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path: root/drivers/idle/intel_idle.c
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Diffstat (limited to 'drivers/idle/intel_idle.c')
-rw-r--r--drivers/idle/intel_idle.c34
1 files changed, 23 insertions, 11 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 5dc7ea4b6bc4..b2ccce5fb071 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -913,22 +913,29 @@ static __cpuidle int intel_idle(struct cpuidle_device *dev,
struct cpuidle_state *state = &drv->states[index];
unsigned long eax = flg2MWAIT(state->flags);
unsigned int cstate;
-
- cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1;
+ bool uninitialized_var(tick);
+ int cpu = smp_processor_id();
/*
- * NB: if CPUIDLE_FLAG_TLB_FLUSHED is set, this idle transition
- * will probably flush the TLB. It's not guaranteed to flush
- * the TLB, though, so it's not clear that we can do anything
- * useful with this knowledge.
+ * leave_mm() to avoid costly and often unnecessary wakeups
+ * for flushing the user TLB's associated with the active mm.
*/
-
- if (!(lapic_timer_reliable_states & (1 << (cstate))))
- tick_broadcast_enter();
+ if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED)
+ leave_mm(cpu);
+
+ if (!static_cpu_has(X86_FEATURE_ARAT)) {
+ cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) &
+ MWAIT_CSTATE_MASK) + 1;
+ tick = false;
+ if (!(lapic_timer_reliable_states & (1 << (cstate)))) {
+ tick = true;
+ tick_broadcast_enter();
+ }
+ }
mwait_idle_with_hints(eax, ecx);
- if (!(lapic_timer_reliable_states & (1 << (cstate))))
+ if (!static_cpu_has(X86_FEATURE_ARAT) && tick)
tick_broadcast_exit();
return index;
@@ -1060,7 +1067,7 @@ static const struct idle_cpu idle_cpu_dnv = {
};
#define ICPU(model, cpu) \
- { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu }
+ { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&cpu }
static const struct x86_cpu_id intel_idle_ids[] __initconst = {
ICPU(INTEL_FAM6_NEHALEM_EP, idle_cpu_nehalem),
@@ -1124,6 +1131,11 @@ static int __init intel_idle_probe(void)
return -ENODEV;
}
+ if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
+ pr_debug("Please enable MWAIT in BIOS SETUP\n");
+ return -ENODEV;
+ }
+
if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
return -ENODEV;