diff options
| -rw-r--r-- | arch/x86/kernel/smp.c | 24 | ||||
| -rw-r--r-- | arch/x86/power/hibernate.c | 19 | ||||
| -rw-r--r-- | include/linux/cpu.h | 3 |
3 files changed, 33 insertions, 13 deletions
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c index 18266cc3d98c..b014e6d229f9 100644 --- a/arch/x86/kernel/smp.c +++ b/arch/x86/kernel/smp.c @@ -299,3 +299,27 @@ struct smp_ops smp_ops = { .send_call_func_single_ipi = native_send_call_func_single_ipi, }; EXPORT_SYMBOL_GPL(smp_ops); + +int arch_cpu_rescan_dead_smt_siblings(void) +{ + enum cpuhp_smt_control old = cpu_smt_control; + int ret; + + /* + * If SMT has been disabled and SMT siblings are in HLT, bring them back + * online and offline them again so that they end up in MWAIT proper. + * + * Called with hotplug enabled. + */ + if (old != CPU_SMT_DISABLED && old != CPU_SMT_FORCE_DISABLED) + return 0; + + ret = cpuhp_smt_enable(); + if (ret) + return ret; + + ret = cpuhp_smt_disable(old); + + return ret; +} +EXPORT_SYMBOL_GPL(arch_cpu_rescan_dead_smt_siblings); diff --git a/arch/x86/power/hibernate.c b/arch/x86/power/hibernate.c index a7c23f2a58c9..a2294c1649f6 100644 --- a/arch/x86/power/hibernate.c +++ b/arch/x86/power/hibernate.c @@ -192,7 +192,8 @@ out: int arch_resume_nosmt(void) { - int ret = 0; + int ret; + /* * We reached this while coming out of hibernation. This means * that SMT siblings are sleeping in hlt, as mwait is not safe @@ -206,18 +207,10 @@ int arch_resume_nosmt(void) * Called with hotplug disabled. */ cpu_hotplug_enable(); - if (cpu_smt_control == CPU_SMT_DISABLED || - cpu_smt_control == CPU_SMT_FORCE_DISABLED) { - enum cpuhp_smt_control old = cpu_smt_control; - - ret = cpuhp_smt_enable(); - if (ret) - goto out; - ret = cpuhp_smt_disable(old); - if (ret) - goto out; - } -out: + + ret = arch_cpu_rescan_dead_smt_siblings(); + cpu_hotplug_disable(); + return ret; } diff --git a/include/linux/cpu.h b/include/linux/cpu.h index e6089abc28e2..96a3a0d6a60e 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -120,6 +120,7 @@ extern void cpu_maps_update_begin(void); extern void cpu_maps_update_done(void); int bringup_hibernate_cpu(unsigned int sleep_cpu); void bringup_nonboot_cpus(unsigned int max_cpus); +int arch_cpu_rescan_dead_smt_siblings(void); #else /* CONFIG_SMP */ #define cpuhp_tasks_frozen 0 @@ -134,6 +135,8 @@ static inline void cpu_maps_update_done(void) static inline int add_cpu(unsigned int cpu) { return 0;} +static inline int arch_cpu_rescan_dead_smt_siblings(void) { return 0; } + #endif /* CONFIG_SMP */ extern const struct bus_type cpu_subsys; |