From f6f3f27597864d38bce5b4c346494970ecc19544 Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Thu, 8 Feb 2024 10:25:08 +0800 Subject: mm: compaction: early termination in compact_nodes() No need to continue try compact memory if pending fatal signal, allow loop termination earlier in compact_nodes(). The existing fatal_signal_pending() check does make compact_zone() break out of the while loop, but it still enters the next zone/next nid, and some unnecessary functions(eg, lru_add_drain) are called. There was no observable benefit from the new test, it is just found from code inspection when refactoring compact_node(). Link: https://lkml.kernel.org/r/20240208022508.1771534-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Cc: David Hildenbrand Signed-off-by: Andrew Morton --- mm/compaction.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) (limited to 'mm/compaction.c') diff --git a/mm/compaction.c b/mm/compaction.c index f146478b01bc..52ff6b9344c7 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -2808,7 +2808,7 @@ enum compact_result try_to_compact_pages(gfp_t gfp_mask, unsigned int order, * reaching score targets due to various back-off conditions, such as, * contention on per-node or per-zone locks. */ -static void compact_node(pg_data_t *pgdat, bool proactive) +static int compact_node(pg_data_t *pgdat, bool proactive) { int zoneid; struct zone *zone; @@ -2826,6 +2826,9 @@ static void compact_node(pg_data_t *pgdat, bool proactive) if (!populated_zone(zone)) continue; + if (fatal_signal_pending(current)) + return -EINTR; + cc.zone = zone; compact_zone(&cc, NULL); @@ -2837,18 +2840,25 @@ static void compact_node(pg_data_t *pgdat, bool proactive) cc.total_free_scanned); } } + + return 0; } /* Compact all zones of all nodes in the system */ -static void compact_nodes(void) +static int compact_nodes(void) { - int nid; + int ret, nid; /* Flush pending updates to the LRU lists */ lru_add_drain_all(); - for_each_online_node(nid) - compact_node(NODE_DATA(nid), false); + for_each_online_node(nid) { + ret = compact_node(NODE_DATA(nid), false); + if (ret) + return ret; + } + + return 0; } static int compaction_proactiveness_sysctl_handler(struct ctl_table *table, int write, @@ -2894,9 +2904,9 @@ static int sysctl_compaction_handler(struct ctl_table *table, int write, return -EINVAL; if (write) - compact_nodes(); + ret = compact_nodes(); - return 0; + return ret; } #if defined(CONFIG_SYSFS) && defined(CONFIG_NUMA) -- cgit v1.2.3