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-rw-r--r--arch/i386/Kconfig2
-rw-r--r--arch/x86_64/Kconfig2
-rw-r--r--drivers/Makefile1
-rw-r--r--drivers/acpi/osl.c8
-rw-r--r--drivers/acpi/processor_core.c22
-rw-r--r--drivers/acpi/processor_idle.c482
-rw-r--r--drivers/cpuidle/Kconfig20
-rw-r--r--drivers/cpuidle/Makefile5
-rw-r--r--drivers/cpuidle/cpuidle.c295
-rw-r--r--drivers/cpuidle/cpuidle.h33
-rw-r--r--drivers/cpuidle/driver.c56
-rw-r--r--drivers/cpuidle/governor.c141
-rw-r--r--drivers/cpuidle/governors/Makefile6
-rw-r--r--drivers/cpuidle/governors/ladder.c166
-rw-r--r--drivers/cpuidle/governors/menu.c137
-rw-r--r--drivers/cpuidle/sysfs.c361
-rw-r--r--drivers/net/wireless/ipw2100.c29
-rw-r--r--drivers/net/wireless/ipw2100.h2
-rw-r--r--include/acpi/processor.h5
-rw-r--r--include/linux/acpi.h26
-rw-r--r--include/linux/cpuidle.h180
-rw-r--r--include/linux/tick.h9
-rw-r--r--kernel/time/tick-sched.c16
23 files changed, 1895 insertions, 109 deletions
diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index 97b64d7d6bf6..3328e0ab5428 100644
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -1069,6 +1069,8 @@ endif # APM
1069 1069
1070source "arch/i386/kernel/cpu/cpufreq/Kconfig" 1070source "arch/i386/kernel/cpu/cpufreq/Kconfig"
1071 1071
1072source "drivers/cpuidle/Kconfig"
1073
1072endmenu 1074endmenu
1073 1075
1074menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)" 1076menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index b4d9089a6a06..e8dbb37a29cf 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -706,6 +706,8 @@ source "drivers/acpi/Kconfig"
706 706
707source "arch/x86_64/kernel/cpufreq/Kconfig" 707source "arch/x86_64/kernel/cpufreq/Kconfig"
708 708
709source "drivers/cpuidle/Kconfig"
710
709endmenu 711endmenu
710 712
711menu "Bus options (PCI etc.)" 713menu "Bus options (PCI etc.)"
diff --git a/drivers/Makefile b/drivers/Makefile
index f0878b2ec55e..10a9c52c9100 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -76,6 +76,7 @@ obj-$(CONFIG_MCA) += mca/
76obj-$(CONFIG_EISA) += eisa/ 76obj-$(CONFIG_EISA) += eisa/
77obj-$(CONFIG_LGUEST_GUEST) += lguest/ 77obj-$(CONFIG_LGUEST_GUEST) += lguest/
78obj-$(CONFIG_CPU_FREQ) += cpufreq/ 78obj-$(CONFIG_CPU_FREQ) += cpufreq/
79obj-$(CONFIG_CPU_IDLE) += cpuidle/
79obj-$(CONFIG_MMC) += mmc/ 80obj-$(CONFIG_MMC) += mmc/
80obj-$(CONFIG_NEW_LEDS) += leds/ 81obj-$(CONFIG_NEW_LEDS) += leds/
81obj-$(CONFIG_INFINIBAND) += infiniband/ 82obj-$(CONFIG_INFINIBAND) += infiniband/
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 12c09fafce9a..5d14d4f10b12 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -1043,14 +1043,6 @@ static int __init acpi_wake_gpes_always_on_setup(char *str)
1043__setup("acpi_wake_gpes_always_on", acpi_wake_gpes_always_on_setup); 1043__setup("acpi_wake_gpes_always_on", acpi_wake_gpes_always_on_setup);
1044 1044
1045/* 1045/*
1046 * max_cstate is defined in the base kernel so modules can
1047 * change it w/o depending on the state of the processor module.
1048 */
1049unsigned int max_cstate = ACPI_PROCESSOR_MAX_POWER;
1050
1051EXPORT_SYMBOL(max_cstate);
1052
1053/*
1054 * Acquire a spinlock. 1046 * Acquire a spinlock.
1055 * 1047 *
1056 * handle is a pointer to the spinlock_t. 1048 * handle is a pointer to the spinlock_t.
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 9f11dc296cdd..a7351084f2f8 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -44,6 +44,7 @@
44#include <linux/seq_file.h> 44#include <linux/seq_file.h>
45#include <linux/dmi.h> 45#include <linux/dmi.h>
46#include <linux/moduleparam.h> 46#include <linux/moduleparam.h>
47#include <linux/cpuidle.h>
47 48
48#include <asm/io.h> 49#include <asm/io.h>
49#include <asm/system.h> 50#include <asm/system.h>
@@ -1049,11 +1050,13 @@ static int __init acpi_processor_init(void)
1049 return -ENOMEM; 1050 return -ENOMEM;
1050 acpi_processor_dir->owner = THIS_MODULE; 1051 acpi_processor_dir->owner = THIS_MODULE;
1051 1052
1053 result = cpuidle_register_driver(&acpi_idle_driver);
1054 if (result < 0)
1055 goto out_proc;
1056
1052 result = acpi_bus_register_driver(&acpi_processor_driver); 1057 result = acpi_bus_register_driver(&acpi_processor_driver);
1053 if (result < 0) { 1058 if (result < 0)
1054 remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir); 1059 goto out_cpuidle;
1055 return result;
1056 }
1057 1060
1058 acpi_processor_install_hotplug_notify(); 1061 acpi_processor_install_hotplug_notify();
1059 1062
@@ -1062,11 +1065,18 @@ static int __init acpi_processor_init(void)
1062 acpi_processor_ppc_init(); 1065 acpi_processor_ppc_init();
1063 1066
1064 return 0; 1067 return 0;
1068
1069out_cpuidle:
1070 cpuidle_unregister_driver(&acpi_idle_driver);
1071
1072out_proc:
1073 remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
1074
1075 return result;
1065} 1076}
1066 1077
1067static void __exit acpi_processor_exit(void) 1078static void __exit acpi_processor_exit(void)
1068{ 1079{
1069
1070 acpi_processor_ppc_exit(); 1080 acpi_processor_ppc_exit();
1071 1081
1072 acpi_thermal_cpufreq_exit(); 1082 acpi_thermal_cpufreq_exit();
@@ -1075,6 +1085,8 @@ static void __exit acpi_processor_exit(void)
1075 1085
1076 acpi_bus_unregister_driver(&acpi_processor_driver); 1086 acpi_bus_unregister_driver(&acpi_processor_driver);
1077 1087
1088 cpuidle_unregister_driver(&acpi_idle_driver);
1089
1078 remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir); 1090 remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
1079 1091
1080 return; 1092 return;
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index f18261368e76..99da6a790857 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -40,6 +40,7 @@
40#include <linux/sched.h> /* need_resched() */ 40#include <linux/sched.h> /* need_resched() */
41#include <linux/latency.h> 41#include <linux/latency.h>
42#include <linux/clockchips.h> 42#include <linux/clockchips.h>
43#include <linux/cpuidle.h>
43 44
44/* 45/*
45 * Include the apic definitions for x86 to have the APIC timer related defines 46 * Include the apic definitions for x86 to have the APIC timer related defines
@@ -64,14 +65,22 @@ ACPI_MODULE_NAME("processor_idle");
64#define ACPI_PROCESSOR_FILE_POWER "power" 65#define ACPI_PROCESSOR_FILE_POWER "power"
65#define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000) 66#define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000)
66#define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY) 67#define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY)
68#ifndef CONFIG_CPU_IDLE
67#define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ 69#define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */
68#define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */ 70#define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */
69static void (*pm_idle_save) (void) __read_mostly; 71static void (*pm_idle_save) (void) __read_mostly;
70module_param(max_cstate, uint, 0644); 72#else
73#define C2_OVERHEAD 1 /* 1us */
74#define C3_OVERHEAD 1 /* 1us */
75#endif
76#define PM_TIMER_TICKS_TO_US(p) (((p) * 1000)/(PM_TIMER_FREQUENCY/1000))
71 77
78static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
79module_param(max_cstate, uint, 0000);
72static unsigned int nocst __read_mostly; 80static unsigned int nocst __read_mostly;
73module_param(nocst, uint, 0000); 81module_param(nocst, uint, 0000);
74 82
83#ifndef CONFIG_CPU_IDLE
75/* 84/*
76 * bm_history -- bit-mask with a bit per jiffy of bus-master activity 85 * bm_history -- bit-mask with a bit per jiffy of bus-master activity
77 * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms 86 * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms
@@ -82,9 +91,10 @@ module_param(nocst, uint, 0000);
82static unsigned int bm_history __read_mostly = 91static unsigned int bm_history __read_mostly =
83 (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1)); 92 (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1));
84module_param(bm_history, uint, 0644); 93module_param(bm_history, uint, 0644);
85/* -------------------------------------------------------------------------- 94
86 Power Management 95static int acpi_processor_set_power_policy(struct acpi_processor *pr);
87 -------------------------------------------------------------------------- */ 96
97#endif
88 98
89/* 99/*
90 * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. 100 * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
@@ -177,6 +187,18 @@ static inline u32 ticks_elapsed(u32 t1, u32 t2)
177 return ((0xFFFFFFFF - t1) + t2); 187 return ((0xFFFFFFFF - t1) + t2);
178} 188}
179 189
190static inline u32 ticks_elapsed_in_us(u32 t1, u32 t2)
191{
192 if (t2 >= t1)
193 return PM_TIMER_TICKS_TO_US(t2 - t1);
194 else if (!(acpi_gbl_FADT.flags & ACPI_FADT_32BIT_TIMER))
195 return PM_TIMER_TICKS_TO_US(((0x00FFFFFF - t1) + t2) & 0x00FFFFFF);
196 else
197 return PM_TIMER_TICKS_TO_US((0xFFFFFFFF - t1) + t2);
198}
199
200#ifndef CONFIG_CPU_IDLE
201
180static void 202static void
181acpi_processor_power_activate(struct acpi_processor *pr, 203acpi_processor_power_activate(struct acpi_processor *pr,
182 struct acpi_processor_cx *new) 204 struct acpi_processor_cx *new)
@@ -248,6 +270,7 @@ static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
248 unused = inl(acpi_gbl_FADT.xpm_timer_block.address); 270 unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
249 } 271 }
250} 272}
273#endif /* !CONFIG_CPU_IDLE */
251 274
252#ifdef ARCH_APICTIMER_STOPS_ON_C3 275#ifdef ARCH_APICTIMER_STOPS_ON_C3
253 276
@@ -342,6 +365,7 @@ int acpi_processor_resume(struct acpi_device * device)
342 return 0; 365 return 0;
343} 366}
344 367
368#ifndef CONFIG_CPU_IDLE
345static void acpi_processor_idle(void) 369static void acpi_processor_idle(void)
346{ 370{
347 struct acpi_processor *pr = NULL; 371 struct acpi_processor *pr = NULL;
@@ -439,7 +463,7 @@ static void acpi_processor_idle(void)
439 * an SMP system. We do it here instead of doing it at _CST/P_LVL 463 * an SMP system. We do it here instead of doing it at _CST/P_LVL
440 * detection phase, to work cleanly with logical CPU hotplug. 464 * detection phase, to work cleanly with logical CPU hotplug.
