RE: [PATCH -tip V2 00/10] workqueue: break affinity initiatively
From: Dexuan Cui
Date: Wed Dec 23 2020 - 15:40:43 EST
> From: Dexuan Cui
> Sent: Wednesday, December 23, 2020 12:27 PM
> ...
> The warning only repros if there are more than 1 node, and it only prints once
> for the first vCPU of the second node (i.e. node #1).
A correction: if I configure the 32 vCPUs evenly into 4 nodes, I get the warning
once for node #1~#3, respectively.
Thanks,
-- Dexuan
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2376,9 +2376,14 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
* For kernel threads that do indeed end up on online &&
* !active we want to ensure they are strict per-CPU threads.
*/
- WARN_ON(cpumask_intersects(new_mask, cpu_online_mask) &&
+ WARN(cpumask_intersects(new_mask, cpu_online_mask) &&
!cpumask_intersects(new_mask, cpu_active_mask) &&
- p->nr_cpus_allowed != 1);
+ p->nr_cpus_allowed != 1, "%*pbl, %*pbl, %*pbl, %d\n",
+ cpumask_pr_args(new_mask),
+ cpumask_pr_args(cpu_online_mask),
+ cpumask_pr_args(cpu_active_mask),
+ p->nr_cpus_allowed
+ );
}
[ 1.791611] smp: Bringing up secondary CPUs ...
[ 1.795225] x86: Booting SMP configuration:
[ 1.798964] .... node #0, CPUs: #1 #2 #3 #4 #5 #6 #7
[ 1.807068] .... node #1, CPUs: #8
[ 1.094226] smpboot: CPU 8 Converting physical 0 to logical die 1
[ 1.895211] ------------[ cut here ]------------
[ 1.899058] 8-15, 0-8, 0-7, 8
[ 1.899058] WARNING: CPU: 8 PID: 50 at kernel/sched/core.c:2386 __set_cpus_allowed_ptr+0x1c7/0x1e0
[ 1.899058] CPU: 8 PID: 50 Comm: cpuhp/8 Not tainted 5.10.0+ #4
[ 1.899058] RIP: 0010:__set_cpus_allowed_ptr+0x1c7/0x1e0
[ 1.899058] Call Trace:
[ 1.899058] worker_attach_to_pool+0x53/0xd0
[ 1.899058] create_worker+0xf9/0x190
[ 1.899058] alloc_unbound_pwq+0x3a5/0x3b0
[ 1.899058] wq_update_unbound_numa+0x112/0x1c0
[ 1.899058] workqueue_online_cpu+0x1d0/0x220
[ 1.899058] cpuhp_invoke_callback+0x82/0x4a0
[ 1.899058] cpuhp_thread_fun+0xb8/0x120
[ 1.899058] smpboot_thread_fn+0x198/0x230
[ 1.899058] kthread+0x13d/0x160
[ 1.899058] ret_from_fork+0x22/0x30
[ 1.903058] #9 #10 #11 #12 #13 #14 #15
[ 1.907092] .... node #2, CPUs: #16
[ 1.094226] smpboot: CPU 16 Converting physical 0 to logical die 2
[ 1.995205] ------------[ cut here ]------------
[ 1.999058] 16-23, 0-16, 0-15, 8
[ 1.999058] WARNING: CPU: 16 PID: 91 at kernel/sched/core.c:2386 __set_cpus_allowed_ptr+0x1c7/0x1e0
[ 1.999058] CPU: 16 PID: 91 Comm: cpuhp/16 Tainted: G W 5.10.0+ #4
[ 1.999058] RIP: 0010:__set_cpus_allowed_ptr+0x1c7/0x1e0
[ 1.999058] Call Trace:
[ 1.999058] worker_attach_to_pool+0x53/0xd0
[ 1.999058] create_worker+0xf9/0x190
[ 1.999058] alloc_unbound_pwq+0x3a5/0x3b0
[ 1.999058] wq_update_unbound_numa+0x112/0x1c0
[ 1.999058] workqueue_online_cpu+0x1d0/0x220
[ 1.999058] cpuhp_invoke_callback+0x82/0x4a0
[ 1.999058] cpuhp_thread_fun+0xb8/0x120
[ 1.999058] smpboot_thread_fn+0x198/0x230
[ 1.999058] kthread+0x13d/0x160
[ 1.999058] ret_from_fork+0x22/0x30
[ 2.003058] #17 #18 #19 #20 #21 #22 #23
[ 2.007092] .... node #3, CPUs: #24
[ 1.094226] smpboot: CPU 24 Converting physical 0 to logical die 3
[ 2.095220] ------------[ cut here ]------------
[ 2.099058] 24-31, 0-24, 0-23, 8
[ 2.099058] WARNING: CPU: 24 PID: 132 at kernel/sched/core.c:2386 __set_cpus_allowed_ptr+0x1c7/0x1e0
[ 2.099058] CPU: 24 PID: 132 Comm: cpuhp/24 Tainted: G W 5.10.0+ #4
[ 2.099058] Call Trace:
[ 2.099058] worker_attach_to_pool+0x53/0xd0
[ 2.099058] create_worker+0xf9/0x190
[ 2.099058] alloc_unbound_pwq+0x3a5/0x3b0
[ 2.099058] wq_update_unbound_numa+0x112/0x1c0
[ 2.099058] workqueue_online_cpu+0x1d0/0x220
[ 2.099058] cpuhp_invoke_callback+0x82/0x4a0
[ 2.099058] cpuhp_thread_fun+0xb8/0x120
[ 2.099058] smpboot_thread_fn+0x198/0x230
[ 2.099058] kthread+0x13d/0x160
[ 2.099058] ret_from_fork+0x22/0x30
[ 2.103058] #25 #26 #27 #28 #29 #30 #31
[ 2.108091] smp: Brought up 4 nodes, 32 CPUs
[ 2.115065] smpboot: Max logical packages: 4
[ 2.119067] smpboot: Total of 32 processors activated (146992.31 BogoMIPS)