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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5CEAAC4332F for ; Thu, 14 Dec 2023 22:27:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E946A8D00F2; Thu, 14 Dec 2023 17:27:23 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E43C68D00C7; Thu, 14 Dec 2023 17:27:23 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CE4878D00F2; Thu, 14 Dec 2023 17:27:23 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id BA7058D00C7 for ; Thu, 14 Dec 2023 17:27:23 -0500 (EST) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 918AE140C7B for ; Thu, 14 Dec 2023 22:27:23 +0000 (UTC) X-FDA: 81566861166.24.48ABDEA Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf01.hostedemail.com (Postfix) with ESMTP id 8D26340015 for ; Thu, 14 Dec 2023 22:27:21 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2023-11-20 header.b=Gx18r61u; dmarc=pass (policy=none) header.from=oracle.com; spf=pass (imf01.hostedemail.com: domain of jianfeng.w.wang@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=jianfeng.w.wang@oracle.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1702592841; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:references:dkim-signature; bh=vWebtL2rhfE1sZveziVMAIBgy0M/wp/MnldOKJtCGJA=; b=X0LsxK4XPa0/kPnDkzKhtmg9PwCoOiXYVg1lSkTC7mrjCUkoArwaMIayA3OGpHVnANo6Y3 w3eoqy0YTM9XYW96qtlEMHmKrWq7efbc7TwE4X6QSkaOtmKduXdz9Ru82Mp2LrE4wrF+UR wkKZX8t3CQ5Zy29bdAQHZSQlSs8jygg= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2023-11-20 header.b=Gx18r61u; dmarc=pass (policy=none) header.from=oracle.com; spf=pass (imf01.hostedemail.com: domain of jianfeng.w.wang@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=jianfeng.w.wang@oracle.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1702592841; a=rsa-sha256; cv=none; b=4YXcKh+aq8k7YklimZ7hH8Ya3aTXP1MKNll4IWJE4lcowzIExuFkKTgw+Pfd3vAzVwMTN2 RBVEizc73aFbjByQfBK3TEfth27kjmFEc7o5bz/5+5WumJ7UclFAZ11g58/9sL8y77o51O Dq/+fn0OzQWt/Z56biTGUwcc5TdENdg= Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3BEMHP2J032548; Thu, 14 Dec 2023 22:27:20 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=corp-2023-11-20; bh=vWebtL2rhfE1sZveziVMAIBgy0M/wp/MnldOKJtCGJA=; b=Gx18r61ud07Dn6edn9pWwaJ7Z63e0Kz9zITNQAXzM0QfCuGWEI90KvM7sS4J0Dh5GxEL UGMtJreLR2/0op/a1T3XQ+z6JWTJrkLd61aj7rU6OajKxZ8siqrOkW73yEdN2T89ektb //FuSiaGwXxFikHP50hwbuFwWSzt+QY9q3U+zmaN2Vz6PwcHMsi0270MYEi6QL7n4ybv hUqlLV7pS+lencdsArH6e1iRvIwRgwwPO7BP7yWQWkXUvMOS5unrLiRC1tZz0o/KqoqK ljlY1leGL10IqEcKY4Im1bMXEp3w1KsGePr9jWaKyPrpMaFejUYZqQsehQXb3lk+osZH 7Q== Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.appoci.oracle.com [138.1.114.2]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3uvgsum0rw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 14 Dec 2023 22:27:20 +0000 Received: from pps.filterd (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 3BELD9D8008284; Thu, 14 Dec 2023 22:27:19 GMT Received: from pps.reinject (localhost [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 3uvepaug4d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 14 Dec 2023 22:27:19 +0000 Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3BEMRImB001139; Thu, 14 Dec 2023 22:27:19 GMT Received: from jfwang-mac.us.oracle.com (dhcp-10-65-130-157.vpn.oracle.com [10.65.130.157]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTP id 3uvepaug41-1; Thu, 14 Dec 2023 22:27:18 +0000 From: Jianfeng Wang To: akpm@linux-foundation.org Cc: tim.c.chen@linux.intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jianfeng Wang Subject: [PATCH v2] mm: remove redundant lru_add_drain() prior to unmapping pages Date: Thu, 14 Dec 2023 14:27:17 -0800 Message-ID: <20231214222717.50277-1-jianfeng.w.wang@oracle.com> X-Mailer: git-send-email 2.42.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-14_15,2023-12-14_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 malwarescore=0 mlxlogscore=999 adultscore=0 phishscore=0 suspectscore=0 mlxscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311290000 definitions=main-2312140159 X-Proofpoint-ORIG-GUID: 7K-1cvQBvkGHX_8Z6IKaJyasvuhRD8p7 X-Proofpoint-GUID: 7K-1cvQBvkGHX_8Z6IKaJyasvuhRD8p7 X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 8D26340015 X-Stat-Signature: tzbchif7d9o5guoy68t9h9jkbzfze17o X-Rspam-User: X-HE-Tag: 1702592841-461872 X-HE-Meta: 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 kE7Gi2j0 eMHCum+98f+Zen38zCXM3QtOvH+63ScOXQcPqS9GCXcIdjbgQcQXtcaxEG3EnqK27Xu8mfpwdBXw3MLIVG/VluCYnaabHf25rvRMiIekuDCZECQUseDte3oJ9YMhsL1ZhcaxeTp+eIxpyOxt+rbBqkCmJRqGrZR6vM1gbWnpPFboiPXl1zL0hcRFTQvu1zoc/NtYVkvBrCJvwWRbj5U29jyf0sFLcFJaLbbpPZSzpfBWowhK9h9bGZ/0mAkKC6Is+C4tI 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: List-Subscribe: List-Unsubscribe: When unmapping VMA pages, pages will be gathered in batch and released by tlb_finish_mmu() if CONFIG_MMU_GATHER_NO_GATHER is not set. The function tlb_finish_mmu() is responsible for calling free_pages_and_swap_cache(), which calls lru_add_drain() to drain cached pages in folio_batch before releasing gathered pages. Thus, it is redundant to call lru_add_drain() before gathering pages, if CONFIG_MMU_GATHER_NO_GATHER is not set. Remove lru_add_drain() prior to gathering and unmapping pages in exit_mmap() and unmap_region() if CONFIG_MMU_GATHER_NO_GATHER is not set. Note that the page unmapping process in oom_killer (e.g., in __oom_reap_task_mm()) also uses tlb_finish_mmu() and does not have redundant lru_add_drain(). So, this commit makes the code more consistent. Signed-off-by: Jianfeng Wang --- mm/mmap.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index 1971bfffcc03..da0308eef435 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2330,7 +2330,10 @@ static void unmap_region(struct mm_struct *mm, struct ma_state *mas, struct mmu_gather tlb; unsigned long mt_start = mas->index; + /* Defer lru_add_drain() to tlb_finish_mmu() for the ifndef case. */ +#ifdef CONFIG_MMU_GATHER_NO_GATHER lru_add_drain(); +#endif tlb_gather_mmu(&tlb, mm); update_hiwater_rss(mm); unmap_vmas(&tlb, mas, vma, start, end, tree_end, mm_wr_locked); @@ -3300,7 +3303,10 @@ void exit_mmap(struct mm_struct *mm) return; } + /* Defer lru_add_drain() to tlb_finish_mmu() for the ifndef case. */ +#ifdef CONFIG_MMU_GATHER_NO_GATHER lru_add_drain(); +#endif flush_cache_mm(mm); tlb_gather_mmu_fullmm(&tlb, mm); /* update_hiwater_rss(mm) here? but nobody should be looking */ -- 2.42.1