441 */ 465 */
442 if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && 466 if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
443 !pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 467 !pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
444 cx = &pr->power.states[ACPI_STATE_C1]; 468 cx = &pr->power.states[ACPI_STATE_C1];
445#endif 469#endif
@@ -739,6 +763,7 @@ static int acpi_processor_set_power_policy(struct acpi_processor *pr)
739 763
740 return 0; 764 return 0;
741} 765}
766#endif /* !CONFIG_CPU_IDLE */
742 767
743static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) 768static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
744{ 769{
@@ -756,7 +781,7 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
756#ifndef CONFIG_HOTPLUG_CPU 781#ifndef CONFIG_HOTPLUG_CPU
757 /* 782 /*
758 * Check for P_LVL2_UP flag before entering C2 and above on 783 * Check for P_LVL2_UP flag before entering C2 and above on
759 * an SMP system. 784 * an SMP system.
760 */ 785 */
761 if ((num_online_cpus() > 1) && 786 if ((num_online_cpus() > 1) &&
762 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 787 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
@@ -957,7 +982,12 @@ static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx)
957 * Normalize the C2 latency to expidite policy 982 * Normalize the C2 latency to expidite policy
958 */ 983 */
959 cx->valid = 1; 984 cx->valid = 1;
985
986#ifndef CONFIG_CPU_IDLE
960 cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); 987 cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency);
988#else
989 cx->latency_ticks = cx->latency;
990#endif
961 991
962 return; 992 return;
963} 993}
@@ -1037,7 +1067,12 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
1037 * use this in our C3 policy 1067 * use this in our C3 policy
1038 */ 1068 */
1039 cx->valid = 1; 1069 cx->valid = 1;
1070
1071#ifndef CONFIG_CPU_IDLE
1040 cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); 1072 cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency);
1073#else
1074 cx->latency_ticks = cx->latency;
1075#endif
1041 1076
1042 return; 1077 return;
1043} 1078}
@@ -1102,6 +1137,7 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
1102 1137
1103 pr->power.count = acpi_processor_power_verify(pr); 1138 pr->power.count = acpi_processor_power_verify(pr);
1104 1139
1140#ifndef CONFIG_CPU_IDLE
1105 /* 1141 /*
1106 * Set Default Policy 1142 * Set Default Policy
1107 * ------------------ 1143 * ------------------
@@ -1113,6 +1149,7 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
1113 result = acpi_processor_set_power_policy(pr); 1149 result = acpi_processor_set_power_policy(pr);
1114 if (result) 1150 if (result)
1115 return result; 1151 return result;
1152#endif
1116 1153
1117 /* 1154 /*
1118 * if one state of type C2 or C3 is available, mark this 1155 * if one state of type C2 or C3 is available, mark this
@@ -1129,35 +1166,6 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
1129 return 0; 1166 return 0;
1130} 1167}
1131 1168
1132int acpi_processor_cst_has_changed(struct acpi_processor *pr)
1133{
1134 int result = 0;
1135
1136
1137 if (!pr)
1138 return -EINVAL;
1139
1140 if (nocst) {
1141 return -ENODEV;
1142 }
1143
1144 if (!pr->flags.power_setup_done)
1145 return -ENODEV;
1146
1147 /* Fall back to the default idle loop */
1148 pm_idle = pm_idle_save;
1149 synchronize_sched(); /* Relies on interrupts forcing exit from idle. */
1150
1151 pr->flags.power = 0;
1152 result = acpi_processor_get_power_info(pr);
1153 if ((pr->flags.power == 1) && (pr->flags.power_setup_done))
1154 pm_idle = acpi_processor_idle;
1155
1156 return result;
1157}
1158
1159/* proc interface */
1160
1161static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) 1169static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset)
1162{ 1170{
1163 struct acpi_processor *pr = seq->private; 1171 struct acpi_processor *pr = seq->private;
@@ -1239,6 +1247,35 @@ static const struct file_operations acpi_processor_power_fops = {
1239 .release = single_release, 1247 .release = single_release,
1240}; 1248};
1241 1249
1250#ifndef CONFIG_CPU_IDLE
1251
1252int acpi_processor_cst_has_changed(struct acpi_processor *pr)
1253{
1254 int result = 0;
1255
1256
1257 if (!pr)
1258 return -EINVAL;
1259
1260 if (nocst) {
1261 return -ENODEV;
1262 }
1263
1264 if (!pr->flags.power_setup_done)
1265 return -ENODEV;
1266
1267 /* Fall back to the default idle loop */
1268 pm_idle = pm_idle_save;
1269 synchronize_sched(); /* Relies on interrupts forcing exit from idle. */
1270
1271 pr->flags.power = 0;
1272 result = acpi_processor_get_power_info(pr);
1273 if ((pr->flags.power == 1) && (pr->flags.power_setup_done))
1274 pm_idle = acpi_processor_idle;
1275
1276 return result;
1277}
1278
1242#ifdef CONFIG_SMP 1279#ifdef CONFIG_SMP
1243static void smp_callback(void *v) 1280static void smp_callback(void *v)
1244{ 1281{
@@ -1261,7 +1298,360 @@ static int acpi_processor_latency_notify(struct notifier_block *b,
1261static struct notifier_block acpi_processor_latency_notifier = { 1298static struct notifier_block acpi_processor_latency_notifier = {
1262 .notifier_call = acpi_processor_latency_notify, 1299 .notifier_call = acpi_processor_latency_notify,
1263}; 1300};
1301
1302#endif
1303
1304#else /* CONFIG_CPU_IDLE */
1305
1306/**
1307 * acpi_idle_bm_check - checks if bus master activity was detected
1308 */
1309static int acpi_idle_bm_check(void)
1310{
1311 u32 bm_status = 0;
1312
1313 acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
1314 if (bm_status)
1315 acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
1316 /*
1317 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
1318 * the true state of bus mastering activity; forcing us to
1319 * manually check the BMIDEA bit of each IDE channel.
1320 */
1321 else if (errata.piix4.bmisx) {
1322 if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
1323 || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
1324 bm_status = 1;
1325 }
1326 return bm_status;
1327}
1328
1329/**
1330 * acpi_idle_update_bm_rld - updates the BM_RLD bit depending on target state
1331 * @pr: the processor
1332 * @target: the new target state
1333 */
1334static inline void acpi_idle_update_bm_rld(struct acpi_processor *pr,
1335 struct acpi_processor_cx *target)
1336{
1337 if (pr->flags.bm_rld_set && target->type != ACPI_STATE_C3) {
1338 acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0);
1339 pr->flags.bm_rld_set = 0;
1340 }
1341
1342 if (!pr->flags.bm_rld_set && target->type == ACPI_STATE_C3) {
1343 acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1);
1344 pr->flags.bm_rld_set = 1;
1345 }
1346}
1347
1348/**
1349 * acpi_idle_do_entry - a helper function that does C2 and C3 type entry
1350 * @cx: cstate data
1351 */
1352static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
1353{
1354 if (cx->space_id == ACPI_CSTATE_FFH) {
1355 /* Call into architectural FFH based C-state */
1356 acpi_processor_ffh_cstate_enter(cx);
1357 } else {
1358 int unused;
1359 /* IO port based C-state */
1360 inb(cx->address);
1361 /* Dummy wait op - must do something useless after P_LVL2 read
1362 because chipsets cannot guarantee that STPCLK# signal
1363 gets asserted in time to freeze execution properly. */
1364 unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
1365 }
1366}
1367
1368/**
1369 * acpi_idle_enter_c1 - enters an ACPI C1 state-type
1370 * @dev: the target CPU
1371 * @state: the state data
1372 *
1373 * This is equivalent to the HALT instruction.
1374 */
1375static int acpi_idle_enter_c1(struct cpuidle_device *dev,
1376 struct cpuidle_state *state)
1377{
1378 struct acpi_processor *pr;
1379 struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
1380 pr = processors[smp_processor_id()];
1381
1382 if (unlikely(!pr))
1383 return 0;
1384
1385 if (pr->flags.bm_check)
1386 acpi_idle_update_bm_rld(pr, cx);
1387
1388 current_thread_info()->status &= ~TS_POLLING;
1389 /*
1390 * TS_POLLING-cleared state must be visible before we test
1391 * NEED_RESCHED:
1392 */
1393 smp_mb();
1394 if (!need_resched())
1395 safe_halt();
1396 current_thread_info()->status |= TS_POLLING;
1397
1398 cx->usage++;
1399
1400 return 0;
1401}
1402
1403/**
1404 * acpi_idle_enter_simple - enters an ACPI state without BM handling
1405 * @dev: the target CPU
1406 * @state: the state data
1407 */
1408static int acpi_idle_enter_simple(struct cpuidle_device *dev,
1409 struct cpuidle_state *state)
1410{
1411 struct acpi_processor *pr;
1412 struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
1413 u32 t1, t2;
1414 pr = processors[smp_processor_id()];
1415
1416 if (unlikely(!pr))
1417 return 0;
1418
1419 if (pr->flags.bm_check)
1420 acpi_idle_update_bm_rld(pr, cx);
1421
1422 local_irq_disable();
1423 current_thread_info()->status &= ~TS_POLLING;
1424 /*
1425 * TS_POLLING-cleared state must be visible before we test
1426 * NEED_RESCHED:
1427 */
1428 smp_mb();
1429
1430 if (unlikely(need_resched())) {
1431 current_thread_info()->status |= TS_POLLING;
1432 local_irq_enable();
1433 return 0;
1434 }
1435
1436 if (cx->type == ACPI_STATE_C3)
1437 ACPI_FLUSH_CPU_CACHE();
1438
1439 t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
1440 acpi_state_timer_broadcast(pr, cx, 1);
1441 acpi_idle_do_entry(cx);
1442 t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
1443
1444#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
1445 /* TSC could halt in idle, so notify users */
1446 mark_tsc_unstable("TSC halts in idle");;
1447#endif
1448
1449 local_irq_enable();
1450 current_thread_info()->status |= TS_POLLING;
1451
1452 cx->usage++;
1453
1454 acpi_state_timer_broadcast(pr, cx, 0);
1455 cx->time += ticks_elapsed(t1, t2);
1456 return ticks_elapsed_in_us(t1, t2);
1457}
1458
1459static int c3_cpu_count;
1460static DEFINE_SPINLOCK(c3_lock);
1461
1462/**
1463 * acpi_idle_enter_bm - enters C3 with proper BM handling
1464 * @dev: the target CPU
1465 * @state: the state data
1466 *
1467 * If BM is detected, the deepest non-C3 idle state is entered instead.
