From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755183Ab2GWXvq (ORCPT ); Mon, 23 Jul 2012 19:51:46 -0400 Received: from mail-yx0-f174.google.com ([209.85.213.174]:40103 "EHLO mail-yx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755159Ab2GWXvn (ORCPT ); Mon, 23 Jul 2012 19:51:43 -0400 From: Kent Overstreet To: linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org, dm-devel@redhat.com Cc: Kent Overstreet , tj@kernel.org, vgoyal@redhat.com, joe@perches.com Subject: [Bcache v15 01/16] Revert "rw_semaphore: remove up/down_read_non_owner" Date: Mon, 23 Jul 2012 16:50:44 -0700 Message-Id: <1343087459-17645-2-git-send-email-koverstreet@google.com> X-Mailer: git-send-email 1.7.7.3 In-Reply-To: <1343087459-17645-1-git-send-email-koverstreet@google.com> References: <1343087459-17645-1-git-send-email-koverstreet@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This reverts commit 11b80f459adaf91a712f95e7734a17655a36bf30. Signed-off-by: Kent Overstreet --- include/linux/rwsem.h | 10 ++++++++++ kernel/rwsem.c | 16 ++++++++++++++++ 2 files changed, 26 insertions(+), 0 deletions(-) diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h index 54bd7cd..ddfe46d 100644 --- a/include/linux/rwsem.h +++ b/include/linux/rwsem.h @@ -125,9 +125,19 @@ extern void downgrade_write(struct rw_semaphore *sem); */ extern void down_read_nested(struct rw_semaphore *sem, int subclass); extern void down_write_nested(struct rw_semaphore *sem, int subclass); +/* + * Take/release a lock when not the owner will release it. + * + * [ This API should be avoided as much as possible - the + * proper abstraction for this case is completions. ] + */ +extern void down_read_non_owner(struct rw_semaphore *sem); +extern void up_read_non_owner(struct rw_semaphore *sem); #else # define down_read_nested(sem, subclass) down_read(sem) # define down_write_nested(sem, subclass) down_write(sem) +# define down_read_non_owner(sem) down_read(sem) +# define up_read_non_owner(sem) up_read(sem) #endif #endif /* _LINUX_RWSEM_H */ diff --git a/kernel/rwsem.c b/kernel/rwsem.c index 6850f53..78b7915 100644 --- a/kernel/rwsem.c +++ b/kernel/rwsem.c @@ -116,6 +116,15 @@ void down_read_nested(struct rw_semaphore *sem, int subclass) EXPORT_SYMBOL(down_read_nested); +void down_read_non_owner(struct rw_semaphore *sem) +{ + might_sleep(); + + __down_read(sem); +} + +EXPORT_SYMBOL(down_read_non_owner); + void down_write_nested(struct rw_semaphore *sem, int subclass) { might_sleep(); @@ -126,6 +135,13 @@ void down_write_nested(struct rw_semaphore *sem, int subclass) EXPORT_SYMBOL(down_write_nested); +void up_read_non_owner(struct rw_semaphore *sem) +{ + __up_read(sem); +} + +EXPORT_SYMBOL(up_read_non_owner); + #endif -- 1.7.7.3