From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 27 Jun 2018 09:17:11 -0400 From: Mike Snitzer To: Ming Lei Cc: Jens Axboe , Christoph Hellwig , Kent Overstreet , David Sterba , Huang Ying , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Theodore Ts'o , "Darrick J . Wong" , Coly Li , Filipe Manana , Randy Dunlap , stable@vger.kernel.org Subject: Re: [PATCH V7 01/24] dm: use bio_split() when splitting out the already processed bio Message-ID: <20180627131711.GA11531@redhat.com> References: <20180627124548.3456-1-ming.lei@redhat.com> <20180627124548.3456-2-ming.lei@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180627124548.3456-2-ming.lei@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: On Wed, Jun 27 2018 at 8:45am -0400, Ming Lei wrote: > From: Mike Snitzer > > Use of bio_clone_bioset() is inefficient if there is no need to clone > the original bio's bio_vec array. Best to use the bio_clone_fast() > variant. Also, just using bio_advance() is only part of what is needed > to properly setup the clone -- it doesn't account for the various > bio_integrity() related work that also needs to be performed (see > bio_split). > > Address both of these issues by switching from bio_clone_bioset() to > bio_split(). > > Fixes: 18a25da8 ("dm: ensure bio submission follows a depth-first tree walk") > Cc: stable@vger.kernel.org > Reported-by: Christoph Hellwig > Reviewed-by: NeilBrown > Reviewed-by: Ming Lei > Signed-off-by: Mike Snitzer FYI, I'll be sending this to Linus tomorrow. Mike