From e4b70fe94501d795895bdb9291b96afe43e4e75f Mon Sep 17 00:00:00 2001
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Date: Wed, 20 Jun 2018 22:32:55 +0530
Subject: [PATCH] sched/numa: Update the scan period without holding the
numa_group lock
References: bnc#1101669 optimise numa balancing for fast migrate
Patch-mainline: v4.19-rc1
Git-commit: 30619c89b17d46808b4cdf5b3f81b6a01ade1473
The metrics for updating scan periods are local or task specific.
Currently this update happens under the numa_group lock, which seems
unnecessary. Hence move this update outside the lock.
Running SPECjbb2005 on a 4 node machine and comparing bops/JVM
JVMS LAST_PATCH WITH_PATCH %CHANGE
16 25355.9 25645.4 1.141
1 72812 72142 -0.92
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Rik van Riel <riel@surriel.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1529514181-9842-15-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
kernel/sched/fair.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 0b5b2a011a9c..bb545ec07de7 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2228,8 +2228,6 @@ static void task_numa_placement(struct task_struct *p)
}
}
- update_task_scan_period(p, fault_types[0], fault_types[1]);
-
if (p->numa_group) {
numa_group_count_active_nodes(p->numa_group);
spin_unlock_irq(group_lock);
@@ -2244,6 +2242,8 @@ static void task_numa_placement(struct task_struct *p)
if (task_node(p) != p->numa_preferred_nid)
numa_migrate_preferred(p);
}
+
+ update_task_scan_period(p, fault_types[0], fault_types[1]);
}
static inline int get_numa_group(struct numa_group *grp)