From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f69.google.com (mail-oi0-f69.google.com [209.85.218.69]) by kanga.kvack.org (Postfix) with ESMTP id 12A2E6B03DE for ; Wed, 21 Jun 2017 07:48:04 -0400 (EDT) Received: by mail-oi0-f69.google.com with SMTP id a199so79628405oib.2 for ; Wed, 21 Jun 2017 04:48:04 -0700 (PDT) Received: from smtp.codeaurora.org (smtp.codeaurora.org. [198.145.29.96]) by mx.google.com with ESMTPS id 22si2242299otj.313.2017.06.21.04.48.02 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 21 Jun 2017 04:48:02 -0700 (PDT) From: Vinayak Menon Subject: [PATCH] mm: avoid taking zone lock in pagetypeinfo_showmixed Date: Wed, 21 Jun 2017 17:17:23 +0530 Message-Id: <1498045643-12257-1-git-send-email-vinmenon@codeaurora.org> Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, vbabka@suse.cz, iamjoonsoo.kim@lge.com, zhongjiang@huawei.com, sergey.senozhatsky@gmail.com, sudipm.mukherjee@gmail.com, hannes@cmpxchg.org, mgorman@techsingularity.net, mhocko@suse.com, bigeasy@linutronix.de, rientjes@google.com, minchan@kernel.org Cc: linux-mm@kvack.org, Vinayak Menon pagetypeinfo_showmixedcount_print is found to take a lot of time to complete and it does this holding the zone lock and disabling interrupts. In some cases it is found to take more than a second (On a 2.4GHz,8Gb RAM,arm64 cpu). Avoid taking the zone lock similar to what is done by read_page_owner, which means possibility of inaccurate results. Signed-off-by: Vinayak Menon --- mm/page_owner.c | 6 +++++- mm/vmstat.c | 24 ++++++++++++++---------- 2 files changed, 19 insertions(+), 11 deletions(-) diff --git a/mm/page_owner.c b/mm/page_owner.c index c3cee24..401feb0 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -281,7 +281,11 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m, continue; if (PageBuddy(page)) { - pfn += (1UL << page_order(page)) - 1; + unsigned long freepage_order; + + freepage_order = page_order_unsafe(page); + if (freepage_order < MAX_ORDER) + pfn += (1UL << freepage_order) - 1; continue; } diff --git a/mm/vmstat.c b/mm/vmstat.c index f5fa1bd..8cefdad 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1129,7 +1129,7 @@ static void frag_stop(struct seq_file *m, void *arg) * If @assert_populated is true, only use callback for zones that are populated. */ static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat, - bool assert_populated, + bool assert_populated, bool nolock, void (*print)(struct seq_file *m, pg_data_t *, struct zone *)) { struct zone *zone; @@ -1140,9 +1140,11 @@ static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat, if (assert_populated && !populated_zone(zone)) continue; - spin_lock_irqsave(&zone->lock, flags); + if (!nolock) + spin_lock_irqsave(&zone->lock, flags); print(m, pgdat, zone); - spin_unlock_irqrestore(&zone->lock, flags); + if (!nolock) + spin_unlock_irqrestore(&zone->lock, flags); } } #endif @@ -1165,7 +1167,7 @@ static void frag_show_print(struct seq_file *m, pg_data_t *pgdat, static int frag_show(struct seq_file *m, void *arg) { pg_data_t *pgdat = (pg_data_t *)arg; - walk_zones_in_node(m, pgdat, true, frag_show_print); + walk_zones_in_node(m, pgdat, true, false, frag_show_print); return 0; } @@ -1206,7 +1208,7 @@ static int pagetypeinfo_showfree(struct seq_file *m, void *arg) seq_printf(m, "%6d ", order); seq_putc(m, '\n'); - walk_zones_in_node(m, pgdat, true, pagetypeinfo_showfree_print); + walk_zones_in_node(m, pgdat, true, false, pagetypeinfo_showfree_print); return 0; } @@ -1258,7 +1260,8 @@ static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg) for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) seq_printf(m, "%12s ", migratetype_names[mtype]); seq_putc(m, '\n'); - walk_zones_in_node(m, pgdat, true, pagetypeinfo_showblockcount_print); + walk_zones_in_node(m, pgdat, true, false, + pagetypeinfo_showblockcount_print); return 0; } @@ -1284,7 +1287,8 @@ static void pagetypeinfo_showmixedcount(struct seq_file *m, pg_data_t *pgdat) seq_printf(m, "%12s ", migratetype_names[mtype]); seq_putc(m, '\n'); - walk_zones_in_node(m, pgdat, true, pagetypeinfo_showmixedcount_print); + walk_zones_in_node(m, pgdat, true, true, + pagetypeinfo_showmixedcount_print); #endif /* CONFIG_PAGE_OWNER */ } @@ -1448,7 +1452,7 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, static int zoneinfo_show(struct seq_file *m, void *arg) { pg_data_t *pgdat = (pg_data_t *)arg; - walk_zones_in_node(m, pgdat, false, zoneinfo_show_print); + walk_zones_in_node(m, pgdat, false, false, zoneinfo_show_print); return 0; } @@ -1854,7 +1858,7 @@ static int unusable_show(struct seq_file *m, void *arg) if (!node_state(pgdat->node_id, N_MEMORY)) return 0; - walk_zones_in_node(m, pgdat, true, unusable_show_print); + walk_zones_in_node(m, pgdat, true, false, unusable_show_print); return 0; } @@ -1906,7 +1910,7 @@ static int extfrag_show(struct seq_file *m, void *arg) { pg_data_t *pgdat = (pg_data_t *)arg; - walk_zones_in_node(m, pgdat, true, extfrag_show_print); + walk_zones_in_node(m, pgdat, true, false, extfrag_show_print); return 0; } -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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