perf evlist: Add API to pause/resume
authorWang Nan <wangnan0@huawei.com>
Mon, 23 May 2016 07:13:38 +0000 (07:13 +0000)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Mon, 23 May 2016 21:22:00 +0000 (18:22 -0300)
commit65aea2338765da1a58cc26eeb84d72308492ecb5
tree90998c4711d3349fbe05bc15ac60ece597c92f3c
parent12f3ca4fc8e27aa602c9c3c717d755b1e8f7fd47
perf evlist: Add API to pause/resume

perf_evlist__toggle_{pause,resume}() are introduced to pause/resume
events in an evlist. Utilize PERF_EVENT_IOC_PAUSE_OUTPUT ioctl.

Following commits use them to ensure overwrite ring buffer is paused
before reading.

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/1463987628-163563-2-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
[ Return -1, like all other ioctl() usage in evlist.c, rename 'pause'
  arg to avoid breaking the build on ubuntu 12.04 and other old systems ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/util/evlist.c
tools/perf/util/evlist.h