diff options
| author | Steven Rostedt (Red Hat) <rostedt@goodmis.org> | 2013-07-01 23:58:24 +0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2013-07-02 04:34:28 +0400 |
| commit | 10246fa35d4ffdfe472185d4cbf9c2dfd9a9f023 (patch) | |
| tree | 277cb4041486bfe87730fd767b2a8072330211b9 /kernel/trace/trace_irqsoff.c | |
| parent | b04d52e368e2cf526abb2bab61f304eaea126af2 (diff) | |
| download | linux-10246fa35d4ffdfe472185d4cbf9c2dfd9a9f023.tar.xz | |
tracing: Use flag buffer_disabled for irqsoff tracer
If the ring buffer is disabled and the irqsoff tracer records a trace it
will clear out its buffer and lose the data it had previously recorded.
Currently there's a callback when writing to the tracing_of file, but if
tracing is disabled via the function tracer trigger, it will not inform
the irqsoff tracer to stop recording.
By using the "mirror" flag (buffer_disabled) in the trace_array, that keeps
track of the status of the trace_array's buffer, it gives the irqsoff
tracer a fast way to know if it should record a new trace or not.
The flag may be a little behind the real state of the buffer, but it
should not affect the trace too much. It's more important for the irqsoff
tracer to be fast.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_irqsoff.c')
| -rw-r--r-- | kernel/trace/trace_irqsoff.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index b19d065a28cb..2aefbee93a6d 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -373,7 +373,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip) struct trace_array_cpu *data; unsigned long flags; - if (likely(!tracer_enabled)) + if (!tracer_enabled || !tracing_is_enabled()) return; cpu = raw_smp_processor_id(); @@ -416,7 +416,7 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip) else return; - if (!tracer_enabled) + if (!tracer_enabled || !tracing_is_enabled()) return; data = per_cpu_ptr(tr->trace_buffer.data, cpu); |