perf evsel: Create events initially disabled -- again

764e16a3 changed perf-record to create events disabled by default and
enable them once perf initializations are done. This setting was dropped
by 0f82ebc4

. Now perf events are once again generated during perf's
initialization phase (e.g., generating maps).

As an example, perf opens a lot of files at startup. Unpatched:

perf record -e syscalls:sys_enter_open -ga -fo /tmp/perf.data -- sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.087 MB /tmp/perf.data (~3798 samples) ]

Using perf-script to look at the samples shows the perf command generating
563 of the 566 total events.

Patched:

perf record -e syscalls:sys_enter_open -ga -fo /tmp/perf.data -- sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.028 MB /tmp/perf.data (~1206 samples) ]

Using perf-script to look at the samples does not show perf command.

Signed-off-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1336968088-11531-1-git-send-email-dsahern@gmail.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>