* [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag
@ 2024-04-28 9:11 Xiaojian Du
2024-04-28 9:11 ` [PATCH 2/2] cpufreq: amd-pstate: change cpu freq transition delay for some models Xiaojian Du
2024-04-28 9:54 ` [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag Borislav Petkov
0 siblings, 2 replies; 6+ messages in thread
From: Xiaojian Du @ 2024-04-28 9:11 UTC (permalink / raw)
To: linux-pm, gautham.shenoy, Borislav.Petkov, mario.limonciello, ray.huang
Cc: Perry.Yuan, Perry Yuan, Xiaojian Du
From: Perry Yuan <perry.yuan@amd.com>
Some AMD Zen 4 processors support a new feature FAST CPPC which
allows for a faster CPPC loop due to internal architectual
enhancements. The goal of this faster loop is higher performance
at the same power consumption.
Reference:
Page 99 of PPR for AMD Family 19h Model 61h rev.B1
https://www.amd.com/content/dam/amd/en/documents/processor-tech-docs/programmer-references/56713-B1_3_05.zip
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Xiaojian Du <Xiaojian.Du@amd.com>
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/kernel/cpu/scattered.c | 1 +
2 files changed, 2 insertions(+)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 3c7434329661..6c128d463a14 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -470,6 +470,7 @@
#define X86_FEATURE_BHI_CTRL (21*32+ 2) /* "" BHI_DIS_S HW control available */
#define X86_FEATURE_CLEAR_BHB_HW (21*32+ 3) /* "" BHI_DIS_S HW control enabled */
#define X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT (21*32+ 4) /* "" Clear branch history at vmexit using SW loop */
+#define X86_FEATURE_FAST_CPPC (21*32 + 5) /* "" AMD Fast CPPC */
/*
* BUG word(s)
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index af5aa2c754c2..9c273c231f56 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -51,6 +51,7 @@ static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_PERFMON_V2, CPUID_EAX, 0, 0x80000022, 0 },
{ X86_FEATURE_AMD_LBR_V2, CPUID_EAX, 1, 0x80000022, 0 },
{ X86_FEATURE_AMD_LBR_PMC_FREEZE, CPUID_EAX, 2, 0x80000022, 0 },
+ { X86_FEATURE_FAST_CPPC, CPUID_EDX, 15, 0x80000007, 0 },
{ 0, 0, 0, 0, 0 }
};
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/2] cpufreq: amd-pstate: change cpu freq transition delay for some models
2024-04-28 9:11 [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag Xiaojian Du
@ 2024-04-28 9:11 ` Xiaojian Du
2024-04-28 9:54 ` [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag Borislav Petkov
1 sibling, 0 replies; 6+ messages in thread
From: Xiaojian Du @ 2024-04-28 9:11 UTC (permalink / raw)
To: linux-pm, gautham.shenoy, Borislav.Petkov, mario.limonciello, ray.huang
Cc: Perry.Yuan, Xiaojian Du
Some of AMD ZEN4 APU/CPU have support for adjusting the CPU core
clock more quickly and presicely according to CPU work loading.
This is advertised by the Fast CPPC x86 feature.
This change will only be effective in the *passive mode* of
AMD pstate driver. From the test results of different
transition delay values, 600us is chosen to make a balance
between performance and power consumption.
