Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756248AbbDKAHB (ORCPT ); Fri, 10 Apr 2015 20:07:01 -0400 Received: from mail.kernel.org ([198.145.29.136]:43647 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753261AbbDKAG7 (ORCPT ); Fri, 10 Apr 2015 20:06:59 -0400 MIME-Version: 1.0 In-Reply-To: References: <1427210823-5283-1-git-send-email-axboe@fb.com> <1427210823-5283-4-git-send-email-axboe@fb.com> <20150325024328.GF31342@dastard> <5512C588.2050805@kernel.dk> Date: Fri, 10 Apr 2015 17:06:55 -0700 Message-ID: Subject: Re: [PATCH 3/6] direct-io: add support for write stream IDs From: Ming Lin To: Ming Lin Cc: Jens Axboe , Dave Chinner , Jens Axboe , lkml , linux-fsdevel@vger.kernel.org, ming.l@ssi.samsung.com Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2599 Lines: 81 On Fri, Apr 10, 2015 at 4:50 PM, Ming Lin wrote: > On Wed, Mar 25, 2015 at 7:26 AM, Jens Axboe wrote: >> On 03/24/2015 08:43 PM, Dave Chinner wrote: >>> >>> On Tue, Mar 24, 2015 at 09:27:00AM -0600, Jens Axboe wrote: >>>> >>>> Get the streamid from the file, if any, and set it on the bio. >>>> >>>> Signed-off-by: Jens Axboe >>>> --- >>>> fs/direct-io.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >>>> >>>> diff --git a/fs/direct-io.c b/fs/direct-io.c >>>> index e181b6b2e297..5d2750346451 100644 >>>> --- a/fs/direct-io.c >>>> +++ b/fs/direct-io.c >>>> @@ -77,6 +77,7 @@ struct dio_submit { >>>> int reap_counter; /* rate limit reaping */ >>>> sector_t final_block_in_request;/* doesn't change */ >>>> int boundary; /* prev block is at a boundary */ >>>> + int streamid; /* Write stream ID */ >>>> get_block_t *get_block; /* block mapping function */ >>>> dio_submit_t *submit_io; /* IO submition function */ >>>> >>>> @@ -372,6 +373,8 @@ dio_bio_alloc(struct dio *dio, struct dio_submit >>>> *sdio, >>>> >>>> sdio->bio = bio; >>>> sdio->logical_offset_in_bio = sdio->cur_page_fs_offset; >>>> + >>>> + bio_set_streamid(bio, sdio->streamid); >>>> } >>>> >>>> /* >>>> @@ -1205,6 +1208,7 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, >>>> struct inode *inode, >>>> sdio.blkbits = blkbits; >>>> sdio.blkfactor = i_blkbits - blkbits; >>>> sdio.block_in_file = offset >> blkbits; >>>> + sdio.streamid = iocb->ki_filp->f_streamid; >>> >>> >>> If iocb->ki_filp->f_streamid is not set, then it should fall back to >>> whatever is set on the inode->i_streamid. > > Why should do the fall back? > >> >> >> Good point, agree. Will make that change. > > Hi Jens, > > That change causes problem for direct IO, for example Actually, buffered write also has problem. process 1: fd = open("/mnt/foo.txt", ...); //set stream_id 1 fadvise(fd, 1, 0, POSIX_FADV_STREAMID); write(fd, ....); process 1 exit, but stream_id is still saved in inode later process 2 starts, and when writeback it will see stream_id 1 from inode although it didn't set stream_id at all process 2: fd = open("/mnt/foo.txt", ...); write(fd, ....); Thanks, Ming -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/