From patchwork Tue Nov 24 19:49:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rik van Riel X-Patchwork-Id: 11929787 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 3B474C63777 for ; Tue, 24 Nov 2020 19:49:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B98F3208CA for ; Tue, 24 Nov 2020 19:49:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B98F3208CA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=surriel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4EFD46B0072; Tue, 24 Nov 2020 14:49:44 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 47BDA6B0073; Tue, 24 Nov 2020 14:49:44 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2335A6B0074; Tue, 24 Nov 2020 14:49:44 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0084.hostedemail.com [216.40.44.84]) by kanga.kvack.org (Postfix) with ESMTP id 057BD6B0072 for ; Tue, 24 Nov 2020 14:49:44 -0500 (EST) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id C0C1E181AEF2A for ; Tue, 24 Nov 2020 19:49:43 +0000 (UTC) X-FDA: 77520351846.07.limit15_5f0bd8827370 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin07.hostedemail.com (Postfix) with ESMTP id 9FA981803F9AB for ; Tue, 24 Nov 2020 19:49:43 +0000 (UTC) X-HE-Tag: limit15_5f0bd8827370 X-Filterd-Recvd-Size: 5360 Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) by imf24.hostedemail.com (Postfix) with ESMTP for ; Tue, 24 Nov 2020 19:49:43 +0000 (UTC) Received: from imladris.surriel.com ([96.67.55.152]) by shelob.surriel.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1kheJc-0006wM-1r; Tue, 24 Nov 2020 14:49:28 -0500 From: Rik van Riel To: hughd@google.com Cc: xuyu@linux.alibaba.com, akpm@linux-foundation.org, mgorman@suse.de, aarcange@redhat.com, willy@infradead.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, linux-mm@kvack.org, vbabka@suse.cz, mhocko@suse.com, Rik van Riel Subject: [PATCH 1/3] mm,thp,shmem: limit shmem THP alloc gfp_mask Date: Tue, 24 Nov 2020 14:49:23 -0500 Message-Id: <20201124194925.623931-2-riel@surriel.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20201124194925.623931-1-riel@surriel.com> References: <20201124194925.623931-1-riel@surriel.com> MIME-Version: 1.0 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: The allocation flags of anonymous transparent huge pages can be controlled through the files in /sys/kernel/mm/transparent_hugepage/defrag, which can help the system from getting bogged down in the page reclaim and compaction code when many THPs are getting allocated simultaneously. However, the gfp_mask for shmem THP allocations were not limited by those configuration settings, and some workloads ended up with all CPUs stuck on the LRU lock in the page reclaim code, trying to allocate dozens of THPs simultaneously. This patch applies the same configurated limitation of THPs to shmem hugepage allocations, to prevent that from happening. Controlling the gfp_mask of THP allocations through the knobs in sysfs allows users to determine the balance between how aggressively the system tries to allocate THPs at fault time, and how much the application may end up stalling attempting those allocations. This way a THP defrag setting of "never" or "defer+madvise" will result in quick allocation failures without direct reclaim when no 2MB free pages are available. With this patch applied, THP allocations for tmpfs will be a little more aggressive than today for files mmapped with MADV_HUGEPAGE, and a little less aggressive for files that are not mmapped or mapped without that flag. Signed-off-by: Rik van Riel Acked-by: Vlastimil Babka Acked-by: Michal Hocko --- include/linux/gfp.h | 2 ++ mm/huge_memory.c | 6 +++--- mm/shmem.c | 8 +++++--- 3 files changed, 10 insertions(+), 6 deletions(-) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index c603237e006c..c7615c9ba03c 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -614,6 +614,8 @@ bool gfp_pfmemalloc_allowed(gfp_t gfp_mask); extern void pm_restrict_gfp_mask(void); extern void pm_restore_gfp_mask(void); +extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma); + #ifdef CONFIG_PM_SLEEP extern bool pm_suspended_storage(void); #else diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 9474dbc150ed..c5d03b2f2f2f 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -649,9 +649,9 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, * available * never: never stall for any thp allocation */ -static inline gfp_t alloc_hugepage_direct_gfpmask(struct vm_area_struct *vma) +gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma) { - const bool vma_madvised = !!(vma->vm_flags & VM_HUGEPAGE); + const bool vma_madvised = vma && (vma->vm_flags & VM_HUGEPAGE); /* Always do synchronous compaction */ if (test_bit(TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, &transparent_hugepage_flags)) @@ -744,7 +744,7 @@ vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf) pte_free(vma->vm_mm, pgtable); return ret; } - gfp = alloc_hugepage_direct_gfpmask(vma); + gfp = vma_thp_gfp_mask(vma); page = alloc_hugepage_vma(gfp, vma, haddr, HPAGE_PMD_ORDER); if (unlikely(!page)) { count_vm_event(THP_FAULT_FALLBACK); diff --git a/mm/shmem.c b/mm/shmem.c index 537c137698f8..6c3cb192a88d 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1545,8 +1545,8 @@ static struct page *shmem_alloc_hugepage(gfp_t gfp, return NULL; shmem_pseudo_vma_init(&pvma, info, hindex); - page = alloc_pages_vma(gfp | __GFP_COMP | __GFP_NORETRY | __GFP_NOWARN, - HPAGE_PMD_ORDER, &pvma, 0, numa_node_id(), true); + page = alloc_pages_vma(gfp, HPAGE_PMD_ORDER, &pvma, 0, numa_node_id(), + true); shmem_pseudo_vma_destroy(&pvma); if (page) prep_transhuge_page(page); @@ -1802,6 +1802,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, struct page *page; enum sgp_type sgp_huge = sgp; pgoff_t hindex = index; + gfp_t huge_gfp; int error; int once = 0; int alloced = 0; @@ -1887,7 +1888,8 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, } alloc_huge: - page = shmem_alloc_and_acct_page(gfp, inode, index, true); + huge_gfp = vma_thp_gfp_mask(vma); + page = shmem_alloc_and_acct_page(huge_gfp, inode, index, true); if (IS_ERR(page)) { alloc_nohuge: page = shmem_alloc_and_acct_page(gfp, inode,