5c2469e0a2
Earlier kernels had SQPOLL threads that could share across anything, as we grabbed the context we needed on a per-ring basis. This is no longer the case, so only allow attaching directly if we're in the same thread group. That is the common use case. For non-group tasks, just setup a new context and thread as we would've done if sharing wasn't set. This isn't 100% ideal in terms of CPU utilization for the forked and share case, but hopefully that isn't much of a concern. If it is, there are plans in motion for how to improve that. Most importantly, we want to avoid app side regressions where sharing worked before and now doesn't. With this patch, functionality is equivalent to previous kernels that supported IORING_SETUP_ATTACH_WQ with SQPOLL. Reported-by: Stefan Metzmacher <metze@samba.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.