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ACPI: Update the t-state for every affected cpu when t-state is changed

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According to ACPI spec, the _TSD object provides T-state control cross
logical processor dependency information to OSPM. So the t-state
coordination should be considered when T-state for one cpu is changed.

According to ACPI spec, three types of coordination are defined.
SW_ALL, SW_ANY and HW_ALL.

SW_ALL: it means that OSPM needs to initiate T-state transition on
all processors in the domain. It is necessary to call throttling set function
for all affected cpus.

SW_ANY: it means that OSPM may initiate T-state transition on any processor in
the domain.

HW_ALL: Spec only says that hardware will perform the coordination and doesn't
recommend how OSPM coordinate T-state among the affected cpus. So it is treated
as the type of SW_ALL. It means that OSPM needs to initiate t-state transition
on all the processors in the domain.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Zhao Yakui 2008-01-28 13:55:56 +08:00 committed by Len Brown
parent e4aa5cb213
commit 33a2a529f7
1 changed files with 75 additions and 6 deletions
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81
drivers/acpi/processor_throttling.c
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@ -68,7 +68,7 @@ static int acpi_processor_update_tsd_coord(void)
/*
* 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];
@ -988,6 +988,11 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
{
cpumask_t saved_mask;
int ret;
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;
@ -998,12 +1003,76 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
if ((state < 0) || (state > (pr->throttling.state_count - 1)))
return -EINVAL;
/*
* Migrate task to the cpu pointed by pr.
*/
saved_mask = current->cpus_allowed;
set_cpus_allowed(current, cpumask_of_cpu(pr->id));
ret = pr->throttling.acpi_processor_set_throttling(pr, state);
t_state.target_state = state;
p_throttling = &(pr->throttling);
cpus_and(online_throttling_cpus, cpu_online_map,
p_throttling->shared_cpu_map);
/*
* The throttling notifier will be called for every
* affected cpu in order to get one proper T-state.
* The notifier event is THROTTLING_PRECHANGE.
*/
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(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(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);
return ret;