From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB9D3C433EF for ; Thu, 16 Dec 2021 12:47:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236932AbhLPMrZ (ORCPT ); Thu, 16 Dec 2021 07:47:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236919AbhLPMrW (ORCPT ); Thu, 16 Dec 2021 07:47:22 -0500 Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D15A6C061574 for ; Thu, 16 Dec 2021 04:47:21 -0800 (PST) Received: by mail-pl1-x62e.google.com with SMTP id w24so6665753ply.12 for ; Thu, 16 Dec 2021 04:47:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=qfj7Kw86wjF8KFyGsU//Y0rYlbxDXy3uM86gSdDXCRc=; b=z4AuqZxeVcb6wpYtFUqTMzD8/Affkzes9JAYGT/nT5HhTPYyc/O4sFAlblyYyNFaST oM/8NTASwc8c9EVWRK1RJEgwMorXCMOkDewYomMT9Nev/URBm0UafCIt0/HJ/noHPcCb HBTnfPD47dS9KAnjpGmuC8yf9TtChIqNnPeBfAtR6xzC3QXfkQl5Fic4lk0iXWQoSZ2r M525FXywCEUTO/gxIA1UvXgyQr0QLEE+GQ4Mr7jlbZhEgRRM2KkkPbVaDIuH7fE+fwa+ 6A8SHHDKOq/cKCb9q1Qkfqr0qQeC4iqGhcosz/L97XQwjhNeg2ZkcPL/0zxChfuK3Pu8 +fwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=qfj7Kw86wjF8KFyGsU//Y0rYlbxDXy3uM86gSdDXCRc=; b=yBbemYOgRFp4NqsZjLDyvGaME66hd7Xjg+jUr7MDyWOT3rAAW34XcIgy9DZC3TW1uM CUoLAJDOHRPRPkeZ6HQpjov8HZ6isgJw+uaW/d3W2dwCkEg0jujyu15moPo3gYm9a/Ed /YyPxsivd5LNDhyQnC/lAt+HA5A8DegzxermeOelyjjg2DKm/+yNdEvGSuBYDFFq50Og 0xecdkPZJEFZfEWU7nQddevnkj3kwtxBGYUBJ4IDoK7fwkFzkH+HSrf/seg8+kSzphsB C4osjBeHIlbOiIAYBXS0efKzyz432R/coLSzgBSe19woJwtA+7N0nn8TM1/K6GOnx5Ch 9l+g== X-Gm-Message-State: AOAM532qyXTG+kgNs2xfv6RXzokdT/5NvAKFh1rTgmQDDZtKn6y5xX6b 82WCBvOXUs1Yo+SdIoqDBChFR5AoNcoM/g== X-Google-Smtp-Source: ABdhPJwN2cf7IIDD1vBgv5C1ViFvLyzDyqrB2+lCRC37Bx2UckD74xWpFwTQXIULPGSp8+h4CxVK+w== X-Received: by 2002:a17:90a:aa88:: with SMTP id l8mr5973230pjq.20.1639658841369; Thu, 16 Dec 2021 04:47:21 -0800 (PST) Received: from C02DW0BEMD6R.bytedance.net ([139.177.225.243]) by smtp.gmail.com with ESMTPSA id h5sm6154309pfi.46.2021.12.16.04.47.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Dec 2021 04:47:21 -0800 (PST) From: Qi Zheng To: akpm@linux-foundation.org, gregkh@linuxfoundation.org, rafael@kernel.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, songmuchun@bytedance.com, Qi Zheng Subject: [PATCH 1/2] mm: add MemAvailable to per-node meminfo Date: Thu, 16 Dec 2021 20:46:54 +0800 Message-Id: <20211216124655.32247-2-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20211216124655.32247-1-zhengqi.arch@bytedance.com> References: <20211216124655.32247-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In /proc/meminfo, we can show the sum of all the available memory as "MemAvailable". Add the same counter also to per-node meminfo under /sys. With this counter, some processes that bind nodes can make some decisions by reading the "MemAvailable" of the corresponding nodes directly. Signed-off-by: Qi Zheng --- drivers/base/node.c | 4 ++++ include/linux/mm.h | 1 + include/linux/mmzone.h | 5 +++++ mm/page_alloc.