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From: Peter Zijlstra <peterz@infradead.org>
To: Julia Lawall <julia.lawall@inria.fr>
Cc: Mel Gorman <mgorman@suse.de>, Ingo Molnar <mingo@redhat.com>,
	kernel-janitors@vger.kernel.org,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ben Segall <bsegall@google.com>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	linux-kernel@vger.kernel.org,
	Valentin Schneider <valentin.schneider@arm.com>,
	Gilles Muller <Gilles.Muller@inria.fr>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	viresh.kumar@linaro.org, srinivas.pandruvada@linux.intel.com
Subject: Re: [PATCH] sched/fair: check for idle core
Date: Wed, 21 Oct 2020 15:10:26 +0200	[thread overview]
Message-ID: <20201021131026.GY2651@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20201021121950.GF2628@hirez.programming.kicks-ass.net>

On Wed, Oct 21, 2020 at 02:19:50PM +0200, Peter Zijlstra wrote:
> On Wed, Oct 21, 2020 at 01:56:55PM +0200, Julia Lawall wrote:
> > Prior to 5.8, my machine was using intel_pstate and had few background
> > tasks.  Thus the problem wasn't visible in practice.  Starting with 5.8
> > the kernel decided that intel_cpufreq would be more appropriate, which
> > introduced kworkers every 0.004 seconds on all cores.
> 
> That still doesn't make any sense. Are you running the legacy on-demand
> thing or something?
> 
> Rafael, Srinivas, Viresh, how come it defaults to that?

Does we want something like this?

---
 arch/x86/configs/i386_defconfig   | 3 +--
 arch/x86/configs/x86_64_defconfig | 3 +--
 drivers/cpufreq/Kconfig           | 7 +++++--
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig
index 78210793d357..c343ad459737 100644
--- a/arch/x86/configs/i386_defconfig
+++ b/arch/x86/configs/i386_defconfig
@@ -41,8 +41,7 @@ CONFIG_PM_DEBUG=y
 CONFIG_PM_TRACE_RTC=y
 CONFIG_ACPI_DOCK=y
 CONFIG_ACPI_BGRT=y
-CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
-CONFIG_CPU_FREQ_GOV_ONDEMAND=y
+CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y
 CONFIG_X86_ACPI_CPUFREQ=y
 CONFIG_EFI_VARS=y
 CONFIG_KPROBES=y
diff --git a/arch/x86/configs/x86_64_defconfig b/arch/x86/configs/x86_64_defconfig
index 9936528e1939..23e1ea85c1ec 100644
--- a/arch/x86/configs/x86_64_defconfig
+++ b/arch/x86/configs/x86_64_defconfig
@@ -38,8 +38,7 @@ CONFIG_PM_DEBUG=y
 CONFIG_PM_TRACE_RTC=y
 CONFIG_ACPI_DOCK=y
 CONFIG_ACPI_BGRT=y
-CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
-CONFIG_CPU_FREQ_GOV_ONDEMAND=y
+CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y
 CONFIG_X86_ACPI_CPUFREQ=y
 CONFIG_IA32_EMULATION=y
 CONFIG_EFI_VARS=y
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 2c7171e0b001..8dfca6e9b836 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -37,8 +37,7 @@ config CPU_FREQ_STAT
 choice
 	prompt "Default CPUFreq governor"
 	default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
-	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if ARM64 || ARM
-	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if X86_INTEL_PSTATE && SMP
+	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if SMP
 	default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
 	help
 	  This option sets which CPUFreq governor shall be loaded at
@@ -71,6 +70,7 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE
 
 config CPU_FREQ_DEFAULT_GOV_ONDEMAND
 	bool "ondemand"
+	depends on !SMP
 	select CPU_FREQ_GOV_ONDEMAND
 	select CPU_FREQ_GOV_PERFORMANCE
 	help
@@ -83,6 +83,7 @@ config CPU_FREQ_DEFAULT_GOV_ONDEMAND
 
 config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
 	bool "conservative"
+	depends on !SMP
 	select CPU_FREQ_GOV_CONSERVATIVE
 	select CPU_FREQ_GOV_PERFORMANCE
 	help
@@ -144,6 +145,7 @@ config CPU_FREQ_GOV_USERSPACE
 
 config CPU_FREQ_GOV_ONDEMAND
 	tristate "'ondemand' cpufreq policy governor"
+	depends on !SMP
 	select CPU_FREQ_GOV_COMMON
 	help
 	  'ondemand' - This driver adds a dynamic cpufreq policy governor.
@@ -163,6 +165,7 @@ config CPU_FREQ_GOV_ONDEMAND
 config CPU_FREQ_GOV_CONSERVATIVE
 	tristate "'conservative' cpufreq governor"
 	depends on CPU_FREQ
+	depends on !SMP
 	select CPU_FREQ_GOV_COMMON
 	help
 	  'conservative' - this driver is rather similar to the 'ondemand'

