aae17ebb53
When __queue_delayed_work() is called, it chooses a cpu for handling the timer interrupt. As of today, it will pick either the cpu passed as parameter or the last cpu used for this. This is not good if a system does use CPU isolation, because it can take away some valuable cpu time to: 1 - deal with the timer interrupt, 2 - schedule-out the desired task, 3 - queue work on a random workqueue, and 4 - schedule the desired task back to the cpu. So to fix this, during __queue_delayed_work(), if cpu isolation is in place, pick a random non-isolated cpu to handle the timer interrupt. As an optimization, if the current cpu is not isolated, use it instead of looking for another candidate. Signed-off-by: Leonardo Bras <leobras@redhat.com> Signed-off-by: Tejun Heo <tj@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.
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.