]> git.karo-electronics.de Git - linux-beck.git/commit
perf_counter: fix perf_poll()
authorPeter Zijlstra <peterz@infradead.org>
Tue, 24 Mar 2009 12:18:16 +0000 (13:18 +0100)
committerIngo Molnar <mingo@elte.hu>
Mon, 6 Apr 2009 07:30:32 +0000 (09:30 +0200)
commitc7138f37f905bb7987b1f9f5a8ee73667db39f25
tree8d1c2bf404f1179d35e8b35b0166c7bf0b39840e
parentf66c6b2066b44d4ab8e8ac1ee4cae543738fe2ac
perf_counter: fix perf_poll()

Impact: fix kerneltop 100% CPU usage

Only return a poll event when there's actually been one, poll_wait()
doesn't actually wait for the waitq you pass it, it only enqueues
you on it.

Only once all FDs have been iterated and none of thm returned a
poll-event will it schedule().

Also make it return POLL_HUP when there's not mmap() area to read from.

Further, fix a silly bug in the write code.

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Orig-LKML-Reference: <1237897096.24918.181.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
include/linux/perf_counter.h
kernel/perf_counter.c