nohz: Warn if the machine can not perform nohz_full
authorSteven Rostedt <rostedt@goodmis.org>
Fri, 10 May 2013 21:12:28 +0000 (17:12 -0400)
committerFrederic Weisbecker <fweisbec@gmail.com>
Wed, 19 Jun 2013 23:15:51 +0000 (01:15 +0200)
commite12d0271774fea9fddf1e2a7952a0bffb2ee8e8b
tree6bd6a506cd535836ec419055cc4c20f0a6648224
parent7d132055814ef17a6c7b69f342244c410a5e000f
nohz: Warn if the machine can not perform nohz_full

If the user configures NO_HZ_FULL and defines nohz_full=XXX on the
kernel command line, or enables NO_HZ_FULL_ALL, but nohz fails
due to the machine having a unstable clock, warn about it.

We do not want users thinking that they are getting the benefit
of nohz when their machine can not support it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
kernel/time/tick-sched.c