Commit 09f37134 authored by Tony Luck's avatar Tony Luck Committed by Borislav Petkov (AMD)
Browse files

x86,fs/resctrl: Consolidate monitor event descriptions 



There are currently only three monitor events, all associated with the
RDT_RESOURCE_L3 resource. Growing support for additional events will be easier
with some restructuring to have a single point in file system code where all
attributes of all events are defined.

Place all event descriptions into an array mon_event_all[]. Doing this has the
beneficial side effect of removing the need for rdt_resource::evt_list.

Add resctrl_event_id::QOS_FIRST_EVENT for a lower bound on range checks for
event ids and as the starting index to scan mon_event_all[].

Drop the code that builds evt_list and change the two places where the list is
scanned to scan mon_event_all[] instead using a new helper macro
for_each_mon_event().

Architecture code now informs file system code which events are available with
resctrl_enable_mon_event().

Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
Signed-off-by: default avatarBabu Moger <babu.moger@amd.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: default avatarFenghua Yu <fenghuay@nvidia.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
parent 0e58f6a7

arch/x86/kernel/cpu/resctrl/core.c

+9 −3
Original line number Diff line number Diff line
@@ -864,12 +864,18 @@ static __init bool get_rdt_mon_resources(void) 
{

	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;



	if (rdt_cpu_has(X86_FEATURE_CQM_OCCUP_LLC))

	if (rdt_cpu_has(X86_FEATURE_CQM_OCCUP_LLC)) {

		resctrl_enable_mon_event(QOS_L3_OCCUP_EVENT_ID);

		rdt_mon_features |= (1 << QOS_L3_OCCUP_EVENT_ID);

	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL))

	}

	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {

		resctrl_enable_mon_event(QOS_L3_MBM_TOTAL_EVENT_ID);

		rdt_mon_features |= (1 << QOS_L3_MBM_TOTAL_EVENT_ID);

	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))

	}

	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {

		resctrl_enable_mon_event(QOS_L3_MBM_LOCAL_EVENT_ID);

		rdt_mon_features |= (1 << QOS_L3_MBM_LOCAL_EVENT_ID);

	}



	if (!rdt_mon_features)

		return false;

fs/resctrl/internal.h

+10 −3
Original line number Diff line number Diff line
@@ -52,19 +52,26 @@ static inline struct rdt_fs_context *rdt_fc2context(struct fs_context *fc) 
}



/**

 * struct mon_evt - Entry in the event list of a resource

 * struct mon_evt - Properties of a monitor event

 * @evtid:		event id

 * @rid:		resource id for this event

 * @name:		name of the event

 * @configurable:	true if the event is configurable

 * @list:		entry in &rdt_resource->evt_list

 * @enabled:		true if the event is enabled

 */

struct mon_evt {

	enum resctrl_event_id	evtid;

	enum resctrl_res_level	rid;

	char			*name;

	bool			configurable;

	struct list_head	list;

	bool			enabled;

};



extern struct mon_evt mon_event_all[QOS_NUM_EVENTS];



#define for_each_mon_event(mevt) for (mevt = &mon_event_all[QOS_FIRST_EVENT];	\

				      mevt < &mon_event_all[QOS_NUM_EVENTS]; mevt++)



/**

 * struct mon_data - Monitoring details for each event file.

 * @list:            Member of the global @mon_data_kn_priv_list list.

fs/resctrl/monitor.c

+31 −32
Original line number Diff line number Diff line
@@ -842,38 +842,39 @@ static void dom_data_exit(struct rdt_resource *r) 
	mutex_unlock(&rdtgroup_mutex);

}



static struct mon_evt llc_occupancy_event = {

/*

 * All available events. Architecture code marks the ones that

 * are supported by a system using resctrl_enable_mon_event()

 * to set .enabled.

 */

struct mon_evt mon_event_all[QOS_NUM_EVENTS] = {

	[QOS_L3_OCCUP_EVENT_ID] = {

		.name	= "llc_occupancy",

		.evtid	= QOS_L3_OCCUP_EVENT_ID,

};



static struct mon_evt mbm_total_event = {

		.rid	= RDT_RESOURCE_L3,

	},

	[QOS_L3_MBM_TOTAL_EVENT_ID] = {

		.name	= "mbm_total_bytes",

		.evtid	= QOS_L3_MBM_TOTAL_EVENT_ID,

};



static struct mon_evt mbm_local_event = {

		.rid	= RDT_RESOURCE_L3,

	},

	[QOS_L3_MBM_LOCAL_EVENT_ID] = {

		.name	= "mbm_local_bytes",

		.evtid	= QOS_L3_MBM_LOCAL_EVENT_ID,

		.rid	= RDT_RESOURCE_L3,

	},

};



/*

 * Initialize the event list for the resource.

