Tidy up left over smpnice code after changes introduced with CFS

PATCH In review Peter Williams 2 participants 2 messages Aug 2, 2007

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Peter Williams

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2007-08-02 09:27 UTC #0 lore raw

PATCH 1/1 Tidy up left over smpnice code after changes introduced with CFS

1. The only place that RTPRIO_TO_LOAD_WEIGHT() is used is in the call to move_tasks() in the function active_load_balance() and its purpose here is just to make sure that the load to be moved is big enough to ensure that exactly one task is moved (if there's one available). This can be accomplished by using ULONG_MAX instead and this allows RTPRIO_TO_LOAD_WEIGHT() to be deleted.

2. This, in turn, allows PRIO_TO_LOAD_WEIGHT() to be deleted.

3. This allows load_weight() to be deleted which allows TIME_SLICE_NICE_ZERO to be deleted along with the comment above it.

Signed-off-by Peter Williams <[email protected]>

Signature · 4 lines

Peter Williams                                   [email protected]

"Learning, n. The kind of ignorance distinguishing the studious."
 -- Ambrose Bierce

kernel/sched.c +1 ~~-15~~

diff -r 622a128d084b kernel/sched.c
@@ -727,19 +727,6 @@ static void update_curr_load(struct rq *
  * slice expiry etc.
  */
 
-/*
- * Assume: static_prio_timeslice(NICE_TO_PRIO(0)) == DEF_TIMESLICE
- * If static_prio_timeslice() is ever changed to break this assumption then
- * this code will need modification
- */
-#define TIME_SLICE_NICE_ZERO DEF_TIMESLICE
-#define load_weight(lp) \
-	(((lp) * SCHED_LOAD_SCALE) / TIME_SLICE_NICE_ZERO)
-#define PRIO_TO_LOAD_WEIGHT(prio) \
-	load_weight(static_prio_timeslice(prio))
-#define RTPRIO_TO_LOAD_WEIGHT(rp) \
-	(PRIO_TO_LOAD_WEIGHT(MAX_RT_PRIO) + load_weight(rp))
-
 #define WEIGHT_IDLEPRIO		2
 #define WMULT_IDLEPRIO		(1 << 31)

@@ -2906,8 +2893,7 @@ static void active_load_balance(struct r
 		schedstat_inc(sd, alb_cnt);
 
 		if (move_tasks(target_rq, target_cpu, busiest_rq, 1,
-			       RTPRIO_TO_LOAD_WEIGHT(100), sd, CPU_IDLE,
-			       NULL))
+			       ULONG_MAX, sd, CPU_IDLE, NULL))
 			schedstat_inc(sd, alb_pushed);
 		else
 			schedstat_inc(sd, alb_failed);

Ingo Molnar

2007-08-02 10:29 UTC #1 lore raw

Quoted 11 lines · Peter Williams

1. The only place that RTPRIO_TO_LOAD_WEIGHT() is used is in the call to move_tasks() in the function active_load_balance() and its purpose here is just to make sure that the load to be moved is big enough to ensure that exactly one task is moved (if there's one available). This can be accomplished by using ULONG_MAX instead and this allows RTPRIO_TO_LOAD_WEIGHT() to be deleted.
2. This, in turn, allows PRIO_TO_LOAD_WEIGHT() to be deleted.
3. This allows load_weight() to be deleted which allows TIME_SLICE_NICE_ZERO to be deleted along with the comment above it.

thanks, i've added this to my tree.

Ingo