1468 */
1469static int acpi_idle_enter_bm(struct cpuidle_device *dev,
1470 struct cpuidle_state *state)
1471{
1472 struct acpi_processor *pr;
1473 struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
1474 u32 t1, t2;
1475 pr = processors[smp_processor_id()];
1476
1477 if (unlikely(!pr))
1478 return 0;
1479
1480 local_irq_disable();
1481 current_thread_info()->status &= ~TS_POLLING;
1482 /*
1483 * TS_POLLING-cleared state must be visible before we test
1484 * NEED_RESCHED:
1485 */
1486 smp_mb();
1487
1488 if (unlikely(need_resched())) {
1489 current_thread_info()->status |= TS_POLLING;
1490 local_irq_enable();
1491 return 0;
1492 }
1493
1494 /*
1495 * Must be done before busmaster disable as we might need to
1496 * access HPET !
1497 */
1498 acpi_state_timer_broadcast(pr, cx, 1);
1499
1500 if (acpi_idle_bm_check()) {
1501 cx = pr->power.bm_state;
1502
1503 acpi_idle_update_bm_rld(pr, cx);
1504
1505 t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
1506 acpi_idle_do_entry(cx);
1507 t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
1508 } else {
1509 acpi_idle_update_bm_rld(pr, cx);
1510
1511 spin_lock(&c3_lock);
1512 c3_cpu_count++;
1513 /* Disable bus master arbitration when all CPUs are in C3 */
1514 if (c3_cpu_count == num_online_cpus())
1515 acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1);
1516 spin_unlock(&c3_lock);
1517
1518 t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
1519 acpi_idle_do_entry(cx);
1520 t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
1521
1522 spin_lock(&c3_lock);
1523 /* Re-enable bus master arbitration */
1524 if (c3_cpu_count == num_online_cpus())
1525 acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0);
1526 c3_cpu_count--;
1527 spin_unlock(&c3_lock);
1528 }
1529
1530#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
1531 /* TSC could halt in idle, so notify users */
1532 mark_tsc_unstable("TSC halts in idle");
1533#endif
1534
1535 local_irq_enable();
1536 current_thread_info()->status |= TS_POLLING;
1537
1538 cx->usage++;
1539
1540 acpi_state_timer_broadcast(pr, cx, 0);
1541 cx->time += ticks_elapsed(t1, t2);
1542 return ticks_elapsed_in_us(t1, t2);
1543}
1544
1545struct cpuidle_driver acpi_idle_driver = {
1546 .name = "acpi_idle",
1547 .owner = THIS_MODULE,
1548};
1549
1550/**
1551 * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE
1552 * @pr: the ACPI processor
1553 */
1554static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
1555{
1556 int i, count = 0;
1557 struct acpi_processor_cx *cx;
1558 struct cpuidle_state *state;
1559 struct cpuidle_device *dev = &pr->power.dev;
1560
1561 if (!pr->flags.power_setup_done)
1562 return -EINVAL;
1563
1564 if (pr->flags.power == 0) {
1565 return -EINVAL;
1566 }
1567
1568 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
1569 cx = &pr->power.states[i];
1570 state = &dev->states[count];
1571
1572 if (!cx->valid)
1573 continue;
1574
1575#ifdef CONFIG_HOTPLUG_CPU
1576 if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
1577 !pr->flags.has_cst &&
1578 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
1579 continue;
1264#endif 1580#endif
1581 cpuidle_set_statedata(state, cx);
1582
1583 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
1584 state->exit_latency = cx->latency;
1585 state->target_residency = cx->latency * 6;
1586 state->power_usage = cx->power;
1587
1588 state->flags = 0;
1589 switch (cx->type) {
1590 case ACPI_STATE_C1:
1591 state->flags |= CPUIDLE_FLAG_SHALLOW;
1592 state->enter = acpi_idle_enter_c1;
1593 break;
1594
1595 case ACPI_STATE_C2:
1596 state->flags |= CPUIDLE_FLAG_BALANCED;
1597 state->flags |= CPUIDLE_FLAG_TIME_VALID;
1598 state->enter = acpi_idle_enter_simple;
1599 break;
1600
1601 case ACPI_STATE_C3:
1602 state->flags |= CPUIDLE_FLAG_DEEP;
1603 state->flags |= CPUIDLE_FLAG_TIME_VALID;
1604 state->flags |= CPUIDLE_FLAG_CHECK_BM;
1605 state->enter = pr->flags.bm_check ?
1606 acpi_idle_enter_bm :
1607 acpi_idle_enter_simple;
1608 break;
1609 }
1610
1611 count++;
1612 }
1613
1614 dev->state_count = count;
1615
1616 if (!count)
1617 return -EINVAL;
1618
1619 /* find the deepest state that can handle active BM */
1620 if (pr->flags.bm_check) {
1621 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++)
1622 if (pr->power.states[i].type == ACPI_STATE_C3)
1623 break;
1624 pr->power.bm_state = &pr->power.states[i-1];
1625 }
1626
1627 return 0;
1628}
1629
1630int acpi_processor_cst_has_changed(struct acpi_processor *pr)
1631{
1632 int ret;
1633
1634 if (!pr)
1635 return -EINVAL;
1636
1637 if (nocst) {
1638 return -ENODEV;
1639 }
1640
1641 if (!pr->flags.power_setup_done)
1642 return -ENODEV;
1643
1644 cpuidle_pause_and_lock();
1645 cpuidle_disable_device(&pr->power.dev);
1646 acpi_processor_get_power_info(pr);
1647 acpi_processor_setup_cpuidle(pr);
1648 ret = cpuidle_enable_device(&pr->power.dev);
1649 cpuidle_resume_and_unlock();
1650
1651 return ret;
1652}
1653
1654#endif /* CONFIG_CPU_IDLE */
1265 1655
1266int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, 1656int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
1267 struct acpi_device *device) 1657 struct acpi_device *device)
@@ -1279,7 +1669,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
1279 "ACPI: processor limited to max C-state %d\n", 1669 "ACPI: processor limited to max C-state %d\n",
1280 max_cstate); 1670 max_cstate);
1281 first_run++; 1671 first_run++;
1282#ifdef CONFIG_SMP 1672#if !defined (CONFIG_CPU_IDLE) && defined (CONFIG_SMP)
1283 register_latency_notifier(&acpi_processor_latency_notifier); 1673 register_latency_notifier(&acpi_processor_latency_notifier);
1284#endif 1674#endif
1285 } 1675 }
@@ -1297,6 +1687,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
1297 } 1687 }
1298 1688
1299 acpi_processor_get_power_info(pr); 1689 acpi_processor_get_power_info(pr);
1690 pr->flags.power_setup_done = 1;
1300 1691
1301 /* 1692 /*
1302 * Install the idle handler if processor power management is supported. 1693 * Install the idle handler if processor power management is supported.
@@ -1304,6 +1695,13 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
1304 * platforms that only support C1. 1695 * platforms that only support C1.
1305 */ 1696 */
1306 if ((pr->flags.power) && (!boot_option_idle_override)) { 1697 if ((pr->flags.power) && (!boot_option_idle_override)) {
1698#ifdef CONFIG_CPU_IDLE
1699 acpi_processor_setup_cpuidle(pr);
1700 pr->power.dev.cpu = pr->id;
1701 if (cpuidle_register_device(&pr->power.dev))
1702 return -EIO;
1703#endif
1704
1307 printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); 1705 printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id);
1308 for (i = 1; i <= pr->power.count; i++) 1706 for (i = 1; i <= pr->power.count; i++)
1309 if (pr->power.states[i].valid) 1707 if (pr->power.states[i].valid)
@@ -1311,10 +1709,12 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
1311 pr->power.states[i].type); 1709 pr->power.states[i].type);
1312 printk(")\n"); 1710 printk(")\n");
1313 1711
1712#ifndef CONFIG_CPU_IDLE
1314 if (pr->id == 0) { 1713 if (pr->id == 0) {
1315 pm_idle_save = pm_idle; 1714 pm_idle_save = pm_idle;
1316 pm_idle = acpi_processor_idle; 1715 pm_idle = acpi_processor_idle;
1317 } 1716 }
1717#endif
1318 } 1718 }
1319 1719
1320 /* 'power' [R] */ 1720 /* 'power' [R] */
@@ -1328,21 +1728,24 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
1328 entry->owner = THIS_MODULE; 1728 entry->owner = THIS_MODULE;
1329 } 1729 }
1330 1730
1331 pr->flags.power_setup_done = 1;
1332
1333 return 0; 1731 return 0;
1334} 1732}
1335 1733
1336int acpi_processor_power_exit(struct acpi_processor *pr, 1734int acpi_processor_power_exit(struct acpi_processor *pr,
1337 struct acpi_device *device) 1735 struct acpi_device *device)
1338{ 1736{
1339 1737#ifdef CONFIG_CPU_IDLE
1738 if ((pr->flags.power) && (!boot_option_idle_override))
1739 cpuidle_unregister_device(&pr->power.dev);
1740#endif
1340 pr->flags.power_setup_done = 0; 1741 pr->flags.power_setup_done = 0;
1341 1742
1342 if (acpi_device_dir(device)) 1743 if (acpi_device_dir(device))
1343 remove_proc_entry(ACPI_PROCESSOR_FILE_POWER, 1744 remove_proc_entry(ACPI_PROCESSOR_FILE_POWER,
1344 acpi_device_dir(device)); 1745 acpi_device_dir(device));
1345 1746
1747#ifndef CONFIG_CPU_IDLE
1748
1346 /* Unregister the idle handler when processor #0 is removed. */ 1749 /* Unregister the idle handler when processor #0 is removed. */
1347 if (pr->id == 0) { 1750 if (pr->id == 0) {
1348 pm_idle = pm_idle_save; 1751 pm_idle = pm_idle_save;
@@ -1357,6 +1760,7 @@ int acpi_processor_power_exit(struct acpi_processor *pr,
1357 unregister_latency_notifier(&acpi_processor_latency_notifier); 1760 unregister_latency_notifier(&acpi_processor_latency_notifier);
1358#endif 1761#endif
1359 } 1762 }
1763#endif
1360 1764
1361 return 0; 1765 return 0;
1362} 1766}
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
new file mode 100644
index 000000000000..3bed4127d4ad
--- /dev/null
+++ b/drivers/cpuidle/Kconfig
@@ -0,0 +1,20 @@
1
2config CPU_IDLE
3 bool "CPU idle PM support"
4 help
5 CPU idle is a generic framework for supporting software-controlled
6 idle processor power management. It includes modular cross-platform
7 governors that can be swapped during runtime.
8
9 If you're using a mobile platform that supports CPU idle PM (e.g.
10 an ACPI-capable notebook), you should say Y here.
11
12config CPU_IDLE_GOV_LADDER
13 bool
14 depends on CPU_IDLE
15 default y
16
17config CPU_IDLE_GOV_MENU
18 bool
19 depends on CPU_IDLE && NO_HZ
20 default y
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
new file mode 100644
index 000000000000..5634f88379df
--- /dev/null
+++ b/drivers/cpuidle/Makefile
@@ -0,0 +1,5 @@
1#
2# Makefile for cpuidle.
