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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8E375CAC5A5 for ; Tue, 23 Sep 2025 17:49:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E70888E0010; Tue, 23 Sep 2025 13:49:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E1FAC8E0001; Tue, 23 Sep 2025 13:49:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CE8328E0010; Tue, 23 Sep 2025 13:49:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id B6A048E0001 for ; Tue, 23 Sep 2025 13:49:22 -0400 (EDT) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 7620613B499 for ; Tue, 23 Sep 2025 17:49:22 +0000 (UTC) X-FDA: 83921251764.25.95192DF Received: from PH7PR06CU001.outbound.protection.outlook.com (mail-westus3azon11010037.outbound.protection.outlook.com [52.101.201.37]) by imf09.hostedemail.com (Postfix) with ESMTP id 429BB14000A for ; Tue, 23 Sep 2025 17:49:18 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=bsp4l238; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf09.hostedemail.com: domain of shivankg@amd.com designates 52.101.201.37 as permitted sender) smtp.mailfrom=shivankg@amd.com; dmarc=pass (policy=quarantine) header.from=amd.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1758649759; 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-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=zF2Qac4zUCI7Q24GJOdmKjFI0FxBhpcs3iOGl7cRHs0=; b=e/5I7+/XwX781jS2U1aglUty9pog2QfpsN3m/ckjPcEn67ozrLJaPc5zgTq2rc5irfcmaE 1DwGlyBDrP+DSCwc4oRgUNN06BqzIbPahVCa3kZCwkUyk3eJ1a/r3wydh07euNvVeeYoY7 8V2pNkOh76bWltSTqY+WaZ3ZSwEIknQ= ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1758649759; a=rsa-sha256; cv=pass; b=MDhUx7DWt8ZznRMpznqEWv8HG9neXIOEJW16HoeGMXJJe34QJhYtWuG7k5ZNSKTafiHokW 76gcCXZFirV0vILgMrqEcK1ObMtu4545XSwZznXWRLeBujHym3MeMVMSAD4U+aFBz+BM2d x1J6DMncpKL/8m32qlU66VgHRKfkr/k= ARC-Authentication-Results: i=2; imf09.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=bsp4l238; arc=pass ("microsoft.com:s=arcselector10001:i=1"); spf=pass (imf09.hostedemail.com: domain of shivankg@amd.com designates 52.101.201.37 as permitted sender) smtp.mailfrom=shivankg@amd.com; dmarc=pass (policy=quarantine) header.from=amd.com ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=GiYmHo0esN+kPnRBIE9R23iaxhCTSoTViLHSevOoaOi+5iD6uEFGloKO3q4/Uyq4PoonzNeLQK8sjqYyGglUka0kPA4oq+djUoyrXbIUDhebg2RBJHy4USZBdWckVMHWVI3xzpzA4TnQzlkuacQjxwL6gXLgRMI8bUWHX2qW++yVvrrDBycJ1MfwZv5Z7qViRAH0NQq8pC01BYq6uU59hqeE9ZMPYWFZthPX4I7fUXv9caOjBw7B4kr8/uj5Oo8hTE264x3DXRYb++Jo+RgVEWYywayG4H4aKPqEgqEWAnoxAoE0P9i/9Ez6LEQomcaeTRv3CB1kYkJ/kzsv6N8ixg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=zF2Qac4zUCI7Q24GJOdmKjFI0FxBhpcs3iOGl7cRHs0=; b=woo0ZWx+KKF40kwGEqxawzw1HN4uHIZg/QRpE8xP3+7IbNoWnUJVV5ZNT6N07qJVEr3X97rOcw9OeCrgpVp/Aagayq0OKLPyeDObMgLliUgOSg4OqvVcMCaj3Vs/DFLQlxijr/smKRQmz3kCX68O+Y1OAeqYUiJRi914h8D83zK81OviD6gnIhMSMpagm8JFgh9gKAZukvnIQibRm9ZHbJvDc0h6wwTfMQb2QHE3fvzXOoS9nbLnLDe99t2YN9R3o0Gs4FOfkJDx1lVHO9nJHXzWaRLbX5eZ9QkpOhmBdSwJ+HQB23nj04ZkHP18ta0WqGv6LSYCAnldyIJJhP0Uqg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=linux-foundation.org smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none (0) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=zF2Qac4zUCI7Q24GJOdmKjFI0FxBhpcs3iOGl7cRHs0=; b=bsp4l238UDubzNFtznrq/V946YiBWakYFuQo44JiW/+UJgDVtRRlnA55KwDRP+5pOdgm6T9vDx+4v1iJsurNxAaz/pIK95yPS8EHTQ7hbjS5wI5uuP/StetosGjdpTXGCAIqXuDkpQhd93BlJUaqbq7ZrJ8JferKK5VtR6S5I4I= Received: from BL1P222CA0005.NAMP222.PROD.OUTLOOK.COM (2603:10b6:208:2c7::10) by DM4PR12MB5746.namprd12.prod.outlook.com (2603:10b6:8:5d::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9137.20; Tue, 23 Sep 2025 17:49:11 +0000 Received: from MN1PEPF0000F0E1.namprd04.prod.outlook.com (2603:10b6:208:2c7:cafe::9c) by BL1P222CA0005.outlook.office365.com (2603:10b6:208:2c7::10) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9137.20 via Frontend Transport; Tue, 23 Sep 2025 17:49:10 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by MN1PEPF0000F0E1.mail.protection.outlook.com (10.167.242.39) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9137.12 via Frontend Transport; Tue, 23 Sep 2025 17:49:10 +0000 Received: from kaveri.amd.com (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.17; Tue, 23 Sep 2025 10:48:56 -0700 From: Shivank Garg To: , CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [RFC V3 4/9] mm/migrate: add migrate_folios_batch_move to batch the folio move operations Date: Tue, 23 Sep 2025 17:47:39 +0000 Message-ID: <20250923174752.35701-5-shivankg@amd.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250923174752.35701-1-shivankg@amd.com> References: <20250923174752.35701-1-shivankg@amd.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: satlexmb07.amd.com (10.181.42.216) To satlexmb07.amd.com (10.181.42.216) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MN1PEPF0000F0E1:EE_|DM4PR12MB5746:EE_ X-MS-Office365-Filtering-Correlation-Id: 2bea6ddb-5773-4ef4-2555-08ddfac98070 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|36860700013|1800799024|7416014|376014|82310400026; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?KaKai3uP6nuNb1PEoRBCSLpbtqY1nMD+24k4jQECK23bJTjNtJ4N6UPUILtx?= =?us-ascii?Q?f7RXBghW1JLUzsfgZg77xRbh2m06owSQ3QiKxvZbG6yaJUQmcWNAHOKdcqIa?= =?us-ascii?Q?Y1olaYAxtr0ff0dSm1NvjCLMxmuAgMT+z56v3iQlHddAC3SSORXRYpjII52F?= =?us-ascii?Q?p52sw46qUyManZv6rIo30eSC49XHDj8FfZdQ5UHR2poDgi1U9pgYQGn0IjD9?= =?us-ascii?Q?Wwy/DvwR5UM2wbXSFBOwGB16RBukCZOj7z3SxYdQK/AQww0PDGt9xkeDJH+j?= =?us-ascii?Q?9Bp+wg5EXjlMfxFrvQaNUyKHieNJXXVw8APNbORNmghbjAAy5Y4GS2m3SW3t?= =?us-ascii?Q?PBFI968xBNUcKAVPTvs/aiViYwP2KNra64p9SjPHbM/ZsUUYA19VGXzMkX1H?= =?us-ascii?Q?rQuePgojalCq/hzV/PZHLAtChEzdgHQN3kiVPdN56LSg3z2A8pDCz8yd/yL7?= =?us-ascii?Q?rVO02CaahB6siLqnwt/FwR/xPE/nDKUcfjDuxwU7AQF8akx2spQoFPODC/mS?= =?us-ascii?Q?UGu8ewUWrSz1IFVvZaXqOD+HmhMQv1o1OS8aFEsclPPJDdLoLW9trUSwczZz?= =?us-ascii?Q?EkV3fYu+XZX2Ex9pm5Ce3lRsXVjCqJXNZT6C5U7efJq3tHA56Z0U3o/H6Ut7?= =?us-ascii?Q?dQJ6a1FKjW+PcqPfzTjVnX6z0eMWnZ8Nj3nUW4PwpTcZPBIwmXDINH93e0es?= =?us-ascii?Q?D2T2GYVcwusNhoK3F2uTe3m9wEdS7s+KjSM1ipjT0F/erDB0oZAZA7L1oqqa?= =?us-ascii?Q?+11AWQ2J4tWLxEHdHI+ubu98UqxVysWVhgAUEx8R+MRFD13wOA140o+gBha5?= =?us-ascii?Q?RmHl/BbBuvCbUKoSSJwydFrxSKJMDKI9MHe2PNdiQ6yNrqyxWanhMwdi+C/g?= =?us-ascii?Q?48FHvIGRtfhs+0av7vaIK9J8y9fscTKfdIB9K1lYxoRK2j26URXYpEC5zDNU?= =?us-ascii?Q?83fYn7c8gH06Cyf7FiXpaCBRz05NASqKSuWJoVgRSW8sZkMQqrtuGfUTKH9s?= =?us-ascii?Q?l8SD8oT2ps3X03hNMcJoNCRKjFaNVxr1blukE2vXjNClBcpI3S8uPgI1qPew?= =?us-ascii?Q?wGjV0RT/jrSoabdCCOV8nIdZ1ikR3h7S/EBCb2tgqciLrF7+bfNAga9JtZcH?= =?us-ascii?Q?FcsjdgnKOz7Cb5VLcKC/9wENYqUQFz9CPqAIyK8d0Lz5Ke4snhVsj3A8QEVP?= =?us-ascii?Q?5Kdv5sXgqZbUfLzwfUXvOeu06zpfnnlpfxeK4CjD+577qkXfsj4pd6Q1MJd/?