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 59 insertions(+) diff --git a/drivers/base/node.c b/drivers/base/node.c index 87acc47e8951..deb2a7965ae4 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -375,8 +375,10 @@ static ssize_t node_read_meminfo(struct device *dev, struct sysinfo i; unsigned long sreclaimable, sunreclaimable; unsigned long swapcached = 0; + long available; si_meminfo_node(&i, nid); + available = si_mem_available_node(&i, nid); sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B); sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B); #ifdef CONFIG_SWAP @@ -386,6 +388,7 @@ static ssize_t node_read_meminfo(struct device *dev, "Node %d MemTotal: %8lu kB\n" "Node %d MemFree: %8lu kB\n" "Node %d MemUsed: %8lu kB\n" + "Node %d MemAvailable: %8lu kB\n" "Node %d SwapCached: %8lu kB\n" "Node %d Active: %8lu kB\n" "Node %d Inactive: %8lu kB\n" @@ -398,6 +401,7 @@ static ssize_t node_read_meminfo(struct device *dev, nid, K(i.totalram), nid, K(i.freeram), nid, K(i.totalram - i.freeram), + nid, K(available), nid, K(swapcached), nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) + node_page_state(pgdat, NR_ACTIVE_FILE)), diff --git a/include/linux/mm.h b/include/linux/mm.h index 1d4f731a8e18..34a5f5df388b 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2532,6 +2532,7 @@ extern void mem_init(void); extern void __init mmap_init(void); extern void show_mem(unsigned int flags, nodemask_t *nodemask); extern long si_mem_available(void); +extern long si_mem_available_node(struct sysinfo *val, int nid); extern void si_meminfo(struct sysinfo * val); extern void si_meminfo_node(struct sysinfo *val, int nid); #ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 936dc0b6c226..321c12f6272f 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1132,6 +1132,11 @@ extern struct zone *next_zone(struct zone *zone); ; /* do nothing */ \ else +#define for_each_pgdat_zone(pgdat, zone) \ + for (zone = (pgdat)->node_zones; \ + zone < (pgdat)->node_zones + MAX_NR_ZONES - 1 && zone; \ + zone++) + static inline struct zone *zonelist_zone(struct zoneref *zoneref) { return zoneref->zone; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index edfd6c81af82..31f5e3e335cf 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5731,6 +5731,55 @@ static inline void show_node(struct zone *zone) printk("Node %d ", zone_to_nid(zone)); } +/** + * si_mem_available_node - helper to calculate the size of available memory + * of the given node + * @val: pointer to struct sysinfo + * @nid: the node id + */ +long si_mem_available_node(struct sysinfo *val, int nid) +{ + long available; + unsigned long pagecache; + unsigned long reclaimable; + unsigned long wmark_low = 0; + struct pglist_data *pgdat = NODE_DATA(nid); + struct zone *zone; + + for_each_pgdat_zone(pgdat, zone) + wmark_low += low_wmark_pages(zone); + + /* + * Estimate the amount of memory available for userspace allocations, + * without causing swapping. + */ + available = val->freeram - pgdat->totalreserve_pages; + + /* + * Not all the page cache can be freed, otherwise the system will + * start swapping. Assume at least half of the page cache, or the + * low watermark worth of cache, needs to stay. + */ + pagecache = node_page_state(pgdat, NR_ACTIVE_FILE) + + node_page_state(pgdat, NR_INACTIVE_FILE); + pagecache -= min(pagecache / 2, wmark_low); + available += pagecache; + + /* + * Part of the reclaimable slab and other kernel memory consists of + * items that are in use, and cannot be freed. Cap this estimate at the + * low watermark. + */ + reclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B) + + node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE); + reclaimable -= min(reclaimable / 2, wmark_low); + available += reclaimable; + + if (available < 0) + available = 0; + return available; +} + long si_mem_available(void) { long available; -- 2.11.0