Some test results on AMD Ryzen 7840HS(Phoenix) APU:
1. Tbench
(Energy less is better, Throughput more is better,
PPW--Performance per Watt more is better)
============= =================== ============== =============== ============== =============== ============== =============== ===============
Trans Delay Tbench governor:schedutil, 3-iterations average
============= =================== ============== =============== ============== =============== ============== =============== ===============
1000us Clients 1 2 4 8 12 16 32
Energy/Joules 2010 2804 8768 17171 16170 15132 15027
Throughput/(MB/s) 114 259 1041 3010 3135 4851 4605
PPW 0.0567 0.0923 0.1187 0.1752 0.1938 0.3205 0.3064
600us Clients 1 2 4 8 12 16 32
Energy/Joules 2115 (5.22%) 2388 (-14.84%) 10700(22.03%) 16716 (-2.65%) 15939 (-1.43%) 15053 (-0.52%) 15083 (0.37% )
Throughput/(MB/s) 122 (7.02%) 234 (-9.65% ) 1188 (14.12%) 3003 (-0.23%) 3143 (0.26% ) 4842 (-0.19%) 4603 (-0.04%)
PPW 0.0576(1.59%) 0.0979(6.07% ) 0.111(-6.49%) 0.1796(2.51% ) 0.1971(1.70% ) 0.3216(0.34% ) 0.3051(-0.42%)
============= =================== ============== ================ ============= =============== ============== =============== ===============
2.Dbench
(Energy less is better, Throughput more is better,
PPW--Performance per Watt more is better)
============= =================== ============== =============== ============== =============== ============== =============== ===============
Trans Delay Dbench governor:schedutil, 3-iterations average
============= =================== ============== =============== ============== =============== ============== =============== ===============
1000us Clients 1 2 4 8 12 16 32
Energy/Joules 4890 3779 3567 5157 5611 6500 8163
Throughput/(MB/s) 327 167 220 577 775 938 1397
PPW 0.0668 0.0441 0.0616 0.1118 0.1381 0.1443 0.1711
600us Clients 1 2 4 8 12 16 32
Energy/Joules 4915 (0.51%) 4912 (29.98%) 3506 (-1.71%) 4907 (-4.85% ) 5011 (-10.69%) 5672 (-12.74%) 8141 (-0.27%)
Throughput/(MB/s) 348 (6.42%) 284 (70.06%) 220 (0.00% ) 518 (-10.23%) 712 (-8.13% ) 854 (-8.96% ) 1475 (5.58% )
PPW 0.0708(5.99%) 0.0578(31.07%) 0.0627(1.79% ) 0.1055(-5.64% ) 0.142(2.82% ) 0.1505(4.30% ) 0.1811(5.84% )
============= =================== ============== =============== ============== =============== ============== =============== ===============
3.Hackbench(less time is better)
============= =========================== ==========================
hackbench governor:schedutil
============= =========================== ==========================
Trans Delay Process Mode Ave time(s) Thread Mode Ave time(s)
1000us 14.484 14.484
600us 14.418(-0.46%) 15.41(+6.39%)
============= =========================== ==========================
4.Perf_sched_bench(less time is better)
============= =================== ============== ============== ============== =============== =============== =============
Trans Delay perf_sched_bench governor:schedutil
============= =================== ============== ============== ============== =============== =============== =============
1000us Groups 1 2 4 8 12 24
AveTime(s) 1.64 2.851 5.878 11.636 16.093 26.395
600us Groups 1 2 4 8 12 24
AveTime(s) 1.69(3.05%) 2.845(-0.21%) 5.843(-0.60%) 11.576(-0.52%) 16.092(-0.01%) 26.32(-0.28%)
============= ================== ============== ============== ============== =============== =============== ==============
5.Sysbench(higher is better)
============= ================== ============== ================= ============== ================ =============== =================
Sysbench governor:schedutil
============= ================== ============== ================= ============== ================ =============== =================
1000us Thread 1 2 4 8 12 24
Ave events 6020.98 12273.39 24119.82 46171.57 47074.37 47831.72
600us Thread 1 2 4 8 12 24
Ave events 6154.82(2.22%) 12271.63(-0.01%) 24392.5(1.13%) 46117.64(-0.12%) 46852.19(-0.47%) 47678.92(-0.32%)
============= ================== ============== ================= ============== ================ =============== =================
In conclusion, a shorter transition delay
of cpu clock will make a quite positive effect to improve PPW on Dbench test,
in the meanwhile , keep stable performance on Tbench,
Hackbench, Perf_sched_bench and Sysbench.
