Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq

Documentation/cpu-freq/governors.txt

@@ -27,6 +27,7 @@ Contents:
 2.2  Powersave
 2.3  Userspace
 2.4  Ondemand
+2.5  Conservative
 
 3.   The Governor Interface in the CPUfreq Core
 
@@ -110,9 +111,64 @@ directory.
 
 The CPUfreq govenor "ondemand" sets the CPU depending on the
 current usage. To do this the CPU must have the capability to
-switch the frequency very fast.
-
-
+switch the frequency very quickly.  There are a number of sysfs file
+accessible parameters:
+
+sampling_rate: measured in uS (10^-6 seconds), this is how often you
+want the kernel to look at the CPU usage and to make decisions on
+what to do about the frequency.  Typically this is set to values of
+around '10000' or more.
+
+show_sampling_rate_(min|max): the minimum and maximum sampling rates
+available that you may set 'sampling_rate' to.
+
+up_threshold: defines what the average CPU usaged between the samplings
+of 'sampling_rate' needs to be for the kernel to make a decision on
+whether it should increase the frequency.  For example when it is set
+to its default value of '80' it means that between the checking
+intervals the CPU needs to be on average more than 80% in use to then
+decide that the CPU frequency needs to be increased.  
+
+sampling_down_factor: this parameter controls the rate that the CPU
+makes a decision on when to decrease the frequency.  When set to its
+default value of '5' it means that at 1/5 the sampling_rate the kernel
+makes a decision to lower the frequency.  Five "lower rate" decisions
+have to be made in a row before the CPU frequency is actually lower.
+If set to '1' then the frequency decreases as quickly as it increases,
+if set to '2' it decreases at half the rate of the increase.
+
+ignore_nice_load: this parameter takes a value of '0' or '1', when set
+to '0' (its default) then all processes are counted towards towards the
+'cpu utilisation' value.   When set to '1' then processes that are
+run with a 'nice' value will not count (and thus be ignored) in the
+overal usage calculation.  This is useful if you are running a CPU
+intensive calculation on your laptop that you do not care how long it
+takes to complete as you can 'nice' it and prevent it from taking part
+in the deciding process of whether to increase your CPU frequency.
+
+
+2.5 Conservative
+----------------
+
+The CPUfreq governor "conservative", much like the "ondemand"
+governor, sets the CPU depending on the current usage.  It differs in
+behaviour in that it gracefully increases and decreases the CPU speed
+rather than jumping to max speed the moment there is any load on the
+CPU.  This behaviour more suitable in a battery powered environment.
+The governor is tweaked in the same manner as the "ondemand" governor
+through sysfs with the addition of:
+
+freq_step: this describes what percentage steps the cpu freq should be
+increased and decreased smoothly by.  By default the cpu frequency will
+increase in 5% chunks of your maximum cpu frequency.  You can change this
+value to anywhere between 0 and 100 where '0' will effectively lock your
+CPU at a speed regardless of its load whilst '100' will, in theory, make
+it behave identically to the "ondemand" governor.
+
+down_threshold: same as the 'up_threshold' found for the "ondemand"
+governor but for the opposite direction.  For example when set to its
+default value of '20' it means that if the CPU usage needs to be below
+20% between samples to have the frequency decreased.
 
 3. The Governor Interface in the CPUfreq Core
 =============================================

arch/i386/kernel/cpu/cpufreq/cpufreq-nforce2.c

@@ -177,9 +177,10 @@ static unsigned int nforce2_fsb_read(int bootfsb)
  */
 static int nforce2_set_fsb(unsigned int fsb)
 {
-	u32 pll, temp = 0;
+	u32 temp = 0;
 	unsigned int tfsb;
 	int diff;
+	int pll = 0;
 
 	if ((fsb > max_fsb) || (fsb < NFORCE2_MIN_FSB)) {
 		printk(KERN_ERR "cpufreq: FSB %d is out of range!\n", fsb);

arch/i386/kernel/cpu/cpufreq/powernow-k8.c

@@ -45,7 +45,7 @@
 
 #define PFX "powernow-k8: "
 #define BFX PFX "BIOS error: "
-#define VERSION "version 1.50.4"
+#define VERSION "version 1.60.0"
 #include "powernow-k8.h"
 
 /* serialize freq changes  */
@@ -216,10 +216,10 @@ static int write_new_vid(struct powernow_k8_data *data, u32 vid)
 
 	do {
 		wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
-                if (i++ > 100) {
-                        printk(KERN_ERR PFX "internal error - pending bit very stuck - no further pstate changes possible\n");
-                        return 1;
-                }
+		if (i++ > 100) {
+			printk(KERN_ERR PFX "internal error - pending bit very stuck - no further pstate changes possible\n");
+			return 1;
+		}
 	} while (query_current_values_with_pending_wait(data));
 
 	if (savefid != data->currfid) {
@@ -336,7 +336,7 @@ static int core_voltage_pre_transition(struct powernow_k8_data *data, u32 reqvid
 /* Phase 2 - core frequency transition */
 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 {
-	u32 vcoreqfid, vcocurrfid, vcofiddiff, savevid = data->currvid;
+	u32 vcoreqfid, vcocurrfid, vcofiddiff, fid_interval, savevid = data->currvid;
 
 	if ((reqfid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
 		printk(KERN_ERR PFX "ph2: illegal lo-lo transition 0x%x 0x%x\n",
@@ -359,9 +359,11 @@ static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 	    : vcoreqfid - vcocurrfid;
 
 	while (vcofiddiff > 2) {
+		(data->currfid & 1) ? (fid_interval = 1) : (fid_interval = 2);
+
 		if (reqfid > data->currfid) {
 			if (data->currfid > LO_FID_TABLE_TOP) {
-				if (write_new_fid(data, data->currfid + 2)) {
+				if (write_new_fid(data, data->currfid + fid_interval)) {
 					return 1;
 				}
 			} else {
@@ -371,7 +373,7 @@ static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 				}
 			}
 		} else {
-			if (write_new_fid(data, data->currfid - 2))
+			if (write_new_fid(data, data->currfid - fid_interval))
 				return 1;
 		}
 
@@ -464,7 +466,7 @@ static int check_supported_cpu(unsigned int cpu)
 	set_cpus_allowed(current, cpumask_of_cpu(cpu));
 
 	if (smp_processor_id() != cpu) {
-		printk(KERN_ERR "limiting to cpu %u failed\n", cpu);
+		printk(KERN_ERR PFX "limiting to cpu %u failed\n", cpu);
 		goto out;
 	}
 
@@ -474,7 +476,7 @@ static int check_supported_cpu(unsigned int cpu)
 	eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 	if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
 	    ((eax & CPUID_XFAM) != CPUID_XFAM_K8) ||
-	    ((eax & CPUID_XMOD) > CPUID_XMOD_REV_F)) {
+	    ((eax & CPUID_XMOD) > CPUID_XMOD_REV_G)) {
 		printk(KERN_INFO PFX "Processor cpuid %x not supported\n", eax);
 		goto out;
 	}
@@ -517,22 +519,24 @@ static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst, u8
 			printk(KERN_ERR BFX "maxvid exceeded with pstate %d\n", j);
 			return -ENODEV;
 		}
-		if ((pst[j].fid > MAX_FID)
-		    || (pst[j].fid & 1)
-		    || (j && (pst[j].fid < HI_FID_TABLE_BOTTOM))) {
+		if (pst[j].fid > MAX_FID) {
+			printk(KERN_ERR BFX "maxfid exceeded with pstate %d\n", j);
+			return -ENODEV;
+		}
+		if (j && (pst[j].fid < HI_FID_TABLE_BOTTOM)) {
 			/* Only first fid is allowed to be in "low" range */
-			printk(KERN_ERR PFX "two low fids - %d : 0x%x\n", j, pst[j].fid);
+			printk(KERN_ERR BFX "two low fids - %d : 0x%x\n", j, pst[j].fid);
 			return -EINVAL;
 		}
 		if (pst[j].fid < lastfid)
 			lastfid = pst[j].fid;
 	}
 	if (lastfid & 1) {
-		printk(KERN_ERR PFX "lastfid invalid\n");
+		printk(KERN_ERR BFX "lastfid invalid\n");
 		return -EINVAL;
 	}
 	if (lastfid > LO_FID_TABLE_TOP)
-		printk(KERN_INFO PFX  "first fid not from lo freq table\n");
+		printk(KERN_INFO BFX  "first fid not from lo freq table\n");
 
 	return 0;
 }
@@ -631,7 +635,7 @@ static int find_psb_table(struct powernow_k8_data *data)
 
 		dprintk("table vers: 0x%x\n", psb->tableversion);
 		if (psb->tableversion != PSB_VERSION_1_4) {
-			printk(KERN_INFO BFX "PSB table is not v1.4\n");
+			printk(KERN_ERR BFX "PSB table is not v1.4\n");
 			return -ENODEV;
 		}
 
@@ -689,7 +693,7 @@ static int find_psb_table(struct powernow_k8_data *data)
 	 * BIOS and Kernel Developer's Guide, which is available on
 	 * www.amd.com
 	 */
-	printk(KERN_INFO PFX "BIOS error - no PSB or ACPI _PSS objects\n");
+	printk(KERN_ERR PFX "BIOS error - no PSB or ACPI _PSS objects\n");
 	return -ENODEV;
 }
 
@@ -912,7 +916,7 @@ static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsi
 	set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
 
 	if (smp_processor_id() != pol->cpu) {
-		printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
+		printk(KERN_ERR PFX "limiting to cpu %u failed\n", pol->cpu);
 		goto err_out;
 	}
 
@@ -982,6 +986,9 @@ static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
 	cpumask_t oldmask = CPU_MASK_ALL;
 	int rc, i;
 
+	if (!cpu_online(pol->cpu))
+		return -ENODEV;
+
 	if (!check_supported_cpu(pol->cpu))
 		return -ENODEV;
 
@@ -1021,7 +1028,7 @@ static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
 	set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
 
 	if (smp_processor_id() != pol->cpu) {
-		printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
+		printk(KERN_ERR PFX "limiting to cpu %u failed\n", pol->cpu);
 		goto err_out;
 	}
 
@@ -1162,10 +1169,9 @@ static void __exit powernowk8_exit(void)
 	cpufreq_unregister_driver(&cpufreq_amd64_driver);
 }
 
-MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com> and Mark Langsdorf <mark.langsdorf@amd.com.");
+MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com> and Mark Langsdorf <mark.langsdorf@amd.com>");
 MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
 MODULE_LICENSE("GPL");
 
 late_initcall(powernowk8_init);
 module_exit(powernowk8_exit);
-

arch/i386/kernel/cpu/cpufreq/powernow-k8.h

@@ -42,7 +42,7 @@ struct powernow_k8_data {
 #define CPUID_XFAM			0x0ff00000	/* extended family */
 #define CPUID_XFAM_K8			0
 #define CPUID_XMOD			0x000f0000	/* extended model */
-#define CPUID_XMOD_REV_F		0x00040000
+#define CPUID_XMOD_REV_G		0x00060000
 #define CPUID_USE_XFAM_XMOD		0x00000f00
 #define CPUID_GET_MAX_CAPABILITIES	0x80000000
 #define CPUID_FREQ_VOLT_CAPABILITIES	0x80000007
@@ -86,13 +86,14 @@ struct powernow_k8_data {
  *   low fid table
  * - lowest entry in the high fid table must be a <= 200MHz + 2 * the entry
  *   in the low fid table
- * - the parts can only step at 200 MHz intervals, so 1.9 GHz is never valid
+ * - the parts can only step at <= 200 MHz intervals, odd fid values are
+ *   supported in revision G and later revisions.
  * - lowest frequency must be >= interprocessor hypertransport link speed
  *   (only applies to MP systems obviously)
  */
 
 /* fids (frequency identifiers) are arranged in 2 tables - lo and hi */
-#define LO_FID_TABLE_TOP     6	/* fid values marking the boundary    */
+#define LO_FID_TABLE_TOP     7	/* fid values marking the boundary    */
 #define HI_FID_TABLE_BOTTOM  8	/* between the low and high tables    */
 
 #define LO_VCOFREQ_TABLE_TOP    1400	/* corresponding vco frequency values */
@@ -106,7 +107,7 @@ struct powernow_k8_data {
 #define MIN_FREQ 800	/* Min and max freqs, per spec */
 #define MAX_FREQ 5000
 
-#define INVALID_FID_MASK 0xffffffc1  /* not a valid fid if these bits are set */
+#define INVALID_FID_MASK 0xffffffc0  /* not a valid fid if these bits are set */
 #define INVALID_VID_MASK 0xffffffc0  /* not a valid vid if these bits are set */
 
 #define VID_OFF 0x3f

arch/i386/kernel/cpu/cpufreq/speedstep-ich.c

@@ -40,6 +40,7 @@ static struct pci_dev *speedstep_chipset_dev;
  */
 static unsigned int speedstep_processor = 0;
 
+static u32 pmbase;
 
 /*
  *   There are only two frequency states for each processor. Values
@@ -56,34 +57,47 @@ static struct cpufreq_frequency_table speedstep_freqs[] = {
 
 
 /**
- * speedstep_set_state - set the SpeedStep state
- * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
+ * speedstep_find_register - read the PMBASE address
  *
- *   Tries to change the SpeedStep state.
+ * Returns: -ENODEV if no register could be found
  */
-static void speedstep_set_state (unsigned int state)
+static int speedstep_find_register (void)
 {
-	u32 pmbase;
-	u8 pm2_blk;
-	u8 value;
-	unsigned long flags;
-
-	if (!speedstep_chipset_dev || (state > 0x1))
-		return;
+	if (!speedstep_chipset_dev)
+		return -ENODEV;
 
 	/* get PMBASE */
 	pci_read_config_dword(speedstep_chipset_dev, 0x40, &pmbase);
 	if (!(pmbase & 0x01)) {
 		printk(KERN_ERR "speedstep-ich: could not find speedstep register\n");
-		return;
+		return -ENODEV;
 	}
 
 	pmbase &= 0xFFFFFFFE;
 	if (!pmbase) {
 		printk(KERN_ERR "speedstep-ich: could not find speedstep register\n");
-		return;
+		return -ENODEV;
 	}
 
+	dprintk("pmbase is 0x%x\n", pmbase);
+	return 0;
+}
+
+/**
+ * speedstep_set_state - set the SpeedStep state
+ * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
+ *
+ *   Tries to change the SpeedStep state.
+ */
+static void speedstep_set_state (unsigned int state)
+{
+	u8 pm2_blk;
+	u8 value;
+	unsigned long flags;
+
+	if (state > 0x1)
+		return;
+
 	/* Disable IRQs */
 	local_irq_save(flags);
 
@@ -315,10 +329,11 @@ static int speedstep_cpu_init(struct cpufreq_policy *policy)
 	cpus_allowed = current->cpus_allowed;
 	set_cpus_allowed(current, policy->cpus);
 
-	/* detect low and high frequency */
+	/* detect low and high frequency and transition latency */
 	result = speedstep_get_freqs(speedstep_processor,
 				     &speedstep_freqs[SPEEDSTEP_LOW].frequency,
 				     &speedstep_freqs[SPEEDSTEP_HIGH].frequency,
+				     &policy->cpuinfo.transition_latency,
 				     &speedstep_set_state);
 	set_cpus_allowed(current, cpus_allowed);
 	if (result)
@@ -335,7 +350,6 @@ static int speedstep_cpu_init(struct cpufreq_policy *policy)
 
 	/* cpuinfo and default policy values */
 	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 	policy->cur = speed;
 
 	result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs);
@@ -400,6 +414,9 @@ static int __init speedstep_init(void)
 		return -EINVAL;
 	}
 
+	if (speedstep_find_register())
+		return -ENODEV;
+
 	return cpufreq_register_driver(&speedstep_driver);
 }
 

arch/i386/kernel/cpu/cpufreq/speedstep-lib.c

@@ -320,11 +320,13 @@ EXPORT_SYMBOL_GPL(speedstep_detect_processor);
 unsigned int speedstep_get_freqs(unsigned int processor,
 				  unsigned int *low_speed,
 				  unsigned int *high_speed,
+				  unsigned int *transition_latency,
 				  void (*set_state) (unsigned int state))
 {
 	unsigned int prev_speed;
 	unsigned int ret = 0;
 	unsigned long flags;
+	struct timeval tv1, tv2;
 
 	if ((!processor) || (!low_speed) || (!high_speed) || (!set_state))
 		return -EINVAL;
@@ -337,7 +339,7 @@ unsigned int speedstep_get_freqs(unsigned int processor,
 		return -EIO;
 
 	dprintk("previous speed is %u\n", prev_speed);
-	
+
 	local_irq_save(flags);
 
 	/* switch to low state */
@@ -350,8 +352,17 @@ unsigned int speedstep_get_freqs(unsigned int processor,
 
 	dprintk("low speed is %u\n", *low_speed);
 
+	/* start latency measurement */
+	if (transition_latency)
+		do_gettimeofday(&tv1);
+
 	/* switch to high state */
 	set_state(SPEEDSTEP_HIGH);
+
+	/* end latency measurement */
+	if (transition_latency)
+		do_gettimeofday(&tv2);
+
 	*high_speed = speedstep_get_processor_frequency(processor);
 	if (!*high_speed) {
 		ret = -EIO;
@@ -369,6 +380,25 @@ unsigned int speedstep_get_freqs(unsigned int processor,
 	if (*high_speed != prev_speed)
 		set_state(SPEEDSTEP_LOW);
 
+	if (transition_latency) {
+		*transition_latency = (tv2.tv_sec - tv1.tv_sec) * USEC_PER_SEC +
+			tv2.tv_usec - tv1.tv_usec;
+		dprintk("transition latency is %u uSec\n", *transition_latency);
+
+		/* convert uSec to nSec and add 20% for safety reasons */
+		*transition_latency *= 1200;
+
+		/* check if the latency measurement is too high or too low
+		 * and set it to a safe value (500uSec) in that case
+		 */
+		if (*transition_latency > 10000000 || *transition_latency < 50000) {
+			printk (KERN_WARNING "speedstep: frequency transition measured seems out of "
+					"range (%u nSec), falling back to a safe one of %u nSec.\n",
+					*transition_latency, 500000);
+			*transition_latency = 500000;
+		}
+	}
+
  out:
 	local_irq_restore(flags);
 	return (ret);

arch/i386/kernel/cpu/cpufreq/speedstep-lib.h

@@ -44,4 +44,5 @@ extern unsigned int speedstep_get_processor_frequency(unsigned int processor);
 extern unsigned int speedstep_get_freqs(unsigned int processor,
 	  unsigned int *low_speed,
 	  unsigned int *high_speed,
+	  unsigned int *transition_latency,
 	  void (*set_state) (unsigned int state));

arch/i386/kernel/cpu/cpufreq/speedstep-smi.c

@@ -269,6 +269,7 @@ static int speedstep_cpu_init(struct cpufreq_policy *policy)
 		result = speedstep_get_freqs(speedstep_processor,
 				&speedstep_freqs[SPEEDSTEP_LOW].frequency,
 				&speedstep_freqs[SPEEDSTEP_HIGH].frequency,
+				NULL,
 				&speedstep_set_state);
 
 		if (result) {

arch/i386/kernel/cpu/proc.c

@@ -3,6 +3,7 @@
 #include <linux/string.h>
 #include <asm/semaphore.h>
 #include <linux/seq_file.h>
+#include <linux/cpufreq.h>
 
 /*
  *	Get CPU information for use by the procfs.
@@ -86,8 +87,11 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		seq_printf(m, "stepping\t: unknown\n");
 
 	if ( cpu_has(c, X86_FEATURE_TSC) ) {
+		unsigned int freq = cpufreq_quick_get(n);
+		if (!freq)
+			freq = cpu_khz;
 		seq_printf(m, "cpu MHz\t\t: %u.%03u\n",
-			cpu_khz / 1000, (cpu_khz % 1000));
+			freq / 1000, (freq % 1000));
 	}
 
 	/* Cache size */

arch/ia64/kernel/setup.c

@@ -43,6 +43,7 @@
 #include <linux/initrd.h>
 #include <linux/platform.h>
 #include <linux/pm.h>
+#include <linux/cpufreq.h>
 
 #include <asm/ia32.h>
 #include <asm/machvec.h>
@@ -517,6 +518,7 @@ show_cpuinfo (struct seq_file *m, void *v)
 	char family[32], features[128], *cp, sep;
 	struct cpuinfo_ia64 *c = v;
 	unsigned long mask;
+	unsigned int proc_freq;
 	int i;
 
 	mask = c->features;
@@ -549,6 +551,10 @@ show_cpuinfo (struct seq_file *m, void *v)
 		sprintf(cp, " 0x%lx", mask);
 	}
 
+	proc_freq = cpufreq_quick_get(cpunum);
+	if (!proc_freq)
+		proc_freq = c->proc_freq / 1000;
+
 	seq_printf(m,
 		   "processor  : %d\n"
 		   "vendor     : %s\n"
@@ -565,7 +571,7 @@ show_cpuinfo (struct seq_file *m, void *v)
 		   "BogoMIPS   : %lu.%02lu\n",
 		   cpunum, c->vendor, family, c->model, c->revision, c->archrev,
 		   features, c->ppn, c->number,
-		   c->proc_freq / 1000000, c->proc_freq % 1000000,
+		   proc_freq / 1000, proc_freq % 1000,
 		   c->itc_freq / 1000000, c->itc_freq % 1000000,
 		   lpj*HZ/500000, (lpj*HZ/5000) % 100);
 #ifdef CONFIG_SMP

arch/x86_64/kernel/setup.c

@@ -42,6 +42,7 @@
 #include <linux/edd.h>
 #include <linux/mmzone.h>
 #include <linux/kexec.h>
+#include <linux/cpufreq.h>
 
 #include <asm/mtrr.h>
 #include <asm/uaccess.h>
@@ -1256,8 +1257,11 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		seq_printf(m, "stepping\t: unknown\n");
 	
 	if (cpu_has(c,X86_FEATURE_TSC)) {
+		unsigned int freq = cpufreq_quick_get((unsigned)(c-cpu_data));
+		if (!freq)
+			freq = cpu_khz;
 		seq_printf(m, "cpu MHz\t\t: %u.%03u\n",
-			     cpu_khz / 1000, (cpu_khz % 1000));
+			     freq / 1000, (freq % 1000));
 	}
 
 	/* Cache size */

drivers/cpufreq/cpufreq.c

@@ -822,6 +822,30 @@ static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, unsigne
 }
 
 
+/** 
+ * cpufreq_quick_get - get the CPU frequency (in kHz) frpm policy->cur
+ * @cpu: CPU number
+ *
+ * This is the last known freq, without actually getting it from the driver.
+ * Return value will be same as what is shown in scaling_cur_freq in sysfs.
+ */
+unsigned int cpufreq_quick_get(unsigned int cpu)
+{
+	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+	unsigned int ret = 0;
+
+	if (policy) {
+		down(&policy->lock);
+		ret = policy->cur;
+		up(&policy->lock);
+		cpufreq_cpu_put(policy);
+	}
+
+	return (ret);
+}
+EXPORT_SYMBOL(cpufreq_quick_get);
+
+
 /** 
  * cpufreq_get - get the current CPU frequency (in kHz)
  * @cpu: CPU number

