From patchwork Sat Apr 16 06:11:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wonhyuk Yang X-Patchwork-Id: 12815688 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 1BBE1C433F5 for ; Sat, 16 Apr 2022 06:11:15 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5D8776B0072; Sat, 16 Apr 2022 02:11:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5882A6B0073; Sat, 16 Apr 2022 02:11:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 450426B0074; Sat, 16 Apr 2022 02:11:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0210.hostedemail.com [216.40.44.210]) by kanga.kvack.org (Postfix) with ESMTP id 349A96B0072 for ; Sat, 16 Apr 2022 02:11:15 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id DFD0DA565C for ; Sat, 16 Apr 2022 06:11:14 +0000 (UTC) X-FDA: 79361719668.29.BCB4DA9 Received: from mail-pj1-f54.google.com (mail-pj1-f54.google.com [209.85.216.54]) by imf11.hostedemail.com (Postfix) with ESMTP id 81CBF40002 for ; Sat, 16 Apr 2022 06:11:14 +0000 (UTC) Received: by mail-pj1-f54.google.com with SMTP id n11-20020a17090a73cb00b001d1d3a7116bso820224pjk.0 for ; Fri, 15 Apr 2022 23:11:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=bcOfBPL4OuuAG640SlARJZ6hb/FVaA7pZLG+NuBAIqI=; b=Nr9bl2Lz08LmMiCuXk2WBYjQ3ZmKPTXuZQS2+uFJ1CoadNQabr40ys3p22cNkg5BVK 1YThbJeevQDiujyTY5YVNqtAHT3QCkw8t8GqlDOPZncNJOwVv6YZASYqUOgZKLdCZrBk 9uPzDp1xjIrM3BjF1GsOjQjEOBi9oVUyqDErGdsYMM1O7hcf4dQWeuAQXk9IJHMBI0Sc V5cM2SGK1bWWxG67Si3NMEFkZDJTU9PFGhrRMJkRVqgHwCtkOKJSIdo1PvQgJuPoVTJH m0cTAELczTDhfJZKRRlon7bckFWhPdp0Qg9syoOVaLdTXxEHxyp/4D2B8Pg/okgVQhCV gFPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=bcOfBPL4OuuAG640SlARJZ6hb/FVaA7pZLG+NuBAIqI=; b=TusCSBxfE33jFu0JXVRtGOqDo7kDsSBsc6ZYzfsJIbVMw2WtRI63zRjcWZJga5SH5J 3nmJgZ3ZPja88f/HBU2jGIZ0t+5mg6Fo5k8lBXXAH4jnUOjtDb4dEHmFwGGXQbpqJbUT BBrImwcyLcd6PLP/a19DuSmNodiPs5Qh5Gp47OTFPdTV806jOGBuk4pHxzhrsHtaJqgV OCKKJiothflFHhtnd1llQDqrf6T1vcjX+UUm/7QPb4YTgA8gmspQYprWETUVIQunuJBP RQx7uWMXCrNBaPXakifE9lMsZIjcmwPrLkFx7sI4u4RtVyX5InQyoYqTvpS5vOgccv34 EJMw== X-Gm-Message-State: AOAM531KyoQB5dI8i7SCIlrz6voNvwZ57JGl6B/OHbA4bGjNFoHv6OVd DZ/fJFq0IH0OS2Z+yVX9+xI= X-Google-Smtp-Source: ABdhPJwepZdppnnzYaQcm1cA/smdaAO5t6Oc4XxNF8dETGCwvJW/qEmZficFIgsPqhVBdyUuKHNRHA== X-Received: by 2002:a17:90b:1642:b0:1c6:c6d0:fbfa with SMTP id il2-20020a17090b164200b001c6c6d0fbfamr2466474pjb.218.1650089473414; Fri, 15 Apr 2022 23:11:13 -0700 (PDT) Received: from localhost.localdomain ([125.131.156.123]) by smtp.gmail.com with ESMTPSA id n12-20020a17090a670c00b001cbb7fdb9e4sm10428029pjj.53.2022.04.15.23.11.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Apr 2022 23:11:12 -0700 (PDT) From: Wonhyuk Yang To: vvghjk1234@gmail.com, Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH] mm/slub: Remove repeated action in calculate_order() Date: Sat, 16 Apr 2022 15:11:04 +0900 Message-Id: <20220416061104.481674-1-vvghjk1234@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 81CBF40002 X-Stat-Signature: 8fh4ycr88dxyw7cc94mmay78n3ezee1c Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=Nr9bl2Lz; spf=pass (imf11.hostedemail.com: domain of vvghjk1234@gmail.com designates 209.85.216.54 as permitted sender) smtp.mailfrom=vvghjk1234@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-HE-Tag: 1650089474-26905 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: To calculate order, calc_slab_order() is called repeatly changing the fract_leftover. Thus, the branch which is not dependent on fract_leftover is executed repeatly. So make it run only once. Plus, when min_object reached to 0, we set fract_leftover to 1. In this case, we can calculate order by max(slub_min_order, get_order(size) instead of calling calc_slab_order(). No functional impact expectd. Signed-off-by: Wonhyuk Yang --- mm/slub.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index ed5c2c03a47a..e7a394d7b75a 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -3795,9 +3795,6 @@ static inline unsigned int calc_slab_order(unsigned int size, unsigned int min_order = slub_min_order; unsigned int order; - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) - return get_order(size * MAX_OBJS_PER_PAGE) - 1; - for (order = max(min_order, (unsigned int)get_order(min_objects * size)); order <= max_order; order++) { @@ -3820,6 +3817,11 @@ static inline int calculate_order(unsigned int size) unsigned int max_objects; unsigned int nr_cpus; + if (unlikely(order_objects(slub_min_order, size) > MAX_OBJS_PER_PAGE)) { + order = get_order(size * MAX_OBJS_PER_PAGE) - 1; + goto out; + } + /* * Attempt to find best configuration for a slab. This * works by first attempting to generate a layout with @@ -3865,14 +3867,8 @@ static inline int calculate_order(unsigned int size) * We were unable to place multiple objects in a slab. Now * lets see if we can place a single object there. */ - order = calc_slab_order(size, 1, slub_max_order, 1); - if (order <= slub_max_order) - return order; - - /* - * Doh this slab cannot be placed using slub_max_order. - */ - order = calc_slab_order(size, 1, MAX_ORDER, 1); + order = max_t(unsigned int, slub_min_order, (unsigned int)get_order(size)); +out: if (order < MAX_ORDER) return order; return -ENOSYS;