diff options
| -rw-r--r-- | arch/arm/include/asm/barrier.h | 2 | ||||
| -rw-r--r-- | arch/arm/include/asm/processor.h | 6 | ||||
| -rw-r--r-- | arch/arm/kernel/machine_kexec.c | 5 | ||||
| -rw-r--r-- | arch/arm/kernel/smp.c | 4 | ||||
| -rw-r--r-- | arch/arm/mach-omap2/prm_common.c | 4 |
5 files changed, 17 insertions, 4 deletions
diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h index 69772e742a0a..83ae97c049d9 100644 --- a/arch/arm/include/asm/barrier.h +++ b/arch/arm/include/asm/barrier.h @@ -11,6 +11,8 @@ #define sev() __asm__ __volatile__ ("sev" : : : "memory") #define wfe() __asm__ __volatile__ ("wfe" : : : "memory") #define wfi() __asm__ __volatile__ ("wfi" : : : "memory") +#else +#define wfe() do { } while (0) #endif #if __LINUX_ARM_ARCH__ >= 7 diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h index 120f4c9bbfde..57fe73ea0f72 100644 --- a/arch/arm/include/asm/processor.h +++ b/arch/arm/include/asm/processor.h @@ -89,7 +89,11 @@ extern void release_thread(struct task_struct *); unsigned long get_wchan(struct task_struct *p); #if __LINUX_ARM_ARCH__ == 6 || defined(CONFIG_ARM_ERRATA_754327) -#define cpu_relax() smp_mb() +#define cpu_relax() \ + do { \ + smp_mb(); \ + __asm__ __volatile__("nop; nop; nop; nop; nop; nop; nop; nop; nop; nop;"); \ + } while (0) #else #define cpu_relax() barrier() #endif diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index dd2eb5f76b9f..76300f3813e8 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c @@ -91,8 +91,11 @@ void machine_crash_nonpanic_core(void *unused) set_cpu_online(smp_processor_id(), false); atomic_dec(&waiting_for_crash_ipi); - while (1) + + while (1) { cpu_relax(); + wfe(); + } } void crash_smp_send_stop(void) diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 3bf82232b1be..7f0b99e1fff3 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -604,8 +604,10 @@ static void ipi_cpu_stop(unsigned int cpu) local_fiq_disable(); local_irq_disable(); - while (1) + while (1) { cpu_relax(); + wfe(); + } } static DEFINE_PER_CPU(struct completion *, cpu_completion); diff --git a/arch/arm/mach-omap2/prm_common.c b/arch/arm/mach-omap2/prm_common.c index 058a37e6d11c..fd6e0671f957 100644 --- a/arch/arm/mach-omap2/prm_common.c +++ b/arch/arm/mach-omap2/prm_common.c @@ -523,8 +523,10 @@ void omap_prm_reset_system(void) prm_ll_data->reset_system(); - while (1) + while (1) { cpu_relax(); + wfe(); + } } /** |