From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65242C4338F for ; Wed, 11 Aug 2021 15:09:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3663160FC3 for ; Wed, 11 Aug 2021 15:09:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232614AbhHKPJZ (ORCPT ); Wed, 11 Aug 2021 11:09:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39394 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232440AbhHKPJY (ORCPT ); Wed, 11 Aug 2021 11:09:24 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5FF2C061765; Wed, 11 Aug 2021 08:09:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=PbTlBXx64xIBd6bp3wQXIQvhWlAavlmN4y7TyNwbpuk=; b=tFvG5zzwmlCgeXRZyUDMVBlE7S dKI9BlEVxJzt59ZILch9VXb/irkBlT3ptKkeWXTwy8kG6OigcdWzVCItMu22imlFyvbzezQ6JpDBH MNS70mGMpScRC0Cb3UyNCkasWB3SffuTl72GmaH7FkRQkEPQteDkEEIvmLIG7iiGhRXTKie9B58q3 y1pyIrvGtOmGZpBBfE9t2XF8EnrJdq7KC4vUo9j4OMV4Y9w5YmsYlycfsrGIazAXa81v2sg5E+Qz2 Cf4NBawI/2eUxqQc2vjQ69oxNuJAqlU8HDmSQp8t+8ZEFeiD57B41npv7jtJAmLK79Chef1uzOo6p 9bAvrl8A==; Received: from hch by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mDppu-00DXlz-Oq; Wed, 11 Aug 2021 15:08:13 +0000 Date: Wed, 11 Aug 2021 16:08:06 +0100 From: Christoph Hellwig To: Jens Axboe Cc: Christoph Hellwig , io-uring@vger.kernel.org, linux-block@vger.kernel.org Subject: Re: [PATCHSET v3 0/5] Enable bio recycling for polled IO Message-ID: References: <20210810163728.265939-1-axboe@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Wed, Aug 11, 2021 at 09:05:47AM -0600, Jens Axboe wrote: > On 8/11/21 5:13 AM, Christoph Hellwig wrote: > > On Wed, Aug 11, 2021 at 09:26:33AM +0100, Christoph Hellwig wrote: > >> I really don't like all the layering violations in here. What is the > >> problem with a simple (optional) percpu cache in the bio_set? Something > >> like the completely untested patch below: > > > > A slightly updated version that actually compiles and survives minimal > > testing is here: > > > > http://git.infradead.org/users/hch/block.git/shortlog/refs/heads/bio-cache > > I like this approach, I've done something very similar in the past. But > the key here is the opt-in, to avoid needing IRQ/locking for the cache > which defeats the purpose. That's why it was done just for polling, > obviously. > > I'll test a bit and re-spin the series. The series above now has the opt-in as I realized the same after a little testing.