cputime: Use accessors to read task cputime stats
This is in preparation for the full dynticks feature. While
remotely reading the cputime of a task running in a full
dynticks CPU, we'll need to do some extra-computation. This
way we can account the time it spent tickless in userspace
since its last cputime snapshot.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index d65464e..8d7012b 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -899,6 +899,7 @@
static int use_apm_idle; /* = 0 */
static unsigned int last_jiffies; /* = 0 */
static unsigned int last_stime; /* = 0 */
+ cputime_t stime;
int apm_idle_done = 0;
unsigned int jiffies_since_last_check = jiffies - last_jiffies;
@@ -906,23 +907,23 @@
WARN_ONCE(1, "deprecated apm_cpu_idle will be deleted in 2012");
recalc:
+ task_cputime(current, NULL, &stime);
if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
use_apm_idle = 0;
- last_jiffies = jiffies;
- last_stime = current->stime;
} else if (jiffies_since_last_check > idle_period) {
unsigned int idle_percentage;
- idle_percentage = current->stime - last_stime;
+ idle_percentage = stime - last_stime;
idle_percentage *= 100;
idle_percentage /= jiffies_since_last_check;
use_apm_idle = (idle_percentage > idle_threshold);
if (apm_info.forbid_idle)
use_apm_idle = 0;
- last_jiffies = jiffies;
- last_stime = current->stime;
}
+ last_jiffies = jiffies;
+ last_stime = stime;
+
bucket = IDLE_LEAKY_MAX;
while (!need_resched()) {