7464c0762e
When we have more than one CPU in system, counter synchronisation overhead can lead to a scenario that sched_clock goes backward when being read from different CPUs. This is accommodated by CONFIG_HAVE_UNSTABLE_SCHED_CLOCK, but it's unavailable on 32bit kernel. We don't want to risk sched_clock correctness, so if we have multiple CPU in system and CONFIG_HAVE_UNSTABLE_SCHED_CLOCK is not set, we just don't use counter as sched_clock source. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
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 reStructuredText 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.