* [PATCH v3 1/3] x86, sched: Calculate frequency invariance for AMD systems
2020-11-10 20:05 [PATCH v3 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
@ 2020-11-10 20:05 ` Giovanni Gherdovich
2020-11-10 20:05 ` [PATCH v3 2/3] x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC Giovanni Gherdovich
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 20:05 UTC (permalink / raw)
To: Borislav Petkov, Thomas Gleixner, Ingo Molnar, Peter Zijlstra,
Len Brown, Rafael J . Wysocki
Cc: Jon Grimm, Nathan Fontenot, Yazen Ghannam, Thomas Lendacky,
Mel Gorman, Pu Wen, Viresh Kumar, Juri Lelli, Vincent Guittot,
Dietmar Eggemann, Doug Smythies, x86, linux-pm, linux-kernel,
linux-acpi, Nathan Fontenot, Giovanni Gherdovich
From: Nathan Fontenot <nathan.fontenot@amd.com>
This is the first pass in creating the ability to calculate the
frequency invariance on AMD systems. This approach uses the CPPC
highest performance and nominal performance values that range from
0 - 255 instead of a high and base frquency. This is because we do
not have the ability on AMD to get a highest frequency value.
On AMD systems the highest performance and nominal performance
vaues do correspond to the highest and base frequencies for the system
so using them should produce an appropriate ratio but some tweaking
is likely necessary.
Due to CPPC being initialized later in boot than when the frequency
invariant calculation is currently made, I had to create a callback
from the CPPC init code to do the calculation after we have CPPC
data.
Signed-off-by: Nathan Fontenot <nathan.fontenot@amd.com>
[ ggherdovich@suse.cz: made safe under CPU hotplug ]
Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
---
arch/x86/include/asm/topology.h | 8 ++++
arch/x86/kernel/smpboot.c | 76 ++++++++++++++++++++++++++++++---
drivers/acpi/cppc_acpi.c | 3 ++
3 files changed, 82 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index f4234575f3fd..9799d4da282d 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -218,4 +218,12 @@ static inline void arch_set_max_freq_ratio(bool turbo_disabled)
}
#endif
+#ifdef CONFIG_ACPI
+void init_freq_invariance_cppc(void);
+#else
+static inline void init_freq_invariance_cppc(void)
+{
+}
+#endif
+
#endif /* _ASM_X86_TOPOLOGY_H */
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index de776b2e6046..da410bd36af6 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -82,6 +82,10 @@
#include <asm/hw_irq.h>
#include <asm/stackprotector.h>
+#ifdef CONFIG_ACPI
+#include <acpi/cppc_acpi.h>
+#endif
+
/* representing HT siblings of each logical CPU */
DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map);
EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
@@ -148,7 +152,7 @@ static inline void smpboot_restore_warm_reset_vector(void)
*((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;
}
-static void init_freq_invariance(bool secondary);
+static void init_freq_invariance(bool secondary, bool cppc_ready);
/*
* Report back to the Boot Processor during boot time or to the caller processor
@@ -186,7 +190,7 @@ static void smp_callin(void)
*/
set_cpu_sibling_map(raw_smp_processor_id());
- init_freq_invariance(true);
+ init_freq_invariance(true, false);
/*
* Get our bogomips.
@@ -1340,7 +1344,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
set_sched_topology(x86_topology);
set_cpu_sibling_map(0);
- init_freq_invariance(false);
+ init_freq_invariance(false, false);
smp_sanity_check();
switch (apic_intr_mode) {
@@ -2027,6 +2031,46 @@ static bool intel_set_max_freq_ratio(void)
return true;
}
+#ifdef CONFIG_ACPI
+static bool amd_set_max_freq_ratio(void)
+{
+ struct cppc_perf_caps perf_caps;
+ u64 highest_perf, nominal_perf;
+ u64 perf_ratio;
+ int rc;
+
+ rc = cppc_get_perf_caps(0, &perf_caps);
+ if (rc) {
+ pr_debug("Could not retrieve perf counters (%d)\n", rc);
+ return false;
+ }
+
+ highest_perf = perf_caps.highest_perf;
+ nominal_perf = perf_caps.nominal_perf;
+
+ if (!highest_perf || !nominal_perf) {
+ pr_debug("Could not retrieve highest or nominal performance\n");
+ return false;
+ }
+
+ perf_ratio = div_u64(highest_perf * SCHED_CAPACITY_SCALE, nominal_perf);
+ if (!perf_ratio) {
+ pr_debug("Non-zero highest/nominal perf values led to a 0 ratio\n");
+ return false;
+ }
+
+ arch_turbo_freq_ratio = perf_ratio;
+ arch_set_max_freq_ratio(false);
+
+ return true;
+}
+#else
+static bool amd_set_max_freq_ratio(void)
+{
+ return false;
+}
+#endif
+
static void init_counter_refs(void)
{
u64 aperf, mperf;
@@ -2038,7 +2082,7 @@ static void init_counter_refs(void)
this_cpu_write(arch_prev_mperf, mperf);
}
-static void init_freq_invariance(bool secondary)
+static void init_freq_invariance(bool secondary, bool cppc_ready)
{
bool ret = false;
@@ -2054,6 +2098,12 @@ static void init_freq_invariance(bool secondary)
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
ret = intel_set_max_freq_ratio();
+ else if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+ if (!cppc_ready) {
+ return;
+ }
+ ret = amd_set_max_freq_ratio();
+ }
if (ret) {
init_counter_refs();
@@ -2063,6 +2113,22 @@ static void init_freq_invariance(bool secondary)
}
}
+#ifdef CONFIG_ACPI
+static DEFINE_MUTEX(freq_invariance_lock);
+
+void init_freq_invariance_cppc(void)
+{
+ static bool secondary;
+
+ mutex_lock(&freq_invariance_lock);
+
+ init_freq_invariance(secondary, true);
+ secondary = true;
+
+ mutex_unlock(&freq_invariance_lock);
+}
+#endif
+
static void disable_freq_invariance_workfn(struct work_struct *work)
{
static_branch_disable(&arch_scale_freq_key);
@@ -2112,7 +2178,7 @@ void arch_scale_freq_tick(void)
schedule_work(&disable_freq_invariance_work);
}
#else
-static inline void init_freq_invariance(bool secondary)
+static inline void init_freq_invariance(bool secondary, bool cppc_ready)
{
}
#endif /* CONFIG_X86_64 */
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 7a99b19bb893..368b13cb975d 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -39,6 +39,7 @@
#include <linux/ktime.h>
#include <linux/rwsem.h>
#include <linux/wait.h>
+#include <linux/topology.h>
#include <acpi/cppc_acpi.h>
@@ -850,6 +851,8 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
goto out_free;
}
+ init_freq_invariance_cppc();
+
kfree(output.pointer);
return 0;
--
2.26.2
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v3 2/3] x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC
2020-11-10 20:05 [PATCH v3 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
2020-11-10 20:05 ` [PATCH v3 1/3] x86, sched: Calculate frequency invariance for AMD systems Giovanni Gherdovich
@ 2020-11-10 20:05 ` Giovanni Gherdovich
2020-11-10 20:05 ` [PATCH v3 3/3] x86: Print ratio freq_max/freq_base used in frequency invariance calculations Giovanni Gherdovich
2020-11-12 18:33 ` [PATCH v3 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
3 siblings, 0 replies; 5+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 20:05 UTC (permalink / raw)
To: Borislav Petkov, Thomas Gleixner, Ingo Molnar, Peter Zijlstra,
Len Brown, Rafael J . Wysocki
Cc: Jon Grimm, Nathan Fontenot, Yazen Ghannam, Thomas Lendacky,
Mel Gorman, Pu Wen, Viresh Kumar, Juri Lelli, Vincent Guittot,
Dietmar Eggemann, Doug Smythies, x86, linux-pm, linux-kernel,
linux-acpi, Giovanni Gherdovich
Frequency invariant accounting calculations need the ratio
freq_curr/freq_max, but freq_max is unknown as it depends on dynamic power
allocation between cores: AMD EPYC CPUs implement "Core Performance Boost".
Three candidates are considered to estimate this value:
- maximum non-boost frequency
- maximum boost frequency
- the mid point between the above two
Experimental data on an AMD EPYC Zen2 machine slightly favors the third
option, which is applied with this patch.
The analysis uses the ondemand cpufreq governor as baseline, and compares
it with schedutil in a number of configurations. Using the freq_max value
described above offers a moderate advantage in performance and efficiency:
sugov-max (freq_max=max_boost) performs the worst on tbench: less
throughput and reduced efficiency than the other invariant-schedutil
options (see "Data Overview" below). Consider that tbench is generally a
problematic case as no schedutil version currently is better than ondemand.
sugov-P0 (freq_max=max_P) is the worst on dbench, while the other sugov's
can surpass ondemand with less filesystem latency and slightly increased
efficiency.
1. DATA OVERVIEW
2. DETAILED PERFORMANCE TABLES
3. POWER CONSUMPTION TABLE
1. DATA OVERVIEW
================
sugov-noinv : non-invariant schedutil governor
sugov-max : invariant schedutil, freq_max=max_boost
sugov-mid : invariant schedutil, freq_max=midpoint
sugov-P0 : invariant schedutil, freq_max=max_P
perfgov : performance governor
driver : acpi_cpufreq
machine : AMD EPYC 7742 (Zen2, aka "Rome"), dual socket,
128 cores / 256 threads, SATA SSD storage, 250G of memory,
XFS filesystem
Benchmarks are described in the next section.
Tilde (~) means the value is the same as baseline.
-------------------------------------------------------------------------------------
ondemand perfgov sugov-noinv sugov-max sugov-mid sugov-P0 better if
-------------------------------------------------------------------------------------
PERFORMANCE RATIOS
tbench 1.00 1.44 0.90 0.87 0.93 0.93 higher
dbench 1.00 0.91 0.95 0.94 0.94 1.06 lower
kernbench 1.00 0.93 ~ ~ ~ 0.97 lower
gitsource 1.00 0.66 0.97 0.96 ~ 0.95 lower
-------------------------------------------------------------------------------------
PERFORMANCE-PER-WATT RATIOS
tbench 1.00 1.16 0.84 0.84 0.88 0.85 higher
dbench 1.00 1.03 1.02 1.02 1.02 0.93 higher
kernbench 1.00 1.05 ~ ~ ~ ~ higher
gitsource 1.00 1.46 1.04 1.04 ~ 1.05 higher
2. DETAILED PERFORMANCE TABLES
==============================
Benchmark : tbench4 (i.e. dbench4 over the network, actually loopback)
Varying parameter : number of clients
Unit : MB/sec (higher is better)
5.9.0-ondemand (BASELINE) 5.9.0-perfgov 5.9.0-sugov-noinv
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean 1 427.19 +- 0.16% ( ) 778.35 +- 0.10% ( 82.20%) 346.92 +- 0.14% ( -18.79%)
Hmean 2 853.82 +- 0.09% ( ) 1536.23 +- 0.03% ( 79.93%) 694.36 +- 0.05% ( -18.68%)
Hmean 4 1657.54 +- 0.12% ( ) 2938.18 +- 0.12% ( 77.26%) 1362.81 +- 0.11% ( -17.78%)
Hmean 8 3301.87 +- 0.06% ( ) 5679.10 +- 0.04% ( 72.00%) 2693.35 +- 0.04% ( -18.43%)
Hmean 16 6139.65 +- 0.05% ( ) 9498.81 +- 0.04% ( 54.71%) 4889.97 +- 0.17% ( -20.35%)
Hmean 32 11170.28 +- 0.09% ( ) 17393.25 +- 0.08% ( 55.71%) 9104.55 +- 0.09% ( -18.49%)
Hmean 64 19322.97 +- 0.17% ( ) 31573.91 +- 0.08% ( 63.40%) 18552.52 +- 0.40% ( -3.99%)
Hmean 128 30383.71 +- 0.11% ( ) 37416.91 +- 0.15% ( 23.15%) 25938.70 +- 0.41% ( -14.63%)
Hmean 256 31143.96 +- 0.41% ( ) 30908.76 +- 0.88% ( -0.76%) 29754.32 +- 0.24% ( -4.46%)
Hmean 512 30858.49 +- 0.26% ( ) 38524.60 +- 1.19% ( 24.84%) 42080.39 +- 0.56% ( 36.37%)
Hmean 1024 39187.37 +- 0.19% ( ) 36213.86 +- 0.26% ( -7.59%) 39555.98 +- 0.12% ( 0.94%)
5.9.0-sugov-max 5.9.0-sugov-mid 5.9.0-sugov-P0
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean 1 352.59 +- 1.03% ( -17.46%) 352.08 +- 0.75% ( -17.58%) 352.31 +- 1.48% ( -17.53%)
Hmean 2 697.32 +- 0.08% ( -18.33%) 700.16 +- 0.20% ( -18.00%) 696.79 +- 0.06% ( -18.39%)
Hmean 4 1369.88 +- 0.04% ( -17.35%) 1369.72 +- 0.07% ( -17.36%) 1365.91 +- 0.05% ( -17.59%)
Hmean 8 2696.79 +- 0.04% ( -18.33%) 2711.06 +- 0.04% ( -17.89%) 2715.10 +- 0.61% ( -17.77%)
Hmean 16 4725.03 +- 0.03% ( -23.04%) 4875.65 +- 0.02% ( -20.59%) 4953.05 +- 0.28% ( -19.33%)
Hmean 32 9231.65 +- 0.10% ( -17.36%) 8704.89 +- 0.27% ( -22.07%) 10562.02 +- 0.36% ( -5.45%)
Hmean 64 15364.27 +- 0.19% ( -20.49%) 17786.64 +- 0.15% ( -7.95%) 19665.40 +- 0.22% ( 1.77%)
Hmean 128 42100.58 +- 0.13% ( 38.56%) 34946.28 +- 0.13% ( 15.02%) 38635.79 +- 0.06% ( 27.16%)
Hmean 256 30660.23 +- 1.08% ( -1.55%) 32307.67 +- 0.54% ( 3.74%) 31153.27 +- 0.12% ( 0.03%)
Hmean 512 24604.32 +- 0.14% ( -20.27%) 40408.50 +- 1.10% ( 30.95%) 38800.29 +- 1.23% ( 25.74%)
Hmean 1024 35535.47 +- 0.28% ( -9.32%) 41070.38 +- 2.56% ( 4.81%) 31308.29 +- 2.52% ( -20.11%)
Benchmark : dbench (filesystem stressor)
Varying parameter : number of clients
Unit : seconds (lower is better)
NOTE-1: This dbench version measures the average latency of a set of filesystem
operations, as we found the traditional dbench metric (throughput) to be
misleading.
NOTE-2: Due to high variability, we partition the original dataset and apply
statistical bootrapping (a resampling method). Accuracy is reported in the
form of 95% confidence intervals.
5.9.0-ondemand (BASELINE) 5.9.0-perfgov 5.9.0-sugov-noinv
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
SubAmean 1 98.79 +- 0.92 ( ) 83.36 +- 0.82 ( 15.62%) 84.82 +- 0.92 ( 14.14%)
SubAmean 2 116.00 +- 0.89 ( ) 102.12 +- 0.77 ( 11.96%) 109.63 +- 0.89 ( 5.49%)
SubAmean 4 149.90 +- 1.03 ( ) 132.12 +- 0.91 ( 11.86%) 143.90 +- 1.15 ( 4.00%)
SubAmean 8 182.41 +- 1.13 ( ) 159.86 +- 0.93 ( 12.36%) 165.82 +- 1.03 ( 9.10%)
SubAmean 16 237.83 +- 1.23 ( ) 219.46 +- 1.14 ( 7.72%) 229.28 +- 1.19 ( 3.59%)
SubAmean 32 334.34 +- 1.49 ( ) 309.94 +- 1.42 ( 7.30%) 321.19 +- 1.36 ( 3.93%)
SubAmean 64 576.61 +- 2.16 ( ) 540.75 +- 2.00 ( 6.22%) 551.27 +- 1.99 ( 4.39%)
SubAmean 128 1350.07 +- 4.14 ( ) 1205.47 +- 3.20 ( 10.71%) 1280.26 +- 3.75 ( 5.17%)
SubAmean 256 3444.42 +- 7.97 ( ) 3698.00 +- 27.43 ( -7.36%) 3494.14 +- 7.81 ( -1.44%)
SubAmean 2048 39457.89 +- 29.01 ( ) 34105.33 +- 41.85 ( 13.57%) 39688.52 +- 36.26 ( -0.58%)
5.9.0-sugov-max 5.9.0-sugov-mid 5.9.0-sugov-P0
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
SubAmean 1 85.68 +- 1.04 ( 13.27%) 84.16 +- 0.84 ( 14.81%) 83.99 +- 0.90 ( 14.99%)
SubAmean 2 108.42 +- 0.95 ( 6.54%) 109.91 +- 1.39 ( 5.24%) 112.06 +- 0.91 ( 3.39%)
SubAmean 4 136.90 +- 1.04 ( 8.67%) 137.59 +- 0.93 ( 8.21%) 136.55 +- 0.95 ( 8.91%)
SubAmean 8 163.15 +- 0.96 ( 10.56%) 166.07 +- 1.02 ( 8.96%) 165.81 +- 0.99 ( 9.10%)
SubAmean 16 224.86 +- 1.12 ( 5.45%) 223.83 +- 1.06 ( 5.89%) 230.66 +- 1.19 ( 3.01%)
SubAmean 32 320.51 +- 1.38 ( 4.13%) 322.85 +- 1.49 ( 3.44%) 321.96 +- 1.46 ( 3.70%)
SubAmean 64 553.25 +- 1.93 ( 4.05%) 554.19 +- 2.08 ( 3.89%) 562.26 +- 2.22 ( 2.49%)
SubAmean 128 1264.35 +- 3.72 ( 6.35%) 1256.99 +- 3.46 ( 6.89%) 2018.97 +- 18.79 ( -49.55%)
SubAmean 256 3466.25 +- 8.25 ( -0.63%) 3450.58 +- 8.44 ( -0.18%) 5032.12 +- 38.74 ( -46.09%)
SubAmean 2048 39133.10 +- 45.71 ( 0.82%) 39905.95 +- 34.33 ( -1.14%) 53811.86 +-193.04 ( -36.38%)
Benchmark : kernbench (kernel compilation)
Varying parameter : number of jobs
Unit : seconds (lower is better)
5.9.0-ondemand (BASELINE) 5.9.0-perfgov 5.9.0-sugov-noinv
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 2 471.71 +- 26.61% ( ) 409.88 +- 16.99% ( 13.11%) 430.63 +- 0.18% ( 8.71%)
Amean 4 211.87 +- 0.58% ( ) 194.03 +- 0.74% ( 8.42%) 215.33 +- 0.64% ( -1.63%)
Amean 8 109.79 +- 1.27% ( ) 101.43 +- 1.53% ( 7.61%) 111.05 +- 1.95% ( -1.15%)
Amean 16 59.50 +- 1.28% ( ) 55.61 +- 1.35% ( 6.55%) 59.65 +- 1.78% ( -0.24%)
Amean 32 34.94 +- 1.22% ( ) 32.36 +- 1.95% ( 7.41%) 35.44 +- 0.63% ( -1.43%)
Amean 64 22.58 +- 0.38% ( ) 20.97 +- 1.28% ( 7.11%) 22.41 +- 1.73% ( 0.74%)
Amean 128 17.72 +- 0.44% ( ) 16.68 +- 0.32% ( 5.88%) 17.65 +- 0.96% ( 0.37%)
Amean 256 16.44 +- 0.53% ( ) 15.76 +- 0.32% ( 4.18%) 16.76 +- 0.60% ( -1.93%)
Amean 512 16.54 +- 0.21% ( ) 15.62 +- 0.41% ( 5.53%) 16.84 +- 0.85% ( -1.83%)
5.9.0-sugov-max 5.9.0-sugov-mid 5.9.0-sugov-P0
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 2 421.30 +- 0.24% ( 10.69%) 419.26 +- 0.15% ( 11.12%) 414.38 +- 0.33% ( 12.15%)
Amean 4 217.81 +- 5.53% ( -2.80%) 211.63 +- 0.99% ( 0.12%) 208.43 +- 0.47% ( 1.63%)
Amean 8 108.80 +- 0.43% ( 0.90%) 108.48 +- 1.44% ( 1.19%) 108.59 +- 3.08% ( 1.09%)
Amean 16 58.84 +- 0.74% ( 1.12%) 58.37 +- 0.94% ( 1.91%) 57.78 +- 0.78% ( 2.90%)
Amean 32 34.04 +- 2.00% ( 2.59%) 34.28 +- 1.18% ( 1.91%) 33.98 +- 2.21% ( 2.75%)
Amean 64 22.22 +- 1.69% ( 1.60%) 22.27 +- 1.60% ( 1.38%) 22.25 +- 1.41% ( 1.47%)
Amean 128 17.55 +- 0.24% ( 0.97%) 17.53 +- 0.94% ( 1.04%) 17.49 +- 0.43% ( 1.30%)
Amean 256 16.51 +- 0.46% ( -0.40%) 16.48 +- 0.48% ( -0.19%) 16.44 +- 1.21% ( 0.00%)
Amean 512 16.50 +- 0.35% ( 0.19%) 16.35 +- 0.42% ( 1.14%) 16.37 +- 0.33% ( 0.99%)
Benchmark : gitsource (time to run the git unit test suite)
Varying parameter : none
Unit : seconds (lower is better)
5.9.0-ondemand (BASELINE) 5.9.0-perfgov 5.9.0-sugov-noinv
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 1035.76 +- 0.30% ( ) 688.21 +- 0.04% ( 33.56%) 1003.85 +- 0.14% ( 3.08%)
5.9.0-sugov-max 5.9.0-sugov-mid 5.9.0-sugov-P0
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 995.82 +- 0.08% ( 3.86%) 1011.98 +- 0.03% ( 2.30%) 986.87 +- 0.19% ( 4.72%)
3. POWER CONSUMPTION TABLE
==========================
Average power consumption (watts).
