diff --git a/arch/x86_64/kernel/process.c b/arch/x86_64/kernel/process.c index 0b7b4caa4f74071bfe1797d6e575828241fa5f64..a418ee4c8c62a0d14102b22939dfa8c5b16d0f79 100644 --- a/arch/x86_64/kernel/process.c +++ b/arch/x86_64/kernel/process.c @@ -127,6 +127,7 @@ static void default_idle(void) */ static void poll_idle (void) { + local_irq_enable(); cpu_relax(); } @@ -208,6 +209,12 @@ void cpu_idle (void) idle = default_idle; if (cpu_is_offline(smp_processor_id())) play_dead(); + /* + * Idle routines should keep interrupts disabled + * from here on, until they go to idle. + * Otherwise, idle callbacks can misfire. + */ + local_irq_disable(); enter_idle(); idle(); /* In many cases the interrupt that ended idle @@ -245,8 +252,16 @@ void mwait_idle_with_hints(unsigned long eax, unsigned long ecx) /* Default MONITOR/MWAIT with no hints, used for default C1 state */ static void mwait_idle(void) { - local_irq_enable(); - mwait_idle_with_hints(0,0); + if (!need_resched()) { + __monitor((void *)¤t_thread_info()->flags, 0, 0); + smp_mb(); + if (!need_resched()) + __sti_mwait(0, 0); + else + local_irq_enable(); + } else { + local_irq_enable(); + } } void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c) diff --git a/include/asm-x86_64/processor.h b/include/asm-x86_64/processor.h index cef17e0f828cc5d0080cf967d11e80a228f4d18b..76552d72804c6368ed210fd02811c0f9608308e7 100644 --- a/include/asm-x86_64/processor.h +++ b/include/asm-x86_64/processor.h @@ -475,6 +475,14 @@ static inline void __mwait(unsigned long eax, unsigned long ecx) : :"a" (eax), "c" (ecx)); } +static inline void __sti_mwait(unsigned long eax, unsigned long ecx) +{ + /* "mwait %eax,%ecx;" */ + asm volatile( + "sti; .byte 0x0f,0x01,0xc9;" + : :"a" (eax), "c" (ecx)); +} + extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx); #define stack_current() \