From patchwork Thu Mar 18 12:27:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12148077 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B2CFC433E0 for ; Thu, 18 Mar 2021 12:28:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 04FDB64F59 for ; Thu, 18 Mar 2021 12:28:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 04FDB64F59 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A0C386B0074; Thu, 18 Mar 2021 08:28:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8BDC06B007E; Thu, 18 Mar 2021 08:28:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5D42B6B007B; Thu, 18 Mar 2021 08:28:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0108.hostedemail.com [216.40.44.108]) by kanga.kvack.org (Postfix) with ESMTP id 3FF026B0074 for ; Thu, 18 Mar 2021 08:28:10 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id E6AD2181AF5C2 for ; Thu, 18 Mar 2021 12:28:09 +0000 (UTC) X-FDA: 77932922298.22.35E1BC2 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) by imf29.hostedemail.com (Postfix) with ESMTP id 13AA5EF for ; Thu, 18 Mar 2021 12:28:08 +0000 (UTC) Received: from DGGEMS406-HUB.china.huawei.com (unknown [172.30.72.58]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4F1R8M4zTQzrYRw; Thu, 18 Mar 2021 20:26:11 +0800 (CST) Received: from huawei.com (10.175.104.175) by DGGEMS406-HUB.china.huawei.com (10.3.19.206) with Microsoft SMTP Server id 14.3.498.0; Thu, 18 Mar 2021 20:27:57 +0800 From: Miaohe Lin To: CC: , , , , , , , , , , , , , , Subject: [PATCH v3 3/6] mm/huge_memory.c: rework the function do_huge_pmd_numa_page() slightly Date: Thu, 18 Mar 2021 08:27:19 -0400 Message-ID: <20210318122722.13135-4-linmiaohe@huawei.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20210318122722.13135-1-linmiaohe@huawei.com> References: <20210318122722.13135-1-linmiaohe@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.104.175] X-CFilter-Loop: Reflected X-Stat-Signature: shbgof3t5cseub459tu7isbgeteoy6am X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 13AA5EF Received-SPF: none (huawei.com>: No applicable sender policy available) receiver=imf29; identity=mailfrom; envelope-from=""; helo=szxga05-in.huawei.com; client-ip=45.249.212.191 X-HE-DKIM-Result: none/none X-HE-Tag: 1616070488-39354 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: The current code that checks if migrating misplaced transhuge page is needed is pretty hard to follow. Rework it and add a comment to make its logic more clear and improve readability. Signed-off-by: Miaohe Lin --- mm/huge_memory.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 01b96c638e73..23964adf5db2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1462,12 +1462,6 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd) */ page_locked = trylock_page(page); target_nid = mpol_misplaced(page, vma, haddr); - if (target_nid == NUMA_NO_NODE) { - /* If the page was locked, there are no parallel migrations */ - if (page_locked) - goto clear_pmdnuma; - } - /* Migration could have started since the pmd_trans_migrating check */ if (!page_locked) { page_nid = NUMA_NO_NODE; @@ -1476,6 +1470,11 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf, pmd_t pmd) spin_unlock(vmf->ptl); put_and_wait_on_page_locked(page, TASK_UNINTERRUPTIBLE); goto out; + } else if (target_nid == NUMA_NO_NODE) { + /* There are no parallel migrations and page is in the right + * node. Clear the numa hinting info in this pmd. + */ + goto clear_pmdnuma; } /*