Allow ondemand and conservative cpufreq governors to be used as default

PATCH In review Thomas Renninger 2 participants 3 messages Jun 28, 2007 – Jul 13, 2007

Subsystems (8)

Arm (32-bit) Arm sub-architectures PowerPC Arm i.MX and Layerscape +4 more subsystems

lore

Share & tools

lore

Thomas Renninger

author

2007-06-28 13:43 UTC #0 lore raw

PATCH 1/1 Allow ondemand and conservative cpufreq governors to be used as default

Hi Venkatesh,

do you give me your ack/signed off for this one?

Runtime tested to load ondemand and to fallback to performance governor (by faking the transition latency of the driver) on x86_64.

Thanks,

Thomas

Allow ondemand and conservative cpufreq governors to be used as default

Depending on the transition latency of the HW on cpufreq switches, the ondemand or conservative governor cannot be used with certain cpufreq drivers. Still the ondemand should be the default governor on a wide range of systems. This patch allows this and lets the governor fallback to the performance governor at cpufreq driver load time, if the driver does not support fast enough frequency switching.

Main benefit is that on e.g. installation or other systems without userspace support a working dynamic cpufreq support can be achieved on most systems by simply loading the cpufreq driver. This is especially essential for recent x86(_64) laptop hardware which may rely on working dynamic cpufreq OS support.

Signed-off-by Thomas Renninger <[email protected]>

---
 arch/arm/mach-imx/cpufreq.c                       |    1 
 arch/arm/mach-sa1100/cpu-sa1110.c                 |    1 
 arch/arm/plat-omap/cpu-omap.c                     |    1 
 arch/blackfin/mach-bf533/cpu.c                    |    2 -
 arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c       |    1 
 arch/i386/kernel/cpu/cpufreq/cpufreq-nforce2.c    |    1 
 arch/i386/kernel/cpu/cpufreq/e_powersaver.c       |    1 
 arch/i386/kernel/cpu/cpufreq/elanfreq.c           |    1 
 arch/i386/kernel/cpu/cpufreq/gx-suspmod.c         |    1 
 arch/i386/kernel/cpu/cpufreq/longhaul.c           |    1 
 arch/i386/kernel/cpu/cpufreq/p4-clockmod.c        |    1 
 arch/i386/kernel/cpu/cpufreq/powernow-k6.c        |    1 
 arch/i386/kernel/cpu/cpufreq/powernow-k7.c        |    2 -
 arch/i386/kernel/cpu/cpufreq/powernow-k8.c        |    1 
 arch/i386/kernel/cpu/cpufreq/sc520_freq.c         |    1 
 arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c |    1 
 arch/i386/kernel/cpu/cpufreq/speedstep-ich.c      |    1 
 arch/i386/kernel/cpu/cpufreq/speedstep-smi.c      |    1 
 arch/ia64/kernel/cpufreq/acpi-cpufreq.c           |    2 -
 arch/powerpc/platforms/cell/cbe_cpufreq.c         |    1 
 arch/powerpc/platforms/pasemi/cpufreq.c           |    2 -
 arch/powerpc/platforms/powermac/cpufreq_32.c      |    1 
 arch/powerpc/platforms/powermac/cpufreq_64.c      |    1 
 arch/sh/kernel/cpufreq.c                          |    1 
 arch/sparc64/kernel/us2e_cpufreq.c                |    1 
 drivers/cpufreq/Kconfig                           |   23 ++++++++++++++++++----
 drivers/cpufreq/cpufreq.c                         |   13 ++++++++++++
 drivers/cpufreq/cpufreq_conservative.c            |   12 ++++-------
 drivers/cpufreq/cpufreq_ondemand.c                |   22 ++++++++-------------
 include/linux/cpufreq.h                           |   16 ++++++++++++++-
 30 files changed, 61 insertions(+), 54 deletions(-)

arch/i386/kernel/cpu/cpufreq/powernow-k8.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
===================================================================
@@ -1205,7 +1205,6 @@ static int __cpuinit powernowk8_cpu_init
 	/* run on any CPU again */
 	set_cpus_allowed(current, oldmask);
 
-	pol->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	if (cpu_family == CPU_HW_PSTATE)
 		pol->cpus = cpumask_of_cpu(pol->cpu);
 	else

drivers/cpufreq/cpufreq_ondemand.c +9 ~~-13~~

Index: linux-2.6.22-rc6/drivers/cpufreq/cpufreq_ondemand.c
===================================================================
@@ -47,7 +47,7 @@ static unsigned int def_sampling_rate;
 			(def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
 #define MAX_SAMPLING_RATE			(500 * def_sampling_rate)
 #define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER	(1000)
-#define TRANSITION_LATENCY_LIMIT		(10 * 1000)
+#define TRANSITION_LATENCY_LIMIT		(10 * 1000 * 1000)
 
 static void do_dbs_timer(struct work_struct *work);

@@ -496,12 +496,6 @@ static int cpufreq_governor_dbs(struct c
 		if ((!cpu_online(cpu)) || (!policy->cur))
 			return -EINVAL;
 
-		if (policy->cpuinfo.transition_latency >
-				(TRANSITION_LATENCY_LIMIT * 1000)) {
-			printk(KERN_WARNING "ondemand governor failed to load "
-			       "due to too long transition latency\n");
-			return -EINVAL;
-		}
 		if (this_dbs_info->enable) /* Already enabled */
 			break;

