From patchwork Mon Oct 17 18:13:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13009242 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 75E30C4332F for ; Mon, 17 Oct 2022 18:16:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 102868E000D; Mon, 17 Oct 2022 14:16:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0B4168E0007; Mon, 17 Oct 2022 14:16:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EE5668E000D; Mon, 17 Oct 2022 14:16:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id D86588E0007 for ; Mon, 17 Oct 2022 14:16:58 -0400 (EDT) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 8736D1A016E for ; Mon, 17 Oct 2022 18:16:58 +0000 (UTC) X-FDA: 80031247716.28.BBAAEE9 Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by imf24.hostedemail.com (Postfix) with ESMTP id 2D4B0180033 for ; Mon, 17 Oct 2022 18:16:57 +0000 (UTC) Received: by dev1180.prn1.facebook.com (Postfix, from userid 425415) id 5B60139C99CE; Mon, 17 Oct 2022 11:13:56 -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 v2 14/14] mm: document /sys/class/bdi//min_bytes knob Date: Mon, 17 Oct 2022 11:13:37 -0700 Message-Id: <20221017181337.3884657-15-shr@devkernel.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221017181337.3884657-1-shr@devkernel.io> References: <20221017181337.3884657-1-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=1666030618; 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=3EUi6jPj2vZbV6ealsadFNrxvkct4936SBuSwS/JJic=; b=n0wNTIU3YfYNvjS9zN/vza7uw3pT23I6ZNGrTzZDzS1I0uBamaVKfkFCW03wVQ7ILl0JHg PxufVOrY0RAWpZTd7AqBvCJduvblc08SOuB6OKIlq/NJ4M2bph8UDaKV8yzXUajQC4GXkX 6J/zF+MGXie2/tYq5O36zeAShs/WXx8= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=none; spf=neutral (imf24.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666030618; a=rsa-sha256; cv=none; b=bJ8VVEwj7x4nf42YKzJae+tN9vmoHDwfLueTIxMq9Oche0NtP/3Y/b4H+DcUKTbY5Cr5Nc 9oitFrjDKKKyDmS3ZJn7ahAapruURbR95fCBiCz7Z3HUQwqh8JF2fLHTXlLg9HnhzkrJrI k7KKACh0XvpMuS676IPZcf/Xs2F5Zr8= X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 2D4B0180033 X-Rspam-User: Authentication-Results: imf24.hostedemail.com; dkim=none; spf=neutral (imf24.hostedemail.com: 66.220.144.178 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io; dmarc=none X-Stat-Signature: tf1dt7cufsaj9bbwyt4stxgghfno1dq9 X-HE-Tag: 1666030617-95589 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//min_bytes knob. Signed-off-by: Stefan Roesch --- Documentation/ABI/testing/sysfs-class-bdi | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi index 580f723de049..bec996e29565 100644 --- a/Documentation/ABI/testing/sysfs-class-bdi +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -57,6 +57,21 @@ Description: (read-write) +What: /sys/class/bdi//min_bytes +Date: October 2022 +Contact: Stefan Roesch +Description: + Under normal circumstances each device is given a part of the + total write-back cache that relates to its current average + writeout speed in relation to the other devices. + + The 'min_bytes' parameter allows assigning a minimum + percentage of the write-back cache to a particular device + expressed in bytes. + For example, this is useful for providing a minimum QoS. + + (read-write) + What: /sys/class/bdi//max_bytes Date: October 2022 Contact: Stefan Roesch