From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH] block: virtio_blk: don't hold spin lock during world switch Date: Fri, 30 May 2014 07:52:08 -0600 Message-ID: <53888D08.1050602@kernel.dk> References: <1401418169-3361-1-git-send-email-ming.lei@canonical.com> <5387F8B2.1070509@kernel.dk> <5387FC96.4030508@kernel.dk> <877g537q6d.fsf@rustcorp.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <877g537q6d.fsf@rustcorp.com.au> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Rusty Russell , Ming Lei Cc: virtualization@lists.linux-foundation.org, Linux Kernel Mailing List , "Michael S. Tsirkin" List-Id: virtualization@lists.linuxfoundation.org On 2014-05-30 00:10, Rusty Russell wrote: > Jens Axboe writes: >> If Rusty agrees, I'd like to add it for 3.16 with a stable marker. > > Really stable? It improves performance, which is nice. But every patch > which goes into the kernel fixes a bug, improves clarity, improves > performance or adds a feature. I've now seen all four cases get CC'd > into stable. > > Including some of mine explicitly not marked stable which get swept up > by enthusiastic stable maintainers :( > > Is now there *any* patch short of a major rewrite which shouldn't get > cc: stable? I agree that there's sometimes an unfortunate trend there. I didn't check, but my assumption was that this is a regression after the blk-mq conversion, in which case I do think it belongs in stable. But in any case, I think the patch is obviously correct and the wins are sufficiently large to warrant a stable inclusion even if it isn't a regression. -- Jens Axboe