@@ -573,11 +567,13 @@ static int cpufreq_governor_dbs(struct c
 	return 0;
 }
 
-static struct cpufreq_governor cpufreq_gov_dbs = {
-	.name = "ondemand",
-	.governor = cpufreq_governor_dbs,
-	.owner = THIS_MODULE,
+struct cpufreq_governor cpufreq_gov_ondemand = {
+	.name			= "ondemand",
+	.governor		= cpufreq_governor_dbs,
+	.max_transition_latency = TRANSITION_LATENCY_LIMIT,
+	.owner			= THIS_MODULE,
 };
+EXPORT_SYMBOL(cpufreq_gov_ondemand);
 
 static int __init cpufreq_gov_dbs_init(void)
 {

@@ -586,12 +582,12 @@ static int __init cpufreq_gov_dbs_init(v
 		printk(KERN_ERR "Creation of kondemand failed\n");
 		return -EFAULT;
 	}
-	return cpufreq_register_governor(&cpufreq_gov_dbs);
+	return cpufreq_register_governor(&cpufreq_gov_ondemand);
 }
 
 static void __exit cpufreq_gov_dbs_exit(void)
 {
-	cpufreq_unregister_governor(&cpufreq_gov_dbs);
+	cpufreq_unregister_governor(&cpufreq_gov_ondemand);
 	destroy_workqueue(kondemand_wq);
 }

include/linux/cpufreq.h +15 -1

Index: linux-2.6.22-rc6/include/linux/cpufreq.h
===================================================================
@@ -163,6 +163,9 @@ struct cpufreq_governor {
 	char	name[CPUFREQ_NAME_LEN];
 	int 	(*governor)	(struct cpufreq_policy *policy,
 				 unsigned int event);
+	unsigned int max_transition_latency; /* HW must be able to switch to
+			next freq faster than this value in nano secs or we
+			will fallback to performance governor */
 	struct list_head	governor_list;
 	struct module		*owner;
 };

@@ -292,12 +295,23 @@ static inline unsigned int cpufreq_get(u
  *********************************************************************/
 
 
-#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
+/*
+  Performance governor is fallback governor if any other gov failed to
+  auto load due latency restrictions
+*/
 extern struct cpufreq_governor cpufreq_gov_performance;
+#define CPUFREQ_PERFORMANCE_GOVERNOR	&cpufreq_gov_performance;
+#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
 #define CPUFREQ_DEFAULT_GOVERNOR	&cpufreq_gov_performance
 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
 extern struct cpufreq_governor cpufreq_gov_userspace;
 #define CPUFREQ_DEFAULT_GOVERNOR	&cpufreq_gov_userspace
+#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
+extern struct cpufreq_governor cpufreq_gov_ondemand;
+#define CPUFREQ_DEFAULT_GOVERNOR	&cpufreq_gov_ondemand;
+#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
+extern struct cpufreq_governor cpufreq_gov_conservative;
+#define CPUFREQ_DEFAULT_GOVERNOR	&cpufreq_gov_conservative;
 #endif

drivers/cpufreq/Kconfig +19 -4

Index: linux-2.6.22-rc6/drivers/cpufreq/Kconfig
===================================================================
@@ -56,10 +56,6 @@ config CPU_FREQ_STAT_DETAILS
 
 	  If in doubt, say N.
 
-# Note that it is not currently possible to set the other governors (such as ondemand)
-# as the default, since if they fail to initialise, cpufreq will be
-# left in an undefined state.
-
 choice
 	prompt "Default CPUFreq governor"
 	default CPU_FREQ_DEFAULT_GOV_USERSPACE if CPU_FREQ_SA1100 || CPU_FREQ_SA1110

@@ -85,6 +81,25 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE
 	  program shall be able to set the CPU dynamically without having
 	  to enable the userspace governor manually.
 
+config CPU_FREQ_DEFAULT_GOV_ONDEMAND
+	bool "ondemand"
+	select CPU_FREQ_GOV_ONDEMAND
+	select CPU_FREQ_GOV_PERFORMANCE
+	help
+	  Use the CPUFreq governor 'ondemand' as default. This allows
+	  you to get a full dynamic frequncy capable system by simply
+	  loading your cpufreq driver.
+	  Be aware that not all cpufreq drivers support the ondemand
+	  governor. If unsure have a look at the help section of the
+	  driver. Fallback governor will then be the performance
+	  governor.
+
+config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
+	bool "conservative"
+	select CPU_FREQ_GOV_CONSERVATIVE
+	select CPU_FREQ_GOV_PERFORMANCE
+	help
+	  See ondemand as default governor help above.
 endchoice
 
 config CPU_FREQ_GOV_PERFORMANCE

arch/i386/kernel/cpu/cpufreq/speedstep-smi.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c
===================================================================
@@ -290,7 +290,6 @@ static int speedstep_cpu_init(struct cpu
 		(speed / 1000));
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = speed;

drivers/cpufreq/cpufreq.c +13 -0

Index: linux-2.6.22-rc6/drivers/cpufreq/cpufreq.c
===================================================================
@@ -759,6 +759,8 @@ static int cpufreq_add_dev (struct sys_d
 	init_completion(&policy->kobj_unregister);
 	INIT_WORK(&policy->update, handle_update);
 
+	/* Set governor before ->init, so that driver could check it */
+	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	/* call driver. From then on the cpufreq must be able
 	 * to accept all calls to ->verify and ->setpolicy for this CPU
 	 */

@@ -1454,6 +1456,17 @@ static int __cpufreq_governor(struct cpu
 {
 	int ret;
 
+	if (policy->governor->max_transition_latency &&
+	    policy->cpuinfo.transition_latency >
+	    policy->governor->max_transition_latency) {
+		printk(KERN_WARNING "%s governor failed, too long"
+		       " transition latency of HW, fallback"
+		       " to %s governor\n",
+		       policy->governor->name,
+		       CPUFREQ_PERFORMANCE_GOVERNOR->name);
+		policy->governor = CPUFREQ_PERFORMANCE_GOVERNOR;
+	}
+
 	if (!try_module_get(policy->governor->owner))
 		return -EINVAL;

arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
===================================================================
@@ -663,7 +663,6 @@ static int acpi_cpufreq_cpu_init(struct 
 			policy->cpuinfo.transition_latency =
 			    perf->states[i].transition_latency * 1000;
 	}
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 
 	data->max_freq = perf->states[0].core_frequency * 1000;
 	/* table init */

