Commit fb481ec0 authored by James Morse's avatar James Morse
Browse files

arm_mpam: resctrl: Call resctrl_init() on platforms that can support resctrl 



Now that MPAM links against resctrl, call resctrl_init() to register the
filesystem and setup resctrl's structures.

Tested-by: default avatarGavin Shan <gshan@redhat.com>
Tested-by: default avatarShaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: default avatarPeter Newman <peternewman@google.com>
Tested-by: default avatarZeng Heng <zengheng4@huawei.com>
Tested-by: default avatarPunit Agrawal <punit.agrawal@oss.qualcomm.com>
Tested-by: default avatarJesse Chick <jessechick@os.amperecomputing.com>
Reviewed-by: default avatarZeng Heng <zengheng4@huawei.com>
Reviewed-by: default avatarShaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: default avatarJonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: default avatarGavin Shan <gshan@redhat.com>
Co-developed-by: default avatarBen Horgan <ben.horgan@arm.com>
Signed-off-by: default avatarBen Horgan <ben.horgan@arm.com>
Signed-off-by: default avatarJames Morse <james.morse@arm.com>
parent 4aab135b

drivers/resctrl/mpam_devices.c

+28 −4
Original line number Diff line number Diff line
@@ -73,6 +73,14 @@ static DECLARE_WORK(mpam_broken_work, &mpam_disable); 
/* When mpam is disabled, the printed reason to aid debugging */

static char *mpam_disable_reason;



/*

 * Whether resctrl has been setup. Used by cpuhp in preference to

 * mpam_is_enabled(). The disable call after an error interrupt makes

 * mpam_is_enabled() false before the cpuhp callbacks are made.

 * Reads/writes should hold mpam_cpuhp_state_lock, (or be cpuhp callbacks).

 */

static bool mpam_resctrl_enabled;



/*

 * An MSC is a physical container for controls and monitors, each identified by

 * their RIS index. These share a base-address, interrupts and some MMIO
@@ -1619,7 +1627,7 @@ static int mpam_cpu_online(unsigned int cpu) 
			mpam_reprogram_msc(msc);

	}



	if (mpam_is_enabled())

	if (mpam_resctrl_enabled)

		return mpam_resctrl_online_cpu(cpu);



	return 0;
@@ -1665,7 +1673,7 @@ static int mpam_cpu_offline(unsigned int cpu) 
{

	struct mpam_msc *msc;



	if (mpam_is_enabled())

	if (mpam_resctrl_enabled)

		mpam_resctrl_offline_cpu(cpu);



	guard(srcu)(&mpam_srcu);
@@ -2526,6 +2534,7 @@ static void mpam_enable_once(void) 
	}



	static_branch_enable(&mpam_enabled);

	mpam_resctrl_enabled = true;

	mpam_register_cpuhp_callbacks(mpam_cpu_online, mpam_cpu_offline,

				      "mpam:online");
@@ -2585,24 +2594,39 @@ static void mpam_reset_class(struct mpam_class *class) 
void mpam_disable(struct work_struct *ignored)

{

	int idx;

	bool do_resctrl_exit;

	struct mpam_class *class;

	struct mpam_msc *msc, *tmp;



	if (mpam_is_enabled())

		static_branch_disable(&mpam_enabled);



	mutex_lock(&mpam_cpuhp_state_lock);

	if (mpam_cpuhp_state) {

		cpuhp_remove_state(mpam_cpuhp_state);

		mpam_cpuhp_state = 0;

	}



	/*

	 * Removing the cpuhp state called mpam_cpu_offline() and told resctrl

	 * all the CPUs are offline.

	 */

	do_resctrl_exit = mpam_resctrl_enabled;

	mpam_resctrl_enabled = false;

	mutex_unlock(&mpam_cpuhp_state_lock);



	static_branch_disable(&mpam_enabled);

	if (do_resctrl_exit)

		mpam_resctrl_exit();



	mpam_unregister_irqs();



	idx = srcu_read_lock(&mpam_srcu);

	list_for_each_entry_srcu(class, &mpam_classes, classes_list,

				 srcu_read_lock_held(&mpam_srcu))

				 srcu_read_lock_held(&mpam_srcu)) {

		mpam_reset_class(class);

		if (do_resctrl_exit)

			mpam_resctrl_teardown_class(class);

	}

	srcu_read_unlock(&mpam_srcu, idx);



	mutex_lock(&mpam_list_lock);

drivers/resctrl/mpam_internal.h

+4 −0
Original line number Diff line number Diff line
@@ -431,12 +431,16 @@ int mpam_get_cpumask_from_cache_id(unsigned long cache_id, u32 cache_level, 


