Merge branch 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6

* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
  x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param
  x86 idle: deprecate "no-hlt" cmdline param
  x86 idle APM: deprecate CONFIG_APM_CPU_IDLE
  x86 idle floppy: deprecate disable_hlt()
  x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it
  x86 idle: clarify AMD erratum 400 workaround
  idle governor: Avoid lock acquisition to read pm_qos before entering idle
  cpuidle: menu: fixed wrapping timers at 4.294 seconds
This commit is contained in:
Linus Torvalds 2011-05-29 11:18:09 -07:00
commit f310642123
14 changed files with 102 additions and 40 deletions

View file

@ -6,6 +6,42 @@ be removed from this file.
---------------------------
What: x86 floppy disable_hlt
When: 2012
Why: ancient workaround of dubious utility clutters the
code used by everybody else.
Who: Len Brown <len.brown@intel.com>
---------------------------
What: CONFIG_APM_CPU_IDLE, and its ability to call APM BIOS in idle
When: 2012
Why: This optional sub-feature of APM is of dubious reliability,
and ancient APM laptops are likely better served by calling HLT.
Deleting CONFIG_APM_CPU_IDLE allows x86 to stop exporting
the pm_idle function pointer to modules.
Who: Len Brown <len.brown@intel.com>
----------------------------
What: x86_32 "no-hlt" cmdline param
When: 2012
Why: remove a branch from idle path, simplify code used by everybody.
This option disabled the use of HLT in idle and machine_halt()
for hardware that was flakey 15-years ago. Today we have
"idle=poll" that removed HLT from idle, and so if such a machine
is still running the upstream kernel, "idle=poll" is likely sufficient.
Who: Len Brown <len.brown@intel.com>
----------------------------
What: x86 "idle=mwait" cmdline param
When: 2012
Why: simplify x86 idle code
Who: Len Brown <len.brown@intel.com>
----------------------------
What: PRISM54
When: 2.6.34

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@ -139,7 +139,7 @@ static inline unsigned int acpi_processor_cstate_check(unsigned int max_cstate)
boot_cpu_data.x86_model <= 0x05 &&
boot_cpu_data.x86_mask < 0x0A)
return 1;
else if (c1e_detected)
else if (amd_e400_c1e_detected)
return 1;
else
return max_cstate;

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@ -16,6 +16,6 @@ static inline void enter_idle(void) { }
static inline void exit_idle(void) { }
#endif /* CONFIG_X86_64 */
void c1e_remove_cpu(int cpu);
void amd_e400_remove_cpu(int cpu);
#endif /* _ASM_X86_IDLE_H */

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@ -754,10 +754,10 @@ static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx);
extern void select_idle_routine(const struct cpuinfo_x86 *c);
extern void init_c1e_mask(void);
extern void init_amd_e400_c1e_mask(void);
extern unsigned long boot_option_idle_override;
extern bool c1e_detected;
extern bool amd_e400_c1e_detected;
enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
IDLE_POLL, IDLE_FORCE_MWAIT};

View file

@ -361,6 +361,7 @@ struct apm_user {
* idle percentage above which bios idle calls are done
*/
#ifdef CONFIG_APM_CPU_IDLE
#warning deprecated CONFIG_APM_CPU_IDLE will be deleted in 2012
#define DEFAULT_IDLE_THRESHOLD 95
#else
#define DEFAULT_IDLE_THRESHOLD 100
@ -904,6 +905,7 @@ static void apm_cpu_idle(void)
unsigned int jiffies_since_last_check = jiffies - last_jiffies;
unsigned int bucket;
WARN_ONCE(1, "deprecated apm_cpu_idle will be deleted in 2012");
recalc:
if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
use_apm_idle = 0;

View file

@ -19,6 +19,7 @@
static int __init no_halt(char *s)
{
WARN_ONCE(1, "\"no-hlt\" is deprecated, please use \"idle=poll\"\n");
boot_cpu_data.hlt_works_ok = 0;
return 1;
}

View file

@ -902,7 +902,7 @@ static void vgetcpu_set_mode(void)
void __init identify_boot_cpu(void)
{
identify_cpu(&boot_cpu_data);
init_c1e_mask();
init_amd_e400_c1e_mask();
#ifdef CONFIG_X86_32
sysenter_setup();
enable_sep_cpu();