arch/i386/kernel/cpu/cpufreq/cpufreq-nforce2.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/cpufreq-nforce2.c
===================================================================
@@ -363,7 +363,6 @@ static int nforce2_cpu_init(struct cpufr
 	policy->cur = nforce2_get(policy->cpu);
 	policy->min = policy->cpuinfo.min_freq;
 	policy->max = policy->cpuinfo.max_freq;
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 
 	return 0;
 }

arch/i386/kernel/cpu/cpufreq/e_powersaver.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/e_powersaver.c
===================================================================
@@ -253,7 +253,6 @@ static int eps_cpu_init(struct cpufreq_p
 		f_table[k].frequency = CPUFREQ_TABLE_END;
 	}
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 140000; /* 844mV -> 700mV in ns */
 	policy->cur = fsb * current_multiplier;

arch/i386/kernel/cpu/cpufreq/elanfreq.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/elanfreq.c
===================================================================
@@ -219,7 +219,6 @@ static int elanfreq_cpu_init(struct cpuf
 	}
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = elanfreq_get_cpu_frequency(0);

arch/i386/kernel/cpu/cpufreq/gx-suspmod.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/gx-suspmod.c
===================================================================
@@ -421,7 +421,6 @@ static int cpufreq_gx_cpu_init(struct cp
 		policy->min = maxfreq / POLICY_MIN_DIV;
 	policy->max = maxfreq;
 	policy->cur = curfreq;
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = maxfreq / max_duration;
 	policy->cpuinfo.max_freq = maxfreq;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;

arch/i386/kernel/cpu/cpufreq/longhaul.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/longhaul.c
===================================================================
@@ -802,7 +802,6 @@ print_support_type:
 	if ((longhaul_version != TYPE_LONGHAUL_V1) && (scale_voltage != 0))
 		longhaul_setup_voltagescaling();
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 200000;	/* nsec */
 	policy->cur = calc_speed(longhaul_get_cpu_mult());

arch/i386/kernel/cpu/cpufreq/p4-clockmod.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/p4-clockmod.c
===================================================================
@@ -229,7 +229,6 @@ static int cpufreq_p4_cpu_init(struct cp
 	cpufreq_frequency_table_get_attr(p4clockmod_table, policy->cpu);
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 1000000; /* assumed */
 	policy->cur = stock_freq;

arch/i386/kernel/cpu/cpufreq/powernow-k6.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/powernow-k6.c
===================================================================
@@ -160,7 +160,6 @@ static int powernow_k6_cpu_init(struct c
 	}
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = busfreq * max_multiplier;

arch/i386/kernel/cpu/cpufreq/powernow-k7.c +0 -2

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
===================================================================
@@ -637,8 +637,6 @@ static int __init powernow_cpu_init (str
 	printk (KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
 				minimum_speed/1000, maximum_speed/1000);
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cpuinfo.transition_latency = cpufreq_scale(2000000UL, fsb, latency);
 
 	policy->cur = powernow_get(0);

arch/i386/kernel/cpu/cpufreq/sc520_freq.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/sc520_freq.c
===================================================================
@@ -111,7 +111,6 @@ static int sc520_freq_cpu_init(struct cp
 		return -ENODEV;
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 1000000; /* 1ms */
 	policy->cur = sc520_freq_get_cpu_frequency(0);

arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
===================================================================
@@ -610,7 +610,6 @@ static int centrino_cpu_init(struct cpuf
 
 	freq = get_cur_freq(policy->cpu);
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 10000; /* 10uS transition latency */
 	policy->cur = freq;

arch/i386/kernel/cpu/cpufreq/speedstep-ich.c +0 -1

Index: linux-2.6.22-rc6/arch/i386/kernel/cpu/cpufreq/speedstep-ich.c
===================================================================
@@ -350,7 +350,6 @@ static int speedstep_cpu_init(struct cpu
 		(speed / 1000));
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cur = speed;
 
 	result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs);

drivers/cpufreq/cpufreq_conservative.c +5 -7

Index: linux-2.6.22-rc6/drivers/cpufreq/cpufreq_conservative.c
===================================================================
@@ -58,7 +58,7 @@ static unsigned int 				def_sampling_rat
 #define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER	(1000)
 #define DEF_SAMPLING_DOWN_FACTOR		(1)
 #define MAX_SAMPLING_DOWN_FACTOR		(10)
-#define TRANSITION_LATENCY_LIMIT		(10 * 1000)
+#define TRANSITION_LATENCY_LIMIT		(10 * 1000 * 1000)
 
 static void do_dbs_timer(struct work_struct *work);

@@ -466,9 +466,6 @@ static int cpufreq_governor_dbs(struct c
 		    (!policy->cur))
 			return -EINVAL;
 
-		if (policy->cpuinfo.transition_latency >
-				(TRANSITION_LATENCY_LIMIT * 1000))
-			return -EINVAL;
 		if (this_dbs_info->enable) /* Already enabled */
 			break;

@@ -552,9 +549,10 @@ static int cpufreq_governor_dbs(struct c
 }
 
 static struct cpufreq_governor cpufreq_gov_dbs = {
-	.name		= "conservative",
-	.governor	= cpufreq_governor_dbs,
-	.owner		= THIS_MODULE,
+	.name			= "conservative",
+	.governor		= cpufreq_governor_dbs,
+	.max_transition_latency	= TRANSITION_LATENCY_LIMIT,
+	.owner			= THIS_MODULE,
 };
 
 static int __init cpufreq_gov_dbs_init(void)

arch/arm/mach-imx/cpufreq.c +0 -1

Index: linux-2.6.22-rc6/arch/arm/mach-imx/cpufreq.c
===================================================================
@@ -269,7 +269,6 @@ static int __init imx_cpufreq_driver_ini
 		return -EINVAL;
 
 	policy->cur = policy->min = policy->max = imx_get_speed(0);
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = 8000;
 	policy->cpuinfo.max_freq = 200000;
 	 /* Manual states, that PLL stabilizes in two CLK32 periods */

