perf probe: Fix list result when address is zero
authorWang Nan <wangnan0@huawei.com>
Wed, 26 Aug 2015 10:57:43 +0000 (10:57 +0000)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Wed, 26 Aug 2015 13:39:20 +0000 (10:39 -0300)
commitbe07afe92a09638db9159d2c0794487d66a437a2
tree3c8318782b4cb90ae0629e39f050d2c430540f61
parent614e2fdbd79b47ddf63a1ccd3f2343e98c3077fb
perf probe: Fix list result when address is zero

When manually added uprobe point with zero address, 'perf probe -l'
reports error. For example:

  # echo p:probe_libc/abs_0 /path/to/lib.bin:0x0 arg1=%ax > \
           /sys/kernel/debug/tracing/uprobe_events

  # perf probe -l
  Error: Failed to show event list.

Probing at 0x0 is possible and useful when lib.bin is not a normal
shared object but is manually mapped. However, in this case kernel
report:

  # cat /sys/kernel/debug/tracing/uprobe_events
  p:probe_libc/abs_0 /path/to/lib.bin:0x          (null) arg1=%ax

This patch supports the above kernel output.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/util/probe-event.c