tree f48968ecb804154407bb5599278c67ac8e0e27cd
parent 6d87669357936bffa1e8fea7a4e7743e76905736
author Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1365692831 -0700
committer Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1367106767 -0700

kthread: Document ways of reducing OS jitter due to per-CPU kthreads

The Linux kernel uses a number of per-CPU kthreads, any of which might
contribute to OS jitter at any time.  The usual approach to normal
kthreads, namely to bind them to a "housekeeping" CPU, does not work
with these kthreads because they cannot operate correctly if moved to
some other CPU.  This commit therefore lists ways of controlling OS
jitter from the Linux kernel's per-CPU kthreads.  It also lists some
ways of diagnosing excessive jitter.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Olivier Baetz <olivier.baetz@novasparks.com>
Cc: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Borislav Petkov <bp@suse.de>