View file

@ -337,7 +337,9 @@ EXPORT_SYMBOL(boot_option_idle_override);
* Powermanagement idle function, if any..
*/
void (*pm_idle)(void);
#if defined(CONFIG_APM_MODULE) && defined(CONFIG_APM_CPU_IDLE)
EXPORT_SYMBOL(pm_idle);
#endif
#ifdef CONFIG_X86_32
/*
@ -397,7 +399,7 @@ void default_idle(void)
cpu_relax();
}
}
#ifdef CONFIG_APM_MODULE
#if defined(CONFIG_APM_MODULE) && defined(CONFIG_APM_CPU_IDLE)
EXPORT_SYMBOL(default_idle);
#endif
@ -535,45 +537,45 @@ int mwait_usable(const struct cpuinfo_x86 *c)
return (edx & MWAIT_EDX_C1);
}
bool c1e_detected;
EXPORT_SYMBOL(c1e_detected);
bool amd_e400_c1e_detected;
EXPORT_SYMBOL(amd_e400_c1e_detected);
static cpumask_var_t c1e_mask;
static cpumask_var_t amd_e400_c1e_mask;
void c1e_remove_cpu(int cpu)
void amd_e400_remove_cpu(int cpu)
{
if (c1e_mask != NULL)
cpumask_clear_cpu(cpu, c1e_mask);
if (amd_e400_c1e_mask != NULL)
cpumask_clear_cpu(cpu, amd_e400_c1e_mask);
}
/*
* C1E aware idle routine. We check for C1E active in the interrupt
* AMD Erratum 400 aware idle routine. We check for C1E active in the interrupt
* pending message MSR. If we detect C1E, then we handle it the same
* way as C3 power states (local apic timer and TSC stop)
*/
static void c1e_idle(void)
static void amd_e400_idle(void)
{
if (need_resched())
return;
if (!c1e_detected) {
if (!amd_e400_c1e_detected) {
u32 lo, hi;
rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi);
if (lo & K8_INTP_C1E_ACTIVE_MASK) {
c1e_detected = true;
amd_e400_c1e_detected = true;
if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
mark_tsc_unstable("TSC halt in AMD C1E");
printk(KERN_INFO "System has AMD C1E enabled\n");
}
}
if (c1e_detected) {
if (amd_e400_c1e_detected) {
int cpu = smp_processor_id();
if (!cpumask_test_cpu(cpu, c1e_mask)) {
cpumask_set_cpu(cpu, c1e_mask);
if (!cpumask_test_cpu(cpu, amd_e400_c1e_mask)) {
cpumask_set_cpu(cpu, amd_e400_c1e_mask);
/*
* Force broadcast so ACPI can not interfere.
*/
@ -616,17 +618,17 @@ void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
pm_idle = mwait_idle;
} else if (cpu_has_amd_erratum(amd_erratum_400)) {
/* E400: APIC timer interrupt does not wake up CPU from C1e */
printk(KERN_INFO "using C1E aware idle routine\n");
pm_idle = c1e_idle;
printk(KERN_INFO "using AMD E400 aware idle routine\n");
pm_idle = amd_e400_idle;
} else
pm_idle = default_idle;
}
void __init init_c1e_mask(void)
void __init init_amd_e400_c1e_mask(void)
{
/* If we're using c1e_idle, we need to allocate c1e_mask. */
if (pm_idle == c1e_idle)
zalloc_cpumask_var(&c1e_mask, GFP_KERNEL);
/* If we're using amd_e400_idle, we need to allocate amd_e400_c1e_mask. */
if (pm_idle == amd_e400_idle)
zalloc_cpumask_var(&amd_e400_c1e_mask, GFP_KERNEL);
}
static int __init idle_setup(char *str)
@ -640,6 +642,7 @@ static int __init idle_setup(char *str)
boot_option_idle_override = IDLE_POLL;
} else if (!strcmp(str, "mwait")) {
boot_option_idle_override = IDLE_FORCE_MWAIT;
WARN_ONCE(1, "\idle=mwait\" will be removed in 2012\"\n");
} else if (!strcmp(str, "halt")) {
/*
* When the boot option of idle=halt is added, halt is

View file

@ -1307,7 +1307,7 @@ void play_dead_common(void)
{
idle_task_exit();
reset_lazy_tlbstate();
c1e_remove_cpu(raw_smp_processor_id());
amd_e400_remove_cpu(raw_smp_processor_id());
mb();
/* Ack it */

View file

@ -161,7 +161,7 @@ static void lapic_timer_check_state(int state, struct acpi_processor *pr,
if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT))
return;
if (c1e_detected)
if (amd_e400_c1e_detected)
type = ACPI_STATE_C1;
/*

