Re: [PATCH] fs: use wq_has_sleeper() in end_dir_add()

From: Christian Brauner
Date: Mon Mar 17 2025 - 11:06:35 EST


On Mon, 17 Mar 2025 00:24:21 +0100, Mateusz Guzik wrote:
> The routine is used a lot, while the wakeup almost never has anyone to
> deal with.
>
> wake_up_all() takes an irq-protected spinlock, wq_has_sleeper() "only"
> contains a full fence -- not free by any means, but still cheaper.
>
> Sample result tracing waiters using a custom probe during -j 20 kernel
> build (0 - no waiters, 1 - waiters):
>
> [...]

Applied to the vfs-6.15.misc branch of the vfs/vfs.git tree.
Patches in the vfs-6.15.misc branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs-6.15.misc

[1/1] fs: use wq_has_sleeper() in end_dir_add()
https://git.kernel.org/vfs/vfs/c/f81ad90aa97e