diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-power | 45 | ||||
| -rw-r--r-- | Documentation/kernel-parameters.txt | 13 | ||||
| -rw-r--r-- | Documentation/power/states.txt | 60 | ||||
| -rw-r--r-- | kernel/power/main.c | 88 | ||||
| -rw-r--r-- | kernel/power/power.h | 6 | ||||
| -rw-r--r-- | kernel/power/suspend.c | 69 |
6 files changed, 201 insertions, 80 deletions
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index 50b368d490b5..f523e5a3ac33 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -7,30 +7,35 @@ Description: subsystem. What: /sys/power/state -Date: May 2014 +Date: November 2016 Contact: Rafael J. Wysocki <rjw@rjwysocki.net> Description: The /sys/power/state file controls system sleep states. Reading from this file returns the available sleep state - labels, which may be "mem", "standby", "freeze" and "disk" - (hibernation). The meanings of the first three labels depend on - the relative_sleep_states command line argument as follows: - 1) relative_sleep_states = 1 - "mem", "standby", "freeze" represent non-hibernation sleep - states from the deepest ("mem", always present) to the - shallowest ("freeze"). "standby" and "freeze" may or may - not be present depending on the capabilities of the - platform. "freeze" can only be present if "standby" is - present. - 2) relative_sleep_states = 0 (default) - "mem" - "suspend-to-RAM", present if supported. - "standby" - "power-on suspend", present if supported. - "freeze" - "suspend-to-idle", always present. - - Writing to this file one of these strings causes the system to - transition into the corresponding state, if available. See - Documentation/power/states.txt for a description of what - "suspend-to-RAM", "power-on suspend" and "suspend-to-idle" mean. + labels, which may be "mem" (suspend), "standby" (power-on + suspend), "freeze" (suspend-to-idle) and "disk" (hibernation). + + Writing one of the above strings to this file causes the system + to transition into the corresponding state, if available. + + See Documentation/power/states.txt for more information. + +What: /sys/power/mem_sleep +Date: November 2016 +Contact: Rafael J. Wysocki <rjw@rjwysocki.net> +Description: + The /sys/power/mem_sleep file controls the operating mode of + system suspend. Reading from it returns the available modes + as "s2idle" (always present), "shallow" and "deep" (present if + supported). The mode that will be used on subsequent attempts + to suspend the system (by writing "mem" to the /sys/power/state + file described above) is enclosed in square brackets. + + Writing one of the above strings to this file causes the mode + represented by it to be used on subsequent attempts to suspend + the system. + + See Documentation/power/states.txt for more information. What: /sys/power/disk Date: September 2006 diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 37babf91f2cb..4131e169f97a 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2325,6 +2325,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. memory contents and reserves bad memory regions that are detected. + mem_sleep_default= [SUSPEND] Default system suspend mode: + s2idle - Suspend-To-Idle + shallow - Power-On Suspend or equivalent (if supported) + deep - Suspend-To-RAM or equivalent (if supported) + See Documentation/power/states.txt. + meye.*= [HW] Set MotionEye Camera parameters See Documentation/video4linux/meye.txt. @@ -3668,13 +3674,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted. [KNL, SMP] Set scheduler's default relax_domain_level. See Documentation/cgroup-v1/cpusets.txt. - relative_sleep_states= - [SUSPEND] Use sleep state labeling where the deepest - state available other than hibernation is always "mem". - Format: { "0" | "1" } - 0 -- Traditional sleep state labels. - 1 -- Relative sleep state labels. - reserve= [KNL,BUGS] Force the kernel to ignore some iomem area reservetop= [X86-32] diff --git a/Documentation/power/states.txt b/Documentation/power/states.txt index 50f3ef9177c1..008ecb588317 100644 --- a/Documentation/power/states.txt +++ b/Documentation/power/states.txt @@ -8,25 +8,41 @@ for each state. The states are represented by strings that can be read or written to the /sys/power/state file. Those strings may be "mem", "standby", "freeze" and -"disk", where the last one always represents hibernation (Suspend-To-Disk) and -the meaning of the remaining ones depends on the relative_sleep_states command -line argument. - -For relative_sleep_states=1, the strings "mem", "standby" and "freeze" label the -available non-hibernation sleep states from the deepest to the shallowest, -respectively. In that case, "mem" is always present in /sys/power/state, -because there is at least one non-hibernation sleep state in every system. If -the given system supports two non-hibernation sleep states, "standby" is present -in /sys/power/state in addition to "mem". If the system supports three -non-hibernation sleep states, "freeze" will be present in /sys/power/state