From patchwork Mon Oct 24 19:05:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13018165 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8AB07C67871 for ; Mon, 24 Oct 2022 21:07:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231783AbiJXVHo (ORCPT ); Mon, 24 Oct 2022 17:07:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232094AbiJXVH3 (ORCPT ); Mon, 24 Oct 2022 17:07:29 -0400 Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED417117035 for ; Mon, 24 Oct 2022 12:14:14 -0700 (PDT) Received: by dev1180.prn1.facebook.com (Postfix, from userid 425415) id 81FC93ED591C; 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 10/14] mm: add bdi_get_min_bytes() function. Date: Mon, 24 Oct 2022 12:05:59 -0700 Message-Id: <20221024190603.3987969-11-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 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This adds a function to return the specified value for min_bytes. It converts the stored min_ratio of the bdi to the corresponding bytes value. This is an approximation as it is based on the value that is returned by global_dirty_limits(), which can change. The returned value can be different than the value when the min_bytes value was set. Signed-off-by: Stefan Roesch --- include/linux/backing-dev.h | 1 + mm/page-writeback.c | 6 ++++++ 2 files changed, 7 insertions(+) diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 5eb1ae3410b2..621329f25bbe 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -105,6 +105,7 @@ static inline unsigned long wb_stat_error(void) /* BDI ratio is expressed as part per 1000 for finer granularity. */ #define BDI_RATIO_SCALE 10 +unsigned long long bdi_get_min_bytes(struct backing_dev_info *bdi); unsigned long long bdi_get_max_bytes(struct backing_dev_info *bdi); int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio); int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 21d7c1880ea8..69fc2866e625 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -740,6 +740,12 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio) } EXPORT_SYMBOL(bdi_set_max_ratio); +unsigned long long bdi_get_min_bytes(struct backing_dev_info *bdi) +{ + return bdi_get_bytes(bdi->min_ratio); +} +EXPORT_SYMBOL_GPL(bdi_get_min_bytes); + unsigned long long bdi_get_max_bytes(struct backing_dev_info *bdi) { return bdi_get_bytes(bdi->max_ratio);