Signed-off-by: Xiaojian Du <Xiaojian.Du@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
---
drivers/cpufreq/amd-pstate.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 2015c9fcc3c9..8c8594f67af6 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -50,6 +50,7 @@
#define AMD_PSTATE_TRANSITION_LATENCY 20000
#define AMD_PSTATE_TRANSITION_DELAY 1000
+#define AMD_PSTATE_FAST_CPPC_TRANSITION_DELAY 600
#define AMD_PSTATE_PREFCORE_THRESHOLD 166
/*
@@ -868,7 +869,11 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
}
policy->cpuinfo.transition_latency = AMD_PSTATE_TRANSITION_LATENCY;
- policy->transition_delay_us = AMD_PSTATE_TRANSITION_DELAY;
+
+ if (cpu_feature_enabled(X86_FEATURE_FAST_CPPC))
+ policy->transition_delay_us = AMD_PSTATE_FAST_CPPC_TRANSITION_DELAY;
+ else
+ policy->transition_delay_us = AMD_PSTATE_TRANSITION_DELAY;
policy->min = min_freq;
policy->max = max_freq;
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag
2024-04-28 9:11 [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag Xiaojian Du
2024-04-28 9:11 ` [PATCH 2/2] cpufreq: amd-pstate: change cpu freq transition delay for some models Xiaojian Du
@ 2024-04-28 9:54 ` Borislav Petkov
2024-04-28 10:59 ` Du, Xiaojian
1 sibling, 1 reply; 6+ messages in thread
From: Borislav Petkov @ 2024-04-28 9:54 UTC (permalink / raw)
To: Xiaojian Du
Cc: linux-pm, gautham.shenoy, mario.limonciello, ray.huang, Perry.Yuan, lkml
+ lkml
On Sun, Apr 28, 2024 at 05:11:32PM +0800, Xiaojian Du wrote:
> From: Perry Yuan <perry.yuan@amd.com>
>
> Some AMD Zen 4 processors support a new feature FAST CPPC which
> allows for a faster CPPC loop due to internal architectual
> enhancements. The goal of this faster loop is higher performance
> at the same power consumption.
>
> Reference:
> Page 99 of PPR for AMD Family 19h Model 61h rev.B1
> https://www.amd.com/content/dam/amd/en/documents/processor-tech-docs/programmer-references/56713-B1_3_05.zip
This should say "See the PPR for AMD Family 19h Model 61h rev.B1, docID
56713" so that people can actually find it.
The URLs are flaky and change regularly so can't use them.
> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
> Signed-off-by: Xiaojian Du <Xiaojian.Du@amd.com>
> ---
> arch/x86/include/asm/cpufeatures.h | 1 +
> arch/x86/kernel/cpu/scattered.c | 1 +
> 2 files changed, 2 insertions(+)
Always use ./scripts/get_maintainer.pl when sending a patch to know who
to Cc.
Also, have a look at those to get an idea how the process works:
https://kernel.org/doc/html/latest/process/development-process.html
https://kernel.org/doc/html/latest/process/submitting-patches.html
>
> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> index 3c7434329661..6c128d463a14 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -470,6 +470,7 @@
> #define X86_FEATURE_BHI_CTRL (21*32+ 2) /* "" BHI_DIS_S HW control available */
> #define X86_FEATURE_CLEAR_BHB_HW (21*32+ 3) /* "" BHI_DIS_S HW control enabled */
> #define X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT (21*32+ 4) /* "" Clear branch history at vmexit using SW loop */
> +#define X86_FEATURE_FAST_CPPC (21*32 + 5) /* "" AMD Fast CPPC */
>
> /*
> * BUG word(s)
> diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
> index af5aa2c754c2..9c273c231f56 100644
> --- a/arch/x86/kernel/cpu/scattered.c
> +++ b/arch/x86/kernel/cpu/scattered.c
> @@ -51,6 +51,7 @@ static const struct cpuid_bit cpuid_bits[] = {
> { X86_FEATURE_PERFMON_V2, CPUID_EAX, 0, 0x80000022, 0 },
> { X86_FEATURE_AMD_LBR_V2, CPUID_EAX, 1, 0x80000022, 0 },
> { X86_FEATURE_AMD_LBR_PMC_FREEZE, CPUID_EAX, 2, 0x80000022, 0 },
> + { X86_FEATURE_FAST_CPPC, CPUID_EDX, 15, 0x80000007, 0 },
> { 0, 0, 0, 0, 0 }
> };
>
With the above addressed:
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
^ permalink raw reply [flat|nested] 6+ messages in thread
* RE: [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag
2024-04-28 9:54 ` [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag Borislav Petkov
@ 2024-04-28 10:59 ` Du, Xiaojian
2024-04-28 11:05 ` Borislav Petkov
0 siblings, 1 reply; 6+ messages in thread
From: Du, Xiaojian @ 2024-04-28 10:59 UTC (permalink / raw)
To: Borislav Petkov
Cc: linux-pm, Shenoy, Gautham Ranjal, Limonciello, Mario, Huang, Ray,
Yuan, Perry, lkml
[AMD Official Use Only - General]
Thanks a lot for review, I will modify before submitting.
