From patchwork Sun Dec 15 07:49:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ge Yang X-Patchwork-Id: 13908678 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]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90E31E7716A for ; Sun, 15 Dec 2024 07:50:17 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1F8046B0083; Sun, 15 Dec 2024 02:50:17 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1A7EF6B008A; Sun, 15 Dec 2024 02:50:17 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0487B6B008C; Sun, 15 Dec 2024 02:50:16 -0500 (EST) 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 D68786B0083 for ; Sun, 15 Dec 2024 02:50:16 -0500 (EST) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 8A21DA2A39 for ; Sun, 15 Dec 2024 07:50:16 +0000 (UTC) X-FDA: 82896419760.15.001181C Received: from m16.mail.126.com (m16.mail.126.com [117.135.210.7]) by imf03.hostedemail.com (Postfix) with ESMTP id 1A83F20008 for ; Sun, 15 Dec 2024 07:50:00 +0000 (UTC) Authentication-Results: imf03.hostedemail.com; dkim=pass header.d=126.com header.s=s110527 header.b=l2W0znZA; spf=pass (imf03.hostedemail.com: domain of yangge1116@126.com designates 117.135.210.7 as permitted sender) smtp.mailfrom=yangge1116@126.com; dmarc=pass (policy=none) header.from=126.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1734249002; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references:dkim-signature; bh=8B9OUvtPr5d/VfK1XKdfdxp6TD6ZA+UFEFSi2o2Q+Ok=; b=mgoivNJ8ZmU9IG8JCIDhiZWMDm9rtbtuykJGR8HvBebfdvl2JV56TPpzatmg3MeYm1bLRz PDmmJVYaETQHwfytRe95fo4q3HMMcZan9/WZXTen1VmIj7DLR417rrzXR1e/aUw6BFzVFR 3iSB0rA/WqJLVvMcpk0to0vujYqXTt0= ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=pass header.d=126.com header.s=s110527 header.b=l2W0znZA; spf=pass (imf03.hostedemail.com: domain of yangge1116@126.com designates 117.135.210.7 as permitted sender) smtp.mailfrom=yangge1116@126.com; dmarc=pass (policy=none) header.from=126.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1734249002; a=rsa-sha256; cv=none; b=E2/7h9wsm2iLNeux7PuCuAKGnTc3RZau7vB2tKSYY2ZvZt0/EmZuGf8TKwcWkc0CGvOINh 85spY6PPkvYE9IPakU1FElsBFC2Bsh6veGdbDPieIhOOhXwUPajmv/DAud00f3ZGJLjIJR ZjFjwzDavdoI6FekKlXZoVF3p8TaokE= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=126.com; s=s110527; h=From:Subject:Date:Message-Id; bh=8B9OUvtPr5d/VfK1XK dfdxp6TD6ZA+UFEFSi2o2Q+Ok=; b=l2W0znZAHDqyqeV5R6rUPowK9qHle0d9Sr 26OHONDhWZV/MzSZKnf76E5YAYnZCXFnR9QxAA5jcLL1y5TM/yUuWmCPAQF3J5Lo FN7aME0JAyRc9U4uvWHlh55HpnqQzcf8KPSHJB14JQRghjsEgHKe5eEOvxQKS3bK HOD7cXM3w= Received: from hg-OptiPlex-7040.hygon.cn (unknown []) by gzga-smtp-mtada-g0-3 (Coremail) with SMTP id _____wDX720pil5nJIfQAQ--.4292S2; Sun, 15 Dec 2024 15:50:03 +0800 (CST) From: yangge1116@126.com To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, 21cnbao@gmail.com, david@redhat.com, baolin.wang@linux.alibaba.com, vbabka@suse.cz, liuzixing@hygon.cn, yangge Subject: [PATCH V3] mm, compaction: don't use ALLOC_CMA in long term GUP flow Date: Sun, 15 Dec 2024 15:49:52 +0800 Message-Id: <1734248992-17701-1-git-send-email-yangge1116@126.