WQ_UNBOUND workqueue warnings from multiple drivers

From: Kamaljit Singh
Date: Mon Mar 18 2024 - 18:33:51 EST


Hello,

After switching from Kernel v6.6.2 to v6.6.21 we're now seeing these workqueue
warnings. I found a discussion thread about the the Intel drm driver here
https://lore.kernel.org/lkml/ZO-BkaGuVCgdr3wc@xxxxxxxxxxxxxxx/T/

and this related bug report https://gitlab.freedesktop.org/drm/intel/-/issues/9245
but that that drm fix isn't merged into v6.6.21. It appears that we may need the same
WQ_UNBOUND change to the nvme host tcp driver among others.
 
[Fri Mar 15 22:30:06 2024] workqueue: nvme_tcp_io_work [nvme_tcp] hogged CPU for >10000us 4 times, consider switching to WQ_UNBOUND
[Fri Mar 15 23:44:58 2024] workqueue: drain_vmap_area_work hogged CPU for >10000us 4 times, consider switching to WQ_UNBOUND
[Sat Mar 16 09:55:27 2024] workqueue: drain_vmap_area_work hogged CPU for >10000us 8 times, consider switching to WQ_UNBOUND
[Sat Mar 16 17:51:18 2024] workqueue: nvme_tcp_io_work [nvme_tcp] hogged CPU for >10000us 8 times, consider switching to WQ_UNBOUND
[Sat Mar 16 23:04:14 2024] workqueue: nvme_tcp_io_work [nvme_tcp] hogged CPU for >10000us 16 times, consider switching to WQ_UNBOUND
[Sun Mar 17 21:35:46 2024] perf: interrupt took too long (2707 > 2500), lowering kernel.perf_event_max_sample_rate to 73750
[Sun Mar 17 21:49:34 2024] workqueue: drain_vmap_area_work hogged CPU for >10000us 16 times, consider switching to WQ_UNBOUND
..
workqueue: drm_fb_helper_damage_work [drm_kms_helper] hogged CPU for >10000us 32 times, consider switching to WQ_UNBOUND
 
 
Thanks,
Kamaljit Singh