From patchwork Sun Oct 11 06:16:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 270404 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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 91697C433DF for ; Sun, 11 Oct 2020 06:16:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A058207FB for ; Sun, 11 Oct 2020 06:16:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602397004; bh=IyqHAWRPBL2RMcqOEsEI5dcoZxecQpW7RFZwHcG2Dgs=; h=Date:From:To:Subject:In-Reply-To:List-ID:From; b=fw2LKNy6ohZ4fgZ+CsbbUB7kIxvsIxweVRxz4UUaUdA1MPmH78i4TMBuHgD4PH2mV 5eYiUfOIswnCdnTCMLko0gqaW0S0K0pfYxPpn5d3KGHrTrLFsCNRGL2RPjZuEhiXsJ 61Sb0+V5S64PEhoAULJuKTLuClmQ4JvcvuKXGrW4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726677AbgJKGQn (ORCPT ); Sun, 11 Oct 2020 02:16:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:47680 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725882AbgJKGQn (ORCPT ); Sun, 11 Oct 2020 02:16:43 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4174620795; Sun, 11 Oct 2020 06:16:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602397001; bh=IyqHAWRPBL2RMcqOEsEI5dcoZxecQpW7RFZwHcG2Dgs=; h=Date:From:To:Subject:In-Reply-To:From; b=K2iozGenW53RqucP6YFUnK8jRsplREkPTQfHjG7JG58hCt163filqD+TqfEiUQsAD Tf+LLbJC17wls/+D/ohOoC3NGpdt/JNDczV+79S0/2lttqVz4bHalttwMdJNrJWNRL RvVn9zSAySChiCcAyQeHPliX/BG/PKSABEvr/Zzg= Date: Sat, 10 Oct 2020 23:16:40 -0700 From: Andrew Morton To: aarcange@redhat.com, akpm@linux-foundation.org, apais@microsoft.com, kirill.shutemov@linux.intel.com, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, oleg@redhat.com, pasha.tatashin@soleen.com, songliubraving@fb.com, stable@vger.kernel.org, torvalds@linux-foundation.org, vijayb@linux.microsoft.com Subject: [patch 5/5] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Message-ID: <20201011061640.f9YRgiyXB%akpm@linux-foundation.org> In-Reply-To: <20201010231559.e148a66f744d0b4870301450@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vijay Balakrishna Subject: mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged When memory is hotplug added or removed the min_free_kbytes should be recalculated based on what is expected by khugepaged. Currently after hotplug, min_free_kbytes will be set to a lower default and higher default set when THP enabled is lost. This change restores min_free_kbytes as expected for THP consumers. [vijayb@linux.microsoft.com: v5] Link: https://lkml.kernel.org/r/1601398153-5517-1-git-send-email-vijayb@linux.microsoft.com Link: https://lkml.kernel.org/r/1600305709-2319-2-git-send-email-vijayb@linux.microsoft.com Link: https://lkml.kernel.org/r/1600204258-13683-1-git-send-email-vijayb@linux.microsoft.com Fixes: f000565adb77 ("thp: set recommended min free kbytes") Signed-off-by: Vijay Balakrishna Reviewed-by: Pavel Tatashin Acked-by: Michal Hocko Cc: Allen Pais Cc: Andrea Arcangeli Cc: "Kirill A. Shutemov" Cc: Oleg Nesterov Cc: Song Liu Cc: Signed-off-by: Andrew Morton --- include/linux/khugepaged.h | 5 +++++ mm/khugepaged.c | 13 +++++++++++-- mm/page_alloc.c | 3 +++ 3 files changed, 19 insertions(+), 2 deletions(-) --- a/include/linux/khugepaged.h~mm-khugepaged-recalculate-min_free_kbytes-after-memory-hotplug-as-expected-by-khugepaged +++ a/include/linux/khugepaged.h @@ -15,6 +15,7 @@ extern int __khugepaged_enter(struct mm_ extern void __khugepaged_exit(struct mm_struct *mm); extern int khugepaged_enter_vma_merge(struct vm_area_struct *vma, unsigned long vm_flags); +extern void khugepaged_min_free_kbytes_update(void); #ifdef CONFIG_SHMEM extern void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr); #else @@ -85,6 +86,10 @@ static inline void collapse_pte_mapped_t unsigned long addr) { } + +static inline void khugepaged_min_free_kbytes_update(void) +{ +} #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif /* _LINUX_KHUGEPAGED_H */ --- a/mm/khugepaged.c~mm-khugepaged-recalculate-min_free_kbytes-after-memory-hotplug-as-expected-by-khugepaged +++ a/mm/khugepaged.c @@ -56,6 +56,9 @@ enum scan_result { #define CREATE_TRACE_POINTS #include +static struct task_struct *khugepaged_thread __read_mostly; +static DEFINE_MUTEX(khugepaged_mutex); + /* default scan 8*512 pte (or vmas) every 30 second */ static unsigned int khugepaged_pages_to_scan __read_mostly; static unsigned int khugepaged_pages_collapsed; @@ -2304,8 +2307,6 @@ static void set_recommended_min_free_kby int start_stop_khugepaged(void) { - static struct task_struct *khugepaged_thread __read_mostly; - static DEFINE_MUTEX(khugepaged_mutex); int err = 0; mutex_lock(&khugepaged_mutex); @@ -2332,3 +2333,11 @@ fail: mutex_unlock(&khugepaged_mutex); return err; } + +void khugepaged_min_free_kbytes_update(void) +{ + mutex_lock(&khugepaged_mutex); + if (khugepaged_enabled() && khugepaged_thread) + set_recommended_min_free_kbytes(); + mutex_unlock(&khugepaged_mutex); +} --- a/mm/page_alloc.c~mm-khugepaged-recalculate-min_free_kbytes-after-memory-hotplug-as-expected-by-khugepaged +++ a/mm/page_alloc.c @@ -69,6 +69,7 @@ #include #include #include +#include #include #include @@ -7904,6 +7905,8 @@ int __meminit init_per_zone_wmark_min(vo setup_min_slab_ratio(); #endif + khugepaged_min_free_kbytes_update(); + return 0; } postcore_initcall(init_per_zone_wmark_min)