From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751048Ab2AYSbL (ORCPT ); Wed, 25 Jan 2012 13:31:11 -0500 Received: from mail-tul01m020-f174.google.com ([209.85.214.174]:57451 "EHLO mail-tul01m020-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832Ab2AYSbJ (ORCPT ); Wed, 25 Jan 2012 13:31:09 -0500 Date: Wed, 25 Jan 2012 19:31:03 +0100 From: Frederic Weisbecker To: "Kirill A. Shutemov" Cc: LKML , Li Zefan , Johannes Weiner , Aditya Kali , Oleg Nesterov , Kay Sievers , Tim Hockin , Tejun Heo , Andrew Morton Subject: Re: [PATCH 1/8] cgroups: add res_counter_write_u64() API Message-ID: <20120125183100.GD20878@somewhere> References: <1326478441-3048-1-git-send-email-fweisbec@gmail.com> <1326478441-3048-4-git-send-email-fweisbec@gmail.com> <20120116122713.GA25863@shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120116122713.GA25863@shutemov.name> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 16, 2012 at 02:27:13PM +0200, Kirill A. Shutemov wrote: > On Fri, Jan 13, 2012 at 07:13:47PM +0100, Frederic Weisbecker wrote: > > Extend the resource counter API with a mirror of res_counter_read_u64() to > > make it handy to update a resource counter value from a cgroup subsystem > > u64 value file. > > I still think it worth to have two versions of res_counter_write_u64(). > From my POV, it's clean enough, but consistent with res_counter_read_u64() > and faster on 64bit system. > > What do you think? Yeah right let's do this. Can I get your signed-off-by to take the below? Thanks. > > --- > diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h > index c9d625c..1b3fe05 100644 > --- a/include/linux/res_counter.h > +++ b/include/linux/res_counter.h > @@ -82,6 +82,8 @@ int res_counter_memparse_write_strategy(const char *buf, > int res_counter_write(struct res_counter *counter, int member, > const char *buffer, write_strategy_fn write_strategy); > > +void res_counter_write_u64(struct res_counter *counter, int member, u64 val); > + > /* > * the field descriptors. one for each member of res_counter > */ > diff --git a/kernel/res_counter.c b/kernel/res_counter.c > index 6d269cc..aad4ddb 100644 > --- a/kernel/res_counter.c > +++ b/kernel/res_counter.c > @@ -167,12 +167,27 @@ int res_counter_memparse_write_strategy(const char *buf, > return 0; > } > > +#if BITS_PER_LONG == 32 > +void res_counter_write_u64(struct res_counter *counter, int member, u64 val) > +{ > + unsigned long flags; > + > + spin_lock_irqsave(&counter->lock, flags); > + *res_counter_member(counter, member) = val; > + spin_unlock_irqrestore(&counter->lock, flags); > +} > +#else > +void res_counter_write_u64(struct res_counter *counter, int member, u64 val) > +{ > + *res_counter_member(counter, member) = val; > +} > +#endif > + > int res_counter_write(struct res_counter *counter, int member, > const char *buf, write_strategy_fn write_strategy) > { > char *end; > - unsigned long flags; > - unsigned long long tmp, *val; > + unsigned long long tmp; > > if (write_strategy) { > if (write_strategy(buf, &tmp)) > @@ -182,9 +197,8 @@ int res_counter_write(struct res_counter *counter, int member, > if (*end != '\0') > return -EINVAL; > } > - spin_lock_irqsave(&counter->lock, flags); > - val = res_counter_member(counter, member); > - *val = tmp; > - spin_unlock_irqrestore(&counter->lock, flags); > + > + res_counter_write_u64(counter, member, tmp); > + > return 0; > } > -- > Kirill A. Shutemov