From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx188.postini.com [74.125.245.188]) by kanga.kvack.org (Postfix) with SMTP id 269416B005D for ; Fri, 4 Jan 2013 20:04:33 -0500 (EST) Received: from /spool/local by e28smtp01.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sat, 5 Jan 2013 06:33:17 +0530 Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id BD99FE004D for ; Sat, 5 Jan 2013 06:34:31 +0530 (IST) Received: from d28av03.in.ibm.com (d28av03.in.ibm.com [9.184.220.65]) by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r0514Kix46465152 for ; Sat, 5 Jan 2013 06:34:20 +0530 Received: from d28av03.in.ibm.com (loopback [127.0.0.1]) by d28av03.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r0514LRa029427 for ; Sat, 5 Jan 2013 12:04:22 +1100 Date: Sat, 5 Jan 2013 09:04:20 +0800 From: Wanpeng Li Subject: Re: [RFC PATCH] mm: memblock: fix wrong memmove size in memblock_merge_regions() Message-ID: <20130105010420.GA26319@hacker.(null)> Reply-To: Wanpeng Li References: <1357290650-25544-1-git-send-email-linfeng@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1357290650-25544-1-git-send-email-linfeng@cn.fujitsu.com> Sender: owner-linux-mm@kvack.org List-ID: To: Lin Feng Cc: akpm@linux-foundation.org, tj@kernel.org, mingo@kernel.org, yinghai@kernel.org, benh@kernel.crashing.org, tangchen@cn.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Fri, Jan 04, 2013 at 05:10:50PM +0800, Lin Feng wrote: >The memmove span covers from (next+1) to the end of the array, and the index >of next is (i+1), so the index of (next+1) is (i+2). So the size of remaining >array elements is (type->cnt - (i + 2)). > Make sense. Reviewed-by: Wanpeng Li >PS. It seems that memblock_merge_regions() could be made some improvement: >we need't memmove the remaining array elements until we find a none-mergable >element, but now we memmove everytime we find a neighboring compatible region. >I'm not sure if the trial is worth though. > >Cc: Tejun Heo >Signed-off-by: Lin Feng >--- > mm/memblock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >diff --git a/mm/memblock.c b/mm/memblock.c >index 6259055..85ce056 100644 >--- a/mm/memblock.c >+++ b/mm/memblock.c >@@ -314,7 +314,7 @@ static void __init_memblock memblock_merge_regions(struct memblock_type *type) > } > > this->size += next->size; >- memmove(next, next + 1, (type->cnt - (i + 1)) * sizeof(*next)); >+ memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next)); > type->cnt--; > } > } >-- >1.7.11.7 -- 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