From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 025/166] mm: add function __putback_isolated_page Date: Mon, 06 Apr 2020 20:04:53 -0700 Message-ID: <20200407030453.wHtLS1Hh4%akpm@linux-foundation.org> References: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:48866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726331AbgDGDEz (ORCPT ); Mon, 6 Apr 2020 23:04:55 -0400 In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: aarcange@redhat.com, akpm@linux-foundation.org, alexander.h.duyck@linux.intel.com, dan.j.williams@intel.com, dave.hansen@intel.com, david@redhat.com, konrad.wilk@oracle.com, lcapitulino@redhat.com, linux-mm@kvack.org, mgorman@techsingularity.net, mhocko@kernel.org, mm-commits@vger.kernel.org, mst@redhat.com, nitesh@redhat.com, osalvador@suse.de, pagupta@redhat.com, pbonzini@redhat.com, riel@surriel.com, torvalds@linux-foundation.org, vbabka@suse.cz, wei.w.wang@intel.com, weiqi4@huawei.com, willy@infradead.org, yang.zhang.wz@gmail.com From: Alexander Duyck Subject: mm: add function __putback_isolated_page There are cases where we would benefit from avoiding having to go through the allocation and free cycle to return an isolated page. Examples for this might include page poisoning in which we isolate a page and then put it back in the free list without ever having actually allocated it. This will enable us to also avoid notifiers for the future free page reporting which will need to avoid retriggering page reporting when returning pages that have been reported on. Link: http://lkml.kernel.org/r/20200211224624.29318.89287.stgit@localhost.localdomain Signed-off-by: Alexander Duyck Acked-by: David Hildenbrand Acked-by: Mel Gorman Cc: Andrea Arcangeli Cc: Dan Williams Cc: Dave Hansen Cc: Konrad Rzeszutek Wilk Cc: Luiz Capitulino Cc: Matthew Wilcox Cc: Michael S. Tsirkin Cc: Michal Hocko Cc: Nitesh Narayan Lal Cc: Oscar Salvador Cc: Pankaj Gupta Cc: Paolo Bonzini Cc: Rik van Riel Cc: Vlastimil Babka Cc: Wei Wang Cc: Yang Zhang Cc: wei qi Signed-off-by: Andrew Morton --- mm/internal.h | 2 ++ mm/page_alloc.c | 19 +++++++++++++++++++ mm/page_isolation.c | 6 ++---- 3 files changed, 23 insertions(+), 4 deletions(-) --- a/mm/internal.h~mm-add-function-__putback_isolated_page +++ a/mm/internal.h @@ -180,6 +180,8 @@ static inline struct page *pageblock_pfn } extern int __isolate_free_page(struct page *page, unsigned int order); +extern void __putback_isolated_page(struct page *page, unsigned int order, + int mt); extern void memblock_free_pages(struct page *page, unsigned long pfn, unsigned int order); extern void __free_pages_core(struct page *page, unsigned int order); --- a/mm/page_alloc.c~mm-add-function-__putback_isolated_page +++ a/mm/page_alloc.c @@ -3211,6 +3211,25 @@ int __isolate_free_page(struct page *pag return 1UL << order; } +/** + * __putback_isolated_page - Return a now-isolated page back where we got it + * @page: Page that was isolated + * @order: Order of the isolated page + * + * This function is meant to return a page pulled from the free lists via + * __isolate_free_page back to the free lists they were pulled from. + */ +void __putback_isolated_page(struct page *page, unsigned int order, int mt) +{ + struct zone *zone = page_zone(page); + + /* zone lock should be held when this function is called */ + lockdep_assert_held(&zone->lock); + + /* Return isolated page to tail of freelist. */ + __free_one_page(page, page_to_pfn(page), zone, order, mt); +} + /* * Update NUMA hit/miss statistics * --- a/mm/page_isolation.c~mm-add-function-__putback_isolated_page +++ a/mm/page_isolation.c @@ -117,13 +117,11 @@ static void unset_migratetype_isolate(st __mod_zone_freepage_state(zone, nr_pages, migratetype); } set_pageblock_migratetype(page, migratetype); + if (isolated_page) + __putback_isolated_page(page, order, migratetype); zone->nr_isolate_pageblock--; out: spin_unlock_irqrestore(&zone->lock, flags); - if (isolated_page) { - post_alloc_hook(page, order, __GFP_MOVABLE); - __free_pages(page, order); - } } static inline struct page * _