#define _COMPONENT ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME("processor_throttling");
+struct throttling_tstate {
+ unsigned int cpu; /* cpu nr */
+ int target_state; /* target T-state */
+};
+
+#define THROTTLING_PRECHANGE (1)
+#define THROTTLING_POSTCHANGE (2)
+
static int acpi_processor_get_throttling(struct acpi_processor *pr);
int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
/*
* Now that we have _TSD data from all CPUs, lets setup T-state
- * coordination among all CPUs.
+ * coordination between all CPUs.
*/
for_each_possible_cpu(i) {
pr = processors[i];
return;
}
+static int acpi_processor_throttling_notifier(unsigned long event, void *data)
+{
+ struct throttling_tstate *p_tstate = data;
+ struct acpi_processor *pr;
+ unsigned int cpu ;
+ int target_state;
+ struct acpi_processor_limit *p_limit;
+ struct acpi_processor_throttling *p_throttling;
+
+ cpu = p_tstate->cpu;
+ pr = processors[cpu];
+ if (!pr) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
+ return 0;
+ }
+ if (!pr->flags.throttling) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
+ "unsupported on CPU %d\n", cpu));
+ return 0;
+ }
+ target_state = p_tstate->target_state;
+ p_throttling = &(pr->throttling);
+ switch (event) {
+ case THROTTLING_PRECHANGE:
+ /*
+ * Prechange event is used to choose one proper t-state,
+ * which meets the limits of thermal, user and _TPC.
+ */
+ p_limit = &pr->limit;
+ if (p_limit->thermal.tx > target_state)
+ target_state = p_limit->thermal.tx;
+ if (p_limit->user.tx > target_state)
+ target_state = p_limit->user.tx;
+ if (pr->throttling_platform_limit > target_state)
+ target_state = pr->throttling_platform_limit;
+ if (target_state >= p_throttling->state_count) {
+ printk(KERN_WARNING
+ "Exceed the limit of T-state \n");
+ target_state = p_throttling->state_count - 1;
+ }
+ p_tstate->target_state = target_state;
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
+ "target T-state of CPU %d is T%d\n",
+ cpu, target_state));
+ break;
+ case THROTTLING_POSTCHANGE:
+ /*
+ * Postchange event is only used to update the
+ * T-state flag of acpi_processor_throttling.
+ */
+ p_throttling->state = target_state;
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
+ "CPU %d is switched to T%d\n",
+ cpu, target_state));
+ break;
+ default:
+ printk(KERN_WARNING
+ "Unsupported Throttling notifier event\n");
+ break;
+ }
+
+ return 0;
+}
+
/*
* _TPC - Throttling Present Capabilities
*/
* Migrate task to the cpu pointed by pr.
*/
saved_mask = current->cpus_allowed;
- set_cpus_allowed(current, cpumask_of_cpu(pr->id));
+ set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id));
ret = pr->throttling.acpi_processor_get_throttling(pr);
/* restore the previous state */
- set_cpus_allowed(current, saved_mask);
+ set_cpus_allowed_ptr(current, &saved_mask);
return ret;
}
int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
{
cpumask_t saved_mask;
- int ret;
+ int ret = 0;
+ unsigned int i;
+ struct acpi_processor *match_pr;
+ struct acpi_processor_throttling *p_throttling;
+ struct throttling_tstate t_state;
+ cpumask_t online_throttling_cpus;
if (!pr)
return -EINVAL;
if ((state < 0) || (state > (pr->throttling.state_count - 1)))
return -EINVAL;
+ saved_mask = current->cpus_allowed;
+ t_state.target_state = state;
+ p_throttling = &(pr->throttling);
+ cpus_and(online_throttling_cpus, cpu_online_map,
+ p_throttling->shared_cpu_map);
/*
- * Migrate task to the cpu pointed by pr.
+ * The throttling notifier will be called for every
+ * affected cpu in order to get one proper T-state.
+ * The notifier event is THROTTLING_PRECHANGE.
*/
- saved_mask = current->cpus_allowed;
- set_cpus_allowed(current, cpumask_of_cpu(pr->id));
- ret = pr->throttling.acpi_processor_set_throttling(pr, state);
+ for_each_cpu_mask(i, online_throttling_cpus) {
+ t_state.cpu = i;
+ acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
+ &t_state);
+ }
+ /*
+ * The function of acpi_processor_set_throttling will be called
+ * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
+ * it is necessary to call it for every affected cpu. Otherwise
+ * it can be called only for the cpu pointed by pr.
+ */
+ if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
+ set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id));
+ ret = p_throttling->acpi_processor_set_throttling(pr,
+ t_state.target_state);
+ } else {
+ /*
+ * When the T-state coordination is SW_ALL or HW_ALL,
+ * it is necessary to set T-state for every affected
+ * cpus.
+ */
+ for_each_cpu_mask(i, online_throttling_cpus) {
+ match_pr = processors[i];
+ /*
+ * If the pointer is invalid, we will report the
+ * error message and continue.
+ */
+ if (!match_pr) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Invalid Pointer for CPU %d\n", i));
+ continue;
+ }
+ /*
+ * If the throttling control is unsupported on CPU i,
+ * we will report the error message and continue.
+ */
+ if (!match_pr->flags.throttling) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Throttling Controll is unsupported "
+ "on CPU %d\n", i));
+ continue;
+ }
+ t_state.cpu = i;
+ set_cpus_allowed_ptr(current, &cpumask_of_cpu(i));
+ ret = match_pr->throttling.
+ acpi_processor_set_throttling(
+ match_pr, t_state.target_state);
+ }
+ }
+ /*
+ * After the set_throttling is called, the
+ * throttling notifier is called for every
+ * affected cpu to update the T-states.
+ * The notifier event is THROTTLING_POSTCHANGE
+ */
+ for_each_cpu_mask(i, online_throttling_cpus) {
+ t_state.cpu = i;
+ acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
+ &t_state);
+ }
/* restore the previous state */
- set_cpus_allowed(current, saved_mask);
+ set_cpus_allowed_ptr(current, &saved_mask);
return ret;
}