3#
4
5obj-y += cpuidle.o driver.o governor.o sysfs.o governors/
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
new file mode 100644
index 000000000000..fdf4106b817b
--- /dev/null
+++ b/drivers/cpuidle/cpuidle.c
@@ -0,0 +1,295 @@
1/*
2 * cpuidle.c - core cpuidle infrastructure
3 *
4 * (C) 2006-2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Shaohua Li <shaohua.li@intel.com>
6 * Adam Belay <abelay@novell.com>
7 *
8 * This code is licenced under the GPL.
9 */
10
11#include <linux/kernel.h>
12#include <linux/mutex.h>
13#include <linux/sched.h>
14#include <linux/notifier.h>
15#include <linux/latency.h>
16#include <linux/cpu.h>
17#include <linux/cpuidle.h>
18
19#include "cpuidle.h"
20
21DEFINE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
22EXPORT_PER_CPU_SYMBOL_GPL(cpuidle_devices);
23
24DEFINE_MUTEX(cpuidle_lock);
25LIST_HEAD(cpuidle_detected_devices);
26static void (*pm_idle_old)(void);
27
28static int enabled_devices;
29
30/**
31 * cpuidle_idle_call - the main idle loop
32 *
33 * NOTE: no locks or semaphores should be used here
34 */
35static void cpuidle_idle_call(void)
36{
37 struct cpuidle_device *dev = __get_cpu_var(cpuidle_devices);
38 struct cpuidle_state *target_state;
39 int next_state;
40
41 /* check if the device is ready */
42 if (!dev || !dev->enabled) {
43 if (pm_idle_old)
44 pm_idle_old();
45 else
46 local_irq_enable();
47 return;
48 }
49
50 /* ask the governor for the next state */
51 next_state = cpuidle_curr_governor->select(dev);
52 if (need_resched())
53 return;
54 target_state = &dev->states[next_state];
55
56 /* enter the state and update stats */
57 dev->last_residency = target_state->enter(dev, target_state);
58 dev->last_state = target_state;
59 target_state->time += dev->last_residency;
60 target_state->usage++;
61
62 /* give the governor an opportunity to reflect on the outcome */
63 if (cpuidle_curr_governor->reflect)
64 cpuidle_curr_governor->reflect(dev);
65}
66
67/**
68 * cpuidle_install_idle_handler - installs the cpuidle idle loop handler
69 */
70void cpuidle_install_idle_handler(void)
71{
72 if (enabled_devices && (pm_idle != cpuidle_idle_call)) {
73 /* Make sure all changes finished before we switch to new idle */
74 smp_wmb();
75 pm_idle = cpuidle_idle_call;
76 }
77}
78
79/**
80 * cpuidle_uninstall_idle_handler - uninstalls the cpuidle idle loop handler
81 */
82void cpuidle_uninstall_idle_handler(void)
83{
84 if (enabled_devices && (pm_idle != pm_idle_old)) {
85 pm_idle = pm_idle_old;
86 cpu_idle_wait();
87 }
88}
89
90/**
91 * cpuidle_pause_and_lock - temporarily disables CPUIDLE
92 */
93void cpuidle_pause_and_lock(void)
94{
95 mutex_lock(&cpuidle_lock);
96 cpuidle_uninstall_idle_handler();
97}
98
99EXPORT_SYMBOL_GPL(cpuidle_pause_and_lock);
100
101/**
102 * cpuidle_resume_and_unlock - resumes CPUIDLE operation
103 */
104void cpuidle_resume_and_unlock(void)
105{
106 cpuidle_install_idle_handler();
107 mutex_unlock(&cpuidle_lock);
108}
109
110EXPORT_SYMBOL_GPL(cpuidle_resume_and_unlock);
111
112/**
113 * cpuidle_enable_device - enables idle PM for a CPU
114 * @dev: the CPU
115 *
116 * This function must be called between cpuidle_pause_and_lock and
117 * cpuidle_resume_and_unlock when used externally.
118 */
119int cpuidle_enable_device(struct cpuidle_device *dev)
120{
121 int ret, i;
122
123 if (dev->enabled)
124 return 0;
125 if (!cpuidle_curr_driver || !cpuidle_curr_governor)
126 return -EIO;
127 if (!dev->state_count)
128 return -EINVAL;
129
130 if ((ret = cpuidle_add_state_sysfs(dev)))
131 return ret;
132
133 if (cpuidle_curr_governor->enable &&
134 (ret = cpuidle_curr_governor->enable(dev)))
135 goto fail_sysfs;
136
137 for (i = 0; i < dev->state_count; i++) {
138 dev->states[i].usage = 0;
139 dev->states[i].time = 0;
140 }
141 dev->last_residency = 0;
142 dev->last_state = NULL;
143
144 smp_wmb();
145
146 dev->enabled = 1;
147
148 enabled_devices++;
149 return 0;
150
151fail_sysfs:
152 cpuidle_remove_state_sysfs(dev);
153
154 return ret;
155}
156
157EXPORT_SYMBOL_GPL(cpuidle_enable_device);
158
159/**
160 * cpuidle_disable_device - disables idle PM for a CPU
161 * @dev: the CPU
162 *
163 * This function must be called between cpuidle_pause_and_lock and
164 * cpuidle_resume_and_unlock when used externally.
165 */
166void cpuidle_disable_device(struct cpuidle_device *dev)
167{
168 if (!dev->enabled)
169 return;
170 if (!cpuidle_curr_driver || !cpuidle_curr_governor)
171 return;
172
173 dev->enabled = 0;
174
175 if (cpuidle_curr_governor->disable)
176 cpuidle_curr_governor->disable(dev);
177
178 cpuidle_remove_state_sysfs(dev);
179 enabled_devices--;
180}
181
182EXPORT_SYMBOL_GPL(cpuidle_disable_device);
183
184/**
185 * cpuidle_register_device - registers a CPU's idle PM feature
186 * @dev: the cpu
187 */
188int cpuidle_register_device(struct cpuidle_device *dev)
189{
190 int ret;
191 struct sys_device *sys_dev = get_cpu_sysdev((unsigned long)dev->cpu);
192
193 if (!sys_dev)
194 return -EINVAL;
195 if (!try_module_get(cpuidle_curr_driver->owner))
196 return -EINVAL;
197
198 init_completion(&dev->kobj_unregister);
199
200 mutex_lock(&cpuidle_lock);
201
202 per_cpu(cpuidle_devices, dev->cpu) = dev;
203 list_add(&dev->device_list, &cpuidle_detected_devices);
204 if ((ret = cpuidle_add_sysfs(sys_dev))) {
205 mutex_unlock(&cpuidle_lock);
206 module_put(cpuidle_curr_driver->owner);
207 return ret;
208 }
209
210 cpuidle_enable_device(dev);
211 cpuidle_install_idle_handler();
212
213 mutex_unlock(&cpuidle_lock);
214
215 return 0;
216
217}
218
219EXPORT_SYMBOL_GPL(cpuidle_register_device);
220
221/**
222 * cpuidle_unregister_device - unregisters a CPU's idle PM feature
223 * @dev: the cpu
224 */
225void cpuidle_unregister_device(struct cpuidle_device *dev)
226{
227 struct sys_device *sys_dev = get_cpu_sysdev((unsigned long)dev->cpu);
228
229 cpuidle_pause_and_lock();
230
231 cpuidle_disable_device(dev);
232
233 cpuidle_remove_sysfs(sys_dev);
234 list_del(&dev->device_list);
235 wait_for_completion(&dev->kobj_unregister);
236 per_cpu(cpuidle_devices, dev->cpu) = NULL;
237
238 cpuidle_resume_and_unlock();
239
240 module_put(cpuidle_curr_driver->owner);
241}
242
243EXPORT_SYMBOL_GPL(cpuidle_unregister_device);
244
245#ifdef CONFIG_SMP
246
247static void smp_callback(void *v)
248{
249 /* we already woke the CPU up, nothing more to do */
250}
251
252/*
253 * This function gets called when a part of the kernel has a new latency
254 * requirement. This means we need to get all processors out of their C-state,
255 * and then recalculate a new suitable C-state. Just do a cross-cpu IPI; that
256 * wakes them all right up.
257 */
258static int cpuidle_latency_notify(struct notifier_block *b,
259 unsigned long l, void *v)
260{
261 smp_call_function(smp_callback, NULL, 0, 1);
262 return NOTIFY_OK;
263}
264
265static struct notifier_block cpuidle_latency_notifier = {
266 .notifier_call = cpuidle_latency_notify,
267};
268
269#define latency_notifier_init(x) do { register_latency_notifier(x); } while (0)
270
271#else /* CONFIG_SMP */
272
273#define latency_notifier_init(x) do { } while (0)
274
275#endif /* CONFIG_SMP */
276
277/**
278 * cpuidle_init - core initializer
279 */
280static int __init cpuidle_init(void)
281{
282 int ret;
283
284 pm_idle_old = pm_idle;
285
286 ret = cpuidle_add_class_sysfs(&cpu_sysdev_class);
287 if (ret)
288 return ret;
289
290 latency_notifier_init(&cpuidle_latency_notifier);
291
292 return 0;
293}
294
295core_initcall(cpuidle_init);
diff --git a/drivers/cpuidle/cpuidle.h b/drivers/cpuidle/cpuidle.h
new file mode 100644
index 000000000000..9476ba33ee2c
--- /dev/null
+++ b/drivers/cpuidle/cpuidle.h
@@ -0,0 +1,33 @@
1/*
2 * cpuidle.h - The internal header file
3 */
4
5#ifndef __DRIVER_CPUIDLE_H
6#define __DRIVER_CPUIDLE_H
7
8#include <linux/sysdev.h>
9
10/* For internal use only */
11extern struct cpuidle_governor *cpuidle_curr_governor;
12extern struct cpuidle_driver *cpuidle_curr_driver;
13extern struct list_head cpuidle_governors;
14extern struct list_head cpuidle_detected_devices;
15extern struct mutex cpuidle_lock;
16extern spinlock_t cpuidle_driver_lock;
17
18/* idle loop */
19extern void cpuidle_install_idle_handler(void);
20extern void cpuidle_uninstall_idle_handler(void);
21
22/* governors */
23extern int cpuidle_switch_governor(struct cpuidle_governor *gov);
24
25/* sysfs */
26extern int cpuidle_add_class_sysfs(struct sysdev_class *cls);
27extern void cpuidle_remove_class_sysfs(struct sysdev_class *cls);
28extern int cpuidle_add_state_sysfs(struct cpuidle_device *device);
29extern void cpuidle_remove_state_sysfs(struct cpuidle_device *device);
30extern int cpuidle_add_sysfs(struct sys_device *sysdev);
31extern void cpuidle_remove_sysfs(struct sys_device *sysdev);
32
33#endif /* __DRIVER_CPUIDLE_H */
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
new file mode 100644
index 000000000000..2257004fe33d
--- /dev/null
+++ b/drivers/cpuidle/driver.c
@@ -0,0 +1,56 @@
1/*
2 * driver.c - driver support
3 *
4 * (C) 2006-2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Shaohua Li <shaohua.li@intel.com>
6 * Adam Belay <abelay@novell.com>
7 *
8 * This code is licenced under the GPL.