= =?us-ascii?Q?VXPr5iuHowZ4on4pfutN5sA1XHIWyr5nlcwKr6u2+iAekKiek3LCjA3YzSu0?= =?us-ascii?Q?pK2z7TO2DcnnElifHBeNVtEQRGSDk0kuVIM4ZzQP7naSzJSTo4vSdpZhZzBf?= =?us-ascii?Q?ZMhFnehlj1iDJ5K3Rq4H110Jmb6WfymX1GndBnHO4YwclhIIlWXvN7QergS+?= =?us-ascii?Q?ycXrTGIMaI4EG+WpM2/6EnQJMOYbxOyLgRhpGVsGLn352iKwKesguRGyQKsa?= =?us-ascii?Q?5xclNhf8tpwJYrQzRpzVz2FEFJex0ULGQvRu?= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(36860700013)(1800799024)(7416014)(376014)(82310400026);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Sep 2025 17:49:10.6252 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 2bea6ddb-5773-4ef4-2555-08ddfac98070 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: MN1PEPF0000F0E1.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5746 X-Stat-Signature: 516ijip47pai163d4i4qbps6hudbn6a3 X-Rspamd-Queue-Id: 429BB14000A X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1758649758-137840 X-HE-Meta: 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 ynI1jYVh 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 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: This is a preparatory patch that enables batch copying for folios undergoing migration. By enabling batch copying the folio content, we can efficiently utilize the capabilities of DMA hardware or multi-threaded folio copy. It uses MIGRATE_NO_COPY to skip folio copy during metadata copy process and performed the copies in a batch later. Currently, the folio move operation is performed individually for each folio in sequential manner: for_each_folio() { Copy folio metadata like flags and mappings Copy the folio content from src to dst Update page tables with dst folio } With this patch, we transition to a batch processing approach as shown below: for_each_folio() { Copy folio metadata like flags and mappings } Batch copy all src folios to dst for_each_folio() { Update page tables with dst folios } dst->private is used to store page states and possible anon_vma value, thus needs to be cleared during metadata copy process. To avoid additional memory allocation to store the data during batch copy process, src->private is used to store the data after metadata copy process, since src is no longer used. Co-developed-by: Zi Yan Signed-off-by: Zi Yan Signed-off-by: Shivank Garg --- mm/migrate.c | 197 +++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 193 insertions(+), 4 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index 3fe78ecb146a..ce94e73a930d 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -843,12 +843,15 @@ static int __migrate_folio(struct address_space *mapping, struct folio *dst, enum migrate_mode mode) { int rc, expected_count = folio_expected_ref_count(src) + 1; + unsigned long dst_private = (unsigned long)dst->private; /* Check whether src does not have extra refs before we do more work */ if (folio_ref_count(src) != expected_count) return -EAGAIN; - if (mode != MIGRATE_NO_COPY) { + if (mode == MIGRATE_NO_COPY) { + dst->private = NULL; + } else { rc = folio_mc_copy(dst, src); if (unlikely(rc)) return rc; @@ -862,6 +865,10 @@ static int __migrate_folio(struct address_space *mapping, struct folio *dst, folio_attach_private(dst, folio_detach_private(src)); folio_migrate_flags(dst, src); + + if (mode == MIGRATE_NO_COPY) + src->private = (void *)dst_private; + return