From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx110.postini.com [74.125.245.110]) by kanga.kvack.org (Postfix) with SMTP id 1B9D06B003B for ; Mon, 16 Sep 2013 10:36:39 -0400 (EDT) Received: from /spool/local by e28smtp04.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 16 Sep 2013 20:06:36 +0530 Received: from d28relay05.in.ibm.com (d28relay05.in.ibm.com [9.184.220.62]) by d28dlp03.in.ibm.com (Postfix) with ESMTP id A99901258051 for ; Mon, 16 Sep 2013 20:06:38 +0530 (IST) Received: from d28av05.in.ibm.com (d28av05.in.ibm.com [9.184.220.67]) by d28relay05.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r8GEaT2p43581668 for ; Mon, 16 Sep 2013 20:06:30 +0530 Received: from d28av05.in.ibm.com (localhost [127.0.0.1]) by d28av05.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id r8GEaUQt007884 for ; Mon, 16 Sep 2013 20:06:31 +0530 From: "Aneesh Kumar K.V" Subject: Re: [PATCH v4] hugetlbfs: support split page table lock In-Reply-To: <1379117362-gwv3vrog-mutt-n-horiguchi@ah.jp.nec.com> References: <1379117362-gwv3vrog-mutt-n-horiguchi@ah.jp.nec.com> Date: Mon, 16 Sep 2013 20:06:30 +0530 Message-ID: <878uywbzpt.fsf@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi , linux-mm@kvack.org, Andrew Morton Cc: Alex Thorlton , Mel Gorman , Andi Kleen , Michal Hocko , KOSAKI Motohiro , Rik van Riel , Andrea Arcangeli , kirill.shutemov@linux.intel.com, linux-kernel@vger.kernel.org Naoya Horiguchi writes: > Hi, > > Kirill posted split_ptl patchset for thp today, so in this version > I post only hugetlbfs part. I added Kconfig variables in following > Kirill's patches (although without CONFIG_SPLIT_*_PTLOCK_CPUS.) > > This patch changes many lines, but all are in hugetlbfs specific code, > so I think we can apply this independent of thp patches. > ----- > From: Naoya Horiguchi > Date: Fri, 13 Sep 2013 18:12:30 -0400 > Subject: [PATCH v4] hugetlbfs: support split page table lock > > Currently all of page table handling by hugetlbfs code are done under > mm->page_table_lock. So when a process have many threads and they heavily > access to the memory, lock contention happens and impacts the performance. > > This patch makes hugepage support split page table lock so that we use > page->ptl of the leaf node of page table tree which is pte for normal pages > but can be pmd and/or pud for hugepages of some architectures. > > ChangeLog v4: > - introduce arch dependent macro ARCH_ENABLE_SPLIT_HUGETLB_PTLOCK > (only defined for x86 for now) > - rename USE_SPLIT_PTLOCKS_HUGETLB to USE_SPLIT_HUGETLB_PTLOCKS Can we have separate locking for THP and hugetlb ? Doesn't both require us to use same locking when updating pmd ? -aneesh -- 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