tracing: Fix read blocking on trace_pipe_raw
authorSteven Rostedt <srostedt@redhat.com>
Thu, 28 Feb 2013 18:44:11 +0000 (13:44 -0500)
committerSteven Rostedt <rostedt@goodmis.org>
Fri, 15 Mar 2013 04:34:49 +0000 (00:34 -0400)
commitb627344fef0c38fa4e3050348e168e46db87c905
treed828a640959fcb39667cbc56cd7cf8e75f34636f
parentcc60cdc952be09bca5b0bff9fefc7aa6185c3049
tracing: Fix read blocking on trace_pipe_raw

If the ring buffer is empty, a read to trace_pipe_raw wont block.
The tracing code has the infrastructure to wake up waiting readers,
but the trace_pipe_raw doesn't take advantage of that.

When a read is done to trace_pipe_raw without the O_NONBLOCK flag
set, have the read block until there's data in the requested buffer.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
kernel/trace/trace.c