From patchwork Tue Nov 29 15:17:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mel Gorman X-Patchwork-Id: 13058712 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 A90B2C4167B for ; Tue, 29 Nov 2022 15:18:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 53D5B6B007B; Tue, 29 Nov 2022 10:18:10 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 4C5876B007D; Tue, 29 Nov 2022 10:18:10 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 38D976B007E; Tue, 29 Nov 2022 10:18:10 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 24E996B007B for ; Tue, 29 Nov 2022 10:18:10 -0500 (EST) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 9C584AB6FF for ; Tue, 29 Nov 2022 15:18:09 +0000 (UTC) X-FDA: 80186835498.30.005FE4F Received: from outbound-smtp29.blacknight.com (outbound-smtp29.blacknight.com [81.17.249.32]) by imf24.hostedemail.com (Postfix) with ESMTP id 336F818001A for ; Tue, 29 Nov 2022 15:18:06 +0000 (UTC) Received: from mail.blacknight.com (pemlinmail02.blacknight.ie [81.17.254.11]) by outbound-smtp29.blacknight.com (Postfix) with ESMTPS id C73BDBEC7F for ; Tue, 29 Nov 2022 15:18:05 +0000 (GMT) Received: (qmail 5862 invoked from network); 29 Nov 2022 15:18:05 -0000 Received: from unknown (HELO morpheus.112glenside.lan) (mgorman@techsingularity.net@[84.203.198.246]) by 81.17.254.9 with ESMTPA; 29 Nov 2022 15:18:05 -0000 From: Mel Gorman To: Linux-MM Cc: Andrew Morton , Michal Hocko , NeilBrown , Thierry Reding , Matthew Wilcox , Vlastimil Babka , LKML , Mel Gorman Subject: [PATCH 5/6] mm/page_alloc: Give GFP_ATOMIC and non-blocking allocations access to reserves Date: Tue, 29 Nov 2022 15:17:00 +0000 Message-Id: <20221129151701.23261-6-mgorman@techsingularity.net> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20221129151701.23261-1-mgorman@techsingularity.net> References: <20221129151701.23261-1-mgorman@techsingularity.net> MIME-Version: 1.0 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1669735087; a=rsa-sha256; cv=none; b=mTUrfr3d5TaAjJx3E+9nxO2P2JPUSY+3D2iuAWBPi33Qqe6AVbQQaU2bRBxhb2T56EBtgT t54qF2FAQOTQpFBKwc50sFnVvFicwsIQjRBn4aaKDhv01jo1Su4EReuHQ3Nnm3y+j0j0i7 4LJkuW5bp+sOBaCCuVuN+B93jntSne8= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf24.hostedemail.com: domain of mgorman@techsingularity.net designates 81.17.249.32 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1669735087; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CjtUDExeBT/P5kumqIiHMCjmeHSTBsjsXEcG220K8Dk=; b=YQm9hAX4+Iwt4AxUm5YW4YqECBRyyEdjTMuAHqWjhYmk+G8Q2Y0g7GFOvIsN9Rgh8BV2+H cRWWUwkq4g/QNjAZDIV2MWIP976yl5+qsUOQ+mCGXZYsf0Ruzc7Q0TD8uu+iVjR93G9sby hNaZXU7bziyyz3hP7QzPypVXkDCb3Qc= X-Rspamd-Queue-Id: 336F818001A X-Rspam-User: Authentication-Results: imf24.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf24.hostedemail.com: domain of mgorman@techsingularity.net designates 81.17.249.32 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net X-Rspamd-Server: rspam09 X-Stat-Signature: owpfzxsnff46rb1n8ufufgbemmayz74z X-HE-Tag: 1669735086-670988 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: Explicit GFP_ATOMIC allocations get flagged ALLOC_HARDER which is a bit vague. In preparation for removing __GFP_ATOMIC, give GFP_ATOMIC and other non-blocking allocation requests equal access to reserve. Rename ALLOC_HARDER to ALLOC_NON_BLOCK to make it more clear what the flag means. Signed-off-by: Mel Gorman --- mm/internal.h | 7 +++++-- mm/page_alloc.c | 23 +++++++++++++---------- 2 files changed, 18 insertions(+), 12 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index 370500718732..98b1e526559d 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -743,7 +743,10 @@ unsigned int reclaim_clean_pages_from_list(struct zone *zone, #define ALLOC_OOM ALLOC_NO_WATERMARKS #endif -#define ALLOC_HARDER 0x10 /* try to alloc harder */ +#define ALLOC_NON_BLOCK 0x10 /* Caller cannot block. Allow access + * to 25% of the min watermark or + * 62.5% if __GFP_HIGH is set. + */ #define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% * of the min watermark. */ @@ -758,7 +761,7 @@ unsigned int reclaim_clean_pages_from_list(struct zone *zone, #define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ /* Flags that allow allocations below the min watermark. */ -#define ALLOC_RESERVES (ALLOC_HARDER|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) +#define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) enum ttu_flags; struct tlbflush_unmap_batch; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 85a87d0ac57a..6bee987ec9a3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3994,7 +3994,7 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, * if it cannot get memory quickly, particularly if it's * also __GFP_HIGH. */ - if (alloc_flags & (ALLOC_HARDER|ALLOC_HIGHATOMIC)) + if (alloc_flags & (ALLOC_NON_BLOCK|ALLOC_HIGHATOMIC)) min -= min / 4; /* @@ -4846,28 +4846,30 @@ gfp_to_alloc_flags(gfp_t gfp_mask, unsigned int order) * The caller may dip into page reserves a bit more if the caller * cannot run direct reclaim, or if the caller has realtime scheduling * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will - * set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_MIN_RESERVE(__GFP_HIGH). + * set both ALLOC_NON_BLOCK and ALLOC_MIN_RESERVE(__GFP_HIGH). */ alloc_flags |= (__force int) (gfp_mask & (__GFP_HIGH | __GFP_KSWAPD_RECLAIM)); - if (gfp_mask & __GFP_ATOMIC) { + if (!(gfp_mask & __GFP_RECLAIM)) { /* * Not worth trying to allocate harder for __GFP_NOMEMALLOC even * if it can't schedule. */ if (!(gfp_mask & __GFP_NOMEMALLOC)) { - alloc_flags |= ALLOC_HARDER; + alloc_flags |= ALLOC_NON_BLOCK; if (order > 0) alloc_flags |= ALLOC_HIGHATOMIC; } /* - * Ignore cpuset mems for GFP_ATOMIC rather than fail, see the - * comment for __cpuset_node_allowed(). + * Ignore cpuset mems for non-blocking __GFP_HIGH (probably + * GFP_ATOMIC) rather than fail, see the comment for + * __cpuset_node_allowed(). */ - alloc_flags &= ~ALLOC_CPUSET; + if (alloc_flags & ALLOC_MIN_RESERVE) + alloc_flags &= ~ALLOC_CPUSET; } else if (unlikely(rt_task(current)) && in_task()) alloc_flags |= ALLOC_MIN_RESERVE; @@ -5299,11 +5301,12 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, /* * Help non-failing allocations by giving them access to memory - * reserves but do not use ALLOC_NO_WATERMARKS because this + * reserves normally used for high priority non-blocking + * allocations but do not use ALLOC_NO_WATERMARKS because this * could deplete whole memory reserves which would just make - * the situation worse + * the situation worse. */ - page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_MIN_RESERVE|ALLOC_HARDER, ac); + page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_MIN_RESERVE|ALLOC_NON_BLOCK, ac); if (page) goto got_pg;