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 24A28C25B08 for ; Wed, 17 Aug 2022 08:16:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235410AbiHQIPX (ORCPT ); Wed, 17 Aug 2022 04:15:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234662AbiHQIOw (ORCPT ); Wed, 17 Aug 2022 04:14:52 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4F286B175 for ; Wed, 17 Aug 2022 01:14:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1660724076; x=1692260076; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=hLXpcVQ48bukYRKZHdLPgeEwQ0PlwBGDjboqajk5r+E=; b=HID/2V1EIYGF7Uh+e2/sgeBU/jbL5iqqLgvP6uuE1YLsaMyy0dJbiVgV 40obBbPaPLqiy9+u85RZ43YhYNnS6Y8Z06y6LhuzrNDLmRSdeU7VnptvC CkiFEh4IYY7dzH6kdzsTv6GyrdIHn/17QmrIgChVSCDh/JodN+GQQYaeV sbZQZYuVdEfG+e8yXasXPnLMwymbybx5JuN/vVKAT2MDA3QwcLa7bGWWl VSe6VLN2FCHiVugyW2MzsT/SEWTC0gqlLaW+rclwAuNLeiyEr4Hw0+Gbo FhowMdZPBekkUFbY4abq2mxkCxXX7YevyrHJZJYaG+P62EFstK+62SfZe A==; X-IronPort-AV: E=McAfee;i="6400,9594,10441"; a="293228842" X-IronPort-AV: E=Sophos;i="5.93,242,1654585200"; d="scan'208";a="293228842" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2022 01:14:36 -0700 X-IronPort-AV: E=Sophos;i="5.93,242,1654585200"; d="scan'208";a="583668137" Received: from yhuang6-mobl1.sh.intel.com ([10.238.6.172]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2022 01:14:32 -0700 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Baolin Wang , Oscar Salvador , Zi Yan , Yang Shi Subject: [PATCH -V3 6/8] migrate_pages(): fix failure counting for THP splitting Date: Wed, 17 Aug 2022 16:14:06 +0800 Message-Id: <20220817081408.513338-7-ying.huang@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220817081408.513338-1-ying.huang@intel.com> References: <20220817081408.513338-1-ying.huang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If THP is failed to be migrated, it may be split and retry. But after splitting, the head page will be left in "from" list, although THP migration failure has been counted already. If the head page is failed to be migrated too, the failure will be counted twice incorrectly. So this is fixed in this patch via moving the head page of THP after splitting to "thp_split_pages" too. Signed-off-by: "Huang, Ying" Fixes: 5984fabb6e82 ("mm: move_pages: report the number of non-attempted pages") Reviewed-by: Baolin Wang Reviewed-by: Oscar Salvador Cc: Zi Yan Cc: Yang Shi --- mm/migrate.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index 0223673e42d1..81daa4dd3bb6 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1374,6 +1374,8 @@ static inline int try_split_thp(struct page *page, struct list_head *split_pages lock_page(page); rc = split_huge_page_to_list(page, split_pages); unlock_page(page); + if (!rc) + list_move_tail(&page->lru, split_pages); return rc; } @@ -1433,7 +1435,6 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, thp_retry = 0; list_for_each_entry_safe(page, page2, from, lru) { -retry: /* * THP statistics is based on the source huge page. * Capture required information that might get lost @@ -1469,10 +1470,9 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, * retry on the same page with the THP split * to base pages. * - * Head page is retried immediately and tail - * pages are added to the tail of the list so - * we encounter them after the rest of the list - * is processed. + * Sub-pages are put in thp_split_pages, and + * we will migrate them after the rest of the + * list is processed. */ case -ENOSYS: /* THP migration is unsupported */ @@ -1480,7 +1480,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, nr_thp_failed++; if (!try_split_thp(page, &thp_split_pages)) { nr_thp_split++; - goto retry; + break; } /* Hugetlb migration is unsupported */ } else if (!no_subpage_counting) { @@ -1500,7 +1500,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, /* THP NUMA faulting doesn't split THP to retry. */ if (!nosplit && !try_split_thp(page, &thp_split_pages)) { nr_thp_split++; - goto retry; + break; } } else if (!no_subpage_counting) { nr_failed++; -- 2.30.2