tree 03c16d8f6f3ec24408adbe9042bc42546725141a
parent 63f01241176d7cbc976385aec32f0a209b0bc36a
author Steven Rostedt <srostedt@redhat.com> 1291673431 -0500
committer Steven Rostedt <rostedt@goodmis.org> 1292288203 -0500

sched: Remove unlikely() from ttwu_post_activation

The unlikely() used in ttwu_post_activation() tests if the rq->idle_stamp
is set. But since this is for a wakeup, and wakeups happen when tasks
block on IO, and blocking tasks on IO may put the system into idle,
this can actually be a common occurence.

Running the annotated branch profiler on an average desktop running
firefox, evolution, xchat and distcc, the report shows:

 correct incorrect  %        Function             File              Line
 ------- ---------  -        --------             ----              ----
34884862 146110926  80 ttwu_post_activation      sched.c            2309

80% of the time, this unlikely is incorrect. Best not to assume what the
result is, and just remove the branch annotation.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>