leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

sched/isolation: Isolate workqueues when "nohz_full=" is set

Browse Source 
As we prepare for offloading the residual 1hz scheduler ticks to
workqueue, let's affine those to housekeepers so that they don't
interrupt the CPUs that don't want to be disturbed.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1519186649-3242-5-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Frederic Weisbecker 2018-02-21 05:17:26 +01:00 committed by Ingo Molnar
parent 22ab8bc02a
commit 1bda3f8087
3 changed files with 5 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/sched/isolation.h
View File

@ -12,6 +12,7 @@ enum hk_flags {
HK_FLAG_SCHED = (1 << 3), HK_FLAG_SCHED = (1 << 3),
HK_FLAG_TICK = (1 << 4), HK_FLAG_TICK = (1 << 4),
HK_FLAG_DOMAIN = (1 << 5), HK_FLAG_DOMAIN = (1 << 5),
HK_FLAG_WQ = (1 << 6),
}; };
#ifdef CONFIG_CPU_ISOLATION #ifdef CONFIG_CPU_ISOLATION

3
kernel/sched/isolation.c
View File

@ -3,6 +3,7 @@
* any CPU: unbound workqueues, timers, kthreads and any offloadable work. * any CPU: unbound workqueues, timers, kthreads and any offloadable work.
* *
* Copyright (C) 2017 Red Hat, Inc., Frederic Weisbecker * Copyright (C) 2017 Red Hat, Inc., Frederic Weisbecker
* Copyright (C) 2017-2018 SUSE, Frederic Weisbecker
* *
*/ */
@ -119,7 +120,7 @@ static int __init housekeeping_nohz_full_setup(char *str)
{ {
unsigned int flags; unsigned int flags;
flags = HK_FLAG_TICK | HK_FLAG_TIMER | HK_FLAG_RCU | HK_FLAG_MISC; flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU | HK_FLAG_MISC;
return housekeeping_setup(str, flags); return housekeeping_setup(str, flags);
} }

3
kernel/workqueue.c
View File

@ -5565,12 +5565,13 @@ static void __init wq_numa_init(void)
int __init workqueue_init_early(void) int __init workqueue_init_early(void)
{ {
int std_nice[NR_STD_WORKER_POOLS] = { 0, HIGHPRI_NICE_LEVEL }; int std_nice[NR_STD_WORKER_POOLS] = { 0, HIGHPRI_NICE_LEVEL };
int hk_flags = HK_FLAG_DOMAIN | HK_FLAG_WQ;
int i, cpu; int i, cpu;
WARN_ON(__alignof__(struct pool_workqueue) < __alignof__(long long)); WARN_ON(__alignof__(struct pool_workqueue) < __alignof__(long long));
BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL)); BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL));
cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(HK_FLAG_DOMAIN)); cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(hk_flags));
pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC); pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC);