diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index 29572debc65d..360a74e6add0 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -427,8 +427,13 @@ static int acpi_cpu_soft_notify(struct notifier_block *nfb, if (action == CPU_ONLINE && pr) { acpi_processor_ppc_has_changed(pr, 0); acpi_processor_cst_has_changed(pr); + acpi_processor_reevaluate_tstate(pr, action); acpi_processor_tstate_has_changed(pr); } + if (action == CPU_DEAD && pr) { + /* invalidate the flag.throttling after one CPU is offline */ + acpi_processor_reevaluate_tstate(pr, action); + } return NOTIFY_OK; } diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 4a0eec5dd24a..fa84e9744330 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -365,6 +365,58 @@ int acpi_processor_tstate_has_changed(struct acpi_processor *pr) return acpi_processor_set_throttling(pr, target_state, false); } +/* + * This function is used to reevaluate whether the T-state is valid + * after one CPU is onlined/offlined. + * It is noted that it won't reevaluate the following properties for + * the T-state. + * 1. Control method. + * 2. the number of supported T-state + * 3. TSD domain + */ +void acpi_processor_reevaluate_tstate(struct acpi_processor *pr, + unsigned long action) +{ + int result = 0; + + if (action == CPU_DEAD) { + /* When one CPU is offline, the T-state throttling + * will be invalidated. + */ + pr->flags.throttling = 0; + return; + } + /* the following is to recheck whether the T-state is valid for + * the online CPU + */ + if (!pr->throttling.state_count) { + /* If the number of T-state is invalid, it is + * invalidated. + */ + pr->flags.throttling = 0; + return; + } + pr->flags.throttling = 1; + + /* Disable throttling (if enabled). We'll let subsequent + * policy (e.g.thermal) decide to lower performance if it + * so chooses, but for now we'll crank up the speed. + */ + + result = acpi_processor_get_throttling(pr); + if (result) + goto end; + + if (pr->throttling.state) { + result = acpi_processor_set_throttling(pr, 0, false); + if (result) + goto end; + } + +end: + if (result) + pr->flags.throttling = 0; +} /* * _PTC - Processor Throttling Control (and status) register location */ @@ -872,7 +924,11 @@ static int acpi_processor_get_throttling(struct acpi_processor *pr) */ cpumask_copy(saved_mask, ¤t->cpus_allowed); /* FIXME: use work_on_cpu() */ - set_cpus_allowed_ptr(current, cpumask_of(pr->id)); + if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) { + /* Can't migrate to the target pr->id CPU. Exit */ + free_cpumask_var(saved_mask); + return -ENODEV; + } ret = pr->throttling.acpi_processor_get_throttling(pr); /* restore the previous state */ set_cpus_allowed_ptr(current, saved_mask); @@ -1047,6 +1103,14 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, return -ENOMEM; } + if (cpu_is_offline(pr->id)) { + /* + * the cpu pointed by pr->id is offline. Unnecessary to change + * the throttling state any more. + */ + return -ENODEV; + } + cpumask_copy(saved_mask, ¤t->cpus_allowed); t_state.target_state = state; p_throttling = &(pr->throttling); @@ -1070,7 +1134,11 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, */ if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) { /* FIXME: use work_on_cpu() */ - set_cpus_allowed_ptr(current, cpumask_of(pr->id)); + if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) { + /* Can't migrate to the pr->id CPU. Exit */ + ret = -ENODEV; + goto exit; + } ret = p_throttling->acpi_processor_set_throttling(pr, t_state.target_state, force); } else { @@ -1102,7 +1170,8 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, } t_state.cpu = i; /* FIXME: use work_on_cpu() */ - set_cpus_allowed_ptr(current, cpumask_of(i)); + if (set_cpus_allowed_ptr(current, cpumask_of(i))) + continue; ret = match_pr->throttling. acpi_processor_set_throttling( match_pr, t_state.target_state, force); @@ -1122,6 +1191,7 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, /* restore the previous state */ /* FIXME: use work_on_cpu() */ set_cpus_allowed_ptr(current, saved_mask); +exit: free_cpumask_var(online_throttling_cpus); free_cpumask_var(saved_mask); return ret; diff --git a/include/acpi/processor.h b/include/acpi/processor.h index 1b62102fbb67..55192ac0cede 100644 --- a/include/acpi/processor.h +++ b/include/acpi/processor.h @@ -324,6 +324,12 @@ int acpi_processor_tstate_has_changed(struct acpi_processor *pr); int acpi_processor_get_throttling_info(struct acpi_processor *pr); extern int acpi_processor_set_throttling(struct acpi_processor *pr, int state, bool force); +/* + * Reevaluate whether the T-state is invalid after one cpu is + * onlined/offlined. In such case the flags.throttling will be updated. + */ +extern void acpi_processor_reevaluate_tstate(struct acpi_processor *pr, + unsigned long action); extern const struct file_operations acpi_processor_throttling_fops; extern void acpi_processor_throttling_init(void); /* in processor_idle.c */