From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f197.google.com (mail-wr0-f197.google.com [209.85.128.197]) by kanga.kvack.org (Postfix) with ESMTP id 030566B0333 for ; Fri, 24 Mar 2017 12:50:18 -0400 (EDT) Received: by mail-wr0-f197.google.com with SMTP id y90so4510630wrb.1 for ; Fri, 24 Mar 2017 09:50:17 -0700 (PDT) Received: from mail-wr0-x229.google.com (mail-wr0-x229.google.com. [2a00:1450:400c:c0c::229]) by mx.google.com with ESMTPS id b2si3423343wra.295.2017.03.24.09.50.16 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 24 Mar 2017 09:50:16 -0700 (PDT) Received: by mail-wr0-x229.google.com with SMTP id l43so5498667wre.1 for ; Fri, 24 Mar 2017 09:50:16 -0700 (PDT) Date: Fri, 24 Mar 2017 19:50:14 +0300 From: "Kirill A. Shutemov" Subject: Re: [PATCH v4 06/11] mm: thp: check pmd migration entry in common path Message-ID: <20170324165014.2ibdmurirjd4pa7r@node.shutemov.name> References: <20170313154507.3647-1-zi.yan@sent.com> <20170313154507.3647-7-zi.yan@sent.com> <20170324145042.bda52glerop5wydx@node.shutemov.name> <58D544B5.20102@cs.rutgers.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <58D544B5.20102@cs.rutgers.edu> Sender: owner-linux-mm@kvack.org List-ID: To: Zi Yan Cc: Zi Yan , linux-kernel@vger.kernel.org, linux-mm@kvack.org, kirill.shutemov@linux.intel.com, akpm@linux-foundation.org, minchan@kernel.org, vbabka@suse.cz, mgorman@techsingularity.net, mhocko@kernel.org, n-horiguchi@ah.jp.nec.com, khandual@linux.vnet.ibm.com, dnellans@nvidia.com On Fri, Mar 24, 2017 at 11:09:25AM -0500, Zi Yan wrote: > Kirill A. Shutemov wrote: > > On Mon, Mar 13, 2017 at 11:45:02AM -0400, Zi Yan wrote: > > Again. That's doesn't look right.. > > It will be changed: > > ptl = pmd_lock(mm, pmd); > +retry_locked: > + if (unlikely(!pmd_present(*pmd))) { > + if (likely(!(flags & FOLL_MIGRATION))) { > + spin_unlock(ptl); > + return no_page_table(vma, flags); > + } > + pmd_migration_entry_wait(mm, pmd); > + goto retry_locked; Nope. pmd_migration_entry_wait() unlocks the ptl. -- Kirill A. Shutemov -- 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