mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-02-26 05:11:44 -05:00
959bf2fd03
Our percpu code is a bit of an inconsistent mess:
* It rolls its own xchg(), but reuses cmpxchg_local()
* It uses various different flavours of preempt_{enable,disable}()
* It returns values even for the non-returning RmW operations
* It makes no use of LSE atomics outside of the cmpxchg() ops
* There are individual macros for different sizes of access, but these
are all funneled through a switch statement rather than dispatched
directly to the relevant case
This patch rewrites the per-cpu operations to address these shortcomings.
Whilst the new code is a lot cleaner, the big advantage is that we can
use the non-returning ST- atomic instructions when we have LSE.
Signed-off-by: Will Deacon <will.deacon@arm.com>
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.