Marcelo Tosatti 7bd20b6b87 workqueue: mark power efficient workqueue as unbounded if nohz_full enabled
A customer using nohz_full has experienced the following interruption:

oslat-1004510 [018] timer_cancel:         timer=0xffff90a7ca663cf8
oslat-1004510 [018] timer_expire_entry:   timer=0xffff90a7ca663cf8 function=delayed_work_timer_fn now=4709188240 baseclk=4709188240
oslat-1004510 [018] workqueue_queue_work: work struct=0xffff90a7ca663cd8 function=fb_flashcursor workqueue=events_power_efficient req_cpu=8192 cpu=18
oslat-1004510 [018] workqueue_activate_work: work struct 0xffff90a7ca663cd8
oslat-1004510 [018] sched_wakeup:         kworker/18:1:326 [120] CPU:018
oslat-1004510 [018] timer_expire_exit:    timer=0xffff90a7ca663cf8
oslat-1004510 [018] irq_work_entry:       vector=246
oslat-1004510 [018] irq_work_exit:        vector=246
oslat-1004510 [018] tick_stop:            success=0 dependency=SCHED
oslat-1004510 [018] hrtimer_start:        hrtimer=0xffff90a70009cb00 function=tick_sched_timer/0x0 ...
oslat-1004510 [018] softirq_exit:         vec=1 [action=TIMER]
oslat-1004510 [018] softirq_entry:        vec=7 [action=SCHED]
oslat-1004510 [018] softirq_exit:         vec=7 [action=SCHED]
oslat-1004510 [018] tick_stop:            success=0 dependency=SCHED
oslat-1004510 [018] sched_switch:         oslat:1004510 [120] R ==> kworker/18:1:326 [120]
kworker/18:1-326 [018] workqueue_execute_start: work struct 0xffff90a7ca663cd8: function fb_flashcursor
kworker/18:1-326 [018] workqueue_queue_work: work struct=0xffff9078f119eed0 function=drm_fb_helper_damage_work workqueue=events req_cpu=8192 cpu=18
kworker/18:1-326 [018] workqueue_activate_work: work struct 0xffff9078f119eed0
kworker/18:1-326 [018] timer_start:          timer=0xffff90a7ca663cf8 function=delayed_work_timer_fn ...

Set wq_power_efficient to true, in case nohz_full is enabled.
This makes the power efficient workqueue be unbounded, which allows
workqueue items there to be moved to HK CPUs.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2024-01-19 13:55:47 -10:00
2023-12-20 19:26:31 -05:00
2023-12-20 15:02:58 -08:00
2022-09-28 09:02:20 +02:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 3.7 GiB
Languages
C 97.1%
Assembly 1%
Shell 0.6%
Rust 0.4%
Python 0.4%
Other 0.3%