 *

 * Note that MBM events are also part of RDT_RESOURCE_L3 resource

 * because as per the SDM the total and local memory bandwidth

 * are enumerated as part of L3 monitoring.

 */

static void l3_mon_evt_init(struct rdt_resource *r)

void resctrl_enable_mon_event(enum resctrl_event_id eventid)

{

	INIT_LIST_HEAD(&r->evt_list);

	if (WARN_ON_ONCE(eventid < QOS_FIRST_EVENT || eventid >= QOS_NUM_EVENTS))

		return;

	if (mon_event_all[eventid].enabled) {

		pr_warn("Duplicate enable for event %d\n", eventid);

		return;

	}



	if (resctrl_arch_is_llc_occupancy_enabled())

		list_add_tail(&llc_occupancy_event.list, &r->evt_list);

	if (resctrl_arch_is_mbm_total_enabled())

		list_add_tail(&mbm_total_event.list, &r->evt_list);

	if (resctrl_arch_is_mbm_local_enabled())

		list_add_tail(&mbm_local_event.list, &r->evt_list);

	mon_event_all[eventid].enabled = true;

}



/**
@@ -900,15 +901,13 @@ int resctrl_mon_resource_init(void) 
	if (ret)

		return ret;



	l3_mon_evt_init(r);



	if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_TOTAL_EVENT_ID)) {

		mbm_total_event.configurable = true;

		mon_event_all[QOS_L3_MBM_TOTAL_EVENT_ID].configurable = true;

		resctrl_file_fflags_init("mbm_total_bytes_config",

					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);

	}

	if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_LOCAL_EVENT_ID)) {

		mbm_local_event.configurable = true;

		mon_event_all[QOS_L3_MBM_LOCAL_EVENT_ID].configurable = true;

		resctrl_file_fflags_init("mbm_local_bytes_config",

					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);

	}

fs/resctrl/rdtgroup.c

+6 −5
Original line number Diff line number Diff line
@@ -1152,7 +1152,9 @@ static int rdt_mon_features_show(struct kernfs_open_file *of, 
	struct rdt_resource *r = rdt_kn_parent_priv(of->kn);

	struct mon_evt *mevt;



	list_for_each_entry(mevt, &r->evt_list, list) {

	for_each_mon_event(mevt) {

		if (mevt->rid != r->rid || !mevt->enabled)

			continue;

		seq_printf(seq, "%s\n", mevt->name);

		if (mevt->configurable)

			seq_printf(seq, "%s_config\n", mevt->name);
@@ -3054,10 +3056,9 @@ static int mon_add_all_files(struct kernfs_node *kn, struct rdt_mon_domain *d, 
	struct mon_evt *mevt;

	int ret, domid;



	if (WARN_ON(list_empty(&r->evt_list)))

		return -EPERM;



	list_for_each_entry(mevt, &r->evt_list, list) {

	for_each_mon_event(mevt) {

		if (mevt->rid != r->rid || !mevt->enabled)

			continue;

		domid = do_sum ? d->ci_id : d->hdr.id;

		priv = mon_get_kn_priv(r->rid, domid, mevt, do_sum);

		if (WARN_ON_ONCE(!priv))

include/linux/resctrl.h

+2 −2
Original line number Diff line number Diff line
@@ -269,7 +269,6 @@ enum resctrl_schema_fmt { 
 * @mon_domains:	RCU list of all monitor domains for this resource

 * @name:		Name to use in "schemata" file.

 * @schema_fmt:		Which format string and parser is used for this schema.

 * @evt_list:		List of monitoring events

 * @mbm_cfg_mask:	Bandwidth sources that can be tracked when bandwidth

 *			monitoring events can be configured.

 * @cdp_capable:	Is the CDP feature available on this resource
@@ -287,7 +286,6 @@ struct rdt_resource { 
	struct list_head	mon_domains;

	char			*name;

	enum resctrl_schema_fmt	schema_fmt;

	struct list_head	evt_list;

	unsigned int		mbm_cfg_mask;

	bool			cdp_capable;

};
@@ -372,6 +370,8 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r); 
u32 resctrl_arch_system_num_rmid_idx(void);

int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);



void resctrl_enable_mon_event(enum resctrl_event_id eventid);



bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);



/**