---

yaml --- r: 43026 b: refs/heads/master c: 72690a2 h: refs/heads/master v: v3
git-mirror · Dec 7, 2006 · 06d3e13 · 06d3e13
1 parent 7b796b3
commit 06d3e13
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Showing 3 changed files with 19 additions and 43 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 63cb683c6ed56a420ba60df6a5b206a44e3f85fe
+refs/heads/master: 72690a21188586022a9e65cb6f1cc8845167555a
diff --git a/trunk/arch/i386/kernel/process.c b/trunk/arch/i386/kernel/process.c
@@ -100,22 +100,18 @@ EXPORT_SYMBOL(enable_hlt);
  */
 void default_idle(void)
 {
-	local_irq_enable();
-
 	if (!hlt_counter && boot_cpu_data.hlt_works_ok) {
 		current_thread_info()->status &= ~TS_POLLING;
 		smp_mb__after_clear_bit();
-		while (!need_resched()) {
-			local_irq_disable();
-			if (!need_resched())
-				safe_halt();
-			else
-				local_irq_enable();
-		}
+		local_irq_disable();
+		if (!need_resched())
+			safe_halt();	/* enables interrupts racelessly */
+		else
+			local_irq_enable();
 		current_thread_info()->status |= TS_POLLING;
 	} else {
-		while (!need_resched())
-			cpu_relax();
+		/* loop is done by the caller */
+		cpu_relax();
 	}
 }
 #ifdef CONFIG_APM_MODULE
@@ -129,14 +125,7 @@ EXPORT_SYMBOL(default_idle);
  */
 static void poll_idle (void)
 {
-	local_irq_enable();
-
-	asm volatile(
-		"2:"
-		"testl %0, %1;"
-		"rep; nop;"
-		"je 2b;"
-		: : "i"(_TIF_NEED_RESCHED), "m" (current_thread_info()->flags));
+	cpu_relax();
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -257,8 +246,7 @@ void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
 static void mwait_idle(void)
 {
 	local_irq_enable();
-	while (!need_resched())
-		mwait_idle_with_hints(0, 0);
+	mwait_idle_with_hints(0, 0);
 }
 
 void __devinit select_idle_routine(const struct cpuinfo_x86 *c)

diff --git a/trunk/arch/x86_64/kernel/process.c b/trunk/arch/x86_64/kernel/process.c
@@ -108,17 +108,15 @@ void exit_idle(void)
  */
 static void default_idle(void)
 {
-	local_irq_enable();
-
 	current_thread_info()->status &= ~TS_POLLING;
 	smp_mb__after_clear_bit();
-	while (!need_resched()) {
-		local_irq_disable();
-		if (!need_resched())
-			safe_halt();
-		else
-			local_irq_enable();
-	}
+	local_irq_disable();
+	if (!need_resched()) {
+		/* Enables interrupts one instruction before HLT.
+		   x86 special cases this so there is no race. */
+		safe_halt();
+	} else
+		local_irq_enable();
 	current_thread_info()->status |= TS_POLLING;
 }
 
@@ -129,16 +127,7 @@ static void default_idle(void)
  */
 static void poll_idle (void)
 {
-	local_irq_enable();
-
-	asm volatile(
-		"2:"
-		"testl %0,%1;"
-		"rep; nop;"
-		"je 2b;"
-		: :
-		"i" (_TIF_NEED_RESCHED),
-		"m" (current_thread_info()->flags));
+	cpu_relax();
 }
 
 void cpu_idle_wait(void)
@@ -257,8 +246,7 @@ void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
 static void mwait_idle(void)
 {
 	local_irq_enable();
-	while (!need_resched())
-		mwait_idle_with_hints(0,0);
+	mwait_idle_with_hints(0,0);
 }
 
 void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)