Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
+35
-21
+33
-14
arch/x86/kernel/smpboot.c
+33
-14
arch/x86/kernel/smpboot.c
···
147
147
*((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;
148
148
}
149
149
150
-
static void init_freq_invariance(void);
150
+
static void init_freq_invariance(bool secondary);
151
151
152
152
/*
153
153
* Report back to the Boot Processor during boot time or to the caller processor
···
185
185
*/
186
186
set_cpu_sibling_map(raw_smp_processor_id());
187
187
188
-
init_freq_invariance();
188
+
init_freq_invariance(true);
189
189
190
190
/*
191
191
* Get our bogomips.
···
1341
1341
set_sched_topology(x86_topology);
1342
1342
1343
1343
set_cpu_sibling_map(0);
1344
-
init_freq_invariance();
1344
+
init_freq_invariance(false);
1345
1345
smp_sanity_check();
1346
1346
1347
1347
switch (apic_intr_mode) {
···
1877
1877
int err, i;
1878
1878
u64 msr;
1879
1879
1880
-
if (!x86_match_cpu(has_knl_turbo_ratio_limits))
1881
-
return false;
1882
-
1883
1880
err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
1884
1881
if (err)
1885
1882
return false;
···
1942
1945
1943
1946
static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
1944
1947
{
1948
+
u64 msr;
1945
1949
int err;
1946
1950
1947
1951
err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
1948
1952
if (err)
1949
1953
return false;
1950
1954
1951
-
err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, turbo_freq);
1955
+
err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr);
1952
1956
if (err)
1953
1957
return false;
1954
1958
1955
-
*base_freq = (*base_freq >> 8) & 0xFF; /* max P state */
1956
-
*turbo_freq = (*turbo_freq >> 24) & 0xFF; /* 4C turbo */
1959
+
*base_freq = (*base_freq >> 8) & 0xFF; /* max P state */
1960
+
*turbo_freq = (msr >> 24) & 0xFF; /* 4C turbo */
1961
+
1962
+
/* The CPU may have less than 4 cores */
1963
+
if (!*turbo_freq)
1964
+
*turbo_freq = msr & 0xFF; /* 1C turbo */
1957
1965
1958
1966
return true;
1959
1967
}
···
1974
1972
skx_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
1975
1973
goto out;
1976
1974
1977
-
if (knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
1975
+
if (x86_match_cpu(has_knl_turbo_ratio_limits) &&
1976
+
knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
1978
1977
goto out;
1979
1978
1980
1979
if (x86_match_cpu(has_skx_turbo_ratio_limits) &&
···
1988
1985
return false;
1989
1986
1990
1987
out:
1988
+
/*
1989
+
* Some hypervisors advertise X86_FEATURE_APERFMPERF
1990
+
* but then fill all MSR's with zeroes.
1991
+
*/
1992
+
if (!base_freq) {
1993
+
pr_debug("Couldn't determine cpu base frequency, necessary for scale-invariant accounting.\n");
1994
+
return false;
1995
+
}
1996
+
1991
1997
arch_turbo_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE,
1992
1998
base_freq);
1993
1999
arch_set_max_freq_ratio(turbo_disabled());
1994
2000
return true;
1995
2001
}
1996
2002
1997
-
static void init_counter_refs(void *arg)
2003
+
static void init_counter_refs(void)
1998
2004
{
1999
2005
u64 aperf, mperf;
2000
2006
···
2014
2002
this_cpu_write(arch_prev_mperf, mperf);
2015
2003
}
2016
2004
2017
-
static void init_freq_invariance(void)
2005
+
static void init_freq_invariance(bool secondary)
2018
2006
{
2019
2007
bool ret = false;
2020
2008
2021
-
if (smp_processor_id() != 0 || !boot_cpu_has(X86_FEATURE_APERFMPERF))
2009
+
if (!boot_cpu_has(X86_FEATURE_APERFMPERF))
2022
2010
return;
2011
+
2012
+
if (secondary) {
2013
+
if (static_branch_likely(&arch_scale_freq_key)) {
2014
+
init_counter_refs();
2015
+
}
2016
+
return;
2017
+
}
2023
2018
2024
2019
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
2025
2020
ret = intel_set_max_freq_ratio();
2026
2021
2027
2022
if (ret) {
2028
-
on_each_cpu(init_counter_refs, NULL, 1);
2023
+
init_counter_refs();
2029
2024
static_branch_enable(&arch_scale_freq_key);
2030
2025
} else {
2031
2026
pr_debug("Couldn't determine max cpu frequency, necessary for scale-invariant accounting.\n");
+2
-7
kernel/sched/core.c
+2
-7
kernel/sched/core.c
···
1232
1232
return;
1233
1233
1234
1234
for_each_clamp_id(clamp_id) {
1235
-
unsigned int clamp_value = uclamp_none(clamp_id);
1236
-
1237
-
/* By default, RT tasks always get 100% boost */
1238
-
if (unlikely(rt_task(p) && clamp_id == UCLAMP_MIN))
1239
-
clamp_value = uclamp_none(UCLAMP_MAX);
1240
-
1241
-
uclamp_se_set(&p->uclamp_req[clamp_id], clamp_value, false);
1235
+
uclamp_se_set(&p->uclamp_req[clamp_id],
1236
+
uclamp_none(clamp_id), false);
1242
1237
}
1243
1238
}
1244
1239