blktrace: fix the original blktrace

Currently the original blktrace, which is using relay and is used via
ioctl, is broken. You can use ftrace to see the output of blktrace,
but user-space blktrace is unusable.

It's broken by "blktrace: add ftrace plugin"
(c71a896154119f4ca9e89d6078f5f63ad60ef199)

 -	if (unlikely(bt->trace_state != Blktrace_running))
 +	if (unlikely(bt->trace_state != Blktrace_running || !blk_tracer_enabled))
		return;

With this patch, both ioctl and ftrace can be used, but of course you
can't use both of them at the same time.

Signed-off-by: Li Zefan <[email protected]>
Acked-by: Jens Axboe <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions