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authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-17 12:51:50 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-17 12:51:50 -0400
commitc30938d59e7468259855da91a885b19e8044b5f4 (patch)
tree15fa3b7c4696947d43702273291398a91232f644 /drivers/cpufreq/cpufreq_conservative.c
parentaa2638a210ab0d7c6702cd54315365785fce326c (diff)
parent8e7c25971b1590776a90b249de3d859dd45e7414 (diff)
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: [CPUFREQ] cpumask: new cpumask operators for arch/x86/kernel/cpu/cpufreq/powernow-k8.c [CPUFREQ] cpumask: avoid playing with cpus_allowed in powernow-k8.c [CPUFREQ] cpumask: avoid cpumask games in arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c [CPUFREQ] cpumask: avoid playing with cpus_allowed in speedstep-ich.c [CPUFREQ] powernow-k8: get drv data for correct CPU [CPUFREQ] powernow-k8: read P-state from HW [CPUFREQ] reduce scope of ACPI_PSS_BIOS_BUG_MSG[] [CPUFREQ] Clean up convoluted code in arch/x86/kernel/tsc.c:time_cpufreq_notifier() [CPUFREQ] minor correction to cpu-freq documentation [CPUFREQ] powernow-k8.c: mess cleanup [CPUFREQ] Only set sampling_rate_max deprecated, sampling_rate_min is useful [CPUFREQ] powernow-k8: Set transition latency to 1 if ACPI tables export 0 [CPUFREQ] ondemand: Uncouple minimal sampling rate from HZ in NO_HZ case
Diffstat (limited to 'drivers/cpufreq/cpufreq_conservative.c')
-rw-r--r--drivers/cpufreq/cpufreq_conservative.c61
1 files changed, 20 insertions, 41 deletions
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 7a74d175287b..7fc58af748b4 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -42,27 +42,12 @@
42 * this governor will not work. 42 * this governor will not work.
43 * All times here are in uS. 43 * All times here are in uS.
44 */ 44 */
45static unsigned int def_sampling_rate;
46#define MIN_SAMPLING_RATE_RATIO (2) 45#define MIN_SAMPLING_RATE_RATIO (2)
47/* for correct statistics, we need at least 10 ticks between each measure */
48#define MIN_STAT_SAMPLING_RATE \
49 (MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10))
50#define MIN_SAMPLING_RATE \
51 (def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
52/* Above MIN_SAMPLING_RATE will vanish with its sysfs file soon
53 * Define the minimal settable sampling rate to the greater of:
54 * - "HW transition latency" * 100 (same as default sampling / 10)
55 * - MIN_STAT_SAMPLING_RATE
56 * To avoid that userspace shoots itself.
57*/
58static unsigned int minimum_sampling_rate(void)
59{
60 return max(def_sampling_rate / 10, MIN_STAT_SAMPLING_RATE);
61}
62 46
63/* This will also vanish soon with removing sampling_rate_max */ 47static unsigned int min_sampling_rate;
64#define MAX_SAMPLING_RATE (500 * def_sampling_rate) 48
65#define LATENCY_MULTIPLIER (1000) 49#define LATENCY_MULTIPLIER (1000)
50#define MIN_LATENCY_MULTIPLIER (100)
66#define DEF_SAMPLING_DOWN_FACTOR (1) 51#define DEF_SAMPLING_DOWN_FACTOR (1)
67#define MAX_SAMPLING_DOWN_FACTOR (10) 52#define MAX_SAMPLING_DOWN_FACTOR (10)
68#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) 53#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
@@ -182,27 +167,14 @@ static struct notifier_block dbs_cpufreq_notifier_block = {
182/************************** sysfs interface ************************/ 167/************************** sysfs interface ************************/
183static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf) 168static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf)
184{ 169{
185 static int print_once; 170 printk_once(KERN_INFO "CPUFREQ: conservative sampling_rate_max "
186 171 "sysfs file is deprecated - used by: %s\n", current->comm);
187 if (!print_once) { 172 return sprintf(buf, "%u\n", -1U);
188 printk(KERN_INFO "CPUFREQ: conservative sampling_rate_max "
189 "sysfs file is deprecated - used by: %s\n",
190 current->comm);
191 print_once = 1;
192 }
193 return sprintf(buf, "%u\n", MAX_SAMPLING_RATE);
194} 173}
195 174
196static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf) 175static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf)
197{ 176{
198 static int print_once; 177 return sprintf(buf, "%u\n", min_sampling_rate);
199
200 if (!print_once) {
201 printk(KERN_INFO "CPUFREQ: conservative sampling_rate_max "
202 "sysfs file is deprecated - used by: %s\n", current->comm);
203 print_once = 1;
204 }
205 return sprintf(buf, "%u\n", MIN_SAMPLING_RATE);
206} 178}
207 179
208#define define_one_ro(_name) \ 180#define define_one_ro(_name) \
@@ -254,7 +226,7 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
254 return -EINVAL; 226 return -EINVAL;
255 227
256 mutex_lock(&dbs_mutex); 228 mutex_lock(&dbs_mutex);
257 dbs_tuners_ins.sampling_rate = max(input, minimum_sampling_rate()); 229 dbs_tuners_ins.sampling_rate = max(input, min_sampling_rate);
258 mutex_unlock(&dbs_mutex); 230 mutex_unlock(&dbs_mutex);
259 231
260 return count; 232 return count;
@@ -601,11 +573,18 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
601 if (latency == 0) 573 if (latency == 0)
602 latency = 1; 574 latency = 1;
603 575
604 def_sampling_rate = 576 /*
605 max(latency * LATENCY_MULTIPLIER, 577 * conservative does not implement micro like ondemand
606 MIN_STAT_SAMPLING_RATE); 578 * governor, thus we are bound to jiffes/HZ
607 579 */
608 dbs_tuners_ins.sampling_rate = def_sampling_rate; 580 min_sampling_rate =
581 MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10);
582 /* Bring kernel and HW constraints together */
583 min_sampling_rate = max(min_sampling_rate,
584 MIN_LATENCY_MULTIPLIER * latency);
585 dbs_tuners_ins.sampling_rate =
586 max(min_sampling_rate,
587 latency * LATENCY_MULTIPLIER);
609 588
610 cpufreq_register_notifier( 589 cpufreq_register_notifier(
611 &dbs_cpufreq_notifier_block, 590 &dbs_cpufreq_notifier_block,