Commit 8d87ae48 authored by Kees Cook's avatar Kees Cook Committed by Rafael J. Wysocki
Browse files

PM: domains: Fix up terminology with parent/child 

The genpd infrastructure uses the terms master/slave, but such uses have
no external exposures (not even in Documentation/driver-api/pm/*) and are
not mandated by nor associated with any external specifications. Change
the language used through-out to parent/child.

There was one possible exception in the debugfs node
"pm_genpd/pm_genpd_summary" but its path has no hits outside of the
kernel itself when performing a code search[1], and it seems even this
single usage has been non-functional since it was introduced due to a
typo in the Python ("apend" instead of correct "append"). Fix the typo
while we're at it.

Link: https://codesearch.debian.net/

 # [1]
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: default avatarKieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent dcb7fd82

drivers/base/power/domain.c

+97 −97
Original line number Diff line number Diff line
@@ -263,18 +263,18 @@ static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd, 
	/*

	 * Traverse all sub-domains within the domain. This can be

	 * done without any additional locking as the link->performance_state

	 * field is protected by the master genpd->lock, which is already taken.

	 * field is protected by the parent genpd->lock, which is already taken.

	 *

	 * Also note that link->performance_state (subdomain's performance state

	 * requirement to master domain) is different from

	 * link->slave->performance_state (current performance state requirement

	 * requirement to parent domain) is different from

	 * link->child->performance_state (current performance state requirement

	 * of the devices/sub-domains of the subdomain) and so can have a

	 * different value.

	 *

	 * Note that we also take vote from powered-off sub-domains into account

	 * as the same is done for devices right now.

	 */

	list_for_each_entry(link, &genpd->master_links, master_node) {

	list_for_each_entry(link, &genpd->parent_links, parent_node) {

		if (link->performance_state > state)

			state = link->performance_state;

	}
@@ -285,40 +285,40 @@ static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd, 
static int _genpd_set_performance_state(struct generic_pm_domain *genpd,

					unsigned int state, int depth)

{

	struct generic_pm_domain *master;

	struct generic_pm_domain *parent;

	struct gpd_link *link;

	int master_state, ret;

	int parent_state, ret;



	if (state == genpd->performance_state)

		return 0;



	/* Propagate to masters of genpd */

	list_for_each_entry(link, &genpd->slave_links, slave_node) {

		master = link->master;

	/* Propagate to parents of genpd */

	list_for_each_entry(link, &genpd->child_links, child_node) {

		parent = link->parent;



		if (!master->set_performance_state)

		if (!parent->set_performance_state)

			continue;



		/* Find master's performance state */

		/* Find parent's performance state */

		ret = dev_pm_opp_xlate_performance_state(genpd->opp_table,

							 master->opp_table,

							 parent->opp_table,

							 state);

		if (unlikely(ret < 0))

			goto err;



		master_state = ret;

		parent_state = ret;



		genpd_lock_nested(master, depth + 1);

		genpd_lock_nested(parent, depth + 1);



		link->prev_performance_state = link->performance_state;

		link->performance_state = master_state;

		master_state = _genpd_reeval_performance_state(master,

						master_state);

		ret = _genpd_set_performance_state(master, master_state, depth + 1);

		link->performance_state = parent_state;

		parent_state = _genpd_reeval_performance_state(parent,

						parent_state);

		ret = _genpd_set_performance_state(parent, parent_state, depth + 1);

		if (ret)

			link->performance_state = link->prev_performance_state;



		genpd_unlock(master);

		genpd_unlock(parent);



		if (ret)

			goto err;
@@ -333,26 +333,26 @@ static int _genpd_set_performance_state(struct generic_pm_domain *genpd, 


err:

