diff options
| author | Bo Yan <byan@nvidia.com> | 2017-09-18 10:03:35 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-05 09:43:59 +0200 |
| commit | 5fb4be27dac5f0ad925604acf4b5984fe8271551 (patch) | |
| tree | a0662dbc4228a7b9fa3a0a9f6e19f8235b55b033 /kernel | |
| parent | 97d402e6eed2f7d867a9f57d9d35a968c1440fe8 (diff) | |
tracing: Erase irqsoff trace with empty write
commit 8dd33bcb7050dd6f8c1432732f930932c9d3a33e upstream.
One convenient way to erase trace is "echo > trace". However, this
is currently broken if the current tracer is irqsoff tracer. This
is because irqsoff tracer use max_buffer as the default trace
buffer.
Set the max_buffer as the one to be cleared when it's the trace
buffer currently in use.
Link: http://lkml.kernel.org/r/1505754215-29411-1-git-send-email-byan@nvidia.com
Cc: <mingo@redhat.com>
Fixes: 4acd4d00f ("tracing: give easy way to clear trace buffer")
Signed-off-by: Bo Yan <byan@nvidia.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 3074fc5f713c..c1e50cc0d7b0 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3569,11 +3569,17 @@ static int tracing_open(struct inode *inode, struct file *file) /* If this file was open for write, then erase contents */ if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { int cpu = tracing_get_cpu(inode); + struct trace_buffer *trace_buf = &tr->trace_buffer; + +#ifdef CONFIG_TRACER_MAX_TRACE + if (tr->current_trace->print_max) + trace_buf = &tr->max_buffer; +#endif if (cpu == RING_BUFFER_ALL_CPUS) - tracing_reset_online_cpus(&tr->trace_buffer); + tracing_reset_online_cpus(trace_buf); else - tracing_reset(&tr->trace_buffer, cpu); + tracing_reset(trace_buf, cpu); } if (file->f_mode & FMODE_READ) { |