Xiaojian
-----Original Message-----
From: Borislav Petkov <bp@alien8.de>
Sent: Sunday, April 28, 2024 5:54 PM
To: Du, Xiaojian <Xiaojian.Du@amd.com>
Cc: linux-pm@vger.kernel.org; Shenoy, Gautham Ranjal <gautham.shenoy@amd.com>; Limonciello, Mario <Mario.Limonciello@amd.com>; Huang, Ray <Ray.Huang@amd.com>; Yuan, Perry <Perry.Yuan@amd.com>; lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag
+ lkml
On Sun, Apr 28, 2024 at 05:11:32PM +0800, Xiaojian Du wrote:
> From: Perry Yuan <perry.yuan@amd.com>
>
> Some AMD Zen 4 processors support a new feature FAST CPPC which allows
> for a faster CPPC loop due to internal architectual enhancements. The
> goal of this faster loop is higher performance at the same power
> consumption.
>
> Reference:
> Page 99 of PPR for AMD Family 19h Model 61h rev.B1
> https://www.amd.com/content/dam/amd/en/documents/processor-tech-docs/p
> rogrammer-references/56713-B1_3_05.zip
This should say "See the PPR for AMD Family 19h Model 61h rev.B1, docID 56713" so that people can actually find it.
The URLs are flaky and change regularly so can't use them.
> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
> Signed-off-by: Xiaojian Du <Xiaojian.Du@amd.com>
> ---
> arch/x86/include/asm/cpufeatures.h | 1 +
> arch/x86/kernel/cpu/scattered.c | 1 +
> 2 files changed, 2 insertions(+)
Always use ./scripts/get_maintainer.pl when sending a patch to know who to Cc.
Also, have a look at those to get an idea how the process works:
https://kernel.org/doc/html/latest/process/development-process.html
https://kernel.org/doc/html/latest/process/submitting-patches.html
>
> diff --git a/arch/x86/include/asm/cpufeatures.h
> b/arch/x86/include/asm/cpufeatures.h
> index 3c7434329661..6c128d463a14 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -470,6 +470,7 @@
> #define X86_FEATURE_BHI_CTRL (21*32+ 2) /* "" BHI_DIS_S HW control available */
> #define X86_FEATURE_CLEAR_BHB_HW (21*32+ 3) /* "" BHI_DIS_S HW control enabled */
> #define X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT (21*32+ 4) /* "" Clear
> branch history at vmexit using SW loop */
> +#define X86_FEATURE_FAST_CPPC (21*32 + 5) /* "" AMD Fast CPPC */
>
> /*
> * BUG word(s)
> diff --git a/arch/x86/kernel/cpu/scattered.c
> b/arch/x86/kernel/cpu/scattered.c index af5aa2c754c2..9c273c231f56
> 100644
> --- a/arch/x86/kernel/cpu/scattered.c
> +++ b/arch/x86/kernel/cpu/scattered.c
> @@ -51,6 +51,7 @@ static const struct cpuid_bit cpuid_bits[] = {
> { X86_FEATURE_PERFMON_V2, CPUID_EAX, 0, 0x80000022, 0 },
> { X86_FEATURE_AMD_LBR_V2, CPUID_EAX, 1, 0x80000022, 0 },
> { X86_FEATURE_AMD_LBR_PMC_FREEZE, CPUID_EAX, 2, 0x80000022, 0 },
> + { X86_FEATURE_FAST_CPPC, CPUID_EDX, 15, 0x80000007, 0 },
> { 0, 0, 0, 0, 0 }
> };
>
With the above addressed:
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag
2024-04-28 10:59 ` Du, Xiaojian
@ 2024-04-28 11:05 ` Borislav Petkov
0 siblings, 0 replies; 6+ messages in thread
From: Borislav Petkov @ 2024-04-28 11:05 UTC (permalink / raw)
To: Du, Xiaojian
Cc: linux-pm, Shenoy, Gautham Ranjal, Limonciello, Mario, Huang, Ray,
Yuan, Perry, lkml
On Sun, Apr 28, 2024 at 10:59:50AM +0000, Du, Xiaojian wrote:
> Thanks a lot for review, I will modify before submitting.
