[PATCH V2 0/6] perf: Driver specific configuration for PMU

@@ -68,8 +68,10 @@ static size_t buf_size(struct page *page)
 }
 
 static void *
-bts_buffer_setup_aux(int cpu, void **pages, int nr_pages, bool overwrite)
+bts_buffer_setup_aux(struct perf_event *event, void **pages,
+		     int nr_pages, bool overwrite)
 {
+	int cpu = event->cpu;
 	struct bts_buffer *buf;
 	struct page *page;
 	int node = (cpu == -1) ? cpu : cpu_to_node(cpu);

@@ -1003,10 +1003,11 @@ static int pt_buffer_init_topa(struct pt_buffer *buf, unsigned long nr_pages,
  * Return:	Our private PT buffer structure.
  */
 static void *
-pt_buffer_setup_aux(int cpu, void **pages, int nr_pages, bool snapshot)
+pt_buffer_setup_aux(struct perf_event *event, void **pages,
+		    int nr_pages, bool snapshot)
 {
 	struct pt_buffer *buf;
-	int node, ret;
+	int node, ret, cpu = event->cpu;
 
 	if (!nr_pages)
 		return NULL;

@@ -155,7 +155,7 @@ static void etm_free_aux(void *data)
 	schedule_work(&event_data->work);
 }
 
-static void *etm_setup_aux(int event_cpu, void **pages,
+static void *etm_setup_aux(struct perf_event *event, void **pages,
 			   int nr_pages, bool overwrite)
 {
 	int cpu;

@@ -163,7 +163,7 @@ static void *etm_setup_aux(int event_cpu, void **pages,
 	struct coresight_device *sink;
 	struct etm_event_data *event_data = NULL;
 
-	event_data = alloc_event_data(event_cpu);
+	event_data = alloc_event_data(event->cpu);
 	if (!event_data)
 		return NULL;
 

@@ -407,7 +407,7 @@ struct pmu {
 	/*
 	 * Set up pmu-private data structures for an AUX area
 	 */
-	void *(*setup_aux)		(int cpu, void **pages,
+	void *(*setup_aux)		(struct perf_event *event, void **pages,
 					 int nr_pages, bool overwrite);
 					/* optional */
 

@@ -616,7 +616,7 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
 			goto out;
 	}
 
-	rb->aux_priv = event->pmu->setup_aux(event->cpu, rb->aux_pages, nr_pages,
+	rb->aux_priv = event->pmu->setup_aux(event, rb->aux_pages, nr_pages,
 					     overwrite);
 	if (!rb->aux_priv)
 		goto out;

@@ -383,6 +383,7 @@ static int record__open(struct record *rec)
 	struct perf_evlist *evlist = rec->evlist;
 	struct perf_session *session = rec->session;
 	struct record_opts *opts = &rec->opts;
+	struct perf_evsel_config_term *err_term;
 	int rc = 0;
 
 	perf_evlist__config(evlist, opts, &callchain_param);

@@ -412,6 +413,14 @@ try_again:
 		goto out;
 	}
 
+	if (perf_evlist__apply_drv_configs(evlist, &pos, &err_term)) {
+		error("failed to set config \"%s\" on event %s with %d (%s)\n",
+			err_term->val.drv_cfg, perf_evsel__name(pos), errno,
+			strerror_r(errno, msg, sizeof(msg)));
+		rc = -1;
+		goto out;
+	}
+
 	rc = record__mmap(rec);
 	if (rc)
 		goto out;

@@ -1433,6 +1433,30 @@ int perf_evlist__apply_filters(struct perf_evlist *evlist, struct perf_evsel **e
 	return err;
 }
 
+int perf_evlist__apply_drv_configs(struct perf_evlist *evlist,
+				   struct perf_evsel **err_evsel,
+				   struct perf_evsel_config_term **err_term)
+{
+	struct perf_evsel *evsel;
+	int err = 0;
+	const int ncpus = cpu_map__nr(evlist->cpus),
+		  nthreads = thread_map__nr(evlist->threads);
+
+	evlist__for_each_entry(evlist, evsel) {
+		if (list_empty(&evsel->drv_config_terms))
+			continue;
+
+		err = perf_evsel__apply_drv_configs(evsel, ncpus,
+						    nthreads, err_term);
+		if (err) {
+			*err_evsel = evsel;
+			break;
+		}
+	}
+
+	return err;
+}
+
 int perf_evlist__set_filter(struct perf_evlist *evlist, const char *filter)
 {
 	struct perf_evsel *evsel;

