From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 17 Jul 2007 12:32:43 -0400 From: Josef Sipek Subject: Re: [PATCH 05/17] lib: percpu_count_sum_signed() Message-ID: <20070717163243.GA15421@filer.fsl.cs.sunysb.edu> References: <20070614215817.389524447@chello.nl> <20070614220446.659716697@chello.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070614220446.659716697@chello.nl> Sender: owner-linux-mm@kvack.org Return-Path: To: Peter Zijlstra Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, miklos@szeredi.hu, akpm@linux-foundation.org, neilb@suse.de, dgc@sgi.com, tomoki.sekiyama.qu@hitachi.com, nikita@clusterfs.com, trond.myklebust@fys.uio.no, yingchao.zhou@gmail.com, andrea@suse.de List-ID: On Thu, Jun 14, 2007 at 11:58:22PM +0200, Peter Zijlstra wrote: > Provide an accurate version of percpu_counter_read. > > Should we go and replace the current use of percpu_counter_sum() > with percpu_counter_sum_positive(), and call this new primitive > percpu_counter_sum() instead? > > Signed-off-by: Peter Zijlstra > --- > include/linux/percpu_counter.h | 18 +++++++++++++++++- > lib/percpu_counter.c | 6 +++--- > 2 files changed, 20 insertions(+), 4 deletions(-) > > Index: linux-2.6/include/linux/percpu_counter.h > =================================================================== > --- linux-2.6.orig/include/linux/percpu_counter.h 2007-05-23 20:37:54.000000000 +0200 > +++ linux-2.6/include/linux/percpu_counter.h 2007-05-23 20:38:09.000000000 +0200 > @@ -35,7 +35,18 @@ void percpu_counter_destroy(struct percp > void percpu_counter_set(struct percpu_counter *fbc, s64 amount); > void __percpu_counter_mod(struct percpu_counter *fbc, s32 amount, s32 batch); > void __percpu_counter_mod64(struct percpu_counter *fbc, s64 amount, s32 batch); > -s64 percpu_counter_sum(struct percpu_counter *fbc); > +s64 __percpu_counter_sum(struct percpu_counter *fbc); > + > +static inline s64 percpu_counter_sum(struct percpu_counter *fbc) > +{ > + s64 ret = __percpu_counter_sum(fbc); > + return ret < 0 ? 0 : ret; max(0, ret) maybe? Josef 'Jeff' Sipek. -- Real Programmers consider "what you see is what you get" to be just as bad a concept in Text Editors as it is in women. No, the Real Programmer wants a "you asked for it, you got it" text editor -- complicated, cryptic, powerful, unforgiving, dangerous. -- 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/ . Don't email: email@kvack.org