From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-Id: <20181030131502.089269375@goodmis.org> Date: Tue, 30 Oct 2018 09:13:33 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Linus Torvalds , Ingo Molnar , Andrew Morton , Tom Zanussi , Shuah Khan , Rajvi Jingar , stable@vger.kernel.org, Masami Hiramatsu Subject: [PATCH 1/2] tracing: Return -ENOENT if there is no target synthetic event References: <20181030131332.141023797@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Masami Hiramatsu Return -ENOENT error if there is no target synthetic event. This notices an operation failure to user as below; # echo 'wakeup_latency u64 lat; pid_t pid;' > synthetic_events # echo '!wakeup' >> synthetic_events sh: write error: No such file or directory Link: http://lkml.kernel.org/r/154013449986.25576.9487131386597290172.stgit@devbox Acked-by: Tom Zanussi Tested-by: Tom Zanussi Cc: Shuah Khan Cc: Rajvi Jingar Cc: stable@vger.kernel.org Fixes: 4b147936fa50 ('tracing: Add support for 'synthetic' events') Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events_hist.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index d239004aaf29..eb908ef2ecec 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1063,8 +1063,10 @@ static int create_synth_event(int argc, char **argv) event = NULL; ret = -EEXIST; goto out; - } else if (delete_event) + } else if (delete_event) { + ret = -ENOENT; goto out; + } if (argc < 2) { ret = -EINVAL; -- 2.19.0