arch/arm/mach-sa1100/cpu-sa1110.c +0 -1

Index: linux-2.6.22-rc6/arch/arm/mach-sa1100/cpu-sa1110.c
===================================================================
@@ -331,7 +331,6 @@ static int __init sa1110_cpu_init(struct
 	if (policy->cpu != 0)
 		return -EINVAL;
 	policy->cur = policy->min = policy->max = sa11x0_getspeed(0);
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = 59000;
 	policy->cpuinfo.max_freq = 287000;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;

arch/arm/plat-omap/cpu-omap.c +0 -1

Index: linux-2.6.22-rc6/arch/arm/plat-omap/cpu-omap.c
===================================================================
@@ -108,7 +108,6 @@ static int __init omap_cpu_init(struct c
 	if (policy->cpu != 0)
 		return -EINVAL;
 	policy->cur = policy->min = policy->max = omap_getspeed(0);
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = clk_round_rate(mpu_clk, 0) / 1000;
 	policy->cpuinfo.max_freq = clk_round_rate(mpu_clk, VERY_HI_RATE) / 1000;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;

arch/blackfin/mach-bf533/cpu.c +0 -2

Index: linux-2.6.22-rc6/arch/blackfin/mach-bf533/cpu.c
===================================================================
@@ -119,8 +119,6 @@ static int __init __bf533_cpu_init(struc
 	if (policy->cpu != 0)
 		return -EINVAL;
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	/*Now ,only support one cpu */
 	policy->cur = bf533_getfreq(0);

arch/ia64/kernel/cpufreq/acpi-cpufreq.c +0 -2

Index: linux-2.6.22-rc6/arch/ia64/kernel/cpufreq/acpi-cpufreq.c
===================================================================
@@ -323,8 +323,6 @@ acpi_cpufreq_cpu_init (
 			    data->acpi_data.states[i].transition_latency * 1000;
 		}
 	}
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cur = processor_get_freq(data, policy->cpu);
 
 	/* table init */

arch/powerpc/platforms/cell/cbe_cpufreq.c +0 -1

Index: linux-2.6.22-rc6/arch/powerpc/platforms/cell/cbe_cpufreq.c
===================================================================
@@ -235,7 +235,6 @@ static int cbe_cpufreq_cpu_init(struct c
 		pr_debug("%d: %d\n", i, cbe_freqs[i].frequency);
 	}
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	/* if DEBUG is enabled set_pmode() measures the correct latency of a transition */
 	policy->cpuinfo.transition_latency = 25000;

arch/powerpc/platforms/pasemi/cpufreq.c +0 -2

Index: linux-2.6.22-rc6/arch/powerpc/platforms/pasemi/cpufreq.c
===================================================================
@@ -195,8 +195,6 @@ static int pas_cpufreq_cpu_init(struct c
 		pr_debug("%d: %d\n", i, pas_freqs[i].frequency);
 	}
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cpuinfo.transition_latency = get_gizmo_latency();
 
 	cur_astate = get_cur_astate(policy->cpu);

arch/powerpc/platforms/powermac/cpufreq_32.c +0 -1

Index: linux-2.6.22-rc6/arch/powerpc/platforms/powermac/cpufreq_32.c
===================================================================
@@ -410,7 +410,6 @@ static int pmac_cpufreq_cpu_init(struct 
 	if (policy->cpu != 0)
 		return -ENODEV;
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency	= CPUFREQ_ETERNAL;
 	policy->cur = cur_freq;

arch/powerpc/platforms/powermac/cpufreq_64.c +0 -1

Index: linux-2.6.22-rc6/arch/powerpc/platforms/powermac/cpufreq_64.c
===================================================================
@@ -357,7 +357,6 @@ static unsigned int g5_cpufreq_get_speed
 
 static int g5_cpufreq_cpu_init(struct cpufreq_policy *policy)
 {
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = g5_cpu_freqs[g5_query_freq()].frequency;
 	/* secondary CPUs are tied to the primary one by the

arch/sh/kernel/cpufreq.c +0 -1

Index: linux-2.6.22-rc6/arch/sh/kernel/cpufreq.c
===================================================================
@@ -159,7 +159,6 @@ static int sh_cpufreq_cpu_init(struct cp
 	sh_freqs[SH_FREQ_MIN].frequency = min_freq;
 
 	/* cpuinfo and default policy values */
-	policy->governor                   = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur                        = max_freq;

arch/sparc64/kernel/us2e_cpufreq.c +0 -1

Index: linux-2.6.22-rc6/arch/sparc64/kernel/us2e_cpufreq.c
===================================================================
@@ -326,7 +326,6 @@ static int __init us2e_freq_cpu_init(str
 	table[2].index = 5;
 	table[3].frequency = CPUFREQ_TABLE_END;
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 0;
 	policy->cur = clock_tick;

Dave Jones

2007-07-13 05:32 UTC #1 lore raw

Quoted 6 lines · Thomas Renninger

Hi Venkatesh,
do you give me your ack/signed off for this one?
Runtime tested to load ondemand and to fallback to performance governor (by faking the transition latency of the driver) on x86_64.

I couldn't even get this to build with defconfig, which doesn't inspire confidence..

defconfig x86-64 creates..

CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set # CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set # CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
# CONFIG_CPU_FREQ_GOV_POWERSAVE is not set CONFIG_CPU_FREQ_GOV_USERSPACE=y CONFIG_CPU_FREQ_GOV_ONDEMAND=y
# CONFIG_CPU_FREQ_GOV_CONSERVATIVE is not set

and the build fails thus ..

drivers/cpufreq/cpufreq.c: In function ‘__cpufreq_governor’:
drivers/cpufreq/cpufreq.c:1495: error: expected ‘)’ before ‘;’ token drivers/cpufreq/cpufreq.c:1495: warning: format ‘%s’ expects type ‘char *’, but argument 3 has type ‘struct cpufreq_governor *’

line 1495 is ..

