From patchwork Mon Oct 24 19:05:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13017989 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 59DCAECAAA1 for ; Mon, 24 Oct 2022 19:06:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DB9B294000F; Mon, 24 Oct 2022 15:06:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D19FD94000C; Mon, 24 Oct 2022 15:06:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BBBBF94000F; Mon, 24 Oct 2022 15:06:32 -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 A10BC94000C for ; Mon, 24 Oct 2022 15:06:32 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 59CC180654 for ; Mon, 24 Oct 2022 19:06:32 +0000 (UTC) X-FDA: 80056774224.16.CCE17BB Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by imf08.hostedemail.com (Postfix) with ESMTP id CAF6416000E for ; Mon, 24 Oct 2022 19:06:31 +0000 (UTC) Received: by dev1180.prn1.facebook.com (Postfix, from userid 425415) id 7A4B63ED591A; Mon, 24 Oct 2022 12:06:12 -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, willy@infradead.org, hch@infradead.org Subject: [RFC PATCH v3 09/14] mm: document /sys/class/bdi//max_bytes knob Date: Mon, 24 Oct 2022 12:05:58 -0700 Message-Id: <20221024190603.3987969-10-shr@devkernel.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221024190603.3987969-1-shr@devkernel.io> References: <20221024190603.3987969-1-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=1666638391; 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=Yzs4g7j2Z0orKidRG1uNVE61lL1v3vwfAxvXopvwqqcVfHr1xVPUUoX5ntno4NUdRrut4W CwRnpymSpBCYR4FEjJB8bSTRgw5diKdEvAkHaivfg7+ItXWbzi5T5iK1UU/ZJrABKgLOsm 2l8gIjZ7NEiKa0BCthYFjAxuzUzArO8= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf08.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=1666638391; a=rsa-sha256; cv=none; b=thzr/Utxhd5ABukjq2BXulmS9mNAZeuo1i8WV+1RR5Vfb963jiBCWLQ1XzHPLmsrqxeDCQ TAW800KSP8Ni9LnuwHa6duJKrcuIqJtEyAdSE5UAwo5wpDv+BrcFAwZ0TnpktqKeCrh85R 4pLRG0qBafnaiFq6znKRtX4b0s/mDiU= X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: CAF6416000E X-Rspam-User: Authentication-Results: imf08.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf08.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: 96mgficq55pfnorspg4a5zwm1rdir5xa X-HE-Tag: 1666638391-758978 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