--------------------------------------------------------------------------
ondemand perfgov sugov-noinv sugov-max sugov-mid sugov-P0
--------------------------------------------------------------------------
tbench4 227.25 281.83 244.17 236.76 241.50 247.99
dbench4 151.97 161.87 157.08 158.10 158.06 153.73
kernbench 162.78 167.22 162.90 164.19 164.65 164.72
gitsource 133.65 139.00 133.04 134.43 134.18 134.32
Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
---
arch/x86/kernel/smpboot.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index da410bd36af6..ed0d02d332cf 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -2054,6 +2054,8 @@ static bool amd_set_max_freq_ratio(void)
}
perf_ratio = div_u64(highest_perf * SCHED_CAPACITY_SCALE, nominal_perf);
+ /* midpoint between max_boost and max_P */
+ perf_ratio = (perf_ratio + SCHED_CAPACITY_SCALE) >> 1;
if (!perf_ratio) {
pr_debug("Non-zero highest/nominal perf values led to a 0 ratio\n");
return false;
--
2.26.2
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v3 3/3] x86: Print ratio freq_max/freq_base used in frequency invariance calculations
2020-11-10 20:05 [PATCH v3 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
2020-11-10 20:05 ` [PATCH v3 1/3] x86, sched: Calculate frequency invariance for AMD systems Giovanni Gherdovich
2020-11-10 20:05 ` [PATCH v3 2/3] x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC Giovanni Gherdovich
@ 2020-11-10 20:05 ` Giovanni Gherdovich
2020-11-12 18:33 ` [PATCH v3 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
3 siblings, 0 replies; 5+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 20:05 UTC (permalink / raw)
To: Borislav Petkov, Thomas Gleixner, Ingo Molnar, Peter Zijlstra,
Len Brown, Rafael J . Wysocki
Cc: Jon Grimm, Nathan Fontenot, Yazen Ghannam, Thomas Lendacky,
Mel Gorman, Pu Wen, Viresh Kumar, Juri Lelli, Vincent Guittot,
Dietmar Eggemann, Doug Smythies, x86, linux-pm, linux-kernel,
linux-acpi, Giovanni Gherdovich
The value freq_max/freq_base is a fundamental component of frequency
invariance calculations. It may come from a variety of sources such as MSRs
or ACPI data, tracking it down when troubleshooting a system could be
non-trivial. It is worth saving it in the kernel logs.
# dmesg | grep 'Estimated ratio of average max'
[ 14.024036] smpboot: Estimated ratio of average max frequency by base frequency (times 1024): 1289
Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
---
arch/x86/kernel/smpboot.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ed0d02d332cf..7affe6ef0259 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -2110,6 +2110,7 @@ static void init_freq_invariance(bool secondary, bool cppc_ready)
if (ret) {
init_counter_refs();
static_branch_enable(&arch_scale_freq_key);
+ pr_info("Estimated ratio of average max frequency by base frequency (times 1024): %llu\n", arch_max_freq_ratio);
} else {
pr_debug("Couldn't determine max cpu frequency, necessary for scale-invariant accounting.\n");
}
--
2.26.2
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* Re: [PATCH v3 0/3] Add support for frequency invariance to AMD EPYC Zen2
2020-11-10 20:05 [PATCH v3 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
` (2 preceding siblings ...)
2020-11-10 20:05 ` [PATCH v3 3/3] x86: Print ratio freq_max/freq_base used in frequency invariance calculations Giovanni Gherdovich
@ 2020-11-12 18:33 ` Giovanni Gherdovich
3 siblings, 0 replies; 5+ messages in thread
From: Giovanni Gherdovich @ 2020-11-12 18:33 UTC (permalink / raw)
To: Borislav Petkov, Thomas Gleixner, Ingo Molnar, Peter Zijlstra,
Len Brown, Rafael J . Wysocki
Cc: Jon Grimm, Nathan Fontenot, Yazen Ghannam, Thomas Lendacky,
Mel Gorman, Pu Wen, Viresh Kumar, Juri Lelli, Vincent Guittot,
Dietmar Eggemann, Doug Smythies, x86, linux-pm, linux-kernel,
linux-acpi
On Tue, 2020-11-10 at 21:05 +0100, Giovanni Gherdovich wrote:
> v2 at https://lore.kernel.org/lkml/20201110183054.15883-1-ggherdovich@suse.cz/
>
> Changes wrt v2:
>
> - "code golf" on the function function init_freq_invariance_cppc().
> Make better use of the "secondary" argument to init_freq_invariance(),
> which was introduced at b56e7d45e807 ("x86, sched: Don't enable static key
> when starting secondary CPUs") to deal with CPU hotplug.
The Intel 0-day bot reported a build error due to not guarding a part
of the patch with CONFIG_ACPI_CPPC_LIB. I've sent a v4 to fix that.
v4 at https://lore.kernel.org/lkml/20201112182614.10700-1-ggherdovich@suse.cz/
is now the most up-to-date version, ignore this one.
Thanks,
Giovanni
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