1488 if (policy->governor->max_transition_latency &&
1489 policy->cpuinfo.transition_latency >
1490 policy->governor->max_transition_latency) {
1491 printk(KERN_WARNING "%s governor failed, too long"

1492                        " transition latency of HW, fallback"
1493                        " to %s governor\n",
1494                        policy->governor->name,
1495                        CPUFREQ_PERFORMANCE_GOVERNOR->name);

1496 policy->governor = CPUFREQ_PERFORMANCE_GOVERNOR;
1497 }

CPUFREQ_PERFORMANCE_GOVERNOR is defined as ..

#define CPUFREQ_PERFORMANCE_GOVERNOR &cpufreq_gov_performance;

which clearly isn't going to work. Changing it to ..

#define CPUFREQ_PERFORMANCE_GOVERNOR (&cpufreq_gov_performance)

gets it building again.
Looks like the conservative define a few lines down might have the same issue.

I'm going to drop this for now and turn in for the night, but if you can get me an updated patch against cpufreq-git that's been tested in a few more configurations, I'll see if I can get it with the next batch that goes to Linus sometime soon before the merge window closes.

Thanks,

Dave

Signature · 1 line

http://www.codemonkey.org.uk

Thomas Renninger

author

2007-07-13 16:17 UTC #2 lore raw

Quoted 5 lines · Dave Jones

Quoted 4 lines · Thomas Renninger
Hi Venkatesh,
do you give me your ack/signed off for this one?

...

Quoted 7 lines

CPUFREQ_PERFORMANCE_GOVERNOR is defined as ..
#define CPUFREQ_PERFORMANCE_GOVERNOR &cpufreq_gov_performance;
which clearly isn't going to work. Changing it to ..
#define CPUFREQ_PERFORMANCE_GOVERNOR (&cpufreq_gov_performance)

This is a good idea -> will define all in that way. I modified the msg quite late, sorry about that.

Quoted 8 lines

gets it building again.
Looks like the conservative define a few lines down might have the same issue.
I'm going to drop this for now and turn in for the night, but if you can get me an updated patch against cpufreq-git that's been tested in a few more configurations, I'll see if I can get it with the next batch that goes to Linus sometime soon before the merge window closes.

I'd like to have a comment from Venkatesh.
He is back on 15 July and has to read up mails from a month...

Attached is a patch, just doing the change you suggested for the defines, should build fine now (I have tried at least different archs with the previous patch and working msg).

If Venkatesh answers or you give me a final date, I can rebase this against latest cpufreq-git branch, do some more tests and send it again.

This one should build with 2.6.22.1 now, if anyone likes to give it a try, that is appreciated.

Thanks,

Thomas

Allow ondemand and conservative cpufreq governors to be used as default

Signed-off-by Thomas Renninger <[email protected]>

---
 arch/arm/mach-imx/cpufreq.c                       |    1 
 arch/arm/mach-sa1100/cpu-sa1110.c                 |    1 
 arch/arm/plat-omap/cpu-omap.c                     |    1 
 arch/blackfin/mach-bf533/cpu.c                    |    2 -
 arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c       |    1 
 arch/i386/kernel/cpu/cpufreq/cpufreq-nforce2.c    |    1 
 arch/i386/kernel/cpu/cpufreq/e_powersaver.c       |    1 
 arch/i386/kernel/cpu/cpufreq/elanfreq.c           |    1 
 arch/i386/kernel/cpu/cpufreq/gx-suspmod.c         |    1 
 arch/i386/kernel/cpu/cpufreq/longhaul.c           |    1 
 arch/i386/kernel/cpu/cpufreq/p4-clockmod.c        |    1 
 arch/i386/kernel/cpu/cpufreq/powernow-k6.c        |    1 
 arch/i386/kernel/cpu/cpufreq/powernow-k7.c        |    2 -
 arch/i386/kernel/cpu/cpufreq/powernow-k8.c        |    1 
 arch/i386/kernel/cpu/cpufreq/sc520_freq.c         |    1 
 arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c |    1 
 arch/i386/kernel/cpu/cpufreq/speedstep-ich.c      |    1 
 arch/i386/kernel/cpu/cpufreq/speedstep-smi.c      |    1 
 arch/ia64/kernel/cpufreq/acpi-cpufreq.c           |    2 -
 arch/powerpc/platforms/cell/cbe_cpufreq.c         |    1 
 arch/powerpc/platforms/pasemi/cpufreq.c           |    2 -
 arch/powerpc/platforms/powermac/cpufreq_32.c      |    1 
 arch/powerpc/platforms/powermac/cpufreq_64.c      |    1 
 arch/sh/kernel/cpufreq.c                          |    1 
 arch/sparc64/kernel/us2e_cpufreq.c                |    1 
 drivers/cpufreq/Kconfig                           |   23 ++++++++++++++++++----
 drivers/cpufreq/cpufreq.c                         |   14 +++++++++++++
 drivers/cpufreq/cpufreq_conservative.c            |   12 ++++-------
 drivers/cpufreq/cpufreq_ondemand.c                |   22 ++++++++-------------
 include/linux/cpufreq.h                           |   20 ++++++++++++++++---
 30 files changed, 64 insertions(+), 56 deletions(-)

arch/i386/kernel/cpu/cpufreq/powernow-k8.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
===================================================================
@@ -1205,7 +1205,6 @@ static int __cpuinit powernowk8_cpu_init
 	/* run on any CPU again */
 	set_cpus_allowed(current, oldmask);
 
-	pol->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	if (cpu_family == CPU_HW_PSTATE)
 		pol->cpus = cpumask_of_cpu(pol->cpu);
 	else

drivers/cpufreq/cpufreq_ondemand.c +9 ~~-13~~

Index: linux-2.6.22.1/drivers/cpufreq/cpufreq_ondemand.c
===================================================================
@@ -47,7 +47,7 @@ static unsigned int def_sampling_rate;
 			(def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
 #define MAX_SAMPLING_RATE			(500 * def_sampling_rate)
 #define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER	(1000)
-#define TRANSITION_LATENCY_LIMIT		(10 * 1000)
+#define TRANSITION_LATENCY_LIMIT		(10 * 1000 * 1000)
 
 static void do_dbs_timer(struct work_struct *work);

