1b1f0890fb
[ Upstream commit 0870b0d8b393dde53106678a1e2cec9dfa52f9b7 ] Typically, busy-polling durations are below 100 usec. When/if the busy-poller thread migrates to another cpu, local_clock() can be off by +/-2msec or more for small values of HZ, depending on the platform. Use ktimer_get_ns() to ensure deterministic behavior, which is the whole point of busy-polling. Fixes:0602129286("net: add low latency socket poll") Fixes:9a3c71aa80("net: convert low latency sockets to sched_clock()") Fixes:3708983452("sched, net: Fixup busy_loop_us_clock()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Mina Almasry <almasrymina@google.com> Cc: Willem de Bruijn <willemb@google.com> Reviewed-by: Joe Damato <jdamato@fastly.com> Link: https://patch.msgid.link/20240827114916.223377-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.