From patchwork Tue Oct 11 01:00:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13003482 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C07BBC433F5 for ; Tue, 11 Oct 2022 01:01:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B924E900002; Mon, 10 Oct 2022 21:01:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AA040900003; Mon, 10 Oct 2022 21:01:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 88BBE8E0005; Mon, 10 Oct 2022 21:01:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 4F767900002 for ; Mon, 10 Oct 2022 21:01:23 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 19CDB1607CE for ; Tue, 11 Oct 2022 01:01:23 +0000 (UTC) X-FDA: 80006865246.27.3DE3704 Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by imf18.hostedemail.com (Postfix) with ESMTP id 9E8981C0022 for ; Tue, 11 Oct 2022 01:01:22 +0000 (UTC) Received: by dev1180.prn1.facebook.com (Postfix, from userid 425415) id 1EFC534BDDE0; Mon, 10 Oct 2022 18:01:06 -0700 (PDT) From: Stefan Roesch To: kernel-team@fb.com, linux-block@vger.kernel.org, linux-mm@kvack.org Cc: shr@devkernel.io, axboe@kernel.dk, clm@meta.com Subject: [RFC PATCH v1 09/14] mm: document new /sys/class/bdi//max_bytes knob Date: Mon, 10 Oct 2022 18:00:39 -0700 Message-Id: <20221011010044.851537-10-shr@devkernel.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221011010044.851537-1-shr@devkernel.io> References: <20221011010044.851537-1-shr@devkernel.io> MIME-Version: 1.0 ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1665450082; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FG2YZJniK6WQyGMVTRehiSJED6hFD5pcUkGd65cLNIA=; b=gm2KJ7XvuJhFXz+Fc3MT4baSydKGLWao1uiJN/oAcjKGRR/71jSdH1lMwIZtIikanV31Ct /f9e2k3Bj1CIOdVYqDddQ2FijrnscaSLNuEFCiQyT1WhZJpxciWRnJk++Q9+wvNJZ9wnds 0UyPfMyeg5bWd7+7qCvS154Gk5ralf4= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf18.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1665450082; a=rsa-sha256; cv=none; b=PoMGH9JXaUJEHlOoBfBFuxJS3ccckzMBVMNTlfcWLHSVp0w1Q+bfdzC/EyXOWb6rfrOUeb BCv2tszoywGpbw3Y5mfgCqNfVa2YrbbKYHfCthG72lR4OVhB1G4UquRo119LE56fJVPV9X Knras37mida4mI7eIEfK3VXhUdQikZE= Authentication-Results: imf18.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf18.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io X-Stat-Signature: 1r3r6qk45r7fkkd3azm1bbye3f3ofcas X-Rspamd-Queue-Id: 9E8981C0022 X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1665450082-199252 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: This documents the new /sys/class/bdi//max_bytes knob. Signed-off-by: Stefan Roesch --- Documentation/ABI/testing/sysfs-class-bdi | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi index 68b5d4018c2f..580f723de049 100644 --- a/Documentation/ABI/testing/sysfs-class-bdi +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -56,6 +56,20 @@ Description: be trusted to play fair. (read-write) + +What: /sys/class/bdi//max_bytes +Date: October 2022 +Contact: Stefan Roesch +Description: + Allows limiting a particular device to use not more than the + given 'max_bytes' of the write-back cache. This is useful in + situations where we want to avoid one device taking all or + most of the write-back cache. For example in case of an NFS + mount that is prone to get stuck, a FUSE mount which cannot be + trusted to play fair, or a nbd device. + + (read-write) + What: /sys/class/bdi//strict_limit Date: October 2022 Contact: Stefan Roesch