Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752690AbaJYTqd (ORCPT ); Sat, 25 Oct 2014 15:46:33 -0400 Received: from mail-qc0-f169.google.com ([209.85.216.169]:45158 "EHLO mail-qc0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751573AbaJYTqc (ORCPT ); Sat, 25 Oct 2014 15:46:32 -0400 Message-ID: <544B4534.4030204@gmail.com> Date: Sat, 25 Oct 2014 02:37:40 -0400 From: "Michael L. Semon" User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: "Martin K. Petersen" CC: linux-kernel@vger.kernel.org, axboe@fb.com Subject: Re: Slow dc3dd in 3.18 on x86 References: <544AA317.8070609@gmail.com> <544AEEF1.30506@gmail.com> In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/24/14 21:51, Martin K. Petersen wrote: >>>>>> "Michael" == Michael L Semon writes: > > Michael> There was nothing regarding integrity in /sys/block/sda. I was > Michael> under the impression that both bio integrity and T10 checksums > Michael> require hardware support from good hardware, so the config > Michael> items have always been shut off. > > That's correct. But I see what's going on. > > Please try this: > > commit 8d331952d2cd341d5c0e64eee961f78f6eb4b968 > Author: Martin K. Petersen > Date: Fri Oct 24 21:39:12 2014 -0400 > > block: Fix merge logic when CONFIG_BLK_DEV_INTEGRITY is not defined > > Commit 4eaf99beadce switched to returning bool and as a result > reversed the logic of the integrity merge checks. However, the > empty stubs used when the block integrity code is compiled out were > still returning 0. Make these stubs return "true". > > Reported-by: Michael L. Semon > Signed-off-by: Martin K. Petersen > > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index 9fbf4d3196ed..7442c6b9187e 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -1590,13 +1590,13 @@ static inline bool blk_integrity_merge_rq(struct request_queue *rq, > struct request *r1, > struct request *r2) > { > - return 0; > + return true; > } > static inline bool blk_integrity_merge_bio(struct request_queue *rq, > struct request *r, > struct bio *b) > { > - return 0; > + return true; > } > static inline bool blk_integrity_is_initialized(struct gendisk *g) > { > Excellent! All is well with the problem kernel. All is well with the night's git master + xfs-oss/for-next as well. The saved E-mail patched cleanly against both kernels using `git am`. About 40 GB of data was written, some using fio, most using dc3dd. No problems. I'll keep this patch and stand behind its good results so far. Thanks again! Michael -- 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/