perf probe: Show usage even if the last event is skipped
authorMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tue, 16 Jun 2015 11:50:57 +0000 (20:50 +0900)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Wed, 17 Jun 2015 19:31:42 +0000 (16:31 -0300)
commitd350bd571ffa89fc3bd07cfa9685d5210f459be8
tree50937fe4fc2dae8f7900dfa65b31555a9e40220a
parent5d618324dd4442d20dbdb039176787199ba2f12b
perf probe: Show usage even if the last event is skipped

When the last part of converted events are blacklisted or out-of-text,
those are skipped and perf probe doesn't show usage examples.  This
fixes it to show the example even if the last part of event list is
skipped.

E.g. without this patch, events are added, but suddenly end:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
    probe:vfs_open       (on vfs_*)
  ...
    probe:vfs_dentry_acceptable (on vfs_*)
    probe:vfs_load_quota_inode (on vfs_*)
  #

With this fix:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
  ...
    probe:vfs_load_quota_inode (on vfs_*)

  You can now use it in all perf tools, such as:

perf record -e probe:vfs_load_quota_inode -aR sleep 1

Note that this can be reproduced ONLY IF the vfs_caches_init* is the
last part of matched symbol list. I've checked this happens on
"3.19.0-generic #18-Ubuntu" kernel binary.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150616115057.19906.5502.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/util/probe-event.c