Adds a routine which can be used to park CPUs (spinning in kernel) when they can't be killed.
Cc: Catalin Marinas <[email protected]> Cc: Mark Rutland <[email protected]> Acked-by: Will Deacon <[email protected]> Signed-off-by: Suzuki K Poulose <[email protected]> --- arch/arm64/include/asm/smp.h | 8 ++++++++ arch/arm64/kernel/cpufeature.c | 5 +---- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index d9c3d6a..53b53a9 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -69,4 +69,12 @@ extern int __cpu_disable(void); extern void __cpu_die(unsigned int cpu); extern void cpu_die(void); +static inline void cpu_park_loop(void) +{ + for (;;) { + wfe(); + wfi(); + } +} + #endif /* ifndef __ASM_SMP_H */ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 5c90aa4..cc4a089 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -842,10 +842,7 @@ static void fail_incapable_cpu(char *cap_type, /* Check if we can park ourselves */ if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die) cpu_ops[cpu]->cpu_die(cpu); - asm( - "1: wfe\n" - " wfi\n" - " b 1b"); + cpu_park_loop(); } /* -- 1.7.9.5