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: _____wDX720pil5nJIfQAQ--.4292S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxtry8Zr4kJry8uFykWrWruFg_yoWxtF1fpF 18Za4jy395XF13GrW8tF409a1Yqw4xGF18JryIgw1xZw1akFn2v3WkKFy7AF15Xry5AF4Y qFWq9ryDCFsxAFJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zPw3UUUUUUU= X-Originating-IP: [118.242.3.34] X-CM-SenderInfo: 51dqwwjhrrila6rslhhfrp/1tbiWRW2G2deaOULUgABsN X-Rspamd-Queue-Id: 1A83F20008 X-Stat-Signature: hkp93kka1zxufa9azfahr3syygdtybka X-Rspam-User: X-Rspamd-Server: rspam11 X-HE-Tag: 1734249000-492483 X-HE-Meta: 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 lBZlYShg nkDxqoiV6HjhngGfD31CEKyj0BtUTrSKzBruX9n5+2adYCuS69iqbFdmc2osFYgPmM3l9pMRFFFaq7rdbIBLkRpGxfRRE/ltzbXqxYHSUcVHvbZfZLUyQbxEKVvCqYNcO2WTtM9zuP+F8Zypn8VBIJWOHwbB7Uau9jEM/DD3TLGp7slfjqrFuTvONfpvSrItRhxkhgdp+OfGRUGuqoCvadoZIWQi9UniS95bnSL/zs9I1UjlwZ7fYeZgN3+Oiluhg86OG96NV1MhwiRxWgZPNYcT6MJuqks1+Ic2gO5vBVzTyuxrVmxYKc3zcBrqMjZSLwbVb 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: From: yangge Since commit 984fdba6a32e ("mm, compaction: use proper alloc_flags in __compaction_suitable()") allow compaction to proceed when free pages required for compaction reside in the CMA pageblocks, it's possible that __compaction_suitable() always returns true, and in some cases, it's not acceptable. There are 4 NUMA nodes on my machine, and each NUMA node has 32GB of memory. I have configured 16GB of CMA memory on each NUMA node, and starting a 32GB virtual machine with device passthrough is extremely slow, taking almost an hour. During the start-up of the virtual machine, it will call pin_user_pages_remote(..., FOLL_LONGTERM, ...) to allocate memory. Long term GUP cannot allocate memory from CMA area, so a maximum of 16 GB of no-CMA memory on a NUMA node can be used as virtual machine memory. Since there is 16G of free CMA memory on the NUMA node, watermark for order-0 always be met for compaction, so __compaction_suitable() always returns true, even if the node is unable to allocate non-CMA memory for the virtual machine. For costly allocations, because __compaction_suitable() always returns true, __alloc_pages_slowpath() can't exit at the appropriate place, resulting in excessively long virtual machine startup times. Call trace: __alloc_pages_slowpath if (compact_result == COMPACT_SKIPPED || compact_result == COMPACT_DEFERRED) goto nopage; // should exit __alloc_pages_slowpath() from here To sum up, during long term GUP flow, we should remove ALLOC_CMA both in __compaction_suitable() and __isolate_free_page(). Signed-off-by: yangge --- V3: - fix build errors - add ALLOC_CMA both in should_continue_reclaim() and compaction_ready() V2: - using the 'cc->alloc_flags' to determin if 'ALLOC_CMA' is needed - rich the commit log description include/linux/compaction.h | 6 ++++-- mm/compaction.c | 18 +++++++++++------- mm/page_alloc.c | 4 +++- mm/vmscan.c | 4 ++-- 4 files changed, 20 insertions(+), 12 deletions(-) diff --git a/include/linux/compaction.h b/include/linux/compaction.h index e947764..b4c3ac3 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -90,7 +90,8 @@ extern enum compact_result try_to_compact_pages(gfp_t gfp_mask, struct page **page); extern void reset_isolation_suitable(pg_data_t *pgdat); extern bool compaction_suitable(struct zone *zone, int order, - int highest_zoneidx); + int highest_zoneidx, + unsigned int alloc_flags); extern void compaction_defer_reset(struct zone *zone, int order, bool alloc_success); @@ -108,7 +109,8 @@ static inline void reset_isolation_suitable(pg_data_t *pgdat) } static inline bool compaction_suitable(struct zone *zone, int order, - int highest_zoneidx) + int highest_zoneidx, + unsigned int alloc_flags) { return false; } diff --git a/mm/compaction.c b/mm/compaction.c index 07bd227..585f5ab 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -2381,9 +2381,11 @@ static enum compact_result compact_finished(struct compact_control *cc) static bool __compaction_suitable(struct zone *zone, int order, int highest_zoneidx, + unsigned int alloc_flags, unsigned