[tip:perf/core] perf probe: Return errno when not hitting any event

[tip-bot for Kefeng Wang <tipbot@zytor.com>]

Commit-ID:  70946723eeb859466f026274b29c6196e39149c4
Gitweb:     http://git.kernel.org/tip/70946723eeb859466f026274b29c6196e39149c4
Author:     Kefeng Wang <wangkefeng.wang@huawei.com>
AuthorDate: Fri, 17 Mar 2017 16:16:32 +0800
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 21 Mar 2017 10:45:02 -0300

perf probe: Return errno when not hitting any event

On old perf, when using 'perf probe -d' to delete an inexistent event,
it returns errno, eg,

  -bash-4.3# perf probe -d xxx  || echo $?
  Info: Event "*:xxx" does not exist.
    Error: Failed to delete events.
  255

But now perf_del_probe_events() will always set ret = 0, different from
previous del_perf_probe_events(). After this, it returns errno again,
eg,

  -bash-4.3# ./perf probe -d xxx  || echo $?
  "xxx" does not hit any event.
    Error: Failed to delete events.
  254

And it is more appropriate to return -ENOENT instead of -EPERM.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: dddc7ee32fa1 ("perf probe: Fix an error when deleting probes successfully")
Link: http://lkml.kernel.org/r/1489738592-61011-1-git-send-email-wangkefeng.wang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-probe.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 1fcebc3..51cdc23 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -442,9 +442,9 @@ static int perf_del_probe_events(struct strfilter *filter)
 	}
 
 	if (ret == -ENOENT && ret2 == -ENOENT)
-		pr_debug("\"%s\" does not hit any event.\n", str);
-		/* Note that this is silently ignored */
-	ret = 0;
+		pr_warning("\"%s\" does not hit any event.\n", str);
+	else
+		ret = 0;
 
 error:
 	if (kfd >= 0)