From nobody Tue Apr 28 03:56:33 2026 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 6A342C433EF for ; Mon, 6 Jun 2022 15:51:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241265AbiFFPv4 (ORCPT ); Mon, 6 Jun 2022 11:51:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241266AbiFFPvx (ORCPT ); Mon, 6 Jun 2022 11:51:53 -0400 Received: from mail-pl1-x62a.google.com (mail-pl1-x62a.google.com [IPv6:2607:f8b0:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E837221684 for ; Mon, 6 Jun 2022 08:51:52 -0700 (PDT) Received: by mail-pl1-x62a.google.com with SMTP id i1so12424335plg.7 for ; Mon, 06 Jun 2022 08:51:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Hc9viEeZffCjBHu/ML1+/iUUNsF5FvYmtO3dN3G4Vlw=; b=kbPUnQSF99ZlyPwWnFMWPsmmeT5+u0GJl+ZGFTHeabKhMFFeDRnUeKGX3JhCSS+hY6 mMfS+PHJ9L5E095xRkAohdPXVJwDroRWIBlASitwNX9a3jAGrfYMSSDkqKcyUbDVXCul ruha7NS+uXWnUloG+ofrs0oYPnaI0Fp6cI5tGm0Va2Uh4gfskz3KLuwZksl4j4bc1Zai wppoYfumXRwL8ReXNQASidHso1uJrq1qx/g0f8or/mvDaG/HeoWDn4tbBUni0ZINeS3a IuYpHsffUxWApkozUXTvNEmul9Mwkyx//djSdvkunrnGH+v4GAJzi2f2WuINB6WhIKZs NydA== 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=Hc9viEeZffCjBHu/ML1+/iUUNsF5FvYmtO3dN3G4Vlw=; b=7R49XxE3ieiHq74SvxMT69Nx8tfy7lRFwV9Df/5byvzqF4tf0h8He6WGVNqvfIumCN lSY9JAROTp2Rw1e2XZWWe+/tsXzgGrTwr4Zcm5BqjxkS02xd6tsGXmCfJ/vfcSeBogiq GsVsXvBlqi1SEHZFw3YR1fyK/zc1eMOOtxks0YBKY4wvubxsCUVuCYhV4mhckIfltnQa Jr8/FNcu3A/HHf9XVLbqJPlCvY8qz3rk9oj2aG1n++fY8XKjIJK2p+tk3zbZ5+xjEcq3 u5jogtXX6XJINuCZ5Zu/P1r22ivqby6lvtc6GH54y3oOlMUkmI5Q52L1yRsWP5V+zuw7 y24g== X-Gm-Message-State: AOAM531s1kh7hAl6pP3YzVItx+ldQqnmcFZU4HmpCb/pFaZ95RykUJ9A +RRA6hhELJZksoKioE7Uv6bvFQ== X-Google-Smtp-Source: ABdhPJz1bjjwn40bEHChJRrt6r9mbuu8qPVpXZuGa83rsIpPLR8CGwZz5sF5cZ4nz3eGwVRCnTDvrA== X-Received: by 2002:a17:902:b908:b0:163:e462:704c with SMTP id bf8-20020a170902b90800b00163e462704cmr24524551plb.145.1654530712020; Mon, 06 Jun 2022 08:51:52 -0700 (PDT) Received: from C02GD5ZHMD6R.bytedance.net ([139.177.225.255]) by smtp.gmail.com with ESMTPSA id be3-20020a170902aa0300b001624b1e1a7bsm10941011plb.250.2022.06.06.08.51.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Jun 2022 08:51:51 -0700 (PDT) From: Jinke Han X-Google-Original-From: Jinke Han To: tytso@mit.edu, adilger.kernel@dilger.ca Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, lei.rao@intel.com, hanjinke Subject: [PATCH] ext4: reuse order and buddy in mb_mark_used when buddy split Date: Mon, 6 Jun 2022 23:51:25 +0800 Message-Id: <20220606155125.73990-1-hanjinke.666@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: hanjinke After each buddy split, mb_mark_used will search the proper order for the block which may consume some loop in mb_find_order_for_block. In fact, we can reuse the oder and buddy generated by the buddy split. Reviewed by: lei.rao@intel.com Signed-off-by: hanjinke --- fs/ext4/mballoc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 9f12f29bc346..c7ac6b269dd8 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1933,6 +1933,7 @@ static int mb_mark_used(struct ext4_buddy *e4b, struc= t ext4_free_extent *ex) unsigned ret =3D 0; int len0 =3D len; void *buddy; + bool split =3D false; =20 BUG_ON(start + len > (e4b->bd_sb->s_blocksize << 3)); BUG_ON(e4b->bd_group !=3D ex->fe_group); @@ -1957,12 +1958,16 @@ static int mb_mark_used(struct ext4_buddy *e4b, str= uct ext4_free_extent *ex) =20 /* let's maintain buddy itself */ while (len) { - ord =3D mb_find_order_for_block(e4b, start); + if (!split) + ord =3D mb_find_order_for_block(e4b, start); =20 if (((start >> ord) << ord) =3D=3D start && len >=3D (1 << ord)) { /* the whole chunk may be allocated at once! */ mlen =3D 1 << ord; - buddy =3D mb_find_buddy(e4b, ord, &max); + if (!split) + buddy =3D mb_find_buddy(e4b, ord, &max); + else + split =3D false; BUG_ON((start >> ord) >=3D max); mb_set_bit(start >> ord, buddy); e4b->bd_info->bb_counters[ord]--; @@ -1989,6 +1994,7 @@ static int mb_mark_used(struct ext4_buddy *e4b, struc= t ext4_free_extent *ex) mb_clear_bit(cur + 1, buddy); e4b->bd_info->bb_counters[ord]++; e4b->bd_info->bb_counters[ord]++; + split =3D true; } mb_set_largest_free_order(e4b->bd_sb, e4b->bd_info); =20 --=20 2.20.1