WARNING: multiple messages have this Message-ID (diff)
From: Peter Zijlstra <peterz@infradead.org>
To: Julia Lawall <julia.lawall@inria.fr>
Cc: Mel Gorman <mgorman@suse.de>, Ingo Molnar <mingo@redhat.com>,
	kernel-janitors@vger.kernel.org,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ben Segall <bsegall@google.com>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	linux-kernel@vger.kernel.org,
	Valentin Schneider <valentin.schneider@arm.com>,
	Gilles Muller <Gilles.Muller@inria.fr>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	viresh.kumar@linaro.org, srinivas.pandruvada@linux.intel.com
Subject: Re: [PATCH] sched/fair: check for idle core
Date: Wed, 21 Oct 2020 13:10:26 +0000	[thread overview]
Message-ID: <20201021131026.GY2651@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20201021121950.GF2628@hirez.programming.kicks-ass.net>

On Wed, Oct 21, 2020 at 02:19:50PM +0200, Peter Zijlstra wrote:
> On Wed, Oct 21, 2020 at 01:56:55PM +0200, Julia Lawall wrote:
> > Prior to 5.8, my machine was using intel_pstate and had few background
> > tasks.  Thus the problem wasn't visible in practice.  Starting with 5.8
> > the kernel decided that intel_cpufreq would be more appropriate, which
> > introduced kworkers every 0.004 seconds on all cores.
> 
> That still doesn't make any sense. Are you running the legacy on-demand
> thing or something?
> 
> Rafael, Srinivas, Viresh, how come it defaults to that?

Does we want something like this?

---
 arch/x86/configs/i386_defconfig   | 3 +--
 arch/x86/configs/x86_64_defconfig | 3 +--
 drivers/cpufreq/Kconfig           | 7 +++++--
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig
index 78210793d357..c343ad459737 100644
--- a/arch/x86/configs/i386_defconfig
+++ b/arch/x86/configs/i386_defconfig
@@ -41,8 +41,7 @@ CONFIG_PM_DEBUG=y
 CONFIG_PM_TRACE_RTC=y
 CONFIG_ACPI_DOCK=y
 CONFIG_ACPI_BGRT=y
-CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
-CONFIG_CPU_FREQ_GOV_ONDEMAND=y
+CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y
 CONFIG_X86_ACPI_CPUFREQ=y
 CONFIG_EFI_VARS=y
 CONFIG_KPROBES=y
diff --git a/arch/x86/configs/x86_64_defconfig b/arch/x86/configs/x86_64_defconfig
index 9936528e1939..23e1ea85c1ec 100644
--- a/arch/x86/configs/x86_64_defconfig
+++ b/arch/x86/configs/x86_64_defconfig
@@ -38,8 +38,7 @@ CONFIG_PM_DEBUG=y
 CONFIG_PM_TRACE_RTC=y
 CONFIG_ACPI_DOCK=y
 CONFIG_ACPI_BGRT=y
-CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
-CONFIG_CPU_FREQ_GOV_ONDEMAND=y
+CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y
 CONFIG_X86_ACPI_CPUFREQ=y
 CONFIG_IA32_EMULATION=y
 CONFIG_EFI_VARS=y
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 2c7171e0b001..8dfca6e9b836 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -37,8 +37,7 @@ config CPU_FREQ_STAT
 choice
 	prompt "Default CPUFreq governor"
 	default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
-	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if ARM64 || ARM
-	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if X86_INTEL_PSTATE && SMP
+	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if SMP
 	default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
 	help
 	  This option sets which CPUFreq governor shall be loaded at
@@ -71,6 +70,7 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE
 
 config CPU_FREQ_DEFAULT_GOV_ONDEMAND
 	bool "ondemand"
+	depends on !SMP
 	select CPU_FREQ_GOV_ONDEMAND
 	select CPU_FREQ_GOV_PERFORMANCE
 	help
@@ -83,6 +83,7 @@ config CPU_FREQ_DEFAULT_GOV_ONDEMAND
 
