From mboxrd@z Thu Jan 1 00:00:00 1970 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 6710BC433EF for ; Tue, 21 Jun 2022 02:40:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344920AbiFUCkj (ORCPT ); Mon, 20 Jun 2022 22:40:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244545AbiFUCkh (ORCPT ); Mon, 20 Jun 2022 22:40:37 -0400 Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B02C1F624 for ; Mon, 20 Jun 2022 19:40:36 -0700 (PDT) Received: by mail-pf1-x432.google.com with SMTP id p14so6135407pfh.6 for ; Mon, 20 Jun 2022 19:40:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:to:cc:references :from:in-reply-to:content-transfer-encoding; bh=MAxGrYPRrn3PDrCT6+3wEqy3eFiNsK2NRcJPeVZeG8Y=; b=VW7TBZ7AhbUaLY1bMT0AIMf1zF4z/GCdtWfYA5qth8EnqLEmZCPvDNjAFBrikMfKNO 6BLseU+zvq4Gtk0mx4TfSV3FgigKHWuAI9dUL7uVcA7IPGtI2rJKqSlGoky6xQliKmj+ LDpZSNzZFCvOMHa0Zi77QcpVCuBa47cONxkzCyu+fSFuid2Uloj9uD1XKZP4s+n43DdQ Pj6ZRsWHTd2tFmTTltXpp3BkuIaY+J2AsMVxUHjRNkTcf8aWi7AfrglV3LqIM6PdTshA u9MEj1l3jpRgMhxIEGnAoHigsclOwZEv+PsEQE5pEP4TbNvIz/nUrMm4HQM1w/bHXQeC 0EnQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :to:cc:references:from:in-reply-to:content-transfer-encoding; bh=MAxGrYPRrn3PDrCT6+3wEqy3eFiNsK2NRcJPeVZeG8Y=; b=jtzs8VPbaZ54MCzaIe0WTPb+qp36uanm8Bk0qWDJeJtRvyUW+joCdRFmHj5D1nZi+B OnPNiQcVKqzA+RwaMqJW3+SggPz1DdqBvQBqlCGCDMcP/0Bfrov7jpaW07gcUiD9v8Jd mgu2OVLNHVUiJbutsoZ5E8KOgBoQxC7k8ycEXXWkp7PQv+UFzMLodUH9r3Qr0ZWTfUY1 7N++GM1kC0uhxvnv+c8zqv3s4fl5iD+Jjm/B1iUmM4VnvnfERa/mqe/CPeW7OgbngbyR VDk06Gsyy7TgLjXVF+l97Ucw/6K5NC9nTsJ2I31FATRaKl9kXkRNusZge5N3aIZlGKSN qsiA== X-Gm-Message-State: AJIora9flwHwY5w6xHJ58NGINELE8pmHTBeJQPMzsn8cyWqfLof66PMD /4T2j3Usn92hdx1xDjWVLYamCpjTFVB4eg== X-Google-Smtp-Source: AGRyM1sRVqR4TPQ7hzPO5xLtJI0dp5o82s+eN+/tAD+iVCtZICpWioOkfJVo3hOKTVfpBf5zMVnxRw== X-Received: by 2002:a62:6411:0:b0:50a:81df:bfa6 with SMTP id y17-20020a626411000000b0050a81dfbfa6mr28143915pfb.26.1655779235852; Mon, 20 Jun 2022 19:40:35 -0700 (PDT) Received: from [10.76.33.147] ([61.120.150.69]) by smtp.gmail.com with ESMTPSA id j11-20020aa7928b000000b005251ce498cfsm3787737pfa.191.2022.06.20.19.40.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Jun 2022 19:40:35 -0700 (PDT) Message-ID: <2a95ca55-4088-583b-9a28-cf9f4c0f32fc@bytedance.com> Date: Tue, 21 Jun 2022 10:40:30 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH] ext4: reuse order and buddy in mb_mark_used when buddy split To: tytso@mit.edu, adilger.kernel@dilger.ca Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, lei.rao@intel.com References: <20220606155305.74146-1-hanjinke.666@bytedance.com> From: hanjinke In-Reply-To: <20220606155305.74146-1-hanjinke.666@bytedance.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi, friendly pinging... 在 2022/6/6 下午11:53, Jinke Han 写道: > 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, struct ext4_free_extent *ex) > unsigned ret = 0; > int len0 = len; > void *buddy; > + bool split = false; > > BUG_ON(start + len > (e4b->bd_sb->s_blocksize << 3)); > BUG_ON(e4b->bd_group != ex->fe_group); > @@ -1957,12 +1958,16 @@ static int mb_mark_used(struct ext4_buddy *e4b, struct ext4_free_extent *ex) > > /* let's maintain buddy itself */ > while (len) { > - ord = mb_find_order_for_block(e4b, start); > + if (!split) > + ord = mb_find_order_for_block(e4b, start); > > if (((start >> ord) << ord) == start && len >= (1 << ord)) { > /* the whole chunk may be allocated at once! */ > mlen = 1 << ord; > - buddy = mb_find_buddy(e4b, ord, &max); > + if (!split) > + buddy = mb_find_buddy(e4b, ord, &max); > + else > + split = false; > BUG_ON((start >> ord) >= 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, struct ext4_free_extent *ex) > mb_clear_bit(cur + 1, buddy); > e4b->bd_info->bb_counters[ord]++; > e4b->bd_info->bb_counters[ord]++; > + split = true; > } > mb_set_largest_free_order(e4b->bd_sb, e4b->bd_info); >