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| author |   Namhyung Kim <namhyung@kernel.org> | 2017-06-18 23:22:59 +0900 |
|---|---|---|
| committer |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2017-06-19 22:05:51 -0300 |
| commit | e7bd9ba20a9ec7024a0566a93c22b9571a48939a (patch) | |
| tree | f8ebfa384d6525c69bf588b9ca41098f13e2eecc /tools/perf/builtin-ftrace.c | |
| parent | perf script: Support -F brstackoff,dso (diff) | |
| download | wireguard-linux-e7bd9ba20a9ec7024a0566a93c22b9571a48939a.tar.xz wireguard-linux-e7bd9ba20a9ec7024a0566a93c22b9571a48939a.zip | |
perf ftrace: Show error message when fails to set ftrace files
It'd be better for debugging to show an error message when it fails to
setup ftrace for some reason.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170618142302.25390-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-ftrace.c')
| -rw-r--r-- | tools/perf/builtin-ftrace.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c index 9e0b35cd0eea..966a94fa8200 100644 --- a/tools/perf/builtin-ftrace.c +++ b/tools/perf/builtin-ftrace.c @@ -61,6 +61,7 @@ static int __write_tracing_file(const char *name, const char *val, bool append) int fd, ret = -1; ssize_t size = strlen(val); int flags = O_WRONLY; + char errbuf[512]; file = get_tracing_file(name); if (!file) { @@ -75,14 +76,16 @@ static int __write_tracing_file(const char *name, const char *val, bool append) fd = open(file, flags); if (fd < 0) { - pr_debug("cannot open tracing file: %s\n", name); + pr_debug("cannot open tracing file: %s: %s\n", + name, str_error_r(errno, errbuf, sizeof(errbuf))); goto out; } if (write(fd, val, size) == size) ret = 0; else - pr_debug("write '%s' to tracing/%s failed\n", val, name); + pr_debug("write '%s' to tracing/%s failed: %s\n", + val, name, str_error_r(errno, errbuf, sizeof(errbuf))); close(fd); out: |