View file

@ -1038,6 +1038,7 @@ static void floppy_disable_hlt(void)
{
unsigned long flags;
WARN_ONCE(1, "floppy_disable_hlt() scheduled for removal in 2012");
spin_lock_irqsave(&floppy_hlt_lock, flags);
if (!hlt_disabled) {
hlt_disabled = 1;

View file

@ -237,6 +237,7 @@ static int menu_select(struct cpuidle_device *dev)
unsigned int power_usage = -1;
int i;
int multiplier;
struct timespec t;
if (data->needs_update) {
menu_update(dev);
@ -251,8 +252,9 @@ static int menu_select(struct cpuidle_device *dev)
return 0;
/* determine the expected residency time, round up */
t = ktime_to_timespec(tick_nohz_get_sleep_length());
data->expected_us =
DIV_ROUND_UP((u32)ktime_to_ns(tick_nohz_get_sleep_length()), 1000);
t.tv_sec * USEC_PER_SEC + t.tv_nsec / NSEC_PER_USEC;
data->bucket = which_bucket(data->expected_us);

View file

@ -16,6 +16,10 @@
#define PM_QOS_NUM_CLASSES 4
#define PM_QOS_DEFAULT_VALUE -1
#define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC)
#define PM_QOS_NETWORK_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC)
#define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0
struct pm_qos_request_list {
struct plist_node list;
int pm_qos_class;

View file

@ -54,11 +54,17 @@ enum pm_qos_type {
PM_QOS_MIN /* return the smallest value */
};
/*
* Note: The lockless read path depends on the CPU accessing
* target_value atomically. Atomic access is only guaranteed on all CPU
* types linux supports for 32 bit quantites
*/
struct pm_qos_object {
struct plist_head requests;
struct blocking_notifier_head *notifiers;
struct miscdevice pm_qos_power_miscdev;
char *name;
s32 target_value; /* Do not change to 64 bit */
s32 default_value;
enum pm_qos_type type;
};
@ -71,7 +77,8 @@ static struct pm_qos_object cpu_dma_pm_qos = {
.requests = PLIST_HEAD_INIT(cpu_dma_pm_qos.requests, pm_qos_lock),
.notifiers = &cpu_dma_lat_notifier,
.name = "cpu_dma_latency",
.default_value = 2000 * USEC_PER_SEC,
.target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
.default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
.type = PM_QOS_MIN,
};
@ -80,7 +87,8 @@ static struct pm_qos_object network_lat_pm_qos = {
.requests = PLIST_HEAD_INIT(network_lat_pm_qos.requests, pm_qos_lock),
.notifiers = &network_lat_notifier,
.name = "network_latency",
.default_value = 2000 * USEC_PER_SEC,
.target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
.default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
.type = PM_QOS_MIN
};
@ -90,7 +98,8 @@ static struct pm_qos_object network_throughput_pm_qos = {
.requests = PLIST_HEAD_INIT(network_throughput_pm_qos.requests, pm_qos_lock),
.notifiers = &network_throughput_notifier,
.name = "network_throughput",
.default_value = 0,
.target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
.default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
.type = PM_QOS_MAX,
};
@ -136,6 +145,16 @@ static inline int pm_qos_get_value(struct pm_qos_object *o)
}
}
static inline s32 pm_qos_read_value(struct pm_qos_object *o)
{
return o->target_value;
}
static inline void pm_qos_set_value(struct pm_qos_object *o, s32 value)
{
o->target_value = value;
}
static void update_target(struct pm_qos_object *o, struct plist_node *node,
int del, int value)
{
@ -160,6 +179,7 @@ static void update_target(struct pm_qos_object *o, struct plist_node *node,
plist_add(node, &o->requests);
}
curr_value = pm_qos_get_value(o);
pm_qos_set_value(o, curr_value);
spin_unlock_irqrestore(&pm_qos_lock, flags);
if (prev_value != curr_value)
@ -194,18 +214,11 @@ static int find_pm_qos_object_by_minor(int minor)
* pm_qos_request - returns current system wide qos expectation
* @pm_qos_class: identification of which qos value is requested
*
* This function returns the current target value in an atomic manner.
* This function returns the current target value.
*/
int pm_qos_request(int pm_qos_class)
{
unsigned long flags;
int value;
spin_lock_irqsave(&pm_qos_lock, flags);
value = pm_qos_get_value(pm_qos_array[pm_qos_class]);
spin_unlock_irqrestore(&pm_qos_lock, flags);
return value;
return pm_qos_read_value(pm_qos_array[pm_qos_class]);
}
EXPORT_SYMBOL_GPL(pm_qos_request);