@@ -496,12 +496,6 @@ static int cpufreq_governor_dbs(struct c
 		if ((!cpu_online(cpu)) || (!policy->cur))
 			return -EINVAL;
 
-		if (policy->cpuinfo.transition_latency >
-				(TRANSITION_LATENCY_LIMIT * 1000)) {
-			printk(KERN_WARNING "ondemand governor failed to load "
-			       "due to too long transition latency\n");
-			return -EINVAL;
-		}
 		if (this_dbs_info->enable) /* Already enabled */
 			break;

@@ -573,11 +567,13 @@ static int cpufreq_governor_dbs(struct c
 	return 0;
 }
 
-static struct cpufreq_governor cpufreq_gov_dbs = {
-	.name = "ondemand",
-	.governor = cpufreq_governor_dbs,
-	.owner = THIS_MODULE,
+struct cpufreq_governor cpufreq_gov_ondemand = {
+	.name			= "ondemand",
+	.governor		= cpufreq_governor_dbs,
+	.max_transition_latency = TRANSITION_LATENCY_LIMIT,
+	.owner			= THIS_MODULE,
 };
+EXPORT_SYMBOL(cpufreq_gov_ondemand);
 
 static int __init cpufreq_gov_dbs_init(void)
 {

@@ -586,12 +582,12 @@ static int __init cpufreq_gov_dbs_init(v
 		printk(KERN_ERR "Creation of kondemand failed\n");
 		return -EFAULT;
 	}
-	return cpufreq_register_governor(&cpufreq_gov_dbs);
+	return cpufreq_register_governor(&cpufreq_gov_ondemand);
 }
 
 static void __exit cpufreq_gov_dbs_exit(void)
 {
-	cpufreq_unregister_governor(&cpufreq_gov_dbs);
+	cpufreq_unregister_governor(&cpufreq_gov_ondemand);
 	destroy_workqueue(kondemand_wq);
 }

include/linux/cpufreq.h +17 -3

Index: linux-2.6.22.1/include/linux/cpufreq.h
===================================================================
@@ -163,6 +163,9 @@ struct cpufreq_governor {
 	char	name[CPUFREQ_NAME_LEN];
 	int 	(*governor)	(struct cpufreq_policy *policy,
 				 unsigned int event);
+	unsigned int max_transition_latency; /* HW must be able to switch to
+			next freq faster than this value in nano secs or we
+			will fallback to performance governor */
 	struct list_head	governor_list;
 	struct module		*owner;
 };

@@ -292,12 +295,23 @@ static inline unsigned int cpufreq_get(u
  *********************************************************************/
 
 
-#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
+/*
+  Performance governor is fallback governor if any other gov failed to
+  auto load due latency restrictions
+*/
 extern struct cpufreq_governor cpufreq_gov_performance;
-#define CPUFREQ_DEFAULT_GOVERNOR	&cpufreq_gov_performance
+#define CPUFREQ_PERFORMANCE_GOVERNOR	(&cpufreq_gov_performance)
+#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
+#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_performance)
 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
 extern struct cpufreq_governor cpufreq_gov_userspace;
-#define CPUFREQ_DEFAULT_GOVERNOR	&cpufreq_gov_userspace
+#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_userspace)
+#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
+extern struct cpufreq_governor cpufreq_gov_ondemand;
+#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_ondemand)
+#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
+extern struct cpufreq_governor cpufreq_gov_conservative;
+#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_conservative)
 #endif

drivers/cpufreq/Kconfig +19 -4

Index: linux-2.6.22.1/drivers/cpufreq/Kconfig
===================================================================
@@ -56,10 +56,6 @@ config CPU_FREQ_STAT_DETAILS
 
 	  If in doubt, say N.
 
-# Note that it is not currently possible to set the other governors (such as ondemand)
-# as the default, since if they fail to initialise, cpufreq will be
-# left in an undefined state.
-
 choice
 	prompt "Default CPUFreq governor"
 	default CPU_FREQ_DEFAULT_GOV_USERSPACE if CPU_FREQ_SA1100 || CPU_FREQ_SA1110

@@ -85,6 +81,25 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE
 	  program shall be able to set the CPU dynamically without having
 	  to enable the userspace governor manually.
 
+config CPU_FREQ_DEFAULT_GOV_ONDEMAND
+	bool "ondemand"
+	select CPU_FREQ_GOV_ONDEMAND
+	select CPU_FREQ_GOV_PERFORMANCE
+	help
+	  Use the CPUFreq governor 'ondemand' as default. This allows
+	  you to get a full dynamic frequncy capable system by simply
+	  loading your cpufreq driver.
+	  Be aware that not all cpufreq drivers support the ondemand
+	  governor. If unsure have a look at the help section of the
+	  driver. Fallback governor will then be the performance
+	  governor.
+
+config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
+	bool "conservative"
+	select CPU_FREQ_GOV_CONSERVATIVE
+	select CPU_FREQ_GOV_PERFORMANCE
+	help
+	  See ondemand as default governor help above.
 endchoice
 
 config CPU_FREQ_GOV_PERFORMANCE

arch/i386/kernel/cpu/cpufreq/speedstep-smi.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c
===================================================================
@@ -290,7 +290,6 @@ static int speedstep_cpu_init(struct cpu
 		(speed / 1000));
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = speed;

drivers/cpufreq/cpufreq.c +14 -0

Index: linux-2.6.22.1/drivers/cpufreq/cpufreq.c
===================================================================
@@ -759,6 +759,8 @@ static int cpufreq_add_dev (struct sys_d
 	init_completion(&policy->kobj_unregister);
 	INIT_WORK(&policy->update, handle_update);
 
+	/* Set governor before ->init, so that driver could check it */
+	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	/* call driver. From then on the cpufreq must be able
 	 * to accept all calls to ->verify and ->setpolicy for this CPU
 	 */