9 */
10
11#include <linux/mutex.h>
12#include <linux/module.h>
13#include <linux/cpuidle.h>
14
15#include "cpuidle.h"
16
17struct cpuidle_driver *cpuidle_curr_driver;
18DEFINE_SPINLOCK(cpuidle_driver_lock);
19
20/**
21 * cpuidle_register_driver - registers a driver
22 * @drv: the driver
23 */
24int cpuidle_register_driver(struct cpuidle_driver *drv)
25{
26 if (!drv)
27 return -EINVAL;
28
29 spin_lock(&cpuidle_driver_lock);
30 if (cpuidle_curr_driver) {
31 spin_unlock(&cpuidle_driver_lock);
32 return -EBUSY;
33 }
34 cpuidle_curr_driver = drv;
35 spin_unlock(&cpuidle_driver_lock);
36
37 return 0;
38}
39
40EXPORT_SYMBOL_GPL(cpuidle_register_driver);
41
42/**
43 * cpuidle_unregister_driver - unregisters a driver
44 * @drv: the driver
45 */
46void cpuidle_unregister_driver(struct cpuidle_driver *drv)
47{
48 if (!drv)
49 return;
50
51 spin_lock(&cpuidle_driver_lock);
52 cpuidle_curr_driver = NULL;
53 spin_unlock(&cpuidle_driver_lock);
54}
55
56EXPORT_SYMBOL_GPL(cpuidle_unregister_driver);
diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c
new file mode 100644
index 000000000000..bb699cb2dc5a
--- /dev/null
+++ b/drivers/cpuidle/governor.c
@@ -0,0 +1,141 @@
1/*
2 * governor.c - governor support
3 *
4 * (C) 2006-2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Shaohua Li <shaohua.li@intel.com>
6 * Adam Belay <abelay@novell.com>
7 *
8 * This code is licenced under the GPL.
9 */
10
11#include <linux/mutex.h>
12#include <linux/module.h>
13#include <linux/cpuidle.h>
14
15#include "cpuidle.h"
16
17LIST_HEAD(cpuidle_governors);
18struct cpuidle_governor *cpuidle_curr_governor;
19
20/**
21 * __cpuidle_find_governor - finds a governor of the specified name
22 * @str: the name
23 *
24 * Must be called with cpuidle_lock aquired.
25 */
26static struct cpuidle_governor * __cpuidle_find_governor(const char *str)
27{
28 struct cpuidle_governor *gov;
29
30 list_for_each_entry(gov, &cpuidle_governors, governor_list)
31 if (!strnicmp(str, gov->name, CPUIDLE_NAME_LEN))
32 return gov;
33
34 return NULL;
35}
36
37/**
38 * cpuidle_switch_governor - changes the governor
39 * @gov: the new target governor
40 *
41 * NOTE: "gov" can be NULL to specify disabled
42 * Must be called with cpuidle_lock aquired.
43 */
44int cpuidle_switch_governor(struct cpuidle_governor *gov)
45{
46 struct cpuidle_device *dev;
47
48 if (gov == cpuidle_curr_governor)
49 return 0;
50
51 cpuidle_uninstall_idle_handler();
52
53 if (cpuidle_curr_governor) {
54 list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
55 cpuidle_disable_device(dev);
56 module_put(cpuidle_curr_governor->owner);
57 }
58
59 cpuidle_curr_governor = gov;
60
61 if (gov) {
62 if (!try_module_get(cpuidle_curr_governor->owner))
63 return -EINVAL;
64 list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
65 cpuidle_enable_device(dev);
66 cpuidle_install_idle_handler();
67 printk(KERN_INFO "cpuidle: using governor %s\n", gov->name);
68 }
69
70 return 0;
71}
72
73/**
74 * cpuidle_register_governor - registers a governor
75 * @gov: the governor
76 */
77int cpuidle_register_governor(struct cpuidle_governor *gov)
78{
79 int ret = -EEXIST;
80
81 if (!gov || !gov->select)
82 return -EINVAL;
83
84 mutex_lock(&cpuidle_lock);
85 if (__cpuidle_find_governor(gov->name) == NULL) {
86 ret = 0;
87 list_add_tail(&gov->governor_list, &cpuidle_governors);
88 if (!cpuidle_curr_governor ||
89 cpuidle_curr_governor->rating < gov->rating)
90 cpuidle_switch_governor(gov);
91 }
92 mutex_unlock(&cpuidle_lock);
93
94 return ret;
95}
96
97EXPORT_SYMBOL_GPL(cpuidle_register_governor);
98
99/**
100 * cpuidle_replace_governor - find a replacement governor
101 * @exclude_rating: the rating that will be skipped while looking for
102 * new governor.
103 */
104static struct cpuidle_governor *cpuidle_replace_governor(int exclude_rating)
105{
106 struct cpuidle_governor *gov;
107 struct cpuidle_governor *ret_gov = NULL;
108 unsigned int max_rating = 0;
109
110 list_for_each_entry(gov, &cpuidle_governors, governor_list) {
111 if (gov->rating == exclude_rating)
112 continue;
113 if (gov->rating > max_rating) {
114 max_rating = gov->rating;
115 ret_gov = gov;
116 }
117 }
118
119 return ret_gov;
120}
121
122/**
123 * cpuidle_unregister_governor - unregisters a governor
124 * @gov: the governor
125 */
126void cpuidle_unregister_governor(struct cpuidle_governor *gov)
127{
128 if (!gov)
129 return;
130
131 mutex_lock(&cpuidle_lock);
132 if (gov == cpuidle_curr_governor) {
133 struct cpuidle_governor *new_gov;
134 new_gov = cpuidle_replace_governor(gov->rating);
135 cpuidle_switch_governor(new_gov);
136 }
137 list_del(&gov->governor_list);
138 mutex_unlock(&cpuidle_lock);
139}
140
141EXPORT_SYMBOL_GPL(cpuidle_unregister_governor);
diff --git a/drivers/cpuidle/governors/Makefile b/drivers/cpuidle/governors/Makefile
new file mode 100644
index 000000000000..1b512722689f
--- /dev/null
+++ b/drivers/cpuidle/governors/Makefile
@@ -0,0 +1,6 @@
1#
2# Makefile for cpuidle governors.
3#
4
5obj-$(CONFIG_CPU_IDLE_GOV_LADDER) += ladder.o
6obj-$(CONFIG_CPU_IDLE_GOV_MENU) += menu.o
diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
new file mode 100644
index 000000000000..eb666ecae7c9
--- /dev/null
+++ b/drivers/cpuidle/governors/ladder.c
@@ -0,0 +1,166 @@
1/*
2 * ladder.c - the residency ladder algorithm
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de>
7 *
8 * (C) 2006-2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
9 * Shaohua Li <shaohua.li@intel.com>
10 * Adam Belay <abelay@novell.com>
11 *
12 * This code is licenced under the GPL.
13 */
14
15#include <linux/kernel.h>
16#include <linux/cpuidle.h>
17#include <linux/latency.h>
18#include <linux/moduleparam.h>
19#include <linux/jiffies.h>
20
21#include <asm/io.h>
22#include <asm/uaccess.h>
23
24#define PROMOTION_COUNT 4
25#define DEMOTION_COUNT 1
26
27struct ladder_device_state {
28 struct {
29 u32 promotion_count;
30 u32 demotion_count;
31 u32 promotion_time;
32 u32 demotion_time;
33 } threshold;
34 struct {
35 int promotion_count;
36 int demotion_count;
37 } stats;
38};
39
40struct ladder_device {
41 struct ladder_device_state states[CPUIDLE_STATE_MAX];
42 int last_state_idx;
43};
44
45static DEFINE_PER_CPU(struct ladder_device, ladder_devices);
46
47/**
48 * ladder_do_selection - prepares private data for a state change
49 * @ldev: the ladder device
50 * @old_idx: the current state index
51 * @new_idx: the new target state index
52 */
53static inline void ladder_do_selection(struct ladder_device *ldev,
54 int old_idx, int new_idx)
55{
56 ldev->states[old_idx].stats.promotion_count = 0;
57 ldev->states[old_idx].stats.demotion_count = 0;
58 ldev->last_state_idx = new_idx;
59}
60
61/**
62 * ladder_select_state - selects the next state to enter
63 * @dev: the CPU
64 */
65static int ladder_select_state(struct cpuidle_device *dev)
66{
67 struct ladder_device *ldev = &__get_cpu_var(ladder_devices);
68 struct ladder_device_state *last_state;
69 int last_residency, last_idx = ldev->last_state_idx;
70
71 if (unlikely(!ldev))
72 return 0;
73
74 last_state = &ldev->states[last_idx];
75
76 if (dev->states[last_idx].flags & CPUIDLE_FLAG_TIME_VALID)
77 last_residency = cpuidle_get_last_residency(dev) - dev->states[last_idx].exit_latency;
78 else
79 last_residency = last_state->threshold.promotion_time + 1;
80
81 /* consider promotion */
82 if (last_idx < dev->state_count - 1 &&
83 last_residency > last_state->threshold.promotion_time &&
84 dev->states[last_idx + 1].exit_latency <= system_latency_constraint()) {
85 last_state->stats.promotion_count++;
86 last_state->stats.demotion_count = 0;
87 if (last_state->stats.promotion_count >= last_state->threshold.promotion_count) {
88 ladder_do_selection(ldev, last_idx, last_idx + 1);
89 return last_idx + 1;
90 }
91 }
92
93 /* consider demotion */
94 if (last_idx > 0 &&
95 last_residency < last_state->threshold.demotion_time) {
96 last_state->stats.demotion_count++;
97 last_state->stats.promotion_count = 0;
98 if (last_state->stats.demotion_count >= last_state->threshold.demotion_count) {
99 ladder_do_selection(ldev, last_idx, last_idx - 1);
100 return last_idx - 1;
101 }
102 }
103
104 /* otherwise remain at the current state */
105 return last_idx;
106}
107
108/**
109 * ladder_enable_device - setup for the governor
110 * @dev: the CPU
111 */
112static int ladder_enable_device(struct cpuidle_device *dev)
113{
114 int i;
115 struct ladder_device *ldev = &per_cpu(ladder_devices, dev->cpu);
116 struct ladder_device_state *lstate;
117 struct cpuidle_state *state;
118
119 ldev->last_state_idx = 0;
120
121 for (i = 0; i < dev->state_count; i++) {
122 state = &dev->states[i];
123 lstate = &ldev->states[i];
124
125 lstate->stats.promotion_count = 0;
126 lstate->stats.demotion_count = 0;
127
128 lstate->threshold.promotion_count = PROMOTION_COUNT;
129 lstate->threshold.demotion_count = DEMOTION_COUNT;
130
131 if (i < dev->state_count - 1)
132 lstate->threshold.promotion_time = state->exit_latency;
133 if (i > 0)
134 lstate->threshold.demotion_time = state->exit_latency;
135 }
136
137 return 0;
138}
139
140static struct cpuidle_governor ladder_governor = {
141 .name = "ladder",
142 .rating = 10,
143 .enable = ladder_enable_device,
144 .select = ladder_select_state,
145 .owner = THIS_MODULE,
146};
147
148/**
149 * init_ladder - initializes the governor
150 */
151static int __init init_ladder(void)
152{
153 return cpuidle_register_governor(&ladder_governor);
154}
155
156/**
157 * exit_ladder - exits the governor
158 */
159static void __exit exit_ladder(void)
160{
161 cpuidle_unregister_governor(&ladder_governor);
162}
163
164MODULE_LICENSE("GPL");
165module_init(init_ladder);
166module_exit(exit_ladder);
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
new file mode 100644
index 000000000000..299d45c3bdd2
--- /dev/null
+++ b/drivers/cpuidle/governors/menu.c
@@ -0,0 +1,137 @@
1/*
2 * menu.c - the menu idle governor
3 *
4 * Copyright (C) 2006-2007 Adam Belay <abelay@novell.com>
5 *
6 * This code is licenced under the GPL.
