Re: [PATCH 0/3] sbitmap: Fix two issues in the per-bitmap wakeup counter code

From: Jens Axboe
Date: Wed Nov 16 2022 - 13:53:05 EST


On Tue, 15 Nov 2022 17:45:50 -0500, Gabriel Krisman Bertazi wrote:
> Jan reported two issues in the original thread.
>
> The first is that wake_index was not updated after returning from
> sbq_wake_ptr which meant we'd have to empty the wq before moving to the
> next one. Patch 1/3 in this series reorders the code to avoid this
> condition, increasing fairness of queue selection and preventing
> starvation. I sent this patch already on the other thread and Jan
> reviewed it, but since it is a small one, and a dependency for the
> other, I'm resending it a along this series.
>
> [...]

Applied, thanks!

[1/3] sbitmap: Advance the queue index before waking up a queue
commit: 976570b4ecd30d3ec6e1b0910da8e5edc591f2b6
[2/3] wait: Return number of exclusive waiters awaken
commit: ee7dc86b6d3e3b86c2c487f713eda657850de238
[3/3] sbitmap: Try each queue to wake up at least one waiter
commit: 26edb30dd1c0c9be11fa676b4f330ada7b794ba6

Best regards,
--
Jens Axboe