From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 23 Sep 2002 23:03:40 +0530 From: Dipankar Sarma Subject: Re: 2.5.38-mm2 [PATCH] Message-ID: <20020923230340.A341@in.ibm.com> Reply-To: dipankar@in.ibm.com References: <3D8E96AA.C2FA7D8@digeo.com> <20020923151559.B29900@in.ibm.com> <3D8F4139.6BB60A35@digeo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3D8F4139.6BB60A35@digeo.com>; from akpm@digeo.com on Mon, Sep 23, 2002 at 09:28:41AM -0700 Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: lkml , "linux-mm@kvack.org" List-ID: On Mon, Sep 23, 2002 at 09:28:41AM -0700, Andrew Morton wrote: > #ifdef CONFIG_PREEMPTION > #define rcu_read_lock() preempt_disable() > #define rcu_read_unlock() preempt_enable() > #else > #define rcu_read_lock() do {} while(0) > #define rcu_read_unlock() do {} while(0) > #endif > > with > > #define rcu_read_lock() preempt_disable() > #define rcu_read_unlock() preempt_enable() > > because preempt_disable() is a no-op on CONFIG_PREEMPT=n anyway. This is fine. The original rcu_ltimer patch needed #ifdef CONFIG_PREEMPT, so that it could be easily used with 2.4. With preemption in 2.5, rcu_read_xxx() can be preempt_xxx(). Thanks -- Dipankar Sarma http://lse.sourceforge.net Linux Technology Center, IBM Software Lab, Bangalore, India. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/