* [PATCH 0/3] Add support for frequency invariance to AMD EPYC Zen2
@ 2020-11-10 8:39 Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems Giovanni Gherdovich
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 8:39 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
This series adds support for frequency invariant accounting on AMD EPYC Zen2
(aka "Rome"). The first patch by Nathan lays out the foundation by querying
ACPI infrastructure for the max boost frequency of the system. Specifically,
this value is available via the CPPC machinery; the previous EPYC generation,
namely Zen aka "Naples", doesn't implement that and frequency invariance won't
be supported.
The second patch sets the estimate for freq_max to be the midpoint between
max_boost and max_P, as that works slightly better in practice.
A side effect of this series is to provide, with the invariant schedutil
governor, a suitable baseline to evaluate a (still work-in-progress)
CPPC-based cpufreq driver for the AMD platform (see
https://lore.kernel.org/lkml/cover.1562781484.git.Janakarajan.Natarajan@amd.com
if/when it will resubmitted.
Giovanni Gherdovich (2):
x86, sched: Use midpoint of max_boost and max_P for frequency
invariance on AMD EPYC
x86: Print ratio freq_max/freq_base used in frequency invariance
calculations
Nathan Fontenot (1):
x86, sched: Calculate frequency invariance for AMD systems
arch/x86/include/asm/topology.h | 8 ++++
arch/x86/kernel/smpboot.c | 79 +++++++++++++++++++++++++++++----
drivers/acpi/cppc_acpi.c | 5 +++
3 files changed, 84 insertions(+), 8 deletions(-)
--
2.26.2
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems
2020-11-10 8:39 [PATCH 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
@ 2020-11-10 8:39 ` Giovanni Gherdovich
2020-11-10 9:49 ` Peter Zijlstra
2020-11-10 8:39 ` [PATCH 2/3] x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 3/3] x86: Print ratio freq_max/freq_base used in frequency invariance calculations Giovanni Gherdovich
2 siblings, 1 reply; 6+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 8:39 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: cosmetic changes ]
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 | 5 +++
3 files changed, 81 insertions(+), 8 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..89016cc96948 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) {
@@ -2027,7 +2031,47 @@ static bool intel_set_max_freq_ratio(void)
return true;
}
-static void init_counter_refs(void)
+#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 *arg)
{
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;
@@ -2047,22 +2091,38 @@ static void init_freq_invariance(bool secondary)
if (secondary) {
if (static_branch_likely(&arch_scale_freq_key)) {
- init_counter_refs();
+ init_counter_refs(NULL);
}
return;
}
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();
+ init_counter_refs(NULL);
static_branch_enable(&arch_scale_freq_key);
} else {
pr_debug("Couldn't determine max cpu frequency, necessary for scale-invariant accounting.\n");
}
}
+#ifdef CONFIG_ACPI
+void init_freq_invariance_cppc(void)
+{
+ init_freq_invariance(false, true);
+
+ if (static_branch_likely(&arch_scale_freq_key))
+ on_each_cpu(init_counter_refs, NULL, 0);
+}
+#endif
+
static void disable_freq_invariance_workfn(struct work_struct *work)
{
static_branch_disable(&arch_scale_freq_key);
@@ -2112,7 +2172,7 @@ 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..e1969ff876ff 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 +851,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
goto out_free;
}
+ /* Only needed once, so call on CPU0 */
+ if (pr->id == 0)
+ init_freq_invariance_cppc();
+
kfree(output.pointer);
return 0;
--
2.26.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/3] x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC
2020-11-10 8:39 [PATCH 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems Giovanni Gherdovich
@ 2020-11-10 8:39 ` Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 3/3] x86: Print ratio freq_max/freq_base used in frequency invariance calculations Giovanni Gherdovich
2 siblings, 0 replies; 6+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 8:39 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 89016cc96948..1e6fed437b0c 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] 6+ messages in thread
* [PATCH 3/3] x86: Print ratio freq_max/freq_base used in frequency invariance calculations
2020-11-10 8:39 [PATCH 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 2/3] x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC Giovanni Gherdovich