7 */
8
9#include <linux/kernel.h>
10#include <linux/cpuidle.h>
11#include <linux/latency.h>
12#include <linux/time.h>
13#include <linux/ktime.h>
14#include <linux/hrtimer.h>
15#include <linux/tick.h>
16
17#define BREAK_FUZZ 4 /* 4 us */
18
19struct menu_device {
20 int last_state_idx;
21
22 unsigned int expected_us;
23 unsigned int predicted_us;
24 unsigned int last_measured_us;
25 unsigned int elapsed_us;
26};
27
28static DEFINE_PER_CPU(struct menu_device, menu_devices);
29
30/**
31 * menu_select - selects the next idle state to enter
32 * @dev: the CPU
33 */
34static int menu_select(struct cpuidle_device *dev)
35{
36 struct menu_device *data = &__get_cpu_var(menu_devices);
37 int i;
38
39 /* determine the expected residency time */
40 data->expected_us =
41 (u32) ktime_to_ns(tick_nohz_get_sleep_length()) / 1000;
42
43 /* find the deepest idle state that satisfies our constraints */
44 for (i = 1; i < dev->state_count; i++) {
45 struct cpuidle_state *s = &dev->states[i];
46
47 if (s->target_residency > data->expected_us)
48 break;
49 if (s->target_residency > data->predicted_us)
50 break;
51 if (s->exit_latency > system_latency_constraint())
52 break;
53 }
54
55 data->last_state_idx = i - 1;
56 return i - 1;
57}
58
59/**
60 * menu_reflect - attempts to guess what happened after entry
61 * @dev: the CPU
62 *
63 * NOTE: it's important to be fast here because this operation will add to
64 * the overall exit latency.
65 */
66static void menu_reflect(struct cpuidle_device *dev)
67{
68 struct menu_device *data = &__get_cpu_var(menu_devices);
69 int last_idx = data->last_state_idx;
70 unsigned int measured_us =
71 cpuidle_get_last_residency(dev) + data->elapsed_us;
72 struct cpuidle_state *target = &dev->states[last_idx];
73
74 /*
75 * Ugh, this idle state doesn't support residency measurements, so we
76 * are basically lost in the dark. As a compromise, assume we slept
77 * for one full standard timer tick. However, be aware that this
78 * could potentially result in a suboptimal state transition.
79 */
80 if (!(target->flags & CPUIDLE_FLAG_TIME_VALID))
81 measured_us = USEC_PER_SEC / HZ;
82
83 /* Predict time remaining until next break event */
84 if (measured_us + BREAK_FUZZ < data->expected_us - target->exit_latency) {
85 data->predicted_us = max(measured_us, data->last_measured_us);
86 data->last_measured_us = measured_us;
87 data->elapsed_us = 0;
88 } else {
89 if (data->elapsed_us < data->elapsed_us + measured_us)
90 data->elapsed_us = measured_us;
91 else
92 data->elapsed_us = -1;
93 data->predicted_us = max(measured_us, data->last_measured_us);
94 }
95}
96
97/**
98 * menu_enable_device - scans a CPU's states and does setup
99 * @dev: the CPU
100 */
101static int menu_enable_device(struct cpuidle_device *dev)
102{
103 struct menu_device *data = &per_cpu(menu_devices, dev->cpu);
104
105 memset(data, 0, sizeof(struct menu_device));
106
107 return 0;
108}
109
110static struct cpuidle_governor menu_governor = {
111 .name = "menu",
112 .rating = 20,
113 .enable = menu_enable_device,
114 .select = menu_select,
115 .reflect = menu_reflect,
116 .owner = THIS_MODULE,
117};
118
119/**
120 * init_menu - initializes the governor
121 */
122static int __init init_menu(void)
123{
124 return cpuidle_register_governor(&menu_governor);
125}
126
127/**
128 * exit_menu - exits the governor
129 */
130static void __exit exit_menu(void)
131{
132 cpuidle_unregister_governor(&menu_governor);
133}
134
135MODULE_LICENSE("GPL");
136module_init(init_menu);
137module_exit(exit_menu);
diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
new file mode 100644
index 000000000000..0f3515e77d4b
--- /dev/null
+++ b/drivers/cpuidle/sysfs.c
@@ -0,0 +1,361 @@
1/*
2 * sysfs.c - sysfs support
3 *
4 * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com>
5 *
6 * This code is licenced under the GPL.
7 */
8
9#include <linux/kernel.h>
10#include <linux/cpuidle.h>
11#include <linux/sysfs.h>
12#include <linux/cpu.h>
13
14#include "cpuidle.h"
15
16static unsigned int sysfs_switch;
17static int __init cpuidle_sysfs_setup(char *unused)
18{
19 sysfs_switch = 1;
20 return 1;
21}
22__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);
23
24static ssize_t show_available_governors(struct sys_device *dev, char *buf)
25{
26 ssize_t i = 0;
27 struct cpuidle_governor *tmp;
28
29 mutex_lock(&cpuidle_lock);
30 list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
31 if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
32 goto out;
33 i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
34 }
35
36out:
37 i+= sprintf(&buf[i], "\n");
38 mutex_unlock(&cpuidle_lock);
39 return i;
40}
41
42static ssize_t show_current_driver(struct sys_device *dev, char *buf)
43{
44 ssize_t ret;
45
46 spin_lock(&cpuidle_driver_lock);
47 if (cpuidle_curr_driver)
48 ret = sprintf(buf, "%s\n", cpuidle_curr_driver->name);
49 else
50 ret = sprintf(buf, "none\n");
51 spin_unlock(&cpuidle_driver_lock);
52
53 return ret;
54}
55
56static ssize_t show_current_governor(struct sys_device *dev, char *buf)
57{
58 ssize_t ret;
59
60 mutex_lock(&cpuidle_lock);
61 if (cpuidle_curr_governor)
62 ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
63 else
64 ret = sprintf(buf, "none\n");
65 mutex_unlock(&cpuidle_lock);
66
67 return ret;
68}
69
70static ssize_t store_current_governor(struct sys_device *dev,
71 const char *buf, size_t count)
72{
73 char gov_name[CPUIDLE_NAME_LEN];
74 int ret = -EINVAL;
75 size_t len = count;
76 struct cpuidle_governor *gov;
77
78 if (!len || len >= sizeof(gov_name))
79 return -EINVAL;
80
81 memcpy(gov_name, buf, len);
82 gov_name[len] = '\0';
83 if (gov_name[len - 1] == '\n')
84 gov_name[--len] = '\0';
85
86 mutex_lock(&cpuidle_lock);
87
88 list_for_each_entry(gov, &cpuidle_governors, governor_list) {
89 if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
90 ret = cpuidle_switch_governor(gov);
91 break;
92 }
93 }
94
95 mutex_unlock(&cpuidle_lock);
96
97 if (ret)
98 return ret;
99 else
100 return count;
101}
102
103static SYSDEV_ATTR(current_driver, 0444, show_current_driver, NULL);
104static SYSDEV_ATTR(current_governor_ro, 0444, show_current_governor, NULL);
105
106static struct attribute *cpuclass_default_attrs[] = {
107 &attr_current_driver.attr,
108 &attr_current_governor_ro.attr,
109 NULL
110};
111
112static SYSDEV_ATTR(available_governors, 0444, show_available_governors, NULL);
113static SYSDEV_ATTR(current_governor, 0644, show_current_governor,
114 store_current_governor);
115
116static struct attribute *cpuclass_switch_attrs[] = {
117 &attr_available_governors.attr,
118 &attr_current_driver.attr,
119 &attr_current_governor.attr,
120 NULL
121};
122
123static struct attribute_group cpuclass_attr_group = {
124 .attrs = cpuclass_default_attrs,
125 .name = "cpuidle",
126};
127
128/**
129 * cpuidle_add_class_sysfs - add CPU global sysfs attributes
130 */
131int cpuidle_add_class_sysfs(struct sysdev_class *cls)
132{
133 if (sysfs_switch)
134 cpuclass_attr_group.attrs = cpuclass_switch_attrs;
135
136 return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
137}
138
139/**
140 * cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
141 */
142void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
143{
144 sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group);
145}
146
147struct cpuidle_attr {
148 struct attribute attr;
149 ssize_t (*show)(struct cpuidle_device *, char *);
150 ssize_t (*store)(struct cpuidle_device *, const char *, size_t count);
151};
152
153#define define_one_ro(_name, show) \
154 static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
155#define define_one_rw(_name, show, store) \
156 static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)
157
158#define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
159#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
160static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
161{
162 int ret = -EIO;
163 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
164 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
165
166 if (cattr->show) {
167 mutex_lock(&cpuidle_lock);
168 ret = cattr->show(dev, buf);
169 mutex_unlock(&cpuidle_lock);
170 }
171 return ret;
172}
173
174static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
175 const char * buf, size_t count)
176{
177 int ret = -EIO;
178 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
179 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
180
181 if (cattr->store) {
182 mutex_lock(&cpuidle_lock);
183 ret = cattr->store(dev, buf, count);
184 mutex_unlock(&cpuidle_lock);
185 }
186 return ret;
187}
188
189static struct sysfs_ops cpuidle_sysfs_ops = {
190 .show = cpuidle_show,
191 .store = cpuidle_store,
192};
193
194static void cpuidle_sysfs_release(struct kobject *kobj)
195{
196 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
197
198 complete(&dev->kobj_unregister);
199}
200
201static struct kobj_type ktype_cpuidle = {
202 .sysfs_ops = &cpuidle_sysfs_ops,
203 .release = cpuidle_sysfs_release,
204};
205
206struct cpuidle_state_attr {
207 struct attribute attr;
208 ssize_t (*show)(struct cpuidle_state *, char *);
209 ssize_t (*store)(struct cpuidle_state *, const char *, size_t);
210};
211
212#define define_one_state_ro(_name, show) \
213static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
214
215#define define_show_state_function(_name) \
216static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
217{ \
218 return sprintf(buf, "%u\n", state->_name);\
219}
220
221static ssize_t show_state_name(struct cpuidle_state *state, char *buf)
222{
223 return sprintf(buf, "%s\n", state->name);
224}
225
226define_show_state_function(exit_latency)
227define_show_state_function(power_usage)
228define_show_state_function(usage)
