scheduler: Fix power saving mode and other minor improvements

src/system/kernel/int.cpp

@@ -685,7 +685,7 @@ void assign_io_interrupt_to_cpu(long vector, int32 newCPU)
 
 	if (newCPU == -1)
 		newCPU = assign_cpu();
-	dprintf_no_syslog("IRQ %ld CPU %" B_PRId32 " -> CPU %" B_PRId32 "\n", vector, oldCPU, newCPU);
+
 	if (newCPU == oldCPU)
 		return;
 

src/system/kernel/scheduler/low_latency.cpp

@@ -19,6 +19,12 @@ switch_to_mode(void)
 }
 
 
+static void
+set_cpu_enabled(int32 /* cpu */, bool /* enabled */)
+{
+}
+
+
 static bool
 has_cache_expired(Thread* thread)
 {
@@ -180,6 +186,7 @@ scheduler_mode_operations gSchedulerLowLatencyMode = {
 	true,
 
 	switch_to_mode,
+	set_cpu_enabled,
 	has_cache_expired,
 	choose_core,
 	should_rebalance,

src/system/kernel/scheduler/power_saving.cpp

@@ -16,6 +16,21 @@ using namespace Scheduler;
 static int32 sSmallTaskCore;
 
 
+static void
+switch_to_mode(void)
+{
+	sSmallTaskCore = -1;
+}
+
+
+static void
+set_cpu_enabled(int32 cpu, bool enabled)
+{
+	if (!enabled)
+		sSmallTaskCore = -1;
+}
+
+
 static bool
 has_cache_expired(Thread* thread)
 {
@@ -31,13 +46,6 @@ has_cache_expired(Thread* thread)
 }
 
 
-static void
-switch_to_mode(void)
-{
-	sSmallTaskCore = -1;
-}
-
-
 static bool
 try_small_task_packing(Thread* thread)
 {
@@ -244,6 +252,7 @@ scheduler_mode_operations gSchedulerPowerSavingMode = {
 	false,
 
 	switch_to_mode,
+	set_cpu_enabled,
 	has_cache_expired,
 	choose_core,
 	should_rebalance,

src/system/kernel/scheduler/scheduler.cpp

@@ -583,9 +583,6 @@ should_rebalance(Thread* thread)
 {
 	ASSERT(!gSingleCore);
 
-	if (thread_is_idle_thread(thread))
-		return false;
-
 	return sCurrentMode->should_rebalance(thread);
 }
 
@@ -600,9 +597,6 @@ compute_cpu_load(int32 cpu)
 	if (oldLoad < 0)
 		return;
 
-	if (gCPUEntries[cpu].fLoad > kVeryHighLoad)
-		sCurrentMode->rebalance_irqs(false);
-
 	if (oldLoad != gCPUEntries[cpu].fLoad) {
 		int32 core = gCPUToCore[cpu];
 
@@ -611,6 +605,9 @@ compute_cpu_load(int32 cpu)
 
 		update_load_heaps(core);
 	}
+
+	if (gCPUEntries[cpu].fLoad > kVeryHighLoad)
+		sCurrentMode->rebalance_irqs(false);
 }
 
 
@@ -1069,8 +1066,7 @@ static inline void
 update_cpu_performance(Thread* thread, int32 thisCore)
 {
 	int32 load = max_c(thread->scheduler_data->load,
-			gCoreEntries[thisCore].fLoad);
+			get_core_load(&gCoreEntries[thisCore]));
-	load /= gCoreEntries[thisCore].fCPUCount;
 	load = min_c(max_c(load, 0), kMaxLoad);
 
 	if (load < kTargetLoad) {
@@ -1369,6 +1365,8 @@ scheduler_set_cpu_enabled(int32 cpu, bool enabled)
 
 	gCPU[cpu].disabled = !enabled;
 
+	sCurrentMode->set_cpu_enabled(cpu, enabled);
+
 	CoreEntry* core = &gCoreEntries[gCPUToCore[cpu]];
 	PackageEntry* package = &gPackageEntries[gCPUToPackage[cpu]];
 

src/system/kernel/scheduler/scheduler_modes.h

@@ -16,6 +16,7 @@ struct scheduler_mode_operations {
 	bool			avoid_boost;
 
 	void			(*switch_to_mode)(void);
+	void			(*set_cpu_enabled)(int32 cpu, bool enabled);
 	bool			(*has_cache_expired)(Thread* thread);
 	int32			(*choose_core)(Thread* thread);
 	bool			(*should_rebalance)(Thread* thread);