sched: eliminate rq_clock() use

eliminate rq_clock() use by changing it to:

   update_rq_clock(rq)
   now = rq->clock;

identity transformation - no change in behavior.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 40 insertions, 17 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index d613723f324f..fe3c152d0c68 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -927,7 +927,10 @@ static int effective_prio(struct task_struct *p)
  */
 static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
 {
-        u64 now = rq_clock(rq);
+        u64 now;
+
+        update_rq_clock(rq);
+        now = rq->clock;
 
         if (p->state == TASK_UNINTERRUPTIBLE)
                 rq->nr_uninterruptible--;
@@ -941,7 +944,10 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
  */
 static inline void activate_idle_task(struct task_struct *p, struct rq *rq)
 {
-        u64 now = rq_clock(rq);
+        u64 now;
+
+        update_rq_clock(rq);
+        now = rq->clock;
 
         if (p->state == TASK_UNINTERRUPTIBLE)
                 rq->nr_uninterruptible--;
@@ -1664,7 +1670,8 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
         rq = task_rq_lock(p, &flags);
         BUG_ON(p->state != TASK_RUNNING);
         this_cpu = smp_processor_id(); /* parent's CPU */
-        now = rq_clock(rq);
+        update_rq_clock(rq);
+        now = rq->clock;
 
         p->prio = effective_prio(p);
 
@@ -2134,7 +2141,8 @@ void sched_exec(void)
 static void pull_task(struct rq *src_rq, struct task_struct *p,
                       struct rq *this_rq, int this_cpu)
 {
-        deactivate_task(src_rq, p, 0, rq_clock(src_rq));
+        update_rq_clock(src_rq);
+        deactivate_task(src_rq, p, 0, src_rq->clock);
         set_task_cpu(p, this_cpu);
         activate_task(this_rq, p, 0);
         /*
@@ -3221,7 +3229,8 @@ unsigned long long task_sched_runtime(struct task_struct *p)
         rq = task_rq_lock(p, &flags);
         ns = p->se.sum_exec_runtime;
         if (rq->curr == p) {
-                delta_exec = rq_clock(rq) - p->se.exec_start;
+                update_rq_clock(rq);
+                delta_exec = rq->clock - p->se.exec_start;
                 if ((s64)delta_exec > 0)
                         ns += delta_exec;
         }
@@ -3919,7 +3928,8 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
         BUG_ON(prio < 0 || prio > MAX_PRIO);
 
         rq = task_rq_lock(p, &flags);
-        now = rq_clock(rq);
+        update_rq_clock(rq);
+        now = rq->clock;
 
         oldprio = p->prio;
         on_rq = p->se.on_rq;
@@ -3966,7 +3976,8 @@ void set_user_nice(struct task_struct *p, long nice)
          * the task might be in the middle of scheduling on another CPU.
          */
         rq = task_rq_lock(p, &flags);
-        now = rq_clock(rq);
+        update_rq_clock(rq);
+        now = rq->clock;
         /*
          * The RT priorities are set via sched_setscheduler(), but we still
          * allow the 'normal' nice value to be set - but as expected
@@ -4228,8 +4239,10 @@ recheck:
                 goto recheck;
         }
         on_rq = p->se.on_rq;
-        if (on_rq)
-                deactivate_task(rq, p, 0, rq_clock(rq));
+        if (on_rq) {
+                update_rq_clock(rq);
+                deactivate_task(rq, p, 0, rq->clock);
+        }
         oldprio = p->prio;
         __setscheduler(rq, p, policy, param->sched_priority);
         if (on_rq) {
@@ -4981,8 +4994,10 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
                 goto out;
 
         on_rq = p->se.on_rq;
-        if (on_rq)
-                deactivate_task(rq_src, p, 0, rq_clock(rq_src));
+        if (on_rq) {
+                update_rq_clock(rq_src);
+                deactivate_task(rq_src, p, 0, rq_src->clock);
+        }
         set_task_cpu(p, dest_cpu);
         if (on_rq) {
                 activate_task(rq_dest, p, 0);
@@ -5215,7 +5230,8 @@ static void migrate_dead_tasks(unsigned int dead_cpu)
         for ( ; ; ) {
                 if (!rq->nr_running)
                         break;
-                next = pick_next_task(rq, rq->curr, rq_clock(rq));
+                update_rq_clock(rq);
+                next = pick_next_task(rq, rq->curr, rq->clock);
                 if (!next)
                         break;
                 migrate_dead(dead_cpu, next);
@@ -5400,7 +5416,8 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
                 rq->migration_thread = NULL;
                 /* Idle task back to normal (off runqueue, low prio) */
                 rq = task_rq_lock(rq->idle, &flags);
-                deactivate_task(rq, rq->idle, 0, rq_clock(rq));
+                update_rq_clock(rq);
+                deactivate_task(rq, rq->idle, 0, rq->clock);
                 rq->idle->static_prio = MAX_PRIO;
                 __setscheduler(rq, rq->idle, SCHED_NORMAL, 0);
                 rq->idle->sched_class = &idle_sched_class;
@@ -6638,8 +6655,10 @@ void normalize_rt_tasks(void)
 #endif
 
                 on_rq = p->se.on_rq;
-                if (on_rq)
-                        deactivate_task(task_rq(p), p, 0, rq_clock(task_rq(p)));
+                if (on_rq) {
+                        update_rq_clock(task_rq(p));
+                        deactivate_task(task_rq(p), p, 0, task_rq(p)->clock);
+                }
                 __setscheduler(rq, p, SCHED_NORMAL, 0);
                 if (on_rq) {
                         activate_task(task_rq(p), p, 0);
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 923bed0b0c42..969f08c8bd34 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -844,7 +844,8 @@ static void check_preempt_curr_fair(struct rq *rq, struct task_struct *p)
         unsigned long gran;
 
         if (unlikely(rt_prio(p->prio))) {
-                update_curr(cfs_rq, rq_clock(rq));
+                update_rq_clock(rq);
+                update_curr(cfs_rq, rq->clock);
                 resched_task(curr);
                 return;
         }
@@ -1063,9 +1064,12 @@ static void set_curr_task_fair(struct rq *rq)
 {
         struct task_struct *curr = rq->curr;
         struct sched_entity *se = &curr->se;
-        u64 now = rq_clock(rq);
+        u64 now;
         struct cfs_rq *cfs_rq;
 
+        update_rq_clock(rq);
+        now = rq->clock;
+
         for_each_sched_entity(se) {
                 cfs_rq = cfs_rq_of(se);
                 set_next_entity(cfs_rq, se, now);