diff options
| author | Frederic Weisbecker <fweisbec@gmail.com> | 2009-03-16 00:32:41 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-03-16 09:13:18 +0100 |
| commit | ac1d52d0b85854958c7e78c8006e39aadb6ce4b8 (patch) | |
| tree | fc50818980e376a66d44f991b94e8a52c03e68fc /kernel/trace | |
| parent | 59f586db98919d7d9c43527b26c8de1cdf9ed912 (diff) | |
tracing/ftrace: fix double calls to tracing_start()
Impact: fix a warning during preemptirqsoff selftests
When the preemptirqsoff selftest fails, we see the following
warning:
[ 6.050000] Testing tracer preemptirqsoff: .. no entries found ..
------------[ cut here ]------------
[ 6.060000] WARNING: at kernel/trace/trace.c:688 tracing_start+0x67/0xd3()
[ 6.060000] Modules linked in:
[ 6.060000] Pid: 1, comm: swapper Tainted: G
[ 6.060000] Call Trace:
[ 6.060000] [<ffffffff802460ff>] warn_slowpath+0xb1/0x100
[ 6.060000] [<ffffffff802a8f5b>] ? trace_preempt_on+0x35/0x4b
[ 6.060000] [<ffffffff802a37fb>] ? tracing_start+0x31/0xd3
[ 6.060000] [<ffffffff802a37fb>] ? tracing_start+0x31/0xd3
[ 6.060000] [<ffffffff80271e0b>] ? __lock_acquired+0xe6/0x1f2
[ 6.060000] [<ffffffff802a37fb>] ? tracing_start+0x31/0xd3
[ 6.060000] [<ffffffff802a3831>] tracing_start+0x67/0xd3
[ 6.060000] [<ffffffff802a8ace>] ? irqsoff_tracer_reset+0x2d/0x57
[ 6.060000] [<ffffffff802a4d1c>] trace_selftest_startup_preemptirqsoff+0x1c8/0x1f1
[ 6.060000] [<ffffffff802a4798>] register_tracer+0x12f/0x241
[ 6.060000] [<ffffffff810250d0>] ? init_irqsoff_tracer+0x0/0x53
[ 6.060000] [<ffffffff8102510b>] init_irqsoff_tracer+0x3b/0x53
This is because in fail case, the preemptirqsoff tracer selftest calls twice
the tracing_start() function:
int
trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr)
{
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
ret = -1;
tracing_start(); <-----
goto out;
}
[...]
out:
trace->reset(tr);
tracing_start(); <------
tracing_max_latency = save_max;
return ret;
}
Since it is well handled in the out path, we don't need the conditional one.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1237159961-7447-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace_selftest.c | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index f907a2b29028..a2ca6f0fef9b 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -414,7 +414,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * ret = tracer_init(trace, tr); if (ret) { warn_failed_init_tracer(trace, ret); - goto out; + goto out_no_start; } /* reset the max latency */ @@ -432,21 +432,16 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * tracing_stop(); /* check both trace buffers */ ret = trace_test_buffer(tr, NULL); - if (ret) { - tracing_start(); + if (ret) goto out; - } ret = trace_test_buffer(&max_tr, &count); - if (ret) { - tracing_start(); + if (ret) goto out; - } if (!ret && !count) { printk(KERN_CONT ".. no entries found .."); ret = -1; - tracing_start(); goto out; } @@ -475,9 +470,10 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * goto out; } - out: - trace->reset(tr); +out: tracing_start(); +out_no_start: + trace->reset(tr); tracing_max_latency = save_max; return ret; |