mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-01 06:33:07 +00:00
Code Issues Releases Wiki Activity

x86/intel_pstate: Handle runtime turbo disablement/enablement in frequency invariance

Browse source 
On some platforms such as the Dell XPS 13 laptop the firmware disables turbo
when the machine is disconnected from AC, and viceversa it enables it again
when it's reconnected. In these cases a _PPC ACPI notification is issued.

The scheduler needs to know freq_max for frequency-invariant calculations.
To account for turbo availability to come and go, record freq_max at boot as
if turbo was available and store it in a helper variable. Use a setter
function to swap between freq_base and freq_max every time turbo goes off or on.

Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-7-ggherdovich@suse.cz
This commit is contained in:
Giovanni Gherdovich 2020-01-22 16:16:17 +01:00 committed by Ingo Molnar
parent 298c6f99bf
commit 918229cdd5
3 changed files with 16 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
arch/x86/include/asm/topology.h
View file

@ -211,6 +211,11 @@ static inline long arch_scale_freq_capacity(int cpu)
extern void arch_scale_freq_tick(void);
#define arch_scale_freq_tick arch_scale_freq_tick
extern void arch_set_max_freq_ratio(bool turbo_disabled);
#else
static inline void arch_set_max_freq_ratio(bool turbo_disabled)
{
}
#endif
#endif /* _ASM_X86_TOPOLOGY_H */

15
arch/x86/kernel/smpboot.c
View file

@ -1807,8 +1807,15 @@ DEFINE_STATIC_KEY_FALSE(arch_scale_freq_key);
static DEFINE_PER_CPU(u64, arch_prev_aperf);
static DEFINE_PER_CPU(u64, arch_prev_mperf);
static u64 arch_turbo_freq_ratio = SCHED_CAPACITY_SCALE;
static u64 arch_max_freq_ratio = SCHED_CAPACITY_SCALE;
void arch_set_max_freq_ratio(bool turbo_disabled)
{
arch_max_freq_ratio = turbo_disabled ? SCHED_CAPACITY_SCALE :
arch_turbo_freq_ratio;
}
static bool turbo_disabled(void)
{
u64 misc_en;
@ -1956,10 +1963,7 @@ static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
static bool intel_set_max_freq_ratio(void)
{
u64 base_freq = 1, turbo_freq = 1;
if (turbo_disabled())
goto out;
u64 base_freq, turbo_freq;
if (slv_set_max_freq_ratio(&base_freq, &turbo_freq))
goto out;
@ -1981,8 +1985,9 @@ static bool intel_set_max_freq_ratio(void)
return false;
out:
arch_max_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE,
arch_turbo_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE,
base_freq);
arch_set_max_freq_ratio(turbo_disabled());
return true;
}

1
drivers/cpufreq/intel_pstate.c
View file

@ -922,6 +922,7 @@ static void intel_pstate_update_limits(unsigned int cpu)
*/
if (global.turbo_disabled_mf != global.turbo_disabled) {
global.turbo_disabled_mf = global.turbo_disabled;
arch_set_max_freq_ratio(global.turbo_disabled);
for_each_possible_cpu(cpu)
intel_pstate_update_max_freq(cpu);
} else {