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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 2CA63C07E99 for ; Mon, 12 Jul 2021 11:34:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E0E2E60C40 for ; Mon, 12 Jul 2021 11:34:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0E2E60C40 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E04F66B0098; Mon, 12 Jul 2021 07:34:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D89BB6B009D; Mon, 12 Jul 2021 07:34:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C030A8D0001; Mon, 12 Jul 2021 07:34:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0193.hostedemail.com [216.40.44.193]) by kanga.kvack.org (Postfix) with ESMTP id 9266E6B0098 for ; Mon, 12 Jul 2021 07:34:48 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id B0733184B2F05 for ; Mon, 12 Jul 2021 11:34:47 +0000 (UTC) X-FDA: 78353728614.26.F4F03FD Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf26.hostedemail.com (Postfix) with ESMTP id 6E04820019DE; Mon, 12 Jul 2021 11:34:46 +0000 (UTC) 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=Nyp5QtyWvgSaxX6QcYvHcVd8PYTJFQ9djhzXeIBYfvk=; b=Q0MJVrgX1K/L21RKm04jXk5ehp 7Mco119wFA9kHR2lVhC23RoT0AMqrr9VIxszWDKBxGFIZuYrxr1OBwN1HsQTXiPJBtP96uOK0WKvb GRdtvM503qLkIItvYkTORx9iI9qdDxBNVKKCNToOv9UeJc2o0TlqX0zdbzbBZr1YRT5vw0GY1+oSo fgDmcVsjQ0OqU6teaRsVHt3+qqlFkmjmro0SgRp4FwlAvEve90LSAW5owp2rbu7ajJtuYdNIiTmoM 2Tjq+tYRF2zLFz51Df2U3dnwaqqRTgs+t1k+wjPP074qDuvZGM+Er0v4PARodzTWwM7H2klLH2406 5+JfWJQA==; Received: from hch by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1m2uCd-00HYHN-IS; Mon, 12 Jul 2021 11:34:28 +0000 Date: Mon, 12 Jul 2021 12:34:23 +0100 From: Christoph Hellwig To: "Matthew Wilcox (Oracle)" Cc: Jens Axboe , io-uring@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org Subject: Re: [PATCH 1/2] mm/readahead: Add gfp_flags to ractl Message-ID: References: <20210711150927.3898403-1-willy@infradead.org> <20210711150927.3898403-2-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210711150927.3898403-2-willy@infradead.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 6E04820019DE X-Stat-Signature: 3qzpdig4bpazg8mcb3irxrj91gzidt8j Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=Q0MJVrgX; dmarc=none; spf=none (imf26.hostedemail.com: domain of BATV@casper.srs.infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=BATV@casper.srs.infradead.org X-HE-Tag: 1626089686-119742 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Jul 11, 2021 at 04:09:26PM +0100, Matthew Wilcox (Oracle) wrote: > It is currently possible for an I/O request that specifies IOCB_NOWAIT > to sleep waiting for I/O to complete in order to allocate pages for > readahead. In order to fix that, we need the caller to be able to > specify the GFP flags to use for memory allocation in the rest of the > readahead path. The file systems also need to respect it for their bio or private data allocation. And be able to cope with failure, which they currently don't have to for sleeping bio allocations.