Jens Axboe
033b667a82
Even if blk-rq-qos isn't used or configured, dipping into the queue to fetch ->rq_qos is a noticeable slowdown and visible in profiles. Add an unlikely static key around blk-rq-qos, to avoid fetching this cacheline if blk-iolatency or blk-wbt isn't configured or used. Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> 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 reStructuredText 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.