@@ -232,6 +232,9 @@ void perf_evlist__set_maps(struct perf_evlist *evlist, struct cpu_map *cpus,
 			   struct thread_map *threads);
 int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target);
 int perf_evlist__apply_filters(struct perf_evlist *evlist, struct perf_evsel **err_evsel);
+int perf_evlist__apply_drv_configs(struct perf_evlist *evlist,
+				   struct perf_evsel **err_evsel,
+				   struct perf_evsel_config_term **term);
 
 void __perf_evlist__set_leader(struct list_head *list);
 void perf_evlist__set_leader(struct perf_evlist *evlist);

@@ -1035,6 +1035,27 @@ int perf_evsel__append_filter(struct perf_evsel *evsel,
 	return -1;
 }
 
+int perf_evsel__apply_drv_configs(struct perf_evsel *evsel,
+				  int ncpus, int nthreads,
+				  struct perf_evsel_config_term **err_term)
+{
+	int err = 0;
+	struct perf_evsel_config_term *term;
+
+	list_for_each_entry(term, &evsel->drv_config_terms, list) {
+		err = perf_evsel__run_ioctl(evsel, ncpus, nthreads,
+					    PERF_EVENT_IOC_SET_DRV_CONFIGS,
+					    (void *)term->val.drv_cfg);
+
+		if (err) {
+			*err_term = term;
+			break;
+		}
+	}
+
+	return err;
+}
+
 int perf_evsel__enable(struct perf_evsel *evsel)
 {
 	int nthreads = thread_map__nr(evsel->threads);

@@ -1100,6 +1121,16 @@ static void perf_evsel__free_config_terms(struct perf_evsel *evsel)
 	}
 }
 
+static void perf_evsel__free_drv_config_terms(struct perf_evsel *evsel)
+{
+	struct perf_evsel_config_term *term, *h;
+
+	list_for_each_entry_safe(term, h, &evsel->drv_config_terms, list) {
+		list_del(&term->list);
+		free(term);
+	}
+}
+
 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
 {
 	int cpu, thread;

@@ -1121,6 +1152,7 @@ void perf_evsel__exit(struct perf_evsel *evsel)
 	perf_evsel__free_fd(evsel);
 	perf_evsel__free_id(evsel);
 	perf_evsel__free_config_terms(evsel);
+	perf_evsel__free_drv_config_terms(evsel);
 	close_cgroup(evsel->cgrp);
 	cpu_map__put(evsel->cpus);
 	cpu_map__put(evsel->own_cpus);

@@ -239,6 +239,9 @@ int perf_evsel__append_filter(struct perf_evsel *evsel,
 			      const char *op, const char *filter);
 int perf_evsel__apply_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
 			     const char *filter);
+int perf_evsel__apply_drv_configs(struct perf_evsel *evsel,
+				  int ncpus, int nthreads,
+				  struct perf_evsel_config_term **err_term);
 int perf_evsel__enable(struct perf_evsel *evsel);
 int perf_evsel__disable(struct perf_evsel *evsel);
 

@@ -22,6 +22,7 @@
 #include <linux/list.h>
 #include <linux/mm.h>
 #include <linux/init.h>
+#include <linux/parser.h>
 #include <linux/perf_event.h>
 #include <linux/slab.h>
 #include <linux/types.h>

@@ -71,11 +72,20 @@ static const struct attribute_group *etm_pmu_attr_groups[] = {
 
 static void etm_event_read(struct perf_event *event) {}
 
+static void etm_event_destroy(struct perf_event *event)
+{
+	kfree(event->hw.drv_configs);
+	event->hw.drv_configs = NULL;
+}
+
 static int etm_event_init(struct perf_event *event)
 {
 	if (event->attr.type != etm_pmu.type)
 		return -ENOENT;
 
+	event->destroy = etm_event_destroy;
+	event->hw.drv_configs = NULL;
+
 	return 0;
 }
 

@@ -159,6 +169,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
 			   int nr_pages, bool overwrite)
 {
 	int cpu;
+	char *cmdl_sink;
 	cpumask_t *mask;
 	struct coresight_device *sink;
 	struct etm_event_data *event_data = NULL;

@@ -171,6 +182,12 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
 
 	mask = &event_data->mask;
 
+	/*
+	 * If a sink was specified from the perf cmdline it will be part of
+	 * the event's drv_configs.
+	 */
+	cmdl_sink = (char *)event->hw.drv_configs;
+
 	/* Setup the path for each CPU in a trace session */
 	for_each_cpu(cpu, mask) {
 		struct coresight_device *csdev;

@@ -184,7 +201,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
 		 * list of devices from source to sink that can be
 		 * referenced later when the path is actually needed.
 		 */
-		event_data->path[cpu] = coresight_build_path(csdev, NULL);
+		event_data->path[cpu] = coresight_build_path(csdev, cmdl_sink);
 		if (!event_data->path[cpu])
 			goto err;
 	}

@@ -342,6 +359,87 @@ static void etm_event_del(struct perf_event *event, int mode)
 	etm_event_stop(event, PERF_EF_UPDATE);
 }
 
+enum {
