summaryrefslogtreecommitdiffstats
path: root/kernel/power
diff options
context:
space:
mode:
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2020-02-12 00:02:30 +0100
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2020-02-13 11:26:27 +0100
commit3a4a0042228a854d9b1073050620820b4a977e6e (patch)
treec577ec4a5d53479cb9cdc7caea6b5150c6827d95 /kernel/power
parent02c92a378940ba1a46b6b7ad277f1b07f8093dbc (diff)
downloadlinux-3a4a0042228a854d9b1073050620820b4a977e6e.tar.gz
linux-3a4a0042228a854d9b1073050620820b4a977e6e.tar.bz2
linux-3a4a0042228a854d9b1073050620820b4a977e6e.zip
PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY notifier chain
Notice that pm_qos_remove_notifier() is not used at all and the only caller of pm_qos_add_notifier() is the cpuidle core, which only needs the PM_QOS_CPU_DMA_LATENCY notifier to invoke wake_up_all_idle_cpus() upon changes of the PM_QOS_CPU_DMA_LATENCY target value. First, to ensure that wake_up_all_idle_cpus() will be called whenever the PM_QOS_CPU_DMA_LATENCY target value changes, modify the pm_qos_add/update/remove_request() family of functions to check if the effective constraint for the PM_QOS_CPU_DMA_LATENCY has changed and call wake_up_all_idle_cpus() directly in that case. Next, drop the PM_QOS_CPU_DMA_LATENCY notifier from cpuidle as it is not necessary any more. Finally, drop both pm_qos_add_notifier() and pm_qos_remove_notifier(), as they have no callers now, along with cpu_dma_lat_notifier which is only used by them. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org> Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Diffstat (limited to 'kernel/power')
-rw-r--r--kernel/power/qos.c47
1 files changed, 11 insertions, 36 deletions
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 952c5f55e23c..201b43bc6457 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -56,14 +56,12 @@
*/
static DEFINE_SPINLOCK(pm_qos_lock);
-static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier);
static struct pm_qos_constraints cpu_dma_constraints = {
.list = PLIST_HEAD_INIT(cpu_dma_constraints.list),
.target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
.default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
.no_constraint_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
.type = PM_QOS_MIN,
- .notifiers = &cpu_dma_lat_notifier,
};
/**
@@ -247,6 +245,14 @@ int pm_qos_request_active(struct pm_qos_request *req)
}
EXPORT_SYMBOL_GPL(pm_qos_request_active);
+static void cpu_latency_qos_update(struct pm_qos_request *req,
+ enum pm_qos_req_action action, s32 value)
+{
+ int ret = pm_qos_update_target(req->qos, &req->node, action, value);
+ if (ret > 0)
+ wake_up_all_idle_cpus();
+}
+
/**
* pm_qos_add_request - inserts new qos request into the list
* @req: pointer to a preallocated handle
@@ -273,7 +279,7 @@ void pm_qos_add_request(struct pm_qos_request *req,
trace_pm_qos_add_request(PM_QOS_CPU_DMA_LATENCY, value);
req->qos = &cpu_dma_constraints;
- pm_qos_update_target(req->qos, &req->node, PM_QOS_ADD_REQ, value);
+ cpu_latency_qos_update(req, PM_QOS_ADD_REQ, value);
}
EXPORT_SYMBOL_GPL(pm_qos_add_request);
@@ -302,7 +308,7 @@ void pm_qos_update_request(struct pm_qos_request *req, s32 new_value)
if (new_value == req->node.prio)
return;
- pm_qos_update_target(req->qos, &req->node, PM_QOS_UPDATE_REQ, new_value);
+ cpu_latency_qos_update(req, PM_QOS_UPDATE_REQ, new_value);
}
EXPORT_SYMBOL_GPL(pm_qos_update_request);
@@ -327,42 +333,11 @@ void pm_qos_remove_request(struct pm_qos_request *req)
trace_pm_qos_remove_request(PM_QOS_CPU_DMA_LATENCY, PM_QOS_DEFAULT_VALUE);
- pm_qos_update_target(req->qos, &req->node, PM_QOS_REMOVE_REQ,
- PM_QOS_DEFAULT_VALUE);
+ cpu_latency_qos_update(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
memset(req, 0, sizeof(*req));
}
EXPORT_SYMBOL_GPL(pm_qos_remove_request);
-/**
- * pm_qos_add_notifier - sets notification entry for changes to target value
- * @pm_qos_class: Ignored.
- * @notifier: notifier block managed by caller.
- *
- * will register the notifier into a notification chain that gets called
- * upon changes to the PM_QOS_CPU_DMA_LATENCY target value.
- */
-int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier)
-{
- return blocking_notifier_chain_register(cpu_dma_constraints.notifiers,
- notifier);
-}
-EXPORT_SYMBOL_GPL(pm_qos_add_notifier);
-
-/**
- * pm_qos_remove_notifier - deletes notification entry from chain.
- * @pm_qos_class: Ignored.
- * @notifier: notifier block to be removed.
- *
- * will remove the notifier from the notification chain that gets called
- * upon changes to the PM_QOS_CPU_DMA_LATENCY target value.
- */
-int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier)
-{
- return blocking_notifier_chain_unregister(cpu_dma_constraints.notifiers,
- notifier);
-}
-EXPORT_SYMBOL_GPL(pm_qos_remove_notifier);
-
/* User space interface to global PM QoS via misc device. */
static int pm_qos_power_open(struct inode *inode, struct file *filp)