Re: [PATCH RFC 0/9] Launching processes with io_uring

[Josh Triplett <josh@joshtriplett.org>]

On Mon, Dec 09, 2024 at 06:43:02PM -0500, Gabriel Krisman Bertazi wrote:
> During LPC 2022, Josh Triplett proposed io_uring_spawn as a mechanism to
> fork and exec new processes through io_uring [1].  The goal, according
> to him, was to have a very efficient mechanism to quickly execute tasks,
> eliminating the multiple roundtrips to userspace required to fork,
> perform multiple $PATH lookup and finally execve.  In addition, he
> mentioned this would allow for a more simple implementation of
> preparatory tasks, such as file redirection configuration, and handling
> of stuff like posix_spawn_file_actions_t.
> 
> This RFC revives his original patchset.  I fixed all the pending issues
> I found with task submission, including the issue blocking the work at
> the time, a kernel corruption after a few spawns, converted the execve
> command into execveat* variant, cleaned up the code and surely
> introduced a few bugs of my own along the way.  At this point, I made it
> an RFC because I have a few outstanding questions about the design, in
> particular whether the CLONE context would be better implemented as a
> special io-wq case to avoid the exposure of io_issue_sqe and
> duplication of the dispatching logic.

Thank you for updating and debugging this! Much appreciated.