@@ -1453,6 +1455,18 @@ static int __cpufreq_governor(struct cpu
 					unsigned int event)
 {
 	int ret;
+	struct cpufreq_governor *gov = CPUFREQ_PERFORMANCE_GOVERNOR;
+
+	if (policy->governor->max_transition_latency &&
+	    policy->cpuinfo.transition_latency >
+	    policy->governor->max_transition_latency) {
+		printk(KERN_WARNING "%s governor failed, too long"
+		       " transition latency of HW, fallback"
+		       " to %s governor\n",
+		       policy->governor->name,
+		       gov->name);
+		       policy->governor = gov;
+	}
 
 	if (!try_module_get(policy->governor->owner))
 		return -EINVAL;

arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
===================================================================
@@ -663,7 +663,6 @@ static int acpi_cpufreq_cpu_init(struct 
 			policy->cpuinfo.transition_latency =
 			    perf->states[i].transition_latency * 1000;
 	}
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 
 	data->max_freq = perf->states[0].core_frequency * 1000;
 	/* table init */

arch/i386/kernel/cpu/cpufreq/cpufreq-nforce2.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/cpufreq-nforce2.c
===================================================================
@@ -363,7 +363,6 @@ static int nforce2_cpu_init(struct cpufr
 	policy->cur = nforce2_get(policy->cpu);
 	policy->min = policy->cpuinfo.min_freq;
 	policy->max = policy->cpuinfo.max_freq;
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 
 	return 0;
 }

arch/i386/kernel/cpu/cpufreq/e_powersaver.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/e_powersaver.c
===================================================================
@@ -253,7 +253,6 @@ static int eps_cpu_init(struct cpufreq_p
 		f_table[k].frequency = CPUFREQ_TABLE_END;
 	}
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 140000; /* 844mV -> 700mV in ns */
 	policy->cur = fsb * current_multiplier;

arch/i386/kernel/cpu/cpufreq/elanfreq.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/elanfreq.c
===================================================================
@@ -219,7 +219,6 @@ static int elanfreq_cpu_init(struct cpuf
 	}
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = elanfreq_get_cpu_frequency(0);

arch/i386/kernel/cpu/cpufreq/gx-suspmod.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/gx-suspmod.c
===================================================================
@@ -421,7 +421,6 @@ static int cpufreq_gx_cpu_init(struct cp
 		policy->min = maxfreq / POLICY_MIN_DIV;
 	policy->max = maxfreq;
 	policy->cur = curfreq;
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = maxfreq / max_duration;
 	policy->cpuinfo.max_freq = maxfreq;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;

arch/i386/kernel/cpu/cpufreq/longhaul.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/longhaul.c
===================================================================
@@ -802,7 +802,6 @@ print_support_type:
 	if ((longhaul_version != TYPE_LONGHAUL_V1) && (scale_voltage != 0))
 		longhaul_setup_voltagescaling();
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 200000;	/* nsec */
 	policy->cur = calc_speed(longhaul_get_cpu_mult());

arch/i386/kernel/cpu/cpufreq/p4-clockmod.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/p4-clockmod.c
===================================================================
@@ -229,7 +229,6 @@ static int cpufreq_p4_cpu_init(struct cp
 	cpufreq_frequency_table_get_attr(p4clockmod_table, policy->cpu);
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 1000000; /* assumed */
 	policy->cur = stock_freq;

arch/i386/kernel/cpu/cpufreq/powernow-k6.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/powernow-k6.c
===================================================================
@@ -160,7 +160,6 @@ static int powernow_k6_cpu_init(struct c
 	}
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = busfreq * max_multiplier;

arch/i386/kernel/cpu/cpufreq/powernow-k7.c +0 -2

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
===================================================================
@@ -637,8 +637,6 @@ static int __init powernow_cpu_init (str
 	printk (KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
 				minimum_speed/1000, maximum_speed/1000);
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cpuinfo.transition_latency = cpufreq_scale(2000000UL, fsb, latency);
 
 	policy->cur = powernow_get(0);

arch/i386/kernel/cpu/cpufreq/sc520_freq.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/sc520_freq.c
===================================================================
@@ -111,7 +111,6 @@ static int sc520_freq_cpu_init(struct cp
 		return -ENODEV;
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 1000000; /* 1ms */
 	policy->cur = sc520_freq_get_cpu_frequency(0);

arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
===================================================================
@@ -610,7 +610,6 @@ static int centrino_cpu_init(struct cpuf
 
 	freq = get_cur_freq(policy->cpu);
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 10000; /* 10uS transition latency */
 	policy->cur = freq;

arch/i386/kernel/cpu/cpufreq/speedstep-ich.c +0 -1

Index: linux-2.6.22.1/arch/i386/kernel/cpu/cpufreq/speedstep-ich.c
===================================================================
@@ -350,7 +350,6 @@ static int speedstep_cpu_init(struct cpu
 		(speed / 1000));
 
 	/* cpuinfo and default policy values */
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cur = speed;
 
 	result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs);

drivers/cpufreq/cpufreq_conservative.c +5 -7

Index: linux-2.6.22.1/drivers/cpufreq/cpufreq_conservative.c
===================================================================
@@ -58,7 +58,7 @@ static unsigned int 				def_sampling_rat
 #define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER	(1000)
 #define DEF_SAMPLING_DOWN_FACTOR		(1)
 #define MAX_SAMPLING_DOWN_FACTOR		(10)
-#define TRANSITION_LATENCY_LIMIT		(10 * 1000)
+#define TRANSITION_LATENCY_LIMIT		(10 * 1000 * 1000)
 
 static void do_dbs_timer(struct work_struct *work);

@@ -466,9 +466,6 @@ static int cpufreq_governor_dbs(struct c
 		    (!policy->cur))
 			return -EINVAL;
 
-		if (policy->cpuinfo.transition_latency >
-				(TRANSITION_LATENCY_LIMIT * 1000))
-			return -EINVAL;
 		if (this_dbs_info->enable) /* Already enabled */
 			break;

