timers: split process wide cpu clocks/timers

[linux-2.6-omap-h63xx.git] / include / linux / sched.h

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 2e0646a3031466532bc748ac1e05cfeeb9cea31e..082d7619b3a1e0ecc456828ba58a518028595fb6 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -443,7 +443,6 @@ struct pacct_struct {
  * @utime:             time spent in user mode, in &cputime_t units
  * @stime:             time spent in kernel mode, in &cputime_t units
  * @sum_exec_runtime:  total time spent on the CPU, in nanoseconds
- * @lock:              lock for fields in this struct
  *
  * This structure groups together three kinds of CPU time that are
  * tracked for threads and thread groups.  Most things considering
@@ -454,23 +453,33 @@ struct task_cputime {
        cputime_t utime;
        cputime_t stime;
        unsigned long long sum_exec_runtime;
-       spinlock_t lock;
 };
 /* Alternate field names when used to cache expirations. */
 #define prof_exp       stime
 #define virt_exp       utime
 #define sched_exp      sum_exec_runtime
 
+#define INIT_CPUTIME   \
+       (struct task_cputime) {                                 \
+               .utime = cputime_zero,                          \
+               .stime = cputime_zero,                          \
+               .sum_exec_runtime = 0,                          \
+       }
+
 /**
- * struct thread_group_cputime - thread group interval timer counts
- * @totals:            thread group interval timers; substructure for
- *                     uniprocessor kernel, per-cpu for SMP kernel.
+ * struct thread_group_cputimer - thread group interval timer counts
+ * @cputime:           thread group interval timers.
+ * @running:           non-zero when there are timers running and
+ *                     @cputime receives updates.
+ * @lock:              lock for fields in this struct.
  *
  * This structure contains the version of task_cputime, above, that is
- * used for thread group CPU clock calculations.
+ * used for thread group CPU timer calculations.
  */
-struct thread_group_cputime {
-       struct task_cputime totals;
+struct thread_group_cputimer {
+       struct task_cputime cputime;
+       int running;
+       spinlock_t lock;
 };
 
 /*
@@ -519,10 +528,10 @@ struct signal_struct {
        cputime_t it_prof_incr, it_virt_incr;
 
        /*
-        * Thread group totals for process CPU clocks.
-        * See thread_group_cputime(), et al, for details.
+        * Thread group totals for process CPU timers.
+        * See thread_group_cputimer(), et al, for details.
         */
-       struct thread_group_cputime cputime;
+       struct thread_group_cputimer cputimer;
 
        /* Earliest-expiration cache. */
        struct task_cputime cputime_expires;
@@ -2191,27 +2200,26 @@ static inline int spin_needbreak(spinlock_t *lock)
 /*
  * Thread group CPU time accounting.
  */
+void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
 
 static inline
-void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
+void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times)
 {
-       struct task_cputime *totals = &tsk->signal->cputime.totals;
+       struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
        unsigned long flags;
 
-       spin_lock_irqsave(&totals->lock, flags);
-       *times = *totals;
-       spin_unlock_irqrestore(&totals->lock, flags);
+       WARN_ON(!cputimer->running);
+
+       spin_lock_irqsave(&cputimer->lock, flags);
+       *times = cputimer->cputime;
+       spin_unlock_irqrestore(&cputimer->lock, flags);
 }
 
 static inline void thread_group_cputime_init(struct signal_struct *sig)
 {
-       sig->cputime.totals = (struct task_cputime){
-               .utime = cputime_zero,
-               .stime = cputime_zero,
-               .sum_exec_runtime = 0,
-       };
-
-       spin_lock_init(&sig->cputime.totals.lock);
+       sig->cputimer.cputime = INIT_CPUTIME;
+       spin_lock_init(&sig->cputimer.lock);
+       sig->cputimer.running = 0;
 }
 
 static inline void thread_group_cputime_free(struct signal_struct *sig)