10/13
Remove the very aggressive idle stuff that has recently gone into
2.6 - it is going against the direction we are trying to go. Hopefully
we can regain performance through other methods.
Signed-off-by: Nick Piggin <[EMAIL PROTECTED]>
Index: linux-2.6/include/asm-i386/topology.h
===================================================================
--- linux-2.6.orig/include/asm-i386/topology.h 2005-02-24 17:39:06.805011214 +1100
+++ linux-2.6/include/asm-i386/topology.h 2005-02-24 17:39:07.320947536 +1100
@@ -85,7 +85,6 @@
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_EXEC \
| SD_BALANCE_NEWIDLE \
- | SD_WAKE_IDLE \
| SD_WAKE_BALANCE, \
.last_balance = jiffies, \
.balance_interval = 1, \
Index: linux-2.6/include/asm-x86_64/topology.h
===================================================================
--- linux-2.6.orig/include/asm-x86_64/topology.h 2005-02-24 17:39:06.805011214 +1100
+++ linux-2.6/include/asm-x86_64/topology.h 2005-02-24 17:43:37.503607973 +1100
@@ -58,7 +58,6 @@
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_NEWIDLE \
| SD_BALANCE_EXEC \
- | SD_WAKE_IDLE \
| SD_WAKE_BALANCE, \
.last_balance = jiffies, \
.balance_interval = 1, \
Index: linux-2.6/include/linux/topology.h
===================================================================
--- linux-2.6.orig/include/linux/topology.h 2005-02-24 17:39:06.806011090 +1100
+++ linux-2.6/include/linux/topology.h 2005-02-24 17:43:37.503607973 +1100
@@ -124,7 +124,6 @@
| SD_BALANCE_NEWIDLE \
| SD_BALANCE_EXEC \
| SD_WAKE_AFFINE \
- | SD_WAKE_IDLE \
| SD_WAKE_BALANCE, \
.last_balance = jiffies, \
.balance_interval = 1, \
Index: linux-2.6/kernel/sched.c
===================================================================
--- linux-2.6.orig/kernel/sched.c 2005-02-24 17:39:07.057979992 +1100
+++ linux-2.6/kernel/sched.c 2005-02-24 17:43:37.504607850 +1100
@@ -412,22 +412,6 @@
return rq;
}
-#ifdef CONFIG_SCHED_SMT
-static int cpu_and_siblings_are_idle(int cpu)
-{
- int sib;
- for_each_cpu_mask(sib, cpu_sibling_map[cpu]) {
- if (idle_cpu(sib))
- continue;
- return 0;
- }
-
- return 1;
-}
-#else
-#define cpu_and_siblings_are_idle(A) idle_cpu(A)
-#endif
-
#ifdef CONFIG_SCHEDSTATS
/*
* Called when a process is dequeued from the active array and given
@@ -1650,16 +1634,15 @@
/*
* Aggressive migration if:
- * 1) the [whole] cpu is idle, or
+ * 1) task is cache cold, or
* 2) too many balance attempts have failed.
*/
- if (cpu_and_siblings_are_idle(this_cpu) || \
- sd->nr_balance_failed > sd->cache_nice_tries)
+ if (sd->nr_balance_failed > sd->cache_nice_tries)
return 1;
if (task_hot(p, rq->timestamp_last_tick, sd))
- return 0;
+ return 0;
return 1;
}
@@ -2131,7 +2114,7 @@
if (cpu_isset(cpu, visited_cpus))
continue;
cpu_set(cpu, visited_cpus);
- if (!cpu_and_siblings_are_idle(cpu) || cpu == busiest_cpu)
+ if (cpu == busiest_cpu)
continue;
target_rq = cpu_rq(cpu);
