From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx165.postini.com [74.125.245.165]) by kanga.kvack.org (Postfix) with SMTP id A24996B003D for ; Thu, 18 Apr 2013 19:49:27 -0400 (EDT) Received: from m4.gw.fujitsu.co.jp (unknown [10.0.50.74]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id C31DC3EE0B6 for ; Fri, 19 Apr 2013 08:49:25 +0900 (JST) Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id A81ED45DE55 for ; Fri, 19 Apr 2013 08:49:25 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 8DC8345DE50 for ; Fri, 19 Apr 2013 08:49:25 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 7DFEC1DB803E for ; Fri, 19 Apr 2013 08:49:25 +0900 (JST) Received: from g01jpexchyt35.g01.fujitsu.local (g01jpexchyt35.g01.fujitsu.local [10.128.193.50]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 318F71DB8037 for ; Fri, 19 Apr 2013 08:49:25 +0900 (JST) Message-ID: <5170853B.2040807@jp.fujitsu.com> Date: Fri, 19 Apr 2013 08:43:55 +0900 From: Yasuaki Ishimatsu MIME-Version: 1.0 Subject: Re: [Bug fix PATCH v4] Reusing a resource structure allocated by bootmem References: <516FB07C.9010603@jp.fujitsu.com> <1366295000.3824.47.camel@misato.fc.hp.com> <517082B9.7050708@jp.fujitsu.com> <1366327735.3824.50.camel@misato.fc.hp.com> In-Reply-To: <1366327735.3824.50.camel@misato.fc.hp.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Toshi Kani Cc: akpm@linux-foundation.org, linuxram@us.ibm.com, rientjes@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org 2013/04/19 8:28, Toshi Kani wrote: > On Fri, 2013-04-19 at 08:33 +0900, Yasuaki Ishimatsu wrote: > : >>> >>>> +static struct resource *get_resource(gfp_t flags) >>>> +{ >>>> + struct resource *res = NULL; >>>> + >>>> + spin_lock(&bootmem_resource_lock); >>>> + if (bootmem_resource.sibling) { >>>> + res = bootmem_resource.sibling; >>>> + bootmem_resource.sibling = res->sibling; >>>> + memset(res, 0, sizeof(struct resource)); >>>> + } >>>> + spin_unlock(&bootmem_resource_lock); >>> >> >>> I prefer to keep memset() outside of the spin lock. >>> >>> spin_lock(&bootmem_resource_lock); >>> if (..) { >>> : >>> spin_unlock(&bootmem_resource_lock); >>> memset(res, 0, sizeof(struct resource)); >>> } else { >>> spin_unlock(&bootmem_resource_lock); >>> res = kzalloc(sizeof(struct resource), flags); >>> } >> >> Hmm. It is a little ugly. How about it? >> >> spin_lock(&bootmem_resource_lock); >> if (bootmem_resource.sibling) { >> res = bootmem_resource.sibling; >> bootmem_resource.sibling = res->sibling; >> } >> spin_unlock(&bootmem_resource_lock); >> >> if (res) >> memset(res, 0, sizeof(struct resource)); >> else >> res = kzalloc(sizeof(struct resource), flags); > > Sounds good to me. Great. I'll update it. Thanks, Yasuaki Ishimatsu > > Thanks, > -Toshi > > -- 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