[tip:core/locking] printk: Make console_sem a semaphore not a pseudo mutex

From: tip-bot for Thomas Gleixner
Date: Tue Oct 12 2010 - 11:53:31 EST


Commit-ID: 5b8c4f23c54edda640a4850bc9b81dee70acb525
Gitweb: http://git.kernel.org/tip/5b8c4f23c54edda640a4850bc9b81dee70acb525
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Tue, 7 Sep 2010 14:33:43 +0000
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Tue, 12 Oct 2010 17:36:10 +0200

printk: Make console_sem a semaphore not a pseudo mutex

It needs to be investigated whether it can be replaced by a real
mutex, but that needs more thought.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
LKML-Reference: <20100907125057.179587334@xxxxxxxxxxxxx>

---
kernel/printk.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/printk.c b/kernel/printk.c
index 8fe465a..2531017 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -85,7 +85,7 @@ EXPORT_SYMBOL(oops_in_progress);
* provides serialisation for access to the entire console
* driver system.
*/
-static DECLARE_MUTEX(console_sem);
+static DEFINE_SEMAPHORE(console_sem);
struct console *console_drivers;
EXPORT_SYMBOL_GPL(console_drivers);

@@ -556,7 +556,7 @@ static void zap_locks(void)
/* If a crash is occurring, make sure we can't deadlock */
spin_lock_init(&logbuf_lock);
/* And make sure that we print immediately */
- init_MUTEX(&console_sem);
+ sema_init(&console_sem, 1);
}

#if defined(CONFIG_PRINTK_TIME)
--
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