@ 2020-11-10 8:39 ` Giovanni Gherdovich
2 siblings, 0 replies; 6+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 8:39 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 1e6fed437b0c..ad0647b2d7c3 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(NULL);
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
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems
2020-11-10 8:39 ` [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems Giovanni Gherdovich
@ 2020-11-10 9:49 ` Peter Zijlstra
2020-11-10 18:45 ` Giovanni Gherdovich
0 siblings, 1 reply; 6+ messages in thread
From: Peter Zijlstra @ 2020-11-10 9:49 UTC (permalink / raw)
To: Giovanni Gherdovich
Cc: Borislav Petkov, Thomas Gleixner, Ingo Molnar, Len Brown,
Rafael J . Wysocki, 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, Nov 10, 2020 at 09:39:34AM +0100, Giovanni Gherdovich wrote:
> +#ifdef CONFIG_ACPI
> +void init_freq_invariance_cppc(void)
> +{
> + init_freq_invariance(false, true);
> +
> + if (static_branch_likely(&arch_scale_freq_key))
> + on_each_cpu(init_counter_refs, NULL, 0);
> +}
> +#endif
> +
> static void disable_freq_invariance_workfn(struct work_struct *work)
> {
> static_branch_disable(&arch_scale_freq_key);
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index 7a99b19bb893..e1969ff876ff 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 +851,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
> goto out_free;
> }
>
> + /* Only needed once, so call on CPU0 */
> + if (pr->id == 0)
> + init_freq_invariance_cppc();
> +
This seems broken vs lovely things like booting with maxcpus= or
physical hotplug where you add logical CPUs.
Given the latter hunk limits it to one invocation (is phys_id 0
guaranteed to exist? Can a BIOS monkey screw us over?) only to then call
it on all CPUs, shouldn't this be changed to let
acpi_cppc_processor_probe() call it for every CPU that comes online?
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems
2020-11-10 9:49 ` Peter Zijlstra
@ 2020-11-10 18:45 ` Giovanni Gherdovich
0 siblings, 0 replies; 6+ messages in thread
From: Giovanni Gherdovich @ 2020-11-10 18:45 UTC (permalink / raw)
To: Peter Zijlstra
Cc: Borislav Petkov, Thomas Gleixner, Ingo Molnar, Len Brown,
Rafael J . Wysocki, 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 10:49 +0100, Peter Zijlstra wrote:
> On Tue, Nov 10, 2020 at 09:39:34AM +0100, Giovanni Gherdovich wrote:
>
> > +#ifdef CONFIG_ACPI
> > +void init_freq_invariance_cppc(void)
> > +{
> > + init_freq_invariance(false, true);
> > +
> > + if (static_branch_likely(&arch_scale_freq_key))
> > + on_each_cpu(init_counter_refs, NULL, 0);
> > +}
> > +#endif
> > +
> > static void disable_freq_invariance_workfn(struct work_struct *work)
> > {
> > static_branch_disable(&arch_scale_freq_key);
> > diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> > index 7a99b19bb893..e1969ff876ff 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 +851,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
> > goto out_free;
> > }
> >
> > + /* Only needed once, so call on CPU0 */
> > + if (pr->id == 0)
> > + init_freq_invariance_cppc();
> > +
>
> This seems broken vs lovely things like booting with maxcpus= or
> physical hotplug where you add logical CPUs.
Right.
>
> Given the latter hunk limits it to one invocation (is phys_id 0
> guaranteed to exist? Can a BIOS monkey screw us over?) only to then call
> it on all CPUs, shouldn't this be changed to let
> acpi_cppc_processor_probe() call it for every CPU that comes online?
I sent a V2 that basically does that, it just makes sure that
"init_freq_invariance(secondary=false)" is called only once (the first CPU
that gets there), and init_counter_refs() instead is called by all.
Which makes me think, I could make better use of the "secondary" argument
to init_freq_invariance() and trim a couple of lines from
init_freq_invariance_cppc().
Giovanni
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-11-10 18:45 UTC | newest]
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2020-11-10 8:39 [PATCH 0/3] Add support for frequency invariance to AMD EPYC Zen2 Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 1/3] x86, sched: Calculate frequency invariance for AMD systems Giovanni Gherdovich
2020-11-10 9:49 ` Peter Zijlstra
2020-11-10 18:45 ` Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 2/3] x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC Giovanni Gherdovich
2020-11-10 8:39 ` [PATCH 3/3] x86: Print ratio freq_max/freq_base used in frequency invariance calculations Giovanni Gherdovich
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