From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161304Ab3DEDpb (ORCPT ); Thu, 4 Apr 2013 23:45:31 -0400 Received: from mail-da0-f45.google.com ([209.85.210.45]:62569 "EHLO mail-da0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932222Ab3DEDp3 (ORCPT ); Thu, 4 Apr 2013 23:45:29 -0400 Message-ID: <515E48D1.2090505@gmail.com> Date: Fri, 05 Apr 2013 11:45:21 +0800 From: Ric Mason User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130308 Thunderbird/17.0.4 MIME-Version: 1.0 To: "Kirill A. Shutemov" CC: Andrea Arcangeli , Andrew Morton , Al Viro , Hugh Dickins , Wu Fengguang , Jan Kara , Mel Gorman , linux-mm@kvack.org, Andi Kleen , Matthew Wilcox , "Kirill A. Shutemov" , Hillf Danton , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCHv2, RFC 07/30] thp, mm: introduce mapping_can_have_hugepages() predicate References: <1363283435-7666-1-git-send-email-kirill.shutemov@linux.intel.com> <1363283435-7666-8-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1363283435-7666-8-git-send-email-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kirill, On 03/15/2013 01:50 AM, Kirill A. Shutemov wrote: > From: "Kirill A. Shutemov" > > Returns true if mapping can have huge pages. Just check for __GFP_COMP > in gfp mask of the mapping for now. > > Signed-off-by: Kirill A. Shutemov > --- > include/linux/pagemap.h | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h > index e3dea75..3521b0d 100644 > --- a/include/linux/pagemap.h > +++ b/include/linux/pagemap.h > @@ -84,6 +84,16 @@ static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) > (__force unsigned long)mask; > } > > +static inline bool mapping_can_have_hugepages(struct address_space *m) > +{ > + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { > + gfp_t gfp_mask = mapping_gfp_mask(m); > + return !!(gfp_mask & __GFP_COMP); I always see !! in kernel, but why check directly instead of have !! prefix? > + } > + > + return false; > +} > + > /* > * The page cache can done in larger chunks than > * one page, because it allows for more efficient From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ric Mason Subject: Re: [PATCHv2, RFC 07/30] thp, mm: introduce mapping_can_have_hugepages() predicate Date: Fri, 05 Apr 2013 11:45:21 +0800 Message-ID: <515E48D1.2090505@gmail.com> References: <1363283435-7666-1-git-send-email-kirill.shutemov@linux.intel.com> <1363283435-7666-8-git-send-email-kirill.shutemov@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Andrea Arcangeli , Andrew Morton , Al Viro , Hugh Dickins , Wu Fengguang , Jan Kara , Mel Gorman , linux-mm@kvack.org, Andi Kleen , Matthew Wilcox , "Kirill A. Shutemov" , Hillf Danton , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: "Kirill A. Shutemov" Return-path: In-Reply-To: <1363283435-7666-8-git-send-email-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org Hi Kirill, On 03/15/2013 01:50 AM, Kirill A. Shutemov wrote: > From: "Kirill A. Shutemov" > > Returns true if mapping can have huge pages. Just check for __GFP_COMP > in gfp mask of the mapping for now. > > Signed-off-by: Kirill A. Shutemov > --- > include/linux/pagemap.h | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h > index e3dea75..3521b0d 100644 > --- a/include/linux/pagemap.h > +++ b/include/linux/pagemap.h > @@ -84,6 +84,16 @@ static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) > (__force unsigned long)mask; > } > > +static inline bool mapping_can_have_hugepages(struct address_space *m) > +{ > + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { > + gfp_t gfp_mask = mapping_gfp_mask(m); > + return !!(gfp_mask & __GFP_COMP); I always see !! in kernel, but why check directly instead of have !! prefix? > + } > + > + return false; > +} > + > /* > * The page cache can done in larger chunks than > * one page, because it allows for more efficient -- 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