229define_show_state_function(time)
230define_one_state_ro(name, show_state_name);
231define_one_state_ro(latency, show_state_exit_latency);
232define_one_state_ro(power, show_state_power_usage);
233define_one_state_ro(usage, show_state_usage);
234define_one_state_ro(time, show_state_time);
235
236static struct attribute *cpuidle_state_default_attrs[] = {
237 &attr_name.attr,
238 &attr_latency.attr,
239 &attr_power.attr,
240 &attr_usage.attr,
241 &attr_time.attr,
242 NULL
243};
244
245#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
246#define kobj_to_state(k) (kobj_to_state_obj(k)->state)
247#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
248static ssize_t cpuidle_state_show(struct kobject * kobj,
249 struct attribute * attr ,char * buf)
250{
251 int ret = -EIO;
252 struct cpuidle_state *state = kobj_to_state(kobj);
253 struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
254
255 if (cattr->show)
256 ret = cattr->show(state, buf);
257
258 return ret;
259}
260
261static struct sysfs_ops cpuidle_state_sysfs_ops = {
262 .show = cpuidle_state_show,
263};
264
265static void cpuidle_state_sysfs_release(struct kobject *kobj)
266{
267 struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
268
269 complete(&state_obj->kobj_unregister);
270}
271
272static struct kobj_type ktype_state_cpuidle = {
273 .sysfs_ops = &cpuidle_state_sysfs_ops,
274 .default_attrs = cpuidle_state_default_attrs,
275 .release = cpuidle_state_sysfs_release,
276};
277
278static void inline cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
279{
280 kobject_unregister(&device->kobjs[i]->kobj);
281 wait_for_completion(&device->kobjs[i]->kobj_unregister);
282 kfree(device->kobjs[i]);
283 device->kobjs[i] = NULL;
284}
285
286/**
287 * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
288 * @device: the target device
289 */
290int cpuidle_add_state_sysfs(struct cpuidle_device *device)
291{
292 int i, ret = -ENOMEM;
293 struct cpuidle_state_kobj *kobj;
294
295 /* state statistics */
296 for (i = 0; i < device->state_count; i++) {
297 kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
298 if (!kobj)
299 goto error_state;
300 kobj->state = &device->states[i];
301 init_completion(&kobj->kobj_unregister);
302
303 kobj->kobj.parent = &device->kobj;
304 kobj->kobj.ktype = &ktype_state_cpuidle;
305 kobject_set_name(&kobj->kobj, "state%d", i);
306 ret = kobject_register(&kobj->kobj);
307 if (ret) {
308 kfree(kobj);
309 goto error_state;
310 }
311 device->kobjs[i] = kobj;
312 }
313
314 return 0;
315
316error_state:
317 for (i = i - 1; i >= 0; i--)
318 cpuidle_free_state_kobj(device, i);
319 return ret;
320}
321
322/**
323 * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
324 * @device: the target device
325 */
326void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
327{
328 int i;
329
330 for (i = 0; i < device->state_count; i++)
331 cpuidle_free_state_kobj(device, i);
332}
333
334/**
335 * cpuidle_add_sysfs - creates a sysfs instance for the target device
336 * @sysdev: the target device
337 */
338int cpuidle_add_sysfs(struct sys_device *sysdev)
339{
340 int cpu = sysdev->id;
341 struct cpuidle_device *dev;
342
343 dev = per_cpu(cpuidle_devices, cpu);
344 dev->kobj.parent = &sysdev->kobj;
345 dev->kobj.ktype = &ktype_cpuidle;
346 kobject_set_name(&dev->kobj, "%s", "cpuidle");
347 return kobject_register(&dev->kobj);
348}
349
350/**
351 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
352 * @sysdev: the target device
353 */
354void cpuidle_remove_sysfs(struct sys_device *sysdev)
355{
356 int cpu = sysdev->id;
357 struct cpuidle_device *dev;
358
359 dev = per_cpu(cpuidle_devices, cpu);
360 kobject_unregister(&dev->kobj);
361}
diff --git a/drivers/net/wireless/ipw2100.c b/drivers/net/wireless/ipw2100.c
index 8990585bd228..e8a94b746295 100644
--- a/drivers/net/wireless/ipw2100.c
+++ b/drivers/net/wireless/ipw2100.c
@@ -1858,14 +1858,6 @@ static void ipw2100_down(struct ipw2100_priv *priv)
1858 1858
1859 modify_acceptable_latency("ipw2100", INFINITE_LATENCY); 1859 modify_acceptable_latency("ipw2100", INFINITE_LATENCY);
1860 1860
1861#ifdef ACPI_CSTATE_LIMIT_DEFINED
1862 if (priv->config & CFG_C3_DISABLED) {
1863 IPW_DEBUG_INFO(": Resetting C3 transitions.\n");
1864 acpi_set_cstate_limit(priv->cstate_limit);
1865 priv->config &= ~CFG_C3_DISABLED;
1866 }
1867#endif
1868
1869 /* We have to signal any supplicant if we are disassociating */ 1861 /* We have to signal any supplicant if we are disassociating */
1870 if (associated) 1862 if (associated)
1871 wireless_send_event(priv->net_dev, SIOCGIWAP, &wrqu, NULL); 1863 wireless_send_event(priv->net_dev, SIOCGIWAP, &wrqu, NULL);
@@ -2088,14 +2080,6 @@ static void isr_indicate_rf_kill(struct ipw2100_priv *priv, u32 status)
2088 /* RF_KILL is now enabled (else we wouldn't be here) */ 2080 /* RF_KILL is now enabled (else we wouldn't be here) */
2089 priv->status |= STATUS_RF_KILL_HW; 2081 priv->status |= STATUS_RF_KILL_HW;
2090 2082
2091#ifdef ACPI_CSTATE_LIMIT_DEFINED
2092 if (priv->config & CFG_C3_DISABLED) {
2093 IPW_DEBUG_INFO(": Resetting C3 transitions.\n");
2094 acpi_set_cstate_limit(priv->cstate_limit);
2095 priv->config &= ~CFG_C3_DISABLED;
2096 }
2097#endif
2098
2099 /* Make sure the RF Kill check timer is running */ 2083 /* Make sure the RF Kill check timer is running */
2100 priv->stop_rf_kill = 0; 2084 priv->stop_rf_kill = 0;
2101 cancel_delayed_work(&priv->rf_kill); 2085 cancel_delayed_work(&priv->rf_kill);
@@ -2326,23 +2310,10 @@ static void ipw2100_corruption_detected(struct ipw2100_priv *priv, int i)
2326 u32 match, reg; 2310 u32 match, reg;
2327 int j; 2311 int j;
2328#endif 2312#endif
2329#ifdef ACPI_CSTATE_LIMIT_DEFINED
2330 int limit;
2331#endif
2332 2313
2333 IPW_DEBUG_INFO(": PCI latency error detected at 0x%04zX.\n", 2314 IPW_DEBUG_INFO(": PCI latency error detected at 0x%04zX.\n",
2334 i * sizeof(struct ipw2100_status)); 2315 i * sizeof(struct ipw2100_status));
2335 2316
2336#ifdef ACPI_CSTATE_LIMIT_DEFINED
2337 IPW_DEBUG_INFO(": Disabling C3 transitions.\n");
2338 limit = acpi_get_cstate_limit();
2339 if (limit > 2) {
2340 priv->cstate_limit = limit;
2341 acpi_set_cstate_limit(2);
2342 priv->config |= CFG_C3_DISABLED;
2343 }
2344#endif
2345
2346#ifdef IPW2100_DEBUG_C3 2317#ifdef IPW2100_DEBUG_C3
2347 /* Halt the fimrware so we can get a good image */ 2318 /* Halt the fimrware so we can get a good image */
2348 write_register(priv->net_dev, IPW_REG_RESET_REG, 2319 write_register(priv->net_dev, IPW_REG_RESET_REG,
diff --git a/drivers/net/wireless/ipw2100.h b/drivers/net/wireless/ipw2100.h
index de7d384d38af..2b8be2418fa7 100644
--- a/drivers/net/wireless/ipw2100.h
+++ b/drivers/net/wireless/ipw2100.h
@@ -479,7 +479,6 @@ enum {
479#define CFG_ASSOCIATE (1<<6) 479#define CFG_ASSOCIATE (1<<6)
480#define CFG_FIXED_RATE (1<<7) 480#define CFG_FIXED_RATE (1<<7)
481#define CFG_ADHOC_CREATE (1<<8) 481#define CFG_ADHOC_CREATE (1<<8)
482#define CFG_C3_DISABLED (1<<9)
483#define CFG_PASSIVE_SCAN (1<<10) 482#define CFG_PASSIVE_SCAN (1<<10)
484#ifdef CONFIG_IPW2100_MONITOR 483#ifdef CONFIG_IPW2100_MONITOR
485#define CFG_CRC_CHECK (1<<11) 484#define CFG_CRC_CHECK (1<<11)
@@ -508,7 +507,6 @@ struct ipw2100_priv {
508 u8 bssid[ETH_ALEN]; 507 u8 bssid[ETH_ALEN];
509 u8 channel; 508 u8 channel;
510 int last_mode; 509 int last_mode;
511 int cstate_limit;
512 510
513 unsigned long connect_start; 511 unsigned long connect_start;
514 unsigned long last_reset; 512 unsigned long last_reset;
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 99934a999e66..26d79f6db8a0 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -3,6 +3,7 @@
3 3
4#include <linux/kernel.h> 4#include <linux/kernel.h>
5#include <linux/cpu.h> 5#include <linux/cpu.h>
6#include <linux/cpuidle.h>
6 7
7#include <asm/acpi.h> 8#include <asm/acpi.h>
8 9
@@ -75,7 +76,9 @@ struct acpi_processor_cx {
75}; 76};
76 77
77struct acpi_processor_power { 78struct acpi_processor_power {
79 struct cpuidle_device dev;
78 struct acpi_processor_cx *state; 80 struct acpi_processor_cx *state;
81 struct acpi_processor_cx *bm_state;
79 unsigned long bm_check_timestamp; 82 unsigned long bm_check_timestamp;
80 u32 default_state; 83 u32 default_state;
81 u32 bm_activity; 84 u32 bm_activity;
@@ -199,6 +202,7 @@ struct acpi_processor_flags {
199 u8 bm_check:1; 202 u8 bm_check:1;
200 u8 has_cst:1; 203 u8 has_cst:1;
201 u8 power_setup_done:1; 204 u8 power_setup_done:1;
205 u8 bm_rld_set:1;
202}; 206};
203 207
204struct acpi_processor { 208struct acpi_processor {
@@ -322,6 +326,7 @@ int acpi_processor_power_exit(struct acpi_processor *pr,
322 struct acpi_device *device); 326 struct acpi_device *device);
323int acpi_processor_suspend(struct acpi_device * device, pm_message_t state); 327int acpi_processor_suspend(struct acpi_device * device, pm_message_t state);
324int acpi_processor_resume(struct acpi_device * device); 328int acpi_processor_resume(struct acpi_device * device);
329extern struct cpuidle_driver acpi_idle_driver;
325 330
326/* in processor_thermal.c */ 331/* in processor_thermal.c */
327int acpi_processor_get_limit_info(struct acpi_processor *pr); 332int acpi_processor_get_limit_info(struct acpi_processor *pr);
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index bf5e0009de75..8ccedf7a0a5a 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -189,32 +189,6 @@ extern int ec_transaction(u8 command,
189extern int acpi_blacklisted(void); 189extern int acpi_blacklisted(void);
190extern void acpi_bios_year(char *s); 190extern void acpi_bios_year(char *s);
191 191
192#define ACPI_CSTATE_LIMIT_DEFINED /* for driver builds */
193#ifdef CONFIG_ACPI
194
195/*
196 * Set highest legal C-state
197 * 0: C0 okay, but not C1
198 * 1: C1 okay, but not C2
199 * 2: C2 okay, but not C3 etc.