 config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
 	bool "conservative"
+	depends on !SMP
 	select CPU_FREQ_GOV_CONSERVATIVE
 	select CPU_FREQ_GOV_PERFORMANCE
 	help
@@ -144,6 +145,7 @@ config CPU_FREQ_GOV_USERSPACE
 
 config CPU_FREQ_GOV_ONDEMAND
 	tristate "'ondemand' cpufreq policy governor"
+	depends on !SMP
 	select CPU_FREQ_GOV_COMMON
 	help
 	  'ondemand' - This driver adds a dynamic cpufreq policy governor.
@@ -163,6 +165,7 @@ config CPU_FREQ_GOV_ONDEMAND
 config CPU_FREQ_GOV_CONSERVATIVE
 	tristate "'conservative' cpufreq governor"
 	depends on CPU_FREQ
+	depends on !SMP
 	select CPU_FREQ_GOV_COMMON
 	help
 	  'conservative' - this driver is rather similar to the 'ondemand'

  parent reply	other threads:[~2020-10-21 13:10 UTC|newest]

Thread overview: 134+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-20 16:37 [PATCH] sched/fair: check for idle core Julia Lawall
2020-10-20 16:37 ` Julia Lawall
2020-10-21  7:29 ` Vincent Guittot
2020-10-21  7:29   ` Vincent Guittot
2020-10-21 11:13   ` Peter Zijlstra
2020-10-21 11:13     ` Peter Zijlstra
2020-10-21 12:27   ` Vincent Guittot
2020-10-21 12:27     ` Vincent Guittot
2020-10-21 11:20 ` Mel Gorman
2020-10-21 11:20   ` Mel Gorman
2020-10-21 11:56   ` Julia Lawall
2020-10-21 11:56     ` Julia Lawall
2020-10-21 12:19     ` Peter Zijlstra
2020-10-21 12:19       ` Peter Zijlstra
2020-10-21 12:42       ` Julia Lawall
2020-10-21 12:42         ` Julia Lawall
2020-10-21 12:52         ` Peter Zijlstra
2020-10-21 12:52           ` Peter Zijlstra
2020-10-21 13:43           ` Julia Lawall
2020-10-21 18:18           ` Rafael J. Wysocki
2020-10-21 18:18             ` Rafael J. Wysocki
2020-10-21 18:15         ` Rafael J. Wysocki
2020-10-21 18:15           ` Rafael J. Wysocki
2020-10-21 19:47           ` Julia Lawall
2020-10-21 19:47             ` Julia Lawall
2020-10-21 20:25             ` Rafael J. Wysocki
2020-10-21 20:25               ` Rafael J. Wysocki
2020-10-21 13:10       ` Peter Zijlstra [this message]
2020-10-21 13:10         ` Peter Zijlstra
2020-10-21 18:11         ` Rafael J. Wysocki
2020-10-21 18:11           ` Rafael J. Wysocki
2020-10-22  4:41           ` Viresh Kumar
2020-10-22  4:53             ` Viresh Kumar
2020-10-22  7:11           ` Peter Zijlstra
2020-10-22  7:11             ` Peter Zijlstra
2020-10-22 10:47             ` Viresh Kumar
2020-10-22 10:59               ` Viresh Kumar
2020-10-22 11:45               ` Rafael J. Wysocki
2020-10-22 11:45                 ` Rafael J. Wysocki
2020-10-22 12:02                 ` default cpufreq gov, was: " Peter Zijlstra
2020-10-22 12:02                   ` Peter Zijlstra
2020-10-22 12:19                   ` Rafael J. Wysocki
2020-10-22 12:19                     ` Rafael J. Wysocki
2020-10-22 12:29                     ` Peter Zijlstra
2020-10-22 12:29                       ` Peter Zijlstra
2020-10-22 14:52                       ` Mel Gorman
2020-10-22 14:52                         ` Mel Gorman
2020-10-22 14:58                         ` Colin Ian King
2020-10-22 14:58                           ` Colin Ian King
2020-10-22 15:12                           ` Phil Auld
2020-10-22 15:12                             ` Phil Auld
2020-10-22 16:35                             ` Mel Gorman
2020-10-22 16:35                               ` Mel Gorman
2020-10-22 17:59                               ` Rafael J. Wysocki
2020-10-22 17:59                                 ` Rafael J. Wysocki
2020-10-22 20:32                                 ` Mel Gorman
2020-10-22 20:32                                   ` Mel Gorman
2020-10-22 20:39                                   ` Phil Auld
2020-10-22 20:39                                     ` Phil Auld
2020-10-22 15:25                         ` Peter Zijlstra
2020-10-22 15:25                           ` Peter Zijlstra
2020-10-22 15:55                           ` Rafael J. Wysocki
