[PATCH v2 0/2] locking/rwsem: Fix rwsem waiter optimistic spinning problem with RT tasks

From: Waiman Long
Date: Wed Oct 12 2022 - 09:33:59 EST


v2:
- Add an additional patch to limit the # of first waiter optimistic
spinning in the writer slowpath.

It turns out the current waiter optimistic spinning code does not work
that well if we have RT tasks in the mix. This patch series include
two different fixes to resolve those issues.

Waiman Long (2):
locking/rwsem: Prevent non-first waiter from spinning in down_write()
slowpath
locking/rwsem: Limit # of null owner retries for handoff writer

kernel/locking/rwsem.c | 31 ++++++++++++++++++++++++++-----
1 file changed, 26 insertions(+), 5 deletions(-)

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2.31.1