#ifdef CONFIG_RESCTRL_FS

int mpam_resctrl_setup(void);

void mpam_resctrl_exit(void);

int mpam_resctrl_online_cpu(unsigned int cpu);

void mpam_resctrl_offline_cpu(unsigned int cpu);

void mpam_resctrl_teardown_class(struct mpam_class *class);

#else

static inline int mpam_resctrl_setup(void) { return 0; }

static inline void mpam_resctrl_exit(void) { }

static inline int mpam_resctrl_online_cpu(unsigned int cpu) { return 0; }

static inline void mpam_resctrl_offline_cpu(unsigned int cpu) { }

static inline void mpam_resctrl_teardown_class(struct mpam_class *class) { }

#endif /* CONFIG_RESCTRL_FS */



/*

drivers/resctrl/mpam_resctrl.c

+62 −1
Original line number Diff line number Diff line
@@ -69,6 +69,12 @@ static bool cdp_enabled; 
static bool cacheinfo_ready;

static DECLARE_WAIT_QUEUE_HEAD(wait_cacheinfo_ready);



/*

 * If resctrl_init() succeeded, resctrl_exit() can be used to remove support

 * for the filesystem in the event of an error.

 */

static bool resctrl_enabled;



bool resctrl_arch_alloc_capable(void)

{

	struct mpam_resctrl_res *res;
@@ -360,6 +366,9 @@ static int resctrl_arch_mon_ctx_alloc_no_wait(enum resctrl_event_id evtid) 
{

	struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[evtid];



	if (!mpam_is_enabled())

		return -EINVAL;



	if (!mon->class)

		return -EINVAL;
@@ -402,6 +411,9 @@ static void resctrl_arch_mon_ctx_free_no_wait(enum resctrl_event_id evtid, 
{

	struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[evtid];



	if (!mpam_is_enabled())

		return;



	if (!mon->class)

		return;
@@ -488,6 +500,9 @@ int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain_hdr *hdr, 


	resctrl_arch_rmid_read_context_check();



	if (!mpam_is_enabled())

		return -EINVAL;



	if (eventid >= QOS_NUM_EVENTS || !mon->class)

		return -EINVAL;
@@ -1162,6 +1177,9 @@ int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_ctrl_domain *d, 
	lockdep_assert_cpus_held();

	lockdep_assert_irqs_enabled();



	if (!mpam_is_enabled())

		return -EINVAL;



	/*

	 * No need to check the CPU as mpam_apply_config() doesn't care, and

	 * resctrl_arch_update_domains() relies on this.
@@ -1227,6 +1245,9 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) 
	lockdep_assert_cpus_held();

	lockdep_assert_irqs_enabled();



	if (!mpam_is_enabled())

		return -EINVAL;



	list_for_each_entry_rcu(d, &r->ctrl_domains, hdr.list) {

		for (enum resctrl_conf_type t = 0; t < CDP_NUM_TYPES; t++) {

			struct resctrl_staged_config *cfg = &d->staged_config[t];
@@ -1619,7 +1640,11 @@ int mpam_resctrl_setup(void) 
		return -EOPNOTSUPP;

	}



	/* TODO: call resctrl_init() */

	err = resctrl_init();

	if (err)

		return err;



	WRITE_ONCE(resctrl_enabled, true);



	return 0;
@@ -1629,6 +1654,42 @@ int mpam_resctrl_setup(void) 
	return err;

}



void mpam_resctrl_exit(void)

{

	if (!READ_ONCE(resctrl_enabled))

		return;



	WRITE_ONCE(resctrl_enabled, false);

	resctrl_exit();

}



/*

 * The driver is detaching an MSC from this class, if resctrl was using it,

 * pull on resctrl_exit().

 */

void mpam_resctrl_teardown_class(struct mpam_class *class)

{

	struct mpam_resctrl_res *res;

	enum resctrl_res_level rid;

	struct mpam_resctrl_mon *mon;

	enum resctrl_event_id eventid;



	might_sleep();



	for_each_mpam_resctrl_control(res, rid) {

		if (res->class == class) {

			res->class = NULL;

			break;

		}

	}

	for_each_mpam_resctrl_mon(mon, eventid) {

		if (mon->class == class) {

			mon->class = NULL;

			break;

		}

	}

}



static int __init __cacheinfo_ready(void)

{

	cacheinfo_ready = true;