drivers/cpufreq/cpufreq_conservative.c

@@ -93,7 +93,7 @@ static inline unsigned int get_cpu_idle_time(unsigned int cpu)
 {
 	return	kstat_cpu(cpu).cpustat.idle +
 		kstat_cpu(cpu).cpustat.iowait +
-		( !dbs_tuners_ins.ignore_nice ? 
+		( dbs_tuners_ins.ignore_nice ?
 		  kstat_cpu(cpu).cpustat.nice :
 		  0);
 }
@@ -127,7 +127,7 @@ show_one(sampling_rate, sampling_rate);
 show_one(sampling_down_factor, sampling_down_factor);
 show_one(up_threshold, up_threshold);
 show_one(down_threshold, down_threshold);
-show_one(ignore_nice, ignore_nice);
+show_one(ignore_nice_load, ignore_nice);
 show_one(freq_step, freq_step);
 
 static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused, 
@@ -207,7 +207,7 @@ static ssize_t store_down_threshold(struct cpufreq_policy *unused,
 	return count;
 }
 
-static ssize_t store_ignore_nice(struct cpufreq_policy *policy,
+static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
 		const char *buf, size_t count)
 {
 	unsigned int input;
@@ -272,7 +272,7 @@ define_one_rw(sampling_rate);
 define_one_rw(sampling_down_factor);
 define_one_rw(up_threshold);
 define_one_rw(down_threshold);
-define_one_rw(ignore_nice);
+define_one_rw(ignore_nice_load);
 define_one_rw(freq_step);
 
 static struct attribute * dbs_attributes[] = {
@@ -282,7 +282,7 @@ static struct attribute * dbs_attributes[] = {
 	&sampling_down_factor.attr,
 	&up_threshold.attr,
 	&down_threshold.attr,
-	&ignore_nice.attr,
+	&ignore_nice_load.attr,
 	&freq_step.attr,
 	NULL
 };

drivers/cpufreq/cpufreq_ondemand.c

@@ -89,7 +89,7 @@ static inline unsigned int get_cpu_idle_time(unsigned int cpu)
 {
 	return	kstat_cpu(cpu).cpustat.idle +
 		kstat_cpu(cpu).cpustat.iowait +
-		( !dbs_tuners_ins.ignore_nice ? 
+		( dbs_tuners_ins.ignore_nice ?
 		  kstat_cpu(cpu).cpustat.nice :
 		  0);
 }
@@ -122,7 +122,7 @@ static ssize_t show_##file_name						\
 show_one(sampling_rate, sampling_rate);
 show_one(sampling_down_factor, sampling_down_factor);
 show_one(up_threshold, up_threshold);
-show_one(ignore_nice, ignore_nice);
+show_one(ignore_nice_load, ignore_nice);
 
 static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused, 
 		const char *buf, size_t count)
@@ -182,7 +182,7 @@ static ssize_t store_up_threshold(struct cpufreq_policy *unused,
 	return count;
 }
 
-static ssize_t store_ignore_nice(struct cpufreq_policy *policy,
+static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
 		const char *buf, size_t count)
 {
 	unsigned int input;
@@ -223,7 +223,7 @@ __ATTR(_name, 0644, show_##_name, store_##_name)
 define_one_rw(sampling_rate);
 define_one_rw(sampling_down_factor);
 define_one_rw(up_threshold);
-define_one_rw(ignore_nice);
+define_one_rw(ignore_nice_load);
 
 static struct attribute * dbs_attributes[] = {
 	&sampling_rate_max.attr,
@@ -231,7 +231,7 @@ static struct attribute * dbs_attributes[] = {
 	&sampling_rate.attr,
 	&sampling_down_factor.attr,
 	&up_threshold.attr,
-	&ignore_nice.attr,
+	&ignore_nice_load.attr,
 	NULL
 };
 

include/linux/cpufreq.h

@@ -256,6 +256,16 @@ int cpufreq_update_policy(unsigned int cpu);
 /* query the current CPU frequency (in kHz). If zero, cpufreq couldn't detect it */
 unsigned int cpufreq_get(unsigned int cpu);
 
+/* query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it */
+#ifdef CONFIG_CPU_FREQ
+unsigned int cpufreq_quick_get(unsigned int cpu);
+#else
+static inline unsigned int cpufreq_quick_get(unsigned int cpu)
+{
+	return 0;
+}
+#endif
+
 
 /*********************************************************************
  *                       CPUFREQ DEFAULT GOVERNOR                    *