Re: (subset) re-enable IOCB_NOWAIT writes to files v2

[Christian Brauner <brauner@kernel.org>]

On Thu, 20 Nov 2025 07:47:21 +0100, Christoph Hellwig wrote:
> commit 66fa3cedf16a ("fs: Add async write file modification handling.")
> effectively disabled IOCB_NOWAIT writes as timestamp updates currently
> always require blocking, and the modern timestamp resolution means we
> always update timestamps.  This leads to a lot of context switches from
> applications using io_uring to submit file writes, making it often worse
> than using the legacy aio code that is not using IOCB_NOWAIT.
> 
> [...]

Applied to the vfs-6.19.misc branch of the vfs/vfs.git tree.
Patches in the vfs-6.19.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-6.19.misc

[01/16] fs: refactor file timestamp update logic
        https://git.kernel.org/vfs/vfs/c/3cd9a42f1b5e
[02/16] fs: lift the FMODE_NOCMTIME check into file_update_time_flags
        https://git.kernel.org/vfs/vfs/c/7f30e7a42371
[03/16] fs: export vfs_utimes
        https://git.kernel.org/vfs/vfs/c/013983665227
[04/16] btrfs: use vfs_utimes to update file timestamps
        https://git.kernel.org/vfs/vfs/c/ded99587047c
[05/16] btrfs: fix the comment on btrfs_update_time
        https://git.kernel.org/vfs/vfs/c/f981264ae75e
[06/16] orangefs: use inode_update_timestamps directly
        https://git.kernel.org/vfs/vfs/c/eff094a58d00