Commit 05db498a authored by Linus Torvalds's avatar Linus Torvalds

Merge tag 'sched-urgent-2020-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar:
 "Misc fixes:

   - an uclamp accounting fix

   - three frequency invariance fixes and a readability improvement"

* tag 'sched-urgent-2020-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Fix reset-on-fork from RT with uclamp
  x86, sched: Move check for CPU type to caller function
  x86, sched: Don't enable static key when starting secondary CPUs
  x86, sched: Account for CPUs with less than 4 cores in freq. invariance
  x86, sched: Bail out of frequency invariance if base frequency is unknown
parents e1858800 eaf5a92e
......@@ -147,7 +147,7 @@ static inline void smpboot_restore_warm_reset_vector(void)
*((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;
}
static void init_freq_invariance(void);
static void init_freq_invariance(bool secondary);
/*
* Report back to the Boot Processor during boot time or to the caller processor
......@@ -185,7 +185,7 @@ static void smp_callin(void)
*/
set_cpu_sibling_map(raw_smp_processor_id());
init_freq_invariance();
init_freq_invariance(true);
/*
* Get our bogomips.
......@@ -1341,7 +1341,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
set_sched_topology(x86_topology);
set_cpu_sibling_map(0);
init_freq_invariance();
init_freq_invariance(false);
smp_sanity_check();
switch (apic_intr_mode) {
......@@ -1877,9 +1877,6 @@ static bool knl_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq,
int err, i;
u64 msr;
if (!x86_match_cpu(has_knl_turbo_ratio_limits))
return false;
err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
if (err)
return false;
......@@ -1945,18 +1942,23 @@ static bool skx_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, int size)
static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
{
u64 msr;
int err;
err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
if (err)
return false;
err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, turbo_freq);
err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr);
if (err)
return false;
*base_freq = (*base_freq >> 8) & 0xFF; /* max P state */
*turbo_freq = (*turbo_freq >> 24) & 0xFF; /* 4C turbo */
*base_freq = (*base_freq >> 8) & 0xFF; /* max P state */
*turbo_freq = (msr >> 24) & 0xFF; /* 4C turbo */
/* The CPU may have less than 4 cores */
if (!*turbo_freq)
*turbo_freq = msr & 0xFF; /* 1C turbo */
return true;
}
......@@ -1972,7 +1974,8 @@ static bool intel_set_max_freq_ratio(void)
skx_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
goto out;
if (knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
if (x86_match_cpu(has_knl_turbo_ratio_limits) &&
knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
goto out;
if (x86_match_cpu(has_skx_turbo_ratio_limits) &&
......@@ -1985,13 +1988,22 @@ static bool intel_set_max_freq_ratio(void)
return false;
out:
/*
* Some hypervisors advertise X86_FEATURE_APERFMPERF
* but then fill all MSR's with zeroes.
*/
if (!base_freq) {
pr_debug("Couldn't determine cpu base frequency, necessary for scale-invariant accounting.\n");
return false;
}
arch_turbo_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE,
base_freq);
arch_set_max_freq_ratio(turbo_disabled());
return true;
}
static void init_counter_refs(void *arg)
static void init_counter_refs(void)
{
u64 aperf, mperf;
......@@ -2002,18 +2014,25 @@ static void init_counter_refs(void *arg)
this_cpu_write(arch_prev_mperf, mperf);
}
static void init_freq_invariance(void)
static void init_freq_invariance(bool secondary)
{
bool ret = false;
if (smp_processor_id() != 0 || !boot_cpu_has(X86_FEATURE_APERFMPERF))
if (!boot_cpu_has(X86_FEATURE_APERFMPERF))
return;
if (secondary) {
if (static_branch_likely(&arch_scale_freq_key)) {
init_counter_refs();
}
return;
}
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
ret = intel_set_max_freq_ratio();
if (ret) {
on_each_cpu(init_counter_refs, NULL, 1);
init_counter_refs();
static_branch_enable(&arch_scale_freq_key);
} else {
pr_debug("Couldn't determine max cpu frequency, necessary for scale-invariant accounting.\n");
......
......@@ -1232,13 +1232,8 @@ static void uclamp_fork(struct task_struct *p)
return;
for_each_clamp_id(clamp_id) {
unsigned int clamp_value = uclamp_none(clamp_id);
/* By default, RT tasks always get 100% boost */
if (unlikely(rt_task(p) && clamp_id == UCLAMP_MIN))
clamp_value = uclamp_none(UCLAMP_MAX);
uclamp_se_set(&p->uclamp_req[clamp_id], clamp_value, false);
uclamp_se_set(&p->uclamp_req[clamp_id],
uclamp_none(clamp_id), false);
}
}
......
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