sched: sched_clock_idle_[sleep|wakeup]_event()

construct a more or less wall-clock time out of sched_clock(), by
using ACPI-idle's existing knowledge about how much time we spent
idling. This allows the rq clock to work around TSC-stops-in-C2,
TSC-gets-corrupted-in-C3 type of problems.

( Besides the scheduler's statistics this also benefits blktrace and
  printk-timestamps as well. )

Furthermore, the precise before-C2/C3-sleep and after-C2/C3-wakeup
callbacks allow the scheduler to get out the most of the period where
the CPU has a reliable TSC. This results in slightly more precise
task statistics.

the ACPI bits were acked by Len.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Len Brown <len.brown@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 87e524762b85..ab18f45f2ab2 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -154,10 +154,11 @@ static void print_cpu(struct seq_file *m, int cpu)
         P(next_balance);
         P(curr->pid);
         P(clock);
+        P(idle_clock);
         P(prev_clock_raw);
         P(clock_warps);
         P(clock_overflows);
-        P(clock_unstable_events);
+        P(clock_deep_idle_events);
         P(clock_max_delta);
         P(cpu_load[0]);
         P(cpu_load[1]);