From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx129.postini.com [74.125.245.129]) by kanga.kvack.org (Postfix) with SMTP id A92B36B0006 for ; Thu, 14 Mar 2013 07:31:00 -0400 (EDT) Received: from /spool/local by e28smtp08.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 14 Mar 2013 16:56:38 +0530 Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id D7EEDE004A for ; Thu, 14 Mar 2013 17:02:16 +0530 (IST) Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r2EBUohk5374294 for ; Thu, 14 Mar 2013 17:00:50 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r2EBUqiD006483 for ; Thu, 14 Mar 2013 22:30:54 +1100 From: Wanpeng Li Subject: [PATCH v3] mm/hugetlb: fix total hugetlbfs pages count when memory overcommit accouting Date: Thu, 14 Mar 2013 19:30:46 +0800 Message-Id: <1363260646-26896-1-git-send-email-liwanp@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Greg Kroah-Hartman , Michal Hocko , "Aneesh Kumar K.V" , Hillf Danton , KAMEZAWA Hiroyuki , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Wanpeng Li Changelog: v2 -> v3: * update patch description, spotted by Michal v1 -> v2: * update patch description, spotted by Michal "hugetlb_total_pages is used for overcommit calculations but the current implementation considers only default hugetlb page size (which is either the first defined hugepage size or the one specified by default_hugepagesz kernel boot parameter). If the system is configured for more than one hugepage size (which is possible since a137e1cc hugetlbfs: per mount huge page sizes) then the overcommit estimation done by __vm_enough_memory (resp. shown by meminfo_proc_show) is not precise - there is an impression of more available/allowed memory. This can lead to an unexpected ENOMEM/EFAULT resp. SIGSEGV when memory is accounted." The patch should also push to 2.6.27 stable tree. Testcase: boot: hugepagesz=1G hugepages=1 the default overcommit ratio is 50 before patch: egrep 'CommitLimit' /proc/meminfo CommitLimit: 55434168 kB after patch: egrep 'CommitLimit' /proc/meminfo CommitLimit: 54909880 kB Signed-off-by: Wanpeng Li --- mm/hugetlb.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index cdb64e4..9e25040 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2124,8 +2124,11 @@ int hugetlb_report_node_meminfo(int nid, char *buf) /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ unsigned long hugetlb_total_pages(void) { - struct hstate *h = &default_hstate; - return h->nr_huge_pages * pages_per_huge_page(h); + struct hstate *h; + unsigned long nr_total_pages = 0; + for_each_hstate(h) + nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); + return nr_total_pages; } static int hugetlb_acct_memory(struct hstate *h, long delta) -- 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