2020-10-22 15:55                             ` Rafael J. Wysocki
2020-10-22 16:29                           ` Mel Gorman
2020-10-22 16:29                             ` Mel Gorman
2020-10-22 20:10                           ` Giovanni Gherdovich
2020-10-22 20:10                             ` Giovanni Gherdovich
2020-10-22 20:16                             ` Giovanni Gherdovich
2020-10-22 20:16                               ` Giovanni Gherdovich
2020-10-23  7:03                             ` Peter Zijlstra
2020-10-23  7:03                               ` Peter Zijlstra
2020-10-23 17:46                               ` Tom Lendacky
2020-10-23 17:46                                 ` Tom Lendacky
2020-10-26 19:52                                 ` Fontenot, Nathan
2020-10-26 19:52                                   ` Fontenot, Nathan
2020-10-22 15:45                       ` A L
2020-10-22 15:45                         ` A L
2020-10-22 15:55                         ` Vincent Guittot
2020-10-22 15:55                           ` Vincent Guittot
2020-10-23  5:11                           ` Viresh Kumar
2020-10-23  5:23                             ` Viresh Kumar
2020-10-22 16:23                   ` [PATCH] cpufreq: Avoid configuring old governors as default with intel_pstate Rafael J. Wysocki
2020-10-22 16:23                     ` Rafael J. Wysocki
2020-10-23  6:17                     ` Viresh Kumar
2020-10-23  6:29                       ` Viresh Kumar
2020-10-23 11:59                       ` Rafael J. Wysocki
2020-10-23 11:59                         ` Rafael J. Wysocki
2020-10-23 15:15                     ` [PATCH v2] " Rafael J. Wysocki
2020-10-23 15:15                       ` Rafael J. Wysocki
2020-10-27  3:01                       ` Viresh Kumar
2020-10-27  3:13                         ` Viresh Kumar
2020-10-27 11:11                   ` default cpufreq gov, was: [PATCH] sched/fair: check for idle core Qais Yousef
2020-10-27 11:26                     ` Valentin Schneider
2020-10-27 11:42                       ` Qais Yousef
2020-10-27 11:48                         ` Viresh Kumar
2020-10-27 11:48                           ` Viresh Kumar
2020-10-23  6:12                 ` Viresh Kumar
2020-10-23  6:24                   ` Viresh Kumar
2020-10-23 15:06                   ` Rafael J. Wysocki
2020-10-23 15:06                     ` Rafael J. Wysocki
2020-10-27  3:01                     ` Viresh Kumar
2020-10-27  3:13                       ` Viresh Kumar
2020-10-22 11:21             ` AW: " Walter Harms
2020-10-22 11:21               ` Walter Harms
2020-10-21 12:28     ` Mel Gorman
2020-10-21 12:28       ` Mel Gorman
2020-10-21 12:25   ` Vincent Guittot
2020-10-21 12:25     ` Vincent Guittot
2020-10-21 12:47     ` Mel Gorman
2020-10-21 12:47       ` Mel Gorman
2020-10-21 12:56       ` Julia Lawall
2020-10-21 12:56         ` Julia Lawall
2020-10-21 13:18         ` Mel Gorman
2020-10-21 13:18           ` Mel Gorman
2020-10-21 13:24           ` Julia Lawall
2020-10-21 13:24             ` Julia Lawall
2020-10-21 15:08             ` Mel Gorman
2020-10-21 15:08               ` Mel Gorman
2020-10-21 15:18               ` Julia Lawall
2020-10-21 15:18                 ` Julia Lawall
2020-10-21 15:23                 ` Vincent Guittot
2020-10-21 15:23                   ` Vincent Guittot
2020-10-21 15:33                   ` Julia Lawall
2020-10-21 15:33                     ` Julia Lawall
2020-10-21 15:19               ` Vincent Guittot
2020-10-21 15:19                 ` Vincent Guittot
2020-10-21 17:00                 ` Mel Gorman
2020-10-21 17:00                   ` Mel Gorman
2020-10-21 17:39                   ` Julia Lawall
2020-10-21 17:39                     ` Julia Lawall
2020-10-21 13:48           ` Julia Lawall
2020-10-21 13:48             ` Julia Lawall
2020-10-21 15:26             ` Mel Gorman
2020-10-21 15:26               ` Mel Gorman

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