From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751372AbWACKKf (ORCPT ); Tue, 3 Jan 2006 05:10:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751363AbWACKKe (ORCPT ); Tue, 3 Jan 2006 05:10:34 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:50140 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1751364AbWACKKS (ORCPT ); Tue, 3 Jan 2006 05:10:18 -0500 Date: Tue, 3 Jan 2006 11:10:09 +0100 From: Ingo Molnar To: lkml Cc: Linus Torvalds , Andrew Morton , Arjan van de Ven , Nicolas Pitre , Jes Sorensen , Al Viro , Oleg Nesterov , David Howells , Alan Cox , Christoph Hellwig , Andi Kleen , Russell King Subject: [patch 19/19] mutex subsystem, semaphore to completion: drivers/block/loop.c Message-ID: <20060103101009.GS23289@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=ALL_TRUSTED,AWL autolearn=no SpamAssassin version=3.0.3 -2.8 ALL_TRUSTED Did not pass through any untrusted hosts 0.9 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org convert the block loop device from semaphores to completions. Signed-off-by: Ingo Molnar ---- drivers/block/loop.c | 27 ++++++++++++--------------- include/linux/loop.h | 4 ++-- 2 files changed, 14 insertions(+), 17 deletions(-) Index: linux/drivers/block/loop.c =================================================================== --- linux.orig/drivers/block/loop.c +++ linux/drivers/block/loop.c @@ -514,12 +514,12 @@ static int loop_make_request(request_que lo->lo_pending++; loop_add_bio(lo, old_bio); spin_unlock_irq(&lo->lo_lock); - up(&lo->lo_bh_mutex); + complete(&lo->lo_bh_done); return 0; out: if (lo->lo_pending == 0) - up(&lo->lo_bh_mutex); + complete(&lo->lo_bh_done); spin_unlock_irq(&lo->lo_lock); bio_io_error(old_bio, old_bio->bi_size); return 0; @@ -580,23 +580,20 @@ static int loop_thread(void *data) lo->lo_pending = 1; /* - * up sem, we are running + * complete it, we are running */ - up(&lo->lo_sem); + complete(&lo->lo_done); for (;;) { int pending; - /* - * interruptible just to not contribute to load avg - */ - if (down_interruptible(&lo->lo_bh_mutex)) + if (wait_for_completion_interruptible(&lo->lo_bh_done)) continue; spin_lock_irq(&lo->lo_lock); /* - * could be upped because of tear-down, not pending work + * could be completed because of tear-down, not pending work */ if (unlikely(!lo->lo_pending)) { spin_unlock_irq(&lo->lo_lock); @@ -619,7 +616,7 @@ static int loop_thread(void *data) break; } - up(&lo->lo_sem); + complete(&lo->lo_done); return 0; } @@ -830,7 +827,7 @@ static int loop_set_fd(struct loop_devic set_blocksize(bdev, lo_blocksize); kernel_thread(loop_thread, lo, CLONE_KERNEL); - down(&lo->lo_sem); + wait_for_completion(&lo->lo_done); return 0; out_putf: @@ -896,10 +893,10 @@ static int loop_clr_fd(struct loop_devic lo->lo_state = Lo_rundown; lo->lo_pending--; if (!lo->lo_pending) - up(&lo->lo_bh_mutex); + complete(&lo->lo_bh_done); spin_unlock_irq(&lo->lo_lock); - down(&lo->lo_sem); + wait_for_completion(&lo->lo_done); lo->lo_backing_file = NULL; @@ -1276,8 +1273,8 @@ static int __init loop_init(void) if (!lo->lo_queue) goto out_mem4; init_MUTEX(&lo->lo_ctl_mutex); - init_MUTEX_LOCKED(&lo->lo_sem); - init_MUTEX_LOCKED(&lo->lo_bh_mutex); + init_completion(&lo->lo_done); + init_completion(&lo->lo_bh_done); lo->lo_number = i; spin_lock_init(&lo->lo_lock); disk->major = LOOP_MAJOR; Index: linux/include/linux/loop.h =================================================================== --- linux.orig/include/linux/loop.h +++ linux/include/linux/loop.h @@ -58,9 +58,9 @@ struct loop_device { struct bio *lo_bio; struct bio *lo_biotail; int lo_state; - struct semaphore lo_sem; + struct completion lo_done; + struct completion lo_bh_done; struct semaphore lo_ctl_mutex; - struct semaphore lo_bh_mutex; int lo_pending; request_queue_t *lo_queue;