From: Nick Piggin Date: Thu, 23 Oct 2008 14:25:54 +0000 (+0200) Subject: oprofile: fix memory ordering X-Git-Tag: v2.6.28-rc4~11^2^2~3 X-Git-Url: http://bbs.cooldavid.org/git/?a=commitdiff_plain;h=cae042a73bb22fc4132b04ff94bd684456203089;p=net-next-2.6.git oprofile: fix memory ordering Regular bitops don't work as locks on all architectures. Also: can use non-atomic unlock as no concurrent stores to the word. Signed-off-by: Nick Piggin Signed-off-by: Robert Richter --- diff --git a/drivers/oprofile/event_buffer.c b/drivers/oprofile/event_buffer.c index d962ba0dd87..191a3202cec 100644 --- a/drivers/oprofile/event_buffer.c +++ b/drivers/oprofile/event_buffer.c @@ -105,7 +105,7 @@ static int event_buffer_open(struct inode *inode, struct file *file) if (!capable(CAP_SYS_ADMIN)) return -EPERM; - if (test_and_set_bit(0, &buffer_opened)) + if (test_and_set_bit_lock(0, &buffer_opened)) return -EBUSY; /* Register as a user of dcookies @@ -129,7 +129,7 @@ static int event_buffer_open(struct inode *inode, struct file *file) fail: dcookie_unregister(file->private_data); out: - clear_bit(0, &buffer_opened); + __clear_bit_unlock(0, &buffer_opened); return err; } @@ -141,7 +141,7 @@ static int event_buffer_release(struct inode *inode, struct file *file) dcookie_unregister(file->private_data); buffer_pos = 0; atomic_set(&buffer_ready, 0); - clear_bit(0, &buffer_opened); + __clear_bit_unlock(0, &buffer_opened); return 0; }