Thanks.
Also, please do not top-post on a public ML but put your reply
underneath, like I just did.
That's also explained in those docs I pointed you to.
Thx.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag
@ 2024-04-29 7:03 Xiaojian Du
0 siblings, 0 replies; 6+ messages in thread
From: Xiaojian Du @ 2024-04-29 7:03 UTC (permalink / raw)
To: linux-kernel, linux-pm
Cc: tglx, mingo, bp, dave.hansen, hpa, daniel.sneddon, jpoimboe,
pawan.kumar.gupta, sandipan.das, kai.huang, perry.yuan, x86,
ray.huang, rafael, Xiaojian Du
From: Perry Yuan <perry.yuan@amd.com>
Some AMD Zen 4 processors support a new feature FAST CPPC which
allows for a faster CPPC loop due to internal architectual
enhancements. The goal of this faster loop is higher performance
at the same power consumption.
Reference:
See the page 99 of PPR for AMD Family 19h Model 61h rev.B1, docID 56713
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Xiaojian Du <Xiaojian.Du@amd.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/kernel/cpu/scattered.c | 1 +
2 files changed, 2 insertions(+)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 3c7434329661..6c128d463a14 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -470,6 +470,7 @@
#define X86_FEATURE_BHI_CTRL (21*32+ 2) /* "" BHI_DIS_S HW control available */
#define X86_FEATURE_CLEAR_BHB_HW (21*32+ 3) /* "" BHI_DIS_S HW control enabled */
#define X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT (21*32+ 4) /* "" Clear branch history at vmexit using SW loop */
+#define X86_FEATURE_FAST_CPPC (21*32 + 5) /* "" AMD Fast CPPC */
/*
* BUG word(s)
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index af5aa2c754c2..9c273c231f56 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -51,6 +51,7 @@ static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_PERFMON_V2, CPUID_EAX, 0, 0x80000022, 0 },
{ X86_FEATURE_AMD_LBR_V2, CPUID_EAX, 1, 0x80000022, 0 },
{ X86_FEATURE_AMD_LBR_PMC_FREEZE, CPUID_EAX, 2, 0x80000022, 0 },
+ { X86_FEATURE_FAST_CPPC, CPUID_EDX, 15, 0x80000007, 0 },
{ 0, 0, 0, 0, 0 }
};
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2024-04-29 7:03 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-04-28 9:11 [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag Xiaojian Du
2024-04-28 9:11 ` [PATCH 2/2] cpufreq: amd-pstate: change cpu freq transition delay for some models Xiaojian Du
2024-04-28 9:54 ` [PATCH 1/2] x86/cpufeatures: Add AMD FAST CPPC feature flag Borislav Petkov
2024-04-28 10:59 ` Du, Xiaojian
2024-04-28 11:05 ` Borislav Petkov
2024-04-29 7:03 Xiaojian Du
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