mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-07 19:30:30 +09:00
3881b86128
When external events like CPU offlining or user events like changing the cpu list of an ancestor cpuset happen, update_cpumasks_hier() will be called to update the effective cpus of each of the affected cpusets. That will then call update_parent_subparts_cpumask() if partitions are impacted. Currently, these events may cause update_parent_subparts_cpumask() to return error if none of the requested cpus are available or it will consume all the cpus in the parent partition root. Handling these errors is problematic as the states may become inconsistent. Instead of letting update_parent_subparts_cpumask() return error, a new error state (-1) is added to the partition_root_state flag to designate the fact that the partition is no longer valid. IOW, it is no longer a real partition root, but the CS_CPU_EXCLUSIVE flag will still be set as it can be changed back to a real one if favorable change happens later on. This new error state is set internally and user cannot write this new value to "cpuset.sched.partition". Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> 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.