in -addition to "mem" and "standby". - -For relative_sleep_states=0, which is the default, the following descriptions -apply. - -state: Suspend-To-Idle +"disk", where the last three always represent Power-On Suspend (if supported), +Suspend-To-Idle and hibernation (Suspend-To-Disk), respectively. + +The meaning of the "mem" string is controlled by the /sys/power/mem_sleep file. +It contains strings representing the available modes of system suspend that may +be triggered by writing "mem" to /sys/power/state. These modes are "s2idle" +(Suspend-To-Idle), "shallow" (Power-On Suspend) and "deep" (Suspend-To-RAM). +The "s2idle" mode is always available, while the other ones are only available +if supported by the platform (if not supported, the strings representing them +are not present in /sys/power/mem_sleep). The string representing the suspend +mode to be used subsequently is enclosed in square brackets. Writing one of +the other strings present in /sys/power/mem_sleep to it causes the suspend mode +to be used subsequently to change to the one represented by that string. + +Consequently, there are two ways to cause the system to go into the +Suspend-To-Idle sleep state. The first one is to write "freeze" directly to +/sys/power/state. The second one is to write "s2idle" to /sys/power/mem_sleep +and then to wrtie "mem" to /sys/power/state. Similarly, there are two ways +to cause the system to go into the Power-On Suspend sleep state (the strings to +write to the control files in that case are "standby" or "shallow" and "mem", +respectively) if that state is supported by the platform. In turn, there is +only one way to cause the system to go into the Suspend-To-RAM state (write +"deep" into /sys/power/mem_sleep and "mem" into /sys/power/state). + +The default suspend mode (ie. the one to be used without writing anything into +/sys/power/mem_sleep) is either "deep" (if Suspend-To-RAM is supported) or +"s2idle", but it can be overridden by the value of the "mem_sleep_default" +parameter in the kernel command line. + +The properties of all of the sleep states are described below. + + +State: Suspend-To-Idle ACPI state: S0 -Label: "freeze" +Label: "s2idle" ("freeze") This state is a generic, pure software, light-weight, system sleep state. It allows more energy to be saved relative to runtime idle by freezing user @@ -35,13 +51,13 @@ lower-power than available at run time), such that the processors can spend more time in their idle states. This state can be used for platforms without Power-On Suspend/Suspend-to-RAM -support, or it can be used in addition to Suspend-to-RAM (memory sleep) -to provide reduced resume latency. It is always supported. +support, or it can be used in addition to Suspend-to-RAM to provide reduced +resume latency. It is always supported. State: Standby / Power-On Suspend ACPI State: S1 -Label: "standby" +Label: "shallow" ("standby") This state, if supported, offers moderate, though real, power savings, while providing a relatively low-latency transition back to a working system. No @@ -58,7 +74,7 @@ state. State: Suspend-to-RAM ACPI State: S3 -Label: "mem" +Label: "deep" This state, if supported, offers significant power savings as everything in the system is put into a low-power state, except for memory, which should be placed diff --git a/kernel/power/main.c b/kernel/power/main.c index 281a697fd458..d401c21136d1 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -78,6 +78,78 @@ static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr, power_attr(pm_async); +#ifdef CONFIG_SUSPEND +static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + char *s = buf; + suspend_state_t i; + + for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) + if (mem_sleep_states[i]) { + const char *label = mem_sleep_states[i]; + + if (mem_sleep_current == i) + s += sprintf(s, "[%s] ", label); + else + s += sprintf(s, "%s ", label); + } + + /* Convert the last space to a newline if needed. */ + if (s != buf) + *(s-1) = '\n'; + + return (s - buf); +} + +static suspend_state_t decode_suspend_state(const char *buf, size_t n) +{ + suspend_state_t state; + char *p; + int len; + + p = memchr(buf, '\n', n); + len = p ? p - buf : n; + + for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) { + const char *label = mem_sleep_states[state]; + + if (label && len == strlen(label) && !strncmp(buf, label, len)) + return state; + } + + return PM_SUSPEND_ON; +} + +static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) +{ + suspend_state_t state; + int error; + + error = pm_autosleep_lock(); + if (error) + return error; + + if (pm_autosleep_state() > PM_SUSPEND_ON) { + error = -EBUSY; + goto out; + } + + state = decode_suspend_state(buf, n); + if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON) + mem_sleep_current = state; + else + error = -EINVAL; + + out: + pm_autosleep_unlock(); + return error ? error : n; +} + +power_attr(mem_sleep); +#endif /* CONFIG_SUSPEND */ + #ifdef CONFIG_PM_DEBUG