	/* Encountered an error, lets rollback */

	list_for_each_entry_continue_reverse(link, &genpd->slave_links,

					     slave_node) {

		master = link->master;

	list_for_each_entry_continue_reverse(link, &genpd->child_links,

					     child_node) {

		parent = link->parent;



		if (!master->set_performance_state)

		if (!parent->set_performance_state)

			continue;



		genpd_lock_nested(master, depth + 1);

		genpd_lock_nested(parent, depth + 1);



		master_state = link->prev_performance_state;

		link->performance_state = master_state;

		parent_state = link->prev_performance_state;

		link->performance_state = parent_state;



		master_state = _genpd_reeval_performance_state(master,

						master_state);

		if (_genpd_set_performance_state(master, master_state, depth + 1)) {

		parent_state = _genpd_reeval_performance_state(parent,

						parent_state);

		if (_genpd_set_performance_state(parent, parent_state, depth + 1)) {

			pr_err("%s: Failed to roll back to %d performance state\n",

			       master->name, master_state);

			       parent->name, parent_state);

		}



		genpd_unlock(master);

		genpd_unlock(parent);

	}



	return ret;
@@ -552,7 +552,7 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on, 


		/*

		 * If sd_count > 0 at this point, one of the subdomains hasn't

		 * managed to call genpd_power_on() for the master yet after

		 * managed to call genpd_power_on() for the parent yet after

		 * incrementing it.  In that case genpd_power_on() will wait

		 * for us to drop the lock, so we can call .power_off() and let

		 * the genpd_power_on() restore power for us (this shouldn't
@@ -566,22 +566,22 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on, 
	genpd->status = GPD_STATE_POWER_OFF;

	genpd_update_accounting(genpd);



	list_for_each_entry(link, &genpd->slave_links, slave_node) {

		genpd_sd_counter_dec(link->master);

		genpd_lock_nested(link->master, depth + 1);

		genpd_power_off(link->master, false, depth + 1);

		genpd_unlock(link->master);

	list_for_each_entry(link, &genpd->child_links, child_node) {

		genpd_sd_counter_dec(link->parent);

		genpd_lock_nested(link->parent, depth + 1);

		genpd_power_off(link->parent, false, depth + 1);

		genpd_unlock(link->parent);

	}



	return 0;

}



/**

 * genpd_power_on - Restore power to a given PM domain and its masters.

 * genpd_power_on - Restore power to a given PM domain and its parents.

 * @genpd: PM domain to power up.

 * @depth: nesting count for lockdep.

 *

 * Restore power to @genpd and all of its masters so that it is possible to

 * Restore power to @genpd and all of its parents so that it is possible to

 * resume a device belonging to it.

 */

static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
@@ -594,20 +594,20 @@ static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth) 


	/*

	 * The list is guaranteed not to change while the loop below is being

	 * executed, unless one of the masters' .power_on() callbacks fiddles

	 * executed, unless one of the parents' .power_on() callbacks fiddles

	 * with it.

	 */

	list_for_each_entry(link, &genpd->slave_links, slave_node) {

		struct generic_pm_domain *master = link->master;

	list_for_each_entry(link, &genpd->child_links, child_node) {

		struct generic_pm_domain *parent = link->parent;



		genpd_sd_counter_inc(master);

		genpd_sd_counter_inc(parent);



		genpd_lock_nested(master, depth + 1);

		ret = genpd_power_on(master, depth + 1);

		genpd_unlock(master);

		genpd_lock_nested(parent, depth + 1);

		ret = genpd_power_on(parent, depth + 1);

		genpd_unlock(parent);



		if (ret) {

			genpd_sd_counter_dec(master);

			genpd_sd_counter_dec(parent);

			goto err;

		}

	}
@@ -623,12 +623,12 @@ static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth) 


 err:

	list_for_each_entry_continue_reverse(link,

					&genpd->slave_links,

					slave_node) {

		genpd_sd_counter_dec(link->master);

		genpd_lock_nested(link->master, depth + 1);

		genpd_power_off(link->master, false, depth + 1);

		genpd_unlock(link->master);

					&genpd->child_links,

					child_node) {

		genpd_sd_counter_dec(link->parent);

		genpd_lock_nested(link->parent, depth + 1);

		genpd_power_off(link->parent, false, depth + 1);

		genpd_unlock(link->parent);

	}



	return ret;
@@ -932,13 +932,13 @@ late_initcall(genpd_power_off_unused); 
#ifdef CONFIG_PM_SLEEP



/**

 * genpd_sync_power_off - Synchronously power off a PM domain and its masters.

