From nobody Tue Feb 10 13:16:20 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 DCB45EB64DD for ; Thu, 10 Aug 2023 01:53:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232221AbjHJBxI (ORCPT ); Wed, 9 Aug 2023 21:53:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232124AbjHJBxF (ORCPT ); Wed, 9 Aug 2023 21:53:05 -0400 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6DE25C5 for ; Wed, 9 Aug 2023 18:53:05 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4RLqgx5D5jz4f3mHy for ; Thu, 10 Aug 2023 09:53:01 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgCXJ6r8QtRkiaZjAQ--.27199S4; Thu, 10 Aug 2023 09:53:02 +0800 (CST) From: Kemeng Shi To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, baolin.wang@linux.alibaba.com, mgorman@techsingularity.net, david@redhat.com, willy@infradead.org Cc: shikemeng@huaweicloud.com Subject: [PATCH 2/3] mm/page_alloc: remove unnecessary check in break_down_buddy_pages Date: Thu, 10 Aug 2023 17:53:08 +0800 Message-Id: <20230810095309.3109107-3-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20230810095309.3109107-1-shikemeng@huaweicloud.com> References: <20230810095309.3109107-1-shikemeng@huaweicloud.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: gCh0CgCXJ6r8QtRkiaZjAQ--.27199S4 X-Coremail-Antispam: 1UD129KBjvdXoW7XF4rWr48Kr18Wr1rWw1xZrb_yoWDAFb_ua n7tr95tFy5KF1IgF17C3W7GrWkWw1F9w4xWF4YgFsxKa4UAFnxta1kXFyrJr1Duay8ur98 W3ZxArW2qr1a9jkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbqAYFVCjjxCrM7AC8VAFwI0_Wr0E3s1l1xkIjI8I6I8E6xAIw20E Y4v20xvaj40_Wr0E3s1l1IIY67AEw4v_Jr0_Jr4l87I20VAvwVAaII0Ic2I_JFv_Gryl82 xGYIkIc2x26280x7IE14v26r15M28IrcIa0xkI8VCY1x0267AKxVW8JVW5JwA2ocxC64kI II0Yj41l84x0c7CEw4AK67xGY2AK021l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7 xvwVC0I7IYx2IY6xkF7I0E14v26r4UJVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2 z4x0Y4vEx4A2jsIEc7CjxVAFwI0_GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4 xG64xvF2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v2 6r1j6r4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6I AqYI8I648v4I1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAq x4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r 43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF 7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxV WUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjTR QNVDUUUUU X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 1. We always have target in range started with next_page and full free range started with current_buddy. 2. The last splited range size is 1 << low and low should be >=3D 0, then size >=3D 1, then page + size and page will not interleave. As summary, current_page will not equal to target page. Signed-off-by: Kemeng Shi --- mm/page_alloc.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fd93d1396ccd..d0b400733031 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6562,10 +6562,8 @@ static void break_down_buddy_pages(struct zone *zone= , struct page *page, if (set_page_guard(zone, current_buddy, high, migratetype)) continue; =20 - if (current_buddy !=3D target) { - add_to_free_list(current_buddy, zone, high, migratetype); - set_buddy_order(current_buddy, high); - } + add_to_free_list(current_buddy, zone, high, migratetype); + set_buddy_order(current_buddy, high); } } =20 --=20 2.30.0