Eric Dumazet
316580b69d
On 64bit arches, struct u64_stats_sync is empty and provides no help against load/store tearing. Using READ_ONCE()/WRITE_ONCE() would be needed. But the update side would be slightly more expensive. local64_t was defined so that we could use regular adds in a manner which is atomic wrt IRQs. However the u64_stats infra means we do not have to use local64_t on 32bit arches since the syncp provides the needed protection. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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.