tracing: Fix regression of trace_pipe
authorLiu Bo <bo.li.liu@oracle.com>
Mon, 14 Jan 2013 02:54:11 +0000 (10:54 +0800)
committerSteven Rostedt <rostedt@goodmis.org>
Mon, 14 Jan 2013 18:13:32 +0000 (13:13 -0500)
commit250bfd3d8e7e19cb649dd94689f0af2ce3474060
tree66d0a49e15d99b4dabcd80259cdd501952425663
parent2df8f8a6a897ebf4c5613b5be6103d33b2a21520
tracing: Fix regression of trace_pipe

Commit 0fb9656d "tracing: Make tracing_enabled be equal to tracing_on"
changes the behaviour of trace_pipe, ie. it makes trace_pipe return if
we've read something and tracing is enabled, and this means that we have
to 'cat trace_pipe' again and again while running tests.

IMO the right way is if tracing is enabled, we always block and wait for
ring buffer, or we may lose what we want since ring buffer's size is limited.

Link: http://lkml.kernel.org/r/1358132051-5410-1-git-send-email-bo.li.liu@oracle.com
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
kernel/trace/trace.c