@@ -552,9 +549,10 @@ static int cpufreq_governor_dbs(struct c
 }
 
 static struct cpufreq_governor cpufreq_gov_dbs = {
-	.name		= "conservative",
-	.governor	= cpufreq_governor_dbs,
-	.owner		= THIS_MODULE,
+	.name			= "conservative",
+	.governor		= cpufreq_governor_dbs,
+	.max_transition_latency	= TRANSITION_LATENCY_LIMIT,
+	.owner			= THIS_MODULE,
 };
 
 static int __init cpufreq_gov_dbs_init(void)

arch/arm/mach-imx/cpufreq.c +0 -1

Index: linux-2.6.22.1/arch/arm/mach-imx/cpufreq.c
===================================================================
@@ -269,7 +269,6 @@ static int __init imx_cpufreq_driver_ini
 		return -EINVAL;
 
 	policy->cur = policy->min = policy->max = imx_get_speed(0);
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = 8000;
 	policy->cpuinfo.max_freq = 200000;
 	 /* Manual states, that PLL stabilizes in two CLK32 periods */

arch/arm/mach-sa1100/cpu-sa1110.c +0 -1

Index: linux-2.6.22.1/arch/arm/mach-sa1100/cpu-sa1110.c
===================================================================
@@ -331,7 +331,6 @@ static int __init sa1110_cpu_init(struct
 	if (policy->cpu != 0)
 		return -EINVAL;
 	policy->cur = policy->min = policy->max = sa11x0_getspeed(0);
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = 59000;
 	policy->cpuinfo.max_freq = 287000;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;

arch/arm/plat-omap/cpu-omap.c +0 -1

Index: linux-2.6.22.1/arch/arm/plat-omap/cpu-omap.c
===================================================================
@@ -108,7 +108,6 @@ static int __init omap_cpu_init(struct c
 	if (policy->cpu != 0)
 		return -EINVAL;
 	policy->cur = policy->min = policy->max = omap_getspeed(0);
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.min_freq = clk_round_rate(mpu_clk, 0) / 1000;
 	policy->cpuinfo.max_freq = clk_round_rate(mpu_clk, VERY_HI_RATE) / 1000;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;

arch/blackfin/mach-bf533/cpu.c +0 -2

Index: linux-2.6.22.1/arch/blackfin/mach-bf533/cpu.c
===================================================================
@@ -119,8 +119,6 @@ static int __init __bf533_cpu_init(struc
 	if (policy->cpu != 0)
 		return -EINVAL;
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	/*Now ,only support one cpu */
 	policy->cur = bf533_getfreq(0);

arch/ia64/kernel/cpufreq/acpi-cpufreq.c +0 -2

Index: linux-2.6.22.1/arch/ia64/kernel/cpufreq/acpi-cpufreq.c
===================================================================
@@ -323,8 +323,6 @@ acpi_cpufreq_cpu_init (
 			    data->acpi_data.states[i].transition_latency * 1000;
 		}
 	}
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cur = processor_get_freq(data, policy->cpu);
 
 	/* table init */

arch/powerpc/platforms/cell/cbe_cpufreq.c +0 -1

Index: linux-2.6.22.1/arch/powerpc/platforms/cell/cbe_cpufreq.c
===================================================================
@@ -238,7 +238,6 @@ static int cbe_cpufreq_cpu_init(struct c
 		pr_debug("%d: %d\n", i, cbe_freqs[i].frequency);
 	}
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	/* if DEBUG is enabled set_pmode() measures the correct latency of a transition */
 	policy->cpuinfo.transition_latency = 25000;

arch/powerpc/platforms/pasemi/cpufreq.c +0 -2

Index: linux-2.6.22.1/arch/powerpc/platforms/pasemi/cpufreq.c
===================================================================
@@ -195,8 +195,6 @@ static int pas_cpufreq_cpu_init(struct c
 		pr_debug("%d: %d\n", i, pas_freqs[i].frequency);
 	}
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-
 	policy->cpuinfo.transition_latency = get_gizmo_latency();
 
 	cur_astate = get_cur_astate(policy->cpu);

arch/powerpc/platforms/powermac/cpufreq_32.c +0 -1

Index: linux-2.6.22.1/arch/powerpc/platforms/powermac/cpufreq_32.c
===================================================================
@@ -410,7 +410,6 @@ static int pmac_cpufreq_cpu_init(struct 
 	if (policy->cpu != 0)
 		return -ENODEV;
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency	= CPUFREQ_ETERNAL;
 	policy->cur = cur_freq;

arch/powerpc/platforms/powermac/cpufreq_64.c +0 -1

Index: linux-2.6.22.1/arch/powerpc/platforms/powermac/cpufreq_64.c
===================================================================
@@ -357,7 +357,6 @@ static unsigned int g5_cpufreq_get_speed
 
 static int g5_cpufreq_cpu_init(struct cpufreq_policy *policy)
 {
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = g5_cpu_freqs[g5_query_freq()].frequency;
 	/* secondary CPUs are tied to the primary one by the

arch/sh/kernel/cpufreq.c +0 -1

Index: linux-2.6.22.1/arch/sh/kernel/cpufreq.c
===================================================================
@@ -159,7 +159,6 @@ static int sh_cpufreq_cpu_init(struct cp
 	sh_freqs[SH_FREQ_MIN].frequency = min_freq;
 
 	/* cpuinfo and default policy values */
-	policy->governor                   = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur                        = max_freq;

arch/sparc64/kernel/us2e_cpufreq.c +0 -1

Index: linux-2.6.22.1/arch/sparc64/kernel/us2e_cpufreq.c
===================================================================
@@ -326,7 +326,6 @@ static int __init us2e_freq_cpu_init(str
 	table[2].index = 5;
 	table[3].frequency = CPUFREQ_TABLE_END;
 
-	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 	policy->cpuinfo.transition_latency = 0;
 	policy->cur = clock_tick;