From: Yann Droneaud <ydroneaud@opteya.com>
To: linux-kernel@vger.kernel.org
Subject: [PATCH v2 2/2] perf tools: report PERF_FLAG_FD_CLOEXEC probing error once
Date: Thu, 1 Oct 2015 17:18:57 +0200 [thread overview]
Message-ID: <50528203b94e72fc2aa7d4e9130523a09169c00c.1443708092.git.ydroneaud@opteya.com> (raw)
In-Reply-To: <cover.1443708092.git.ydroneaud@opteya.com>
In-Reply-To: <cover.1443708092.git.ydroneaud@opteya.com>
In case of failure, unrelated to PERF_FLAG_FD_CLOEXEC,
perf_flag_probe() reports the error twice. For example:
$ perf record ls
Error:
perf_event_open(..., PERF_FLAG_FD_CLOEXEC) failed with unexpected error 16 (Device or resource busy)
perf_event_open(..., 0) failed unexpectedly with error 16 (Device or resource busy)
There's no need for the second error message, so this
patch changes the function to only report a second
error message when the two calls to perf_even_open(2)
fail with different error codes.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: William Cohen <wcohen@redhat.com>
Link: http://lkml.kernel.org/r/cover.1443708092.git.ydroneaud@opteya.com
Reported-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
---
tools/perf/util/cloexec.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)
diff --git a/tools/perf/util/cloexec.c b/tools/perf/util/cloexec.c
index be226d293c91..552528698566 100644
--- a/tools/perf/util/cloexec.c
+++ b/tools/perf/util/cloexec.c
@@ -26,7 +26,7 @@ static int perf_flag_probe(void)
.exclude_kernel = 1,
};
int fd;
- int err;
+ int err0, err1;
int cpu;
pid_t pid = -1;
char sbuf[STRERR_BUFSIZE];
@@ -49,7 +49,7 @@ static int perf_flag_probe(void)
}
break;
}
- err = errno;
+ err0 = errno;
if (fd >= 0) {
close(fd);
@@ -57,12 +57,12 @@ static int perf_flag_probe(void)
}
/* ignore busy errors */
- if (err == EBUSY)
+ if (err0 == EBUSY)
return -1;
- WARN_ONCE(err != EINVAL,
+ WARN_ONCE(err0 != EINVAL,
"perf_event_open(..., PERF_FLAG_FD_CLOEXEC) failed with unexpected error %d (%s)\n",
- err, strerror_r(err, sbuf, sizeof(sbuf)));
+ err0, strerror_r(err0, sbuf, sizeof(sbuf)));
/* not supported, confirm error related to PERF_FLAG_FD_CLOEXEC */
while (1) {
@@ -73,17 +73,18 @@ static int perf_flag_probe(void)
}
break;
}
- err = errno;
+ err1 = errno;
- if (fd >= 0)
+ if (fd >= 0) {
close(fd);
+ return 0;
+ }
- if (WARN_ONCE(fd < 0,
- "perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n",
- err, strerror_r(err, sbuf, sizeof(sbuf))))
- return -1;
+ WARN_ONCE(err0 != err1,
+ "perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n",
+ err1, strerror_r(err1, sbuf, sizeof(sbuf)));
- return 0;
+ return -1;
}
unsigned long perf_event_open_cloexec_flag(void)
--
2.4.3
next prev parent reply other threads:[~2015-10-01 15:19 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-01 15:16 [PATCH v2 0/2] perf tool: improve error handling in perf_flag_probe() Yann Droneaud
2015-10-01 15:18 ` [PATCH v2 1/2] perf tools: shortcut PERF_FLAG_FD_CLOEXEC probing in case of EBUSY error Yann Droneaud
[not found] ` <20151001205247.GA4445@krava.redhat.com>
2015-10-01 21:32 ` Yann Droneaud
2015-10-02 13:19 ` Jiri Olsa
2015-10-01 15:18 ` Yann Droneaud [this message]
[not found] ` <20151002132041.GB1673@krava.brq.redhat.com>
2015-10-02 13:43 ` [PATCH v2 2/2] perf tools: report PERF_FLAG_FD_CLOEXEC probing error once Yann Droneaud
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