 * genpd_sync_power_off - Synchronously power off a PM domain and its parents.

 * @genpd: PM domain to power off, if possible.

 * @use_lock: use the lock.

 * @depth: nesting count for lockdep.

 *

 * Check if the given PM domain can be powered off (during system suspend or

 * hibernation) and do that if so.  Also, in that case propagate to its masters.

 * hibernation) and do that if so.  Also, in that case propagate to its parents.

 *

 * This function is only called in "noirq" and "syscore" stages of system power

 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
@@ -963,21 +963,21 @@ static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock, 


	genpd->status = GPD_STATE_POWER_OFF;



	list_for_each_entry(link, &genpd->slave_links, slave_node) {

		genpd_sd_counter_dec(link->master);

	list_for_each_entry(link, &genpd->child_links, child_node) {

		genpd_sd_counter_dec(link->parent);



		if (use_lock)

			genpd_lock_nested(link->master, depth + 1);

			genpd_lock_nested(link->parent, depth + 1);



		genpd_sync_power_off(link->master, use_lock, depth + 1);

		genpd_sync_power_off(link->parent, use_lock, depth + 1);



		if (use_lock)

			genpd_unlock(link->master);

			genpd_unlock(link->parent);

	}

}



/**

 * genpd_sync_power_on - Synchronously power on a PM domain and its masters.

 * genpd_sync_power_on - Synchronously power on a PM domain and its parents.

 * @genpd: PM domain to power on.

 * @use_lock: use the lock.

 * @depth: nesting count for lockdep.
@@ -994,16 +994,16 @@ static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock, 
	if (genpd_status_on(genpd))

		return;



	list_for_each_entry(link, &genpd->slave_links, slave_node) {

		genpd_sd_counter_inc(link->master);

	list_for_each_entry(link, &genpd->child_links, child_node) {

		genpd_sd_counter_inc(link->parent);



		if (use_lock)

			genpd_lock_nested(link->master, depth + 1);

			genpd_lock_nested(link->parent, depth + 1);



		genpd_sync_power_on(link->master, use_lock, depth + 1);

		genpd_sync_power_on(link->parent, use_lock, depth + 1);



		if (use_lock)

			genpd_unlock(link->master);

			genpd_unlock(link->parent);

	}



	_genpd_power_on(genpd, false);
@@ -1443,12 +1443,12 @@ static void genpd_update_cpumask(struct generic_pm_domain *genpd, 
	if (!genpd_is_cpu_domain(genpd))

		return;



	list_for_each_entry(link, &genpd->slave_links, slave_node) {

		struct generic_pm_domain *master = link->master;

	list_for_each_entry(link, &genpd->child_links, child_node) {

		struct generic_pm_domain *parent = link->parent;



		genpd_lock_nested(master, depth + 1);

		genpd_update_cpumask(master, cpu, set, depth + 1);

		genpd_unlock(master);

		genpd_lock_nested(parent, depth + 1);

		genpd_update_cpumask(parent, cpu, set, depth + 1);

		genpd_unlock(parent);

	}



	if (set)
@@ -1636,17 +1636,17 @@ static int genpd_add_subdomain(struct generic_pm_domain *genpd, 
		goto out;

	}



	list_for_each_entry(itr, &genpd->master_links, master_node) {

		if (itr->slave == subdomain && itr->master == genpd) {

	list_for_each_entry(itr, &genpd->parent_links, parent_node) {

		if (itr->child == subdomain && itr->parent == genpd) {

			ret = -EINVAL;

			goto out;

		}

	}



	link->master = genpd;

	list_add_tail(&link->master_node, &genpd->master_links);

	link->slave = subdomain;

	list_add_tail(&link->slave_node, &subdomain->slave_links);

	link->parent = genpd;

	list_add_tail(&link->parent_node, &genpd->parent_links);

	link->child = subdomain;

	list_add_tail(&link->child_node, &subdomain->child_links);

	if (genpd_status_on(subdomain))

		genpd_sd_counter_inc(genpd);
@@ -1660,7 +1660,7 @@ static int genpd_add_subdomain(struct generic_pm_domain *genpd, 


/**

 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.

 * @genpd: Master PM domain to add the subdomain to.

 * @genpd: Leader PM domain to add the subdomain to.

 * @subdomain: Subdomain to be added.

 */

int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
@@ -1678,7 +1678,7 @@ EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain); 


/**

 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.

 * @genpd: Master PM domain to remove the subdomain from.

 * @genpd: Leader PM domain to remove the subdomain from.

 * @subdomain: Subdomain to be removed.

 */

int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
@@ -1693,19 +1693,19 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, 
	genpd_lock(subdomain);

	genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);



	if (!list_empty(&subdomain->master_links) || subdomain->device_count) {

	if (!list_empty(&subdomain->parent_links) || subdomain->device_count) {

		pr_warn("%s: unable to remove subdomain %s\n",

			genpd->name, subdomain->name);

		ret = -EBUSY;

		goto out;

	}



	list_for_each_entry_safe(link, l, &genpd->master_links, master_node) {

		if (link->slave != subdomain)

	list_for_each_entry_safe(link, l, &genpd->parent_links, parent_node) {

		if (link->child != subdomain)

			continue;



		list_del(&link->master_node);

		list_del(&link->slave_node);

		list_del(&link->parent_node);

		list_del(&link->child_node);

		kfree(link);

		if (genpd_status_on(subdomain))

			genpd_sd_counter_dec(genpd);
@@ -1770,8 +1770,8 @@ int pm_genpd_init(struct generic_pm_domain *genpd, 
	if (IS_ERR_OR_NULL(genpd))

		return -EINVAL;



	INIT_LIST_HEAD(&genpd->master_links);

	INIT_LIST_HEAD(&genpd->slave_links);

	INIT_LIST_HEAD(&genpd->parent_links);

	INIT_LIST_HEAD(&genpd->child_links);

	INIT_LIST_HEAD(&genpd->dev_list);

	genpd_lock_init(genpd);

	genpd->gov = gov;
@@ -1848,15 +1848,15 @@ static int genpd_remove(struct generic_pm_domain *genpd) 
		return -EBUSY;

	}



	if (!list_empty(&genpd->master_links) || genpd->device_count) {

	if (!list_empty(&genpd->parent_links) || genpd->device_count) {

		genpd_unlock(genpd);

		pr_err("%s: unable to remove %s\n", __func__, genpd->name);

		return -EBUSY;

	}



	list_for_each_entry_safe(link, l, &genpd->slave_links, slave_node) {

		list_del(&link->master_node);

		list_del(&link->slave_node);

	list_for_each_entry_safe(link, l, &genpd->child_links, child_node) {

		list_del(&link->parent_node);

		list_del(&link->child_node);

		kfree(link);

	}
@@ -2827,12 +2827,12 @@ static int genpd_summary_one(struct seq_file *s, 


	/*

	 * Modifications on the list require holding locks on both

	 * master and slave, so we are safe.

	 * parent and child, so we are safe.

	 * Also genpd->name is immutable.

	 */

	list_for_each_entry(link, &genpd->master_links, master_node) {

		seq_printf(s, "%s", link->slave->name);

		if (!list_is_last(&link->master_node, &genpd->master_links))

	list_for_each_entry(link, &genpd->parent_links, parent_node) {

		seq_printf(s, "%s", link->child->name);

		if (!list_is_last(&link->parent_node, &genpd->parent_links))

			seq_puts(s, ", ");

	}
@@ -2860,7 +2860,7 @@ static int summary_show(struct seq_file *s, void *data) 
	struct generic_pm_domain *genpd;

	int ret = 0;



	seq_puts(s, "domain                          status          slaves\n");

	seq_puts(s, "domain                          status          children\n");

	seq_puts(s, "    /device                                             runtime status\n");

	seq_puts(s, "----------------------------------------------------------------------\n");
@@ -2915,8 +2915,8 @@ static int sub_domains_show(struct seq_file *s, void *data) 
	if (ret)

		return -ERESTARTSYS;



	list_for_each_entry(link, &genpd->master_links, master_node)

		seq_printf(s, "%s\n", link->slave->name);

	list_for_each_entry(link, &genpd->parent_links, parent_node)

		seq_printf(s, "%s\n", link->child->name);



	genpd_unlock(genpd);

	return ret;

drivers/base/power/domain_governor.c

+6 −6
Original line number Diff line number Diff line
@@ -135,8 +135,8 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd, 
	 *

	 * All subdomains have been powered off already at this point.

