aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorDmitry Adamushko <dmitry.adamushko@gmail.com>2007-10-15 11:00:07 -0400
committerIngo Molnar <mingo@elte.hu>2007-10-15 11:00:07 -0400
commit30cfdcfc5f180fc21a3dad6ae3b7b2a9ee112186 (patch)
tree7178cde2a1d2b924cc0b66031f4eb02482fe54c2
parent7074badbcb4212d404a243e5c50efeb778ec3fc6 (diff)
sched: do not keep current in the tree and get rid of sched_entity::fair_key
Get rid of 'sched_entity::fair_key'. As a side effect, 'current' is not kept withing the tree for SCHED_NORMAL/BATCH tasks anymore. This simplifies some parts of code (e.g. entity_tick() and yield_task_fair()) and also somewhat optimizes them (e.g. a single update_curr() now vs. dequeue/enqueue() before in entity_tick()). Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r--include/linux/sched.h1
-rw-r--r--kernel/sched.c1
-rw-r--r--kernel/sched_debug.c2
-rw-r--r--kernel/sched_fair.c54
4 files changed, 36 insertions, 22 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 572df1bbaee..f776a30b403 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -891,7 +891,6 @@ struct load_weight {
891 * 6 se->load.weight 891 * 6 se->load.weight
892 */ 892 */
893struct sched_entity { 893struct sched_entity {
894 s64 fair_key;
895 struct load_weight load; /* for load-balancing */ 894 struct load_weight load; /* for load-balancing */
896 struct rb_node run_node; 895 struct rb_node run_node;
897 unsigned int on_rq; 896 unsigned int on_rq;
diff --git a/kernel/sched.c b/kernel/sched.c
index 6d1892192e2..3b104635a8e 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6610,7 +6610,6 @@ void normalize_rt_tasks(void)
6610 6610
6611 read_lock_irq(&tasklist_lock); 6611 read_lock_irq(&tasklist_lock);
6612 do_each_thread(g, p) { 6612 do_each_thread(g, p) {
6613 p->se.fair_key = 0;
6614 p->se.exec_start = 0; 6613 p->se.exec_start = 0;
6615#ifdef CONFIG_SCHEDSTATS 6614#ifdef CONFIG_SCHEDSTATS
6616 p->se.wait_start = 0; 6615 p->se.wait_start = 0;
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index e3b62324ac3..bb34b8188f6 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -38,7 +38,7 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
38 38
39 SEQ_printf(m, "%15s %5d %15Ld %13Ld %5d ", 39 SEQ_printf(m, "%15s %5d %15Ld %13Ld %5d ",
40 p->comm, p->pid, 40 p->comm, p->pid,
41 (long long)p->se.fair_key, 41 (long long)p->se.vruntime,
42 (long long)(p->nvcsw + p->nivcsw), 42 (long long)(p->nvcsw + p->nivcsw),
43 p->prio); 43 p->prio);
44#ifdef CONFIG_SCHEDSTATS 44#ifdef CONFIG_SCHEDSTATS
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 144f3ef9738..b9e426a8a09 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -139,7 +139,7 @@ set_leftmost(struct cfs_rq *cfs_rq, struct rb_node *leftmost)
139static inline s64 139static inline s64
140entity_key(struct cfs_rq *cfs_rq, struct sched_entity *se) 140entity_key(struct cfs_rq *cfs_rq, struct sched_entity *se)
141{ 141{
142 return se->fair_key - cfs_rq->min_vruntime; 142 return se->vruntime - cfs_rq->min_vruntime;
143} 143}
144 144
145/* 145/*
@@ -181,9 +181,6 @@ __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
181 181
182 rb_link_node(&se->run_node, parent, link); 182 rb_link_node(&se->run_node, parent, link);
183 rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline); 183 rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
184 update_load_add(&cfs_rq->load, se->load.weight);
185 cfs_rq->nr_running++;
186 se->on_rq = 1;
187} 184}
188 185
189static void 186static void
@@ -193,9 +190,6 @@ __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
193 set_leftmost(cfs_rq, rb_next(&se->run_node)); 190 set_leftmost(cfs_rq, rb_next(&se->run_node));
194 191
195 rb_erase(&se->run_node, &cfs_rq->tasks_timeline); 192 rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
196 update_load_sub(&cfs_rq->load, se->load.weight);
197 cfs_rq->nr_running--;
198 se->on_rq = 0;
199} 193}
200 194
201static inline struct rb_node *first_fair(struct cfs_rq *cfs_rq) 195static inline struct rb_node *first_fair(struct cfs_rq *cfs_rq)
