Merge branch 'misc' into release

Conflicts:
	arch/x86/kernel/process.c

Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 6 insertions, 83 deletions

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index ceb05db59be..b11719ea2f7 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -390,7 +390,8 @@ void default_idle(void)
 EXPORT_SYMBOL(default_idle);
 #endif
 
-bool set_pm_idle_to_default(void)
+#ifdef CONFIG_XEN
+bool xen_set_default_idle(void)
 {
 	bool ret = !!x86_idle;
 
@@ -398,6 +399,7 @@ bool set_pm_idle_to_default(void)
 
 	return ret;
 }
+#endif
 void stop_this_cpu(void *dummy)
 {
 	local_irq_disable();
@@ -407,31 +409,8 @@ void stop_this_cpu(void *dummy)
 	set_cpu_online(smp_processor_id(), false);
 	disable_local_APIC();
 
-	for (;;) {
-		if (hlt_works(smp_processor_id()))
-			halt();
-	}
-}
-
-/* Default MONITOR/MWAIT with no hints, used for default C1 state */
-static void mwait_idle(void)
-{
-	if (!need_resched()) {
-		trace_power_start_rcuidle(POWER_CSTATE, 1, smp_processor_id());
-		trace_cpu_idle_rcuidle(1, smp_processor_id());
-		if (this_cpu_has(X86_FEATURE_CLFLUSH_MONITOR))
-			clflush((void *)&current_thread_info()->flags);
-
-		__monitor((void *)&current_thread_info()->flags, 0, 0);
-		smp_mb();
-		if (!need_resched())
-			__sti_mwait(0, 0);
-		else
-			local_irq_enable();
-		trace_power_end_rcuidle(smp_processor_id());
-		trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
-	} else
-		local_irq_enable();
+	for (;;)
+		halt();
 }
 
 /*
@@ -450,53 +429,6 @@ static void poll_idle(void)
 	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
 }
 
-/*
- * mwait selection logic:
- *
- * It depends on the CPU. For AMD CPUs that support MWAIT this is
- * wrong. Family 0x10 and 0x11 CPUs will enter C1 on HLT. Powersavings
- * then depend on a clock divisor and current Pstate of the core. If
- * all cores of a processor are in halt state (C1) the processor can
- * enter the C1E (C1 enhanced) state. If mwait is used this will never
- * happen.
- *
- * idle=mwait overrides this decision and forces the usage of mwait.
- */
-
-#define MWAIT_INFO			0x05
-#define MWAIT_ECX_EXTENDED_INFO		0x01
-#define MWAIT_EDX_C1			0xf0
-
-int mwait_usable(const struct cpuinfo_x86 *c)
-{
-	u32 eax, ebx, ecx, edx;
-
-	/* Use mwait if idle=mwait boot option is given */
-	if (boot_option_idle_override == IDLE_FORCE_MWAIT)
-		return 1;
-
-	/*
-	 * Any idle= boot option other than idle=mwait means that we must not
-	 * use mwait. Eg: idle=halt or idle=poll or idle=nomwait
-	 */
-	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
-		return 0;
-
-	if (c->cpuid_level < MWAIT_INFO)
-		return 0;
-
-	cpuid(MWAIT_INFO, &eax, &ebx, &ecx, &edx);
-	/* Check, whether EDX has extended info about MWAIT */
-	if (!(ecx & MWAIT_ECX_EXTENDED_INFO))
-		return 1;
-
-	/*
-	 * edx enumeratios MONITOR/MWAIT extensions. Check, whether
-	 * C1  supports MWAIT
-	 */
-	return (edx & MWAIT_EDX_C1);
-}
-
 bool amd_e400_c1e_detected;
 EXPORT_SYMBOL(amd_e400_c1e_detected);
 
@@ -567,13 +499,7 @@ void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 	if (x86_idle)
 		return;
 
-	if (cpu_has(c, X86_FEATURE_MWAIT) && mwait_usable(c)) {
-		/*
-		 * One CPU supports mwait => All CPUs supports mwait
-		 */
-		pr_info("using mwait in idle threads\n");
-		x86_idle = mwait_idle;
-	} else if (cpu_has_amd_erratum(amd_erratum_400)) {
+	if (cpu_has_amd_erratum(amd_erratum_400)) {
 		/* E400: APIC timer interrupt does not wake up CPU from C1e */
 		pr_info("using AMD E400 aware idle routine\n");
 		x86_idle = amd_e400_idle;
@@ -597,9 +523,6 @@ static int __init idle_setup(char *str)
 		pr_info("using polling idle threads\n");
 		x86_idle = poll_idle;
 		boot_option_idle_override = IDLE_POLL;
-	} else if (!strcmp(str, "mwait")) {
-		boot_option_idle_override = IDLE_FORCE_MWAIT;
-		WARN_ONCE(1, "\"idle=mwait\" will be removed in 2012\n");
 	} else if (!strcmp(str, "halt")) {
 		/*
 		 * When the boot option of idle=halt is added, halt is