int pm_test_level = TEST_NONE; @@ -368,12 +440,16 @@ static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, } state = decode_state(buf, n); - if (state < PM_SUSPEND_MAX) + if (state < PM_SUSPEND_MAX) { + if (state == PM_SUSPEND_MEM) + state = mem_sleep_current; + error = pm_suspend(state); - else if (state == PM_SUSPEND_MAX) + } else if (state == PM_SUSPEND_MAX) { error = hibernate(); - else + } else { error = -EINVAL; + } out: pm_autosleep_unlock(); @@ -485,6 +561,9 @@ static ssize_t autosleep_store(struct kobject *kobj, && strcmp(buf, "off") && strcmp(buf, "off\n")) return -EINVAL; + if (state == PM_SUSPEND_MEM) + state = mem_sleep_current; + error = pm_autosleep_set_state(state); return error ? error : n; } @@ -602,6 +681,9 @@ static struct attribute * g[] = { #ifdef CONFIG_PM_SLEEP &pm_async_attr.attr, &wakeup_count_attr.attr, +#ifdef CONFIG_SUSPEND + &mem_sleep_attr.attr, +#endif #ifdef CONFIG_PM_AUTOSLEEP &autosleep_attr.attr, #endif diff --git a/kernel/power/power.h b/kernel/power/power.h index 56d1d0dedf76..1dfa0da827d3 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -189,11 +189,15 @@ extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *); #ifdef CONFIG_SUSPEND /* kernel/power/suspend.c */ -extern const char *pm_labels[]; +extern const char * const pm_labels[]; extern const char *pm_states[]; +extern const char *mem_sleep_states[]; +extern suspend_state_t mem_sleep_current; extern int suspend_devices_and_enter(suspend_state_t state); #else /* !CONFIG_SUSPEND */ +#define mem_sleep_current PM_SUSPEND_ON + static inline int suspend_devices_and_enter(suspend_state_t state) { return -ENOSYS; diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 6ccb08f57fcb..15e6baef5c73 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -32,8 +32,21 @@ #include "power.h" -const char *pm_labels[] = { "mem", "standby", "freeze", NULL }; +const char * const pm_labels[] = { + [PM_SUSPEND_FREEZE] = "freeze", + [PM_SUSPEND_STANDBY] = "standby", + [PM_SUSPEND_MEM] = "mem", +}; const char *pm_states[PM_SUSPEND_MAX]; +static const char * const mem_sleep_labels[] = { + [PM_SUSPEND_FREEZE] = "s2idle", + [PM_SUSPEND_STANDBY] = "shallow", + [PM_SUSPEND_MEM] = "deep", +}; +const char *mem_sleep_states[PM_SUSPEND_MAX]; + +suspend_state_t mem_sleep_current = PM_SUSPEND_FREEZE; +static suspend_state_t mem_sleep_default = PM_SUSPEND_MEM; unsigned int pm_suspend_global_flags; EXPORT_SYMBOL_GPL(pm_suspend_global_flags); @@ -110,30 +123,32 @@ static bool valid_state(suspend_state_t state) return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); } -/* - * If this is set, the "mem" label always corresponds to the deepest sleep state - * available, the "standby" label corresponds to the second deepest sleep state - * available (if any), and the "freeze" label corresponds to the remaining - * available sleep state (if there is one). - */ -static bool relative_states; - void __init pm_states_init(void) { + /* "mem" and "freeze" are always present in /sys/power/state. */ + pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM]; + pm_states[PM_SUSPEND_FREEZE] = pm_labels[PM_SUSPEND_FREEZE]; /* - * freeze state should be supported even without any suspend_ops, - * initialize pm_states accordingly here + * Suspend-to-idle should be supported even without any suspend_ops, + * initialize mem_sleep_states[] accordingly here. */ - pm_states[PM_SUSPEND_FREEZE] = pm_labels[relative_states ? 0 : 2]; + mem_sleep_states[PM_SUSPEND_FREEZE] = mem_sleep_labels[PM_SUSPEND_FREEZE]; } -static int __init sleep_states_setup(char *str) +static int __init mem_sleep_default_setup(char *str) { - relative_states = !strncmp(str, "1", 1); + suspend_state_t state; + + for (state = PM_SUSPEND_FREEZE; state <= PM_SUSPEND_MEM; state++) + if (mem_sleep_labels[state] && + !strcmp(str, mem_sleep_labels[state])) { + mem_sleep_default = state; + break; + } + return 1; } - -__setup("relative_sleep_states=", sleep_states_setup); +__setup("mem_sleep_default=", mem_sleep_default_setup); /** * suspend_set_ops - Set the global suspend method table. @@ -141,21 +156,21 @@ __setup("relative_sleep_states=", sleep_states_setup); */ void suspend_set_ops(const struct platform_suspend_ops *ops) { - suspend_state_t i; - int j = 0; - lock_system_sleep(); suspend_ops = ops; - for (i = PM_SUSPEND_MEM; i >= PM_SUSPEND_STANDBY; i--) - if (valid_state(i)) { - pm_states[i] = pm_labels[j++]; - } else if (!relative_states) { - pm_states[i] = NULL; - j++; - } - pm_states[PM_SUSPEND_FREEZE] = pm_labels[j]; + if (valid_state(PM_SUSPEND_STANDBY)) { + mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY]; + pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY]; + if (mem_sleep_default == PM_SUSPEND_STANDBY) + mem_sleep_current = PM_SUSPEND_STANDBY; + } + if (valid_state(PM_SUSPEND_MEM)) { + mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM]; + if (mem_sleep_default == PM_SUSPEND_MEM) + mem_sleep_current = PM_SUSPEND_MEM; + } unlock_system_sleep(); } |