultaneously
This patch modifies perf mem to default to sampling loads and stores simultaneously. It could only do one or the other before yet there was no hardware restriction preventing simultaneous collection. With this patch, one run is sufficient to collect both. It is still possible to sample only loads or stores by using the -t option: $ perf mem -t load rec $ perf mem -t load rep Or $ perf mem -t store rec $ perf mem -t store rep The perf report TUI will show one event at a time. The store output will contain a Weight column which will be empty. In V2, we updated the man pages to reflect the change and also simplify the initialization of the argv vector passed to the cmd_*() functions as per LKML feedback. In V3, we fixed typos in the changelog. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Joe Mario <jmario@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Fowles <rfowles@redhat.com> Link: http://lkml.kernel.org/r/20141217152355.GA10053@thinkpad Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/Documentation')
-rw-r--r--tools/perf/Documentation/perf-mem.txt9
1 files changed, 5 insertions, 4 deletions
diff --git a/tools/perf/Documentation/perf-mem.txt b/tools/perf/Documentation/perf-mem.txt
index 1d78a4064da4..43310d8661fe 100644
--- a/tools/perf/Documentation/perf-mem.txt
+++ b/tools/perf/Documentation/perf-mem.txt
@@ -12,11 +12,12 @@ SYNOPSIS
DESCRIPTION
-----------
-"perf mem -t <TYPE> record" runs a command and gathers memory operation data
+"perf mem record" runs a command and gathers memory operation data
from it, into perf.data. Perf record options are accepted and are passed through.
-"perf mem -t <TYPE> report" displays the result. It invokes perf report with the
-right set of options to display a memory access profile.
+"perf mem report" displays the result. It invokes perf report with the
+right set of options to display a memory access profile. By default, loads
+and stores are sampled. Use the -t option to limit to loads or stores.
Note that on Intel systems the memory latency reported is the use-latency,
not the pure load (or store latency). Use latency includes any pipeline
@@ -29,7 +30,7 @@ OPTIONS
-t::
--type=::
- Select the memory operation type: load or store (default: load)
+ Select the memory operation type: load or store (default: load,store)
-D::
--dump-raw-samples=::