	 */

	list_for_each_entry(link, &genpd->master_links, master_node) {

		struct generic_pm_domain *sd = link->slave;

	list_for_each_entry(link, &genpd->parent_links, parent_node) {

		struct generic_pm_domain *sd = link->child;

		s64 sd_max_off_ns = sd->max_off_time_ns;



		if (sd_max_off_ns < 0)
@@ -217,13 +217,13 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) 
	}



	/*

	 * We have to invalidate the cached results for the masters, so

	 * We have to invalidate the cached results for the parents, so

	 * use the observation that default_power_down_ok() is not

	 * going to be called for any master until this instance

	 * going to be called for any parent until this instance

	 * returns.

	 */

	list_for_each_entry(link, &genpd->slave_links, slave_node)

		link->master->max_off_time_changed = true;

	list_for_each_entry(link, &genpd->child_links, child_node)

		link->parent->max_off_time_changed = true;



	genpd->max_off_time_ns = -1;

	genpd->max_off_time_changed = false;

include/linux/pm_domain.h

+6 −6
Original line number Diff line number Diff line
@@ -95,8 +95,8 @@ struct generic_pm_domain { 
	struct device dev;

	struct dev_pm_domain domain;	/* PM domain operations */

	struct list_head gpd_list_node;	/* Node in the global PM domains list */

	struct list_head master_links;	/* Links with PM domain as a master */

	struct list_head slave_links;	/* Links with PM domain as a slave */

	struct list_head parent_links;	/* Links with PM domain as a parent */

	struct list_head child_links;/* Links with PM domain as a child */

	struct list_head dev_list;	/* List of devices */

	struct dev_power_governor *gov;

	struct work_struct power_off_work;
@@ -151,10 +151,10 @@ static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd) 
}



struct gpd_link {

	struct generic_pm_domain *master;

	struct list_head master_node;

	struct generic_pm_domain *slave;

	struct list_head slave_node;

	struct generic_pm_domain *parent;

	struct list_head parent_node;

	struct generic_pm_domain *child;

	struct list_head child_node;



	/* Sub-domain's per-master domain performance state */

	unsigned int performance_state;

scripts/gdb/linux/genpd.py

+6 −6
Original line number Diff line number Diff line
@@ -49,17 +49,17 @@ Output is similar to /sys/kernel/debug/pm_genpd/pm_genpd_summary''' 
        else:

            status_string = 'off-{}'.format(genpd['state_idx'])



        slave_names = []

        child_names = []

        for link in list_for_each_entry(

                genpd['master_links'],

                genpd['parent_links'],

                device_link_type.get_type().pointer(),

                'master_node'):

            slave_names.apend(link['slave']['name'])

                'parent_node'):

            child_names.append(link['child']['name'])



        gdb.write('%-30s  %-15s %s\n' % (

                genpd['name'].string(),

                status_string,

                ', '.join(slave_names)))

                ', '.join(child_names)))



        # Print devices in domain

        for pm_data in list_for_each_entry(genpd['dev_list'],
@@ -70,7 +70,7 @@ Output is similar to /sys/kernel/debug/pm_genpd/pm_genpd_summary''' 
            gdb.write('    %-50s  %s\n' % (kobj_path, rtpm_status_str(dev)))



    def invoke(self, arg, from_tty):

        gdb.write('domain                          status          slaves\n');

        gdb.write('domain                          status          children\n');

        gdb.write('    /device                                             runtime status\n');

        gdb.write('----------------------------------------------------------------------\n');

        for genpd in list_for_each_entry(

CRA Git | Maintained and supported by SUSTech CRA and CCSE