200 */
201
202extern unsigned int max_cstate;
203
204static inline unsigned int acpi_get_cstate_limit(void)
205{
206 return max_cstate;
207}
208static inline void acpi_set_cstate_limit(unsigned int new_limit)
209{
210 max_cstate = new_limit;
211 return;
212}
213#else
214static inline unsigned int acpi_get_cstate_limit(void) { return 0; }
215static inline void acpi_set_cstate_limit(unsigned int new_limit) { return; }
216#endif
217
218#ifdef CONFIG_ACPI_NUMA 192#ifdef CONFIG_ACPI_NUMA
219int acpi_get_pxm(acpi_handle handle); 193int acpi_get_pxm(acpi_handle handle);
220int acpi_get_node(acpi_handle *handle); 194int acpi_get_node(acpi_handle *handle);
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
new file mode 100644
index 000000000000..16a51546db44
--- /dev/null
+++ b/include/linux/cpuidle.h
@@ -0,0 +1,180 @@
1/*
2 * cpuidle.h - a generic framework for CPU idle power management
3 *
4 * (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Shaohua Li <shaohua.li@intel.com>
6 * Adam Belay <abelay@novell.com>
7 *
8 * This code is licenced under the GPL.
9 */
10
11#ifndef _LINUX_CPUIDLE_H
12#define _LINUX_CPUIDLE_H
13
14#include <linux/percpu.h>
15#include <linux/list.h>
16#include <linux/module.h>
17#include <linux/kobject.h>
18#include <linux/completion.h>
19
20#define CPUIDLE_STATE_MAX 8
21#define CPUIDLE_NAME_LEN 16
22
23struct cpuidle_device;
24
25
26/****************************
27 * CPUIDLE DEVICE INTERFACE *
28 ****************************/
29
30struct cpuidle_state {
31 char name[CPUIDLE_NAME_LEN];
32 void *driver_data;
33
34 unsigned int flags;
35 unsigned int exit_latency; /* in US */
36 unsigned int power_usage; /* in mW */
37 unsigned int target_residency; /* in US */
38
39 unsigned int usage;
40 unsigned int time; /* in US */
41
42 int (*enter) (struct cpuidle_device *dev,
43 struct cpuidle_state *state);
44};
45
46/* Idle State Flags */
47#define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
48#define CPUIDLE_FLAG_CHECK_BM (0x02) /* BM activity will exit state */
49#define CPUIDLE_FLAG_SHALLOW (0x10) /* low latency, minimal savings */
50#define CPUIDLE_FLAG_BALANCED (0x20) /* medium latency, moderate savings */
51#define CPUIDLE_FLAG_DEEP (0x40) /* high latency, large savings */
52
53#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
54
55/**
56 * cpuidle_get_statedata - retrieves private driver state data
57 * @state: the state
58 */
59static inline void * cpuidle_get_statedata(struct cpuidle_state *state)
60{
61 return state->driver_data;
62}
63
64/**
65 * cpuidle_set_statedata - stores private driver state data
66 * @state: the state
67 * @data: the private data
68 */
69static inline void
70cpuidle_set_statedata(struct cpuidle_state *state, void *data)
71{
72 state->driver_data = data;
73}
74
75struct cpuidle_state_kobj {
76 struct cpuidle_state *state;
77 struct completion kobj_unregister;
78 struct kobject kobj;
79};
80
81struct cpuidle_device {
82 int enabled:1;
83 unsigned int cpu;
84
85 int last_residency;
86 int state_count;
87 struct cpuidle_state states[CPUIDLE_STATE_MAX];
88 struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
89 struct cpuidle_state *last_state;
90
91 struct list_head device_list;
92 struct kobject kobj;
93 struct completion kobj_unregister;
94 void *governor_data;
95};
96
97DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
98
99/**
100 * cpuidle_get_last_residency - retrieves the last state's residency time
101 * @dev: the target CPU
102 *
103 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
104 */
105static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
106{
107 return dev->last_residency;
108}
109
110
111/****************************
112 * CPUIDLE DRIVER INTERFACE *
113 ****************************/
114
115struct cpuidle_driver {
116 char name[CPUIDLE_NAME_LEN];
117 struct module *owner;
118};
119
120#ifdef CONFIG_CPU_IDLE
121
122extern int cpuidle_register_driver(struct cpuidle_driver *drv);
123extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
124extern int cpuidle_register_device(struct cpuidle_device *dev);
125extern void cpuidle_unregister_device(struct cpuidle_device *dev);
126
127extern void cpuidle_pause_and_lock(void);
128extern void cpuidle_resume_and_unlock(void);
129extern int cpuidle_enable_device(struct cpuidle_device *dev);
130extern void cpuidle_disable_device(struct cpuidle_device *dev);
131
132#else
133
134static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
135{return 0;}
136static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
137static inline int cpuidle_register_device(struct cpuidle_device *dev)
138{return 0;}
139static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
140
141static inline void cpuidle_pause_and_lock(void) { }
142static inline void cpuidle_resume_and_unlock(void) { }
143static inline int cpuidle_enable_device(struct cpuidle_device *dev)
144{return 0;}
145static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
146
147#endif
148
149/******************************
150 * CPUIDLE GOVERNOR INTERFACE *
151 ******************************/
152
153struct cpuidle_governor {
154 char name[CPUIDLE_NAME_LEN];
155 struct list_head governor_list;
156 unsigned int rating;
157
158 int (*enable) (struct cpuidle_device *dev);
159 void (*disable) (struct cpuidle_device *dev);
160
161 int (*select) (struct cpuidle_device *dev);
162 void (*reflect) (struct cpuidle_device *dev);
163
164 struct module *owner;
165};
166
167#ifdef CONFIG_CPU_IDLE
168
169extern int cpuidle_register_governor(struct cpuidle_governor *gov);
170extern void cpuidle_unregister_governor(struct cpuidle_governor *gov);
171
172#else
173
174static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
175{return 0;}
176static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { }
177
178#endif
179
180#endif /* _LINUX_CPUIDLE_H */
diff --git a/include/linux/tick.h b/include/linux/tick.h
index 9a7252e089b9..f4a1395e05ff 100644
--- a/include/linux/tick.h
+++ b/include/linux/tick.h
@@ -40,6 +40,7 @@ enum tick_nohz_mode {
40 * @idle_sleeps: Number of idle calls, where the sched tick was stopped 40 * @idle_sleeps: Number of idle calls, where the sched tick was stopped
41 * @idle_entrytime: Time when the idle call was entered 41 * @idle_entrytime: Time when the idle call was entered
42 * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped 42 * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped
43 * @sleep_length: Duration of the current idle sleep
43 */ 44 */
44struct tick_sched { 45struct tick_sched {
45 struct hrtimer sched_timer; 46 struct hrtimer sched_timer;
@@ -52,6 +53,7 @@ struct tick_sched {
52 unsigned long idle_sleeps; 53 unsigned long idle_sleeps;
53 ktime_t idle_entrytime; 54 ktime_t idle_entrytime;
54 ktime_t idle_sleeptime; 55 ktime_t idle_sleeptime;
56 ktime_t sleep_length;
55 unsigned long last_jiffies; 57 unsigned long last_jiffies;
56 unsigned long next_jiffies; 58 unsigned long next_jiffies;
57 ktime_t idle_expires; 59 ktime_t idle_expires;
@@ -100,10 +102,17 @@ static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
100extern void tick_nohz_stop_sched_tick(void); 102extern void tick_nohz_stop_sched_tick(void);
101extern void tick_nohz_restart_sched_tick(void); 103extern void tick_nohz_restart_sched_tick(void);
102extern void tick_nohz_update_jiffies(void); 104extern void tick_nohz_update_jiffies(void);
105extern ktime_t tick_nohz_get_sleep_length(void);
103# else 106# else
104static inline void tick_nohz_stop_sched_tick(void) { } 107static inline void tick_nohz_stop_sched_tick(void) { }
105static inline void tick_nohz_restart_sched_tick(void) { } 108static inline void tick_nohz_restart_sched_tick(void) { }
106static inline void tick_nohz_update_jiffies(void) { } 109static inline void tick_nohz_update_jiffies(void) { }
110static inline ktime_t tick_nohz_get_sleep_length(void)
111{
112 ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
113
114 return len;
115}
107# endif /* !NO_HZ */ 116# endif /* !NO_HZ */
108 117
109#endif 118#endif
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 8c3fef1db09c..637519af6151 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -153,6 +153,7 @@ void tick_nohz_stop_sched_tick(void)
153 unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags; 153 unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags;
154 struct tick_sched *ts; 154 struct tick_sched *ts;
155 ktime_t last_update, expires, now, delta; 155 ktime_t last_update, expires, now, delta;
156 struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
156 int cpu; 157 int cpu;
157 158
158 local_irq_save(flags); 159 local_irq_save(flags);
@@ -302,11 +303,26 @@ void tick_nohz_stop_sched_tick(void)
302out: 303out:
303 ts->next_jiffies = next_jiffies; 304 ts->next_jiffies = next_jiffies;
304 ts->last_jiffies = last_jiffies; 305 ts->last_jiffies = last_jiffies;
306 ts->sleep_length = ktime_sub(dev->next_event, now);
305end: 307end:
306 local_irq_restore(flags); 308 local_irq_restore(flags);
307} 309}
308 310
309/** 311/**
312 * tick_nohz_get_sleep_length - return the length of the current sleep
313 *
314 * Called from power state control code with interrupts disabled
315 */
316ktime_t tick_nohz_get_sleep_length(void)
317{
318 struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched);
319
320 return ts->sleep_length;
321}
322
323EXPORT_SYMBOL_GPL(tick_nohz_get_sleep_length);
324
325/**
310 * nohz_restart_sched_tick - restart the idle tick from the idle task 326 * nohz_restart_sched_tick - restart the idle tick from the idle task
311 * 327 *
312 * Restart the idle tick when the CPU is woken up from idle 328 * Restart the idle tick when the CPU is woken up from idle
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-07 11:15:19 -0500