a10b746f32
After commit cfe452afa565 ("workqueue: Affine rescuer threads and
unbound wqs", 2021-10-25) was merged, the kernel build process started
to emit the following compilation warning:
kernel/workqueue.c: In function 'workqueue_init_early':
kernel/workqueue.c:5944:6: warning: unused variable 'hk_flags' \
[-Wunused-variable]
int hk_flags = HK_FLAG_DOMAIN | HK_FLAG_WQ;
^~~~~~~~
This occurs because the aforementioned commit removes all users of the
hk_flags variable from the affected function, but does not remove the
(now) unused variable.
This commit removes the unused variable to avoid the compilation
warning.
Testing:
* An ISO image was built successfully using a monolithic build
procedure, and the kernel build logs were inspected to verify that the
warning is no longer emitted.
Change-Id: I622bf66716fb7bdf673a9e868b48b6979e71a3e5
Fixes: cfe452afa565 ("workqueue: Affine rescuer threads ...")
Closes-Bug: 1958143
Signed-off-by: M. Vefa Bicakci <vefa.bicakci@windriver.com>
62 lines
2.3 KiB
Diff
62 lines
2.3 KiB
Diff
From 6039b821dbe26c7708537e07276316dca36c1c0f Mon Sep 17 00:00:00 2001
|
|
From: "M. Vefa Bicakci" <vefa.bicakci@windriver.com>
|
|
Date: Thu, 9 Sep 2021 04:56:46 -0400
|
|
Subject: [PATCH] workqueue: Affine rescuer threads and unbound wqs
|
|
|
|
This commit ensures that workqueue rescuer threads are affined to the
|
|
platform CPUs specified by the "kthread_cpus" kernel argument. Prior to
|
|
this commit, rescuer threads could be bound to any CPU. Rescuer threads
|
|
are described in "kernel/workqueue.c" as follows:
|
|
|
|
"Regular work processing on a pool may block trying to create a new
|
|
worker which uses GFP_KERNEL allocation which has slight chance of
|
|
developing into deadlock if some works currently on the same queue
|
|
need to be processed to satisfy the GFP_KERNEL allocation. This is
|
|
the problem rescuer solves.
|
|
|
|
When such condition is possible, the pool summons rescuers of all
|
|
workqueues which have works queued on the pool and let them process
|
|
those works so that forward progress can be guaranteed."
|
|
|
|
This commit also affines unbound workqueues to the platform CPUs instead
|
|
of the housekeeping CPUs, because the latter can be a superset of the
|
|
former.
|
|
|
|
Signed-off-by: M. Vefa Bicakci <vefa.bicakci@windriver.com>
|
|
Signed-off-by: Jiping Ma <jiping.ma2@windriver.com>
|
|
---
|
|
kernel/workqueue.c | 5 ++---
|
|
1 file changed, 2 insertions(+), 3 deletions(-)
|
|
|
|
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
|
|
index 1a4151c6faa6..3e3bd8d75f3c 100644
|
|
--- a/kernel/workqueue.c
|
|
+++ b/kernel/workqueue.c
|
|
@@ -4242,7 +4242,7 @@ static int init_rescuer(struct workqueue_struct *wq)
|
|
}
|
|
|
|
wq->rescuer = rescuer;
|
|
- kthread_bind_mask(rescuer->task, cpu_possible_mask);
|
|
+ kthread_bind_mask(rescuer->task, cpu_kthread_mask);
|
|
wake_up_process(rescuer->task);
|
|
|
|
return 0;
|
|
@@ -5941,13 +5941,12 @@ static void __init wq_numa_init(void)
|
|
void __init workqueue_init_early(void)
|
|
{
|
|
int std_nice[NR_STD_WORKER_POOLS] = { 0, HIGHPRI_NICE_LEVEL };
|
|
- int hk_flags = HK_FLAG_DOMAIN | HK_FLAG_WQ;
|
|
int i, cpu;
|
|
|
|
BUILD_BUG_ON(__alignof__(struct pool_workqueue) < __alignof__(long long));
|
|
|
|
BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL));
|
|
- cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(hk_flags));
|
|
+ cpumask_copy(wq_unbound_cpumask, cpu_kthread_mask);
|
|
|
|
pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC);
|
|
|
|
--
|
|
2.29.2
|
|
|