tree fa7e44d9ad3eb22517f0724e71f9812f71a16ae2
parent f14eff1cc2f418a7c5e23aedc6a1bdca3343b871
author Arjan van de Ven <arjan@linux.intel.com> 1248114418 -0700
committer Ingo Molnar <mingo@elte.hu> 1251873848 +0200

sched: Provide iowait counters

For counting how long an application has been waiting for
(disk) IO, there currently is only the HZ sample driven
information available, while for all other counters in this
class, a high resolution version is available via
CONFIG_SCHEDSTATS.

In order to make an improved bootchart tool possible, we also
need a higher resolution version of the iowait time.

This patch below adds this scheduler statistic to the kernel.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4A64B813.1080506@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>