From 20f97caf1120bd02e8ff4adbad3b44b63626feb5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 13 Oct 2017 15:27:24 +0200 Subject: PM / QoS: Drop PM_QOS_FLAG_REMOTE_WAKEUP The PM QoS flag PM_QOS_FLAG_REMOTE_WAKEUP is not used consistently and the vast majority of code simply assumes that remote wakeup should be enabled for devices in runtime suspend if they can generate wakeup signals, so drop it. Signed-off-by: Rafael J. Wysocki Acked-by: Ulf Hansson Reviewed-by: Mika Westerberg --- drivers/base/power/domain.c | 4 +--- drivers/base/power/sysfs.c | 28 ---------------------------- 2 files changed, 1 insertion(+), 31 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index e8ca5e2cf1e5..e6414e9998bb 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -346,9 +346,7 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on, list_for_each_entry(pdd, &genpd->dev_list, list_node) { enum pm_qos_flags_status stat; - stat = dev_pm_qos_flags(pdd->dev, - PM_QOS_FLAG_NO_POWER_OFF - | PM_QOS_FLAG_REMOTE_WAKEUP); + stat = dev_pm_qos_flags(pdd->dev, PM_QOS_FLAG_NO_POWER_OFF); if (stat > PM_QOS_FLAGS_NONE) return -EBUSY; diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c index 156ab57bca77..29bf28fef136 100644 --- a/drivers/base/power/sysfs.c +++ b/drivers/base/power/sysfs.c @@ -309,33 +309,6 @@ static ssize_t pm_qos_no_power_off_store(struct device *dev, static DEVICE_ATTR(pm_qos_no_power_off, 0644, pm_qos_no_power_off_show, pm_qos_no_power_off_store); -static ssize_t pm_qos_remote_wakeup_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev) - & PM_QOS_FLAG_REMOTE_WAKEUP)); -} - -static ssize_t pm_qos_remote_wakeup_store(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t n) -{ - int ret; - - if (kstrtoint(buf, 0, &ret)) - return -EINVAL; - - if (ret != 0 && ret != 1) - return -EINVAL; - - ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP, ret); - return ret < 0 ? ret : n; -} - -static DEVICE_ATTR(pm_qos_remote_wakeup, 0644, - pm_qos_remote_wakeup_show, pm_qos_remote_wakeup_store); - #ifdef CONFIG_PM_SLEEP static const char _enabled[] = "enabled"; static const char _disabled[] = "disabled"; @@ -671,7 +644,6 @@ static const struct attribute_group pm_qos_latency_tolerance_attr_group = { static struct attribute *pm_qos_flags_attrs[] = { &dev_attr_pm_qos_no_power_off.attr, - &dev_attr_pm_qos_remote_wakeup.attr, NULL, }; static const struct attribute_group pm_qos_flags_attr_group = { -- cgit v1.2.3 From 0759e80b84e34a84e7e46e2b1adb528c83d84a47 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 7 Nov 2017 11:33:49 +0100 Subject: PM / QoS: Fix device resume latency framework The special value of 0 for device resume latency PM QoS means "no restriction", but there are two problems with that. First, device resume latency PM QoS requests with 0 as the value are always put in front of requests with positive values in the priority lists used internally by the PM QoS framework, causing 0 to be chosen as an effective constraint value. However, that 0 is then interpreted as "no restriction" effectively overriding the other requests with specific restrictions which is incorrect. Second, the users of device resume latency PM QoS have no way to specify that *any* resume latency at all should be avoided, which is an artificial limitation in general. To address these issues, modify device resume latency PM QoS to use S32_MAX as the "no constraint" value and 0 as the "no latency at all" one and rework its users (the cpuidle menu governor, the genpd QoS governor and the runtime PM framework) to follow these changes. Also add a special "n/a" value to the corresponding user space I/F to allow user space to indicate that it cannot accept any resume latencies at all for the given device. Fixes: 85dc0b8a4019 (PM / QoS: Make it possible to expose PM QoS latency constraints) Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323 Reported-by: Reinette Chatre Signed-off-by: Rafael J. Wysocki Tested-by: Reinette Chatre Tested-by: Geert Uytterhoeven Tested-by: Tero Kristo Reviewed-by: Ramesh Thomas --- drivers/base/power/domain.c | 2 +- drivers/base/power/domain_governor.c | 40 +++++++++++++++--------------------- drivers/base/power/qos.c | 5 ++++- drivers/base/power/runtime.c | 2 +- drivers/base/power/sysfs.c | 25 ++++++++++++++++++---- 5 files changed, 43 insertions(+), 31 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 679c79545e42..24e39ce27bd8 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1326,7 +1326,7 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev, gpd_data->base.dev = dev; gpd_data->td.constraint_changed = true; - gpd_data->td.effective_constraint_ns = 0; + gpd_data->td.effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS; gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier; spin_lock_irq(&dev->power.lock); diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c index e4cca8adab32..99896fbf18e4 100644 --- a/drivers/base/power/domain_governor.c +++ b/drivers/base/power/domain_governor.c @@ -33,15 +33,10 @@ static int dev_update_qos_constraint(struct device *dev, void *data) * known at this point anyway). */ constraint_ns = dev_pm_qos_read_value(dev); - if (constraint_ns > 0) - constraint_ns *= NSEC_PER_USEC; + constraint_ns *= NSEC_PER_USEC; } - /* 0 means "no constraint" */ - if (constraint_ns == 0) - return 0; - - if (constraint_ns < *constraint_ns_p || *constraint_ns_p == 0) + if (constraint_ns < *constraint_ns_p) *constraint_ns_p = constraint_ns; return 0; @@ -69,12 +64,12 @@ static bool default_suspend_ok(struct device *dev) } td->constraint_changed = false; td->cached_suspend_ok = false; - td->effective_constraint_ns = -1; + td->effective_constraint_ns = 0; constraint_ns = __dev_pm_qos_read_value(dev); spin_unlock_irqrestore(&dev->power.lock, flags); - if (constraint_ns < 0) + if (constraint_ns == 0) return false; constraint_ns *= NSEC_PER_USEC; @@ -87,25 +82,25 @@ static bool default_suspend_ok(struct device *dev) device_for_each_child(dev, &constraint_ns, dev_update_qos_constraint); - if (constraint_ns == 0) { + if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS) { /* "No restriction", so the device is allowed to suspend. */ - td->effective_constraint_ns = 0; + td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS; td->cached_suspend_ok = true; - } else if (constraint_ns < 0) { + } else if (constraint_ns == 0) { /* * This triggers if one of the children that don't belong to a - * domain has a negative PM QoS constraint and it's better not - * to suspend then. effective_constraint_ns is negative already - * and cached_suspend_ok is false, so bail out. + * domain has a zero PM QoS constraint and it's better not to + * suspend then. effective_constraint_ns is zero already and + * cached_suspend_ok is false, so bail out. */ return false; } else { constraint_ns -= td->suspend_latency_ns + td->resume_latency_ns; /* - * effective_constraint_ns is negative already and - * cached_suspend_ok is false, so if the computed value is not - * positive, return right away. + * effective_constraint_ns is zero already and cached_suspend_ok + * is false, so if the computed value is not positive, return + * right away. */ if (constraint_ns <= 0) return false; @@ -174,13 +169,10 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd, td = &to_gpd_data(pdd)->td; constraint_ns = td->effective_constraint_ns; /* - * Negative values mean "no suspend at all" and this runs only - * when all devices in the domain are suspended, so it must be - * 0 at least. - * - * 0 means "no constraint" + * Zero means "no suspend at all" and this runs only when all + * devices in the domain are suspended, so it must be positive. */ - if (constraint_ns == 0) + if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS) continue; if (constraint_ns <= off_on_time_ns) diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c index 277d43a83f53..3382542b39b7 100644 --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -139,6 +139,9 @@ static int apply_constraint(struct dev_pm_qos_request *req, switch(req->type) { case DEV_PM_QOS_RESUME_LATENCY: + if (WARN_ON(action != PM_QOS_REMOVE_REQ && value < 0)) + value = 0; + ret = pm_qos_update_target(&qos->resume_latency, &req->data.pnode, action, value); break; @@ -189,7 +192,7 @@ static int dev_pm_qos_constraints_allocate(struct device *dev) plist_head_init(&c->list); c->target_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; c->default_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; - c->no_constraint_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; + c->no_constraint_value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; c->type = PM_QOS_MIN; c->notifiers = n; diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 7bcf80fa9ada..13e015905543 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -253,7 +253,7 @@ static int rpm_check_suspend_allowed(struct device *dev) || (dev->power.request_pending && dev->power.request == RPM_REQ_RESUME)) retval = -EAGAIN; - else if (__dev_pm_qos_read_value(dev) < 0) + else if (__dev_pm_qos_read_value(dev) == 0) retval = -EPERM; else if (dev->power.runtime_status == RPM_SUSPENDED) retval = 1; diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c index 29bf28fef136..e153e28b1857 100644 --- a/drivers/base/power/sysfs.c +++ b/drivers/base/power/sysfs.c @@ -218,7 +218,14 @@ static ssize_t pm_qos_resume_latency_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", dev_pm_qos_requested_resume_latency(dev)); + s32 value = dev_pm_qos_requested_resume_latency(dev); + + if (value == 0) + return sprintf(buf, "n/a\n"); + else if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT) + value = 0; + + return sprintf(buf, "%d\n", value); } static ssize_t pm_qos_resume_latency_store(struct device *dev, @@ -228,11 +235,21 @@ static ssize_t pm_qos_resume_latency_store(struct device *dev, s32 value; int ret; - if (kstrtos32(buf, 0, &value)) - return -EINVAL; + if (!kstrtos32(buf, 0, &value)) { + /* + * Prevent users from writing negative or "no constraint" values + * directly. + */ + if (value < 0 || value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT) + return -EINVAL; - if (value < 0) + if (value == 0) + value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; + } else if (!strcmp(buf, "n/a") || !strcmp(buf, "n/a\n")) { + value = 0; + } else { return -EINVAL; + } ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req, value); -- cgit v1.2.3