@@ -341,10 +335,6 @@ static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
341 */ 335 */
342 if (se != cfs_rq->curr) 336 if (se != cfs_rq->curr)
343 update_stats_wait_start(cfs_rq, se); 337 update_stats_wait_start(cfs_rq, se);
344 /*
345 * Update the key:
346 */
347 se->fair_key = se->vruntime;
348} 338}
349 339
350static void 340static void
@@ -392,6 +382,22 @@ update_stats_curr_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
392 * Scheduling class queueing methods: 382 * Scheduling class queueing methods:
393 */ 383 */
394 384
385static void
386account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
387{
388 update_load_add(&cfs_rq->load, se->load.weight);
389 cfs_rq->nr_running++;
390 se->on_rq = 1;
391}
392
393static void
394account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
395{
396 update_load_sub(&cfs_rq->load, se->load.weight);
397 cfs_rq->nr_running--;
398 se->on_rq = 0;
399}
400
395static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) 401static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
396{ 402{
397#ifdef CONFIG_SCHEDSTATS 403#ifdef CONFIG_SCHEDSTATS
@@ -479,7 +485,9 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
479 } 485 }
480 486
481 update_stats_enqueue(cfs_rq, se); 487 update_stats_enqueue(cfs_rq, se);
482 __enqueue_entity(cfs_rq, se); 488 if (se != cfs_rq->curr)
489 __enqueue_entity(cfs_rq, se);
490 account_entity_enqueue(cfs_rq, se);
483} 491}
484 492
485static void 493static void
@@ -498,7 +506,9 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
498 } 506 }
499 } 507 }
500#endif 508#endif
501 __dequeue_entity(cfs_rq, se); 509 if (se != cfs_rq->curr)
510 __dequeue_entity(cfs_rq, se);
511 account_entity_dequeue(cfs_rq, se);
502} 512}
503 513
504/* 514/*
@@ -544,6 +554,10 @@ static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq)
544{ 554{
545 struct sched_entity *se = __pick_next_entity(cfs_rq); 555 struct sched_entity *se = __pick_next_entity(cfs_rq);
546 556
557 /* 'current' is not kept within the tree. */
558 if (se)
559 __dequeue_entity(cfs_rq, se);
560
547 set_next_entity(cfs_rq, se); 561 set_next_entity(cfs_rq, se);
548 562
549 return se; 563 return se;
@@ -560,19 +574,20 @@ static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev)
560 574
561 update_stats_curr_end(cfs_rq, prev); 575 update_stats_curr_end(cfs_rq, prev);
562 576
563 if (prev->on_rq) 577 if (prev->on_rq) {
564 update_stats_wait_start(cfs_rq, prev); 578 update_stats_wait_start(cfs_rq, prev);
579 /* Put 'current' back into the tree. */
580 __enqueue_entity(cfs_rq, prev);
581 }
565 cfs_rq->curr = NULL; 582 cfs_rq->curr = NULL;
566} 583}
567 584
568static void entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) 585static void entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
569{ 586{
570 /* 587 /*
571 * Dequeue and enqueue the task to update its 588 * Update run-time statistics of the 'current'.
572 * position within the tree:
573 */ 589 */
574 dequeue_entity(cfs_rq, curr, 0); 590 update_curr(cfs_rq);
575 enqueue_entity(cfs_rq, curr, 0);
576 591
577 if (cfs_rq->nr_running > 1) 592 if (cfs_rq->nr_running > 1)
578 check_preempt_tick(cfs_rq, curr); 593 check_preempt_tick(cfs_rq, curr);
@@ -749,7 +764,7 @@ static void yield_task_fair(struct rq *rq, struct task_struct *p)
749 /* 764 /*
750 * Minimally necessary key value to be last in the tree: 765 * Minimally necessary key value to be last in the tree:
751 */ 766 */
752 se->fair_key = rightmost->fair_key + 1; 767 se->vruntime = rightmost->vruntime + 1;
753 768
754 if (cfs_rq->rb_leftmost == &se->run_node) 769 if (cfs_rq->rb_leftmost == &se->run_node)
755 cfs_rq->rb_leftmost = rb_next(&se->run_node); 770 cfs_rq->rb_leftmost = rb_next(&se->run_node);
@@ -965,6 +980,7 @@ static void task_new_fair(struct rq *rq, struct task_struct *p)
965 980
966 update_stats_enqueue(cfs_rq, se); 981 update_stats_enqueue(cfs_rq, se);
967 __enqueue_entity(cfs_rq, se); 982 __enqueue_entity(cfs_rq, se);
983 account_entity_enqueue(cfs_rq, se);
968 resched_task(rq->curr); 984 resched_task(rq->curr);
969} 985}
970 986