long wmark_target) { unsigned long watermark; + bool use_cma; /* * Watermarks for order-0 must be met for compaction to be able to * isolate free pages for migration targets. This means that the @@ -2395,25 +2397,27 @@ static bool __compaction_suitable(struct zone *zone, int order, * even if compaction succeeds. * For costly orders, we require low watermark instead of min for * compaction to proceed to increase its chances. - * ALLOC_CMA is used, as pages in CMA pageblocks are considered - * suitable migration targets + * In addition to long term GUP flow, ALLOC_CMA is used, as pages in + * CMA pageblocks are considered suitable migration targets */ watermark = (order > PAGE_ALLOC_COSTLY_ORDER) ? low_wmark_pages(zone) : min_wmark_pages(zone); watermark += compact_gap(order); + use_cma = !!(alloc_flags & ALLOC_CMA); return __zone_watermark_ok(zone, 0, watermark, highest_zoneidx, - ALLOC_CMA, wmark_target); + use_cma ? ALLOC_CMA : 0, wmark_target); } /* * compaction_suitable: Is this suitable to run compaction on this zone now? */ -bool compaction_suitable(struct zone *zone, int order, int highest_zoneidx) +bool compaction_suitable(struct zone *zone, int order, int highest_zoneidx, + unsigned int alloc_flags) { enum compact_result compact_result; bool suitable; - suitable = __compaction_suitable(zone, order, highest_zoneidx, + suitable = __compaction_suitable(zone, order, highest_zoneidx, alloc_flags, zone_page_state(zone, NR_FREE_PAGES)); /* * fragmentation index determines if allocation failures are due to @@ -2474,7 +2478,7 @@ bool compaction_zonelist_suitable(struct alloc_context *ac, int order, available = zone_reclaimable_pages(zone) / order; available += zone_page_state_snapshot(zone, NR_FREE_PAGES); if (__compaction_suitable(zone, order, ac->highest_zoneidx, - available)) + alloc_flags, available)) return true; } @@ -2499,7 +2503,7 @@ compaction_suit_allocation_order(struct zone *zone, unsigned int order, alloc_flags)) return COMPACT_SUCCESS; - if (!compaction_suitable(zone, order, highest_zoneidx)) + if (!compaction_suitable(zone, order, highest_zoneidx, alloc_flags)) return COMPACT_SKIPPED; return COMPACT_CONTINUE; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index dde19db..9a5dfda 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2813,6 +2813,7 @@ int __isolate_free_page(struct page *page, unsigned int order) { struct zone *zone = page_zone(page); int mt = get_pageblock_migratetype(page); + bool pin; if (!is_migrate_isolate(mt)) { unsigned long watermark; @@ -2823,7 +2824,8 @@ int __isolate_free_page(struct page *page, unsigned int order) * exists. */ watermark = zone->_watermark[WMARK_MIN] + (1UL << order); - if (!zone_watermark_ok(zone, 0, watermark, 0, ALLOC_CMA)) + pin = !!(current->flags & PF_MEMALLOC_PIN); + if (!zone_watermark_ok(zone, 0, watermark, 0, pin ? 0 : ALLOC_CMA)) return 0; } diff --git a/mm/vmscan.c b/mm/vmscan.c index 5e03a61..33f5b46 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -5815,7 +5815,7 @@ static inline bool should_continue_reclaim(struct pglist_data *pgdat, sc->reclaim_idx, 0)) return false; - if (compaction_suitable(zone, sc->order, sc->reclaim_idx)) + if (compaction_suitable(zone, sc->order, sc->reclaim_idx, ALLOC_CMA)) return false; } @@ -6043,7 +6043,7 @@ static inline bool compaction_ready(struct zone *zone, struct scan_control *sc) return true; /* Compaction cannot yet proceed. Do reclaim. */ - if (!compaction_suitable(zone, sc->order, sc->reclaim_idx)) + if (!compaction_suitable(zone, sc->order, sc->reclaim_idx, ALLOC_CMA)) return false; /*