MIGRATEPAGE_SUCCESS; } @@ -1149,7 +1156,7 @@ static void __migrate_folio_record(struct folio *dst, dst->private = (void *)anon_vma + old_page_state; } -static void __migrate_folio_extract(struct folio *dst, +static void __migrate_folio_read(struct folio *dst, int *old_page_state, struct anon_vma **anon_vmap) { @@ -1157,6 +1164,12 @@ static void __migrate_folio_extract(struct folio *dst, *anon_vmap = (struct anon_vma *)(private & ~PAGE_OLD_STATES); *old_page_state = private & PAGE_OLD_STATES; +} +static void __migrate_folio_extract(struct folio *dst, + int *old_page_state, + struct anon_vma **anon_vmap) +{ + __migrate_folio_read(dst, old_page_state, anon_vmap); dst->private = NULL; } @@ -1776,6 +1789,176 @@ static void migrate_folios_move(struct list_head *src_folios, } } +static void migrate_folios_batch_move(struct list_head *src_folios, + struct list_head *dst_folios, + free_folio_t put_new_folio, unsigned long private, + enum migrate_mode mode, int reason, + struct list_head *ret_folios, + struct migrate_pages_stats *stats, + int *retry, int *thp_retry, int *nr_failed, + int *nr_retry_pages) +{ + struct folio *folio, *folio2, *dst, *dst2; + int rc, nr_pages = 0, nr_batched_folios = 0; + int old_page_state = 0; + struct anon_vma *anon_vma = NULL; + int is_thp = 0; + LIST_HEAD(err_src); + LIST_HEAD(err_dst); + + /* + * Iterate over the list of locked src/dst folios to copy the metadata + */ + dst = list_first_entry(dst_folios, struct folio, lru); + dst2 = list_next_entry(dst, lru); + list_for_each_entry_safe(folio, folio2, src_folios, lru) { + is_thp = folio_test_large(folio) && folio_test_pmd_mappable(folio); + nr_pages = folio_nr_pages(folio); + + /* + * dst->private is not cleared here. It is cleared and moved to + * src->private in __migrate_folio(). + */ + __migrate_folio_read(dst, &old_page_state, &anon_vma); + + /* + * Use MIGRATE_NO_COPY mode in migrate_folio family functions + * to copy the flags, mapping and some other ancillary information. + * This does everything except the page copy. The actual page copy + * is handled later in a batch manner. + */ + if (unlikely(page_movable_ops(&folio->page))) + rc = -EAGAIN; + else + rc = _move_to_new_folio_prep(dst, folio, MIGRATE_NO_COPY); + /* + * The rules are: + * Success: folio will be copied in batch + * -EAGAIN: move src/dst folios to tmp lists for + * non-batch retry + * Other errno: put src folio on ret_folios list, restore + * the dst folio + */ + if (rc == -EAGAIN) { + *retry += 1; + *thp_retry += is_thp; + *nr_retry_pages += nr_pages; + + list_move_tail(&folio->lru, &err_src); + list_move_tail(&dst->lru, &err_dst); + __migrate_folio_record(dst, old_page_state, anon_vma); + } else if (rc != MIGRATEPAGE_SUCCESS) { + *nr_failed += 1; + stats->nr_thp_failed += is_thp; + stats->nr_failed_pages += nr_pages; + + list_del(&dst->lru); + migrate_folio_undo_src(folio, + old_page_state & PAGE_WAS_MAPPED, + anon_vma, true, ret_folios); + migrate_folio_undo_dst(dst, true, put_new_folio, private); + } else { /* MIGRATEPAGE_SUCCESS */ + nr_batched_folios++; + } + + dst = dst2; + dst2 = list_next_entry(dst, lru); + } + + /* Exit if folio list for batch migration is empty */ + if (!nr_batched_folios) + goto out; + + /* Batch copy the folios */ + rc = folios_mc_copy(dst_folios, src_folios, nr_batched_folios); + + /* TODO: Is there a better way of handling the poison + * recover for batch copy, instead of falling back to serial copy? + */ + /* fallback to serial page copy if needed */ + if (rc) { + dst = list_first_entry(dst_folios, struct folio, lru); + dst2 = list_next_entry(dst, lru); + list_for_each_entry_safe(folio, folio2, src_folios, lru) { + is_thp = folio_test_large(folio) && + folio_test_pmd_mappable(folio); + nr_pages = folio_nr_pages(folio); + rc = folio_mc_copy(dst, folio); + + if (rc) { + /* + * dst->private is moved to src->private in + * __migrate_folio(), so page state and anon_vma + * values can be extracted from (src) folio. + */ + __migrate_folio_extract(folio, &old_page_state, + &anon_vma); + migrate_folio_undo_src(folio, + old_page_state & PAGE_WAS_MAPPED, + anon_vma, true, ret_folios); + list_del(&dst->lru); + migrate_folio_undo_dst(dst, true, put_new_folio, + private); + } + + switch (rc) { + case MIGRATEPAGE_SUCCESS: + stats->nr_succeeded += nr_pages; + stats->nr_thp_succeeded += is_thp; + break; + default: + *nr_failed += 1; + stats->nr_thp_failed += is_thp; + stats->nr_failed_pages += nr_pages; + break; + } + + dst = dst2; + dst2 = list_next_entry(dst, lru); + } + } + + /* + * Iterate the folio lists to remove migration pte and restore them + * as working pte. Unlock the folios, add/remove them to LRU lists (if + * applicable) and release the src folios. + */ + dst = list_first_entry(dst_folios, struct folio, lru); + dst2 = list_next_entry(dst, lru); + list_for_each_entry_safe(folio, folio2, src_folios, lru) { + is_thp = folio_test_large(folio) && folio_test_pmd_mappable(folio); + nr_pages = folio_nr_pages(folio); + /* + * dst->private is moved to src->private in __migrate_folio(), + * so page state and anon_vma values can be extracted from + * (src) folio. + */ + __migrate_folio_extract(folio, &old_page_state, &anon_vma); + list_del(&dst->lru); + + _move_to_new_folio_finalize(dst, folio, MIGRATEPAGE_SUCCESS); + + /* + * Below few steps are only applicable for lru pages which is + * ensured as we have removed the non-lru pages from our list. + */ + _migrate_folio_move_finalize1(folio, dst, old_page_state); + + _migrate_folio_move_finalize2(folio, dst, reason, anon_vma); + + /* Page migration successful, increase stat counter */ + stats->nr_succeeded += nr_pages; + stats->nr_thp_succeeded += is_thp; + + dst = dst2; + dst2 = list_next_entry(dst, lru); + } +out: + /* Add tmp folios back to the list to re-attempt migration. */ + list_splice(&err_src, src_folios); + list_splice(&err_dst, dst_folios); +} + static void migrate_folios_undo(struct list_head *src_folios, struct list_head *dst_folios, free_folio_t put_new_folio, unsigned long private, @@ -1986,13 +2169,19 @@ static int migrate_pages_batch(struct list_head *from, /* Flush TLBs for all unmapped folios */ try_to_unmap_flush(); - retry = 1; + retry = 0; + /* Batch move the unmapped folios */ + migrate_folios_batch_move(&unmap_folios, &dst_folios, + put_new_folio, private, mode, reason, + ret_folios, stats, &retry, &thp_retry, + &nr_failed, &nr_retry_pages); + for (pass = 0; pass < nr_pass && retry; pass++) { retry = 0; thp_retry = 0; nr_retry_pages = 0; - /* Move the unmapped folios */ + /* Move the remaining unmapped folios */ migrate_folios_move(&unmap_folios, &dst_folios, put_new_folio, private, mode, reason, ret_folios, stats, &retry, &thp_retry, -- 2.43.0