Two doc update patches and the following three fixes:
- On single node systems, the default pool is used but the node_nr_active
for the default pool was set to min_active. This effectively limited the
max concurrency of unbound pools on single node systems to 8 causing
performance regressions on some workloads. Fixed by setting the default
pool's node_nr_active to max_active.
- wq_update_node_max_active() could trigger divide-by-zero if the
intersection between the allowed CPUs for an unbound workqueue and online
CPUs becomes empty.
- When kick_pool() was trying to repatriate a worker to a CPU in its pod by
setting task->wake_cpu, it didn't consider whether the CPU being selected
is online or not which obviously can lead to subobtimal behaviors. On
s390, this triggered a crash in arch code. The workqueue patch removes the
gross misbehavior but doesn't fix the crash completely as there's a race
window in which CPUs can go down after wake_cpu is set. Need to decide
whether the fix should be on the core or arch side.
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Merge tag 'wq-for-6.9-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fixes from Tejun Heo:
"Two doc update patches and the following three fixes:
- On single node systems, the default pool is used but the
node_nr_active for the default pool was set to min_active. This
effectively limited the max concurrency of unbound pools on single
node systems to 8 causing performance regressions on some
workloads. Fixed by setting the default pool's node_nr_active to
max_active.
- wq_update_node_max_active() could trigger divide-by-zero if the
intersection between the allowed CPUs for an unbound workqueue and
online CPUs becomes empty.
- When kick_pool() was trying to repatriate a worker to a CPU in its
pod by setting task->wake_cpu, it didn't consider whether the CPU
being selected is online or not which obviously can lead to
subobtimal behaviors. On s390, this triggered a crash in arch code.
The workqueue patch removes the gross misbehavior but doesn't fix
the crash completely as there's a race window in which CPUs can go
down after wake_cpu is set. Need to decide whether the fix should
be on the core or arch side"
* tag 'wq-for-6.9-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Fix divide error in wq_update_node_max_active()
workqueue: The default node_nr_active should have its max set to max_active
workqueue: Fix selection of wake_cpu in kick_pool()
docs/zh_CN: core-api: Update translation of workqueue.rst to 6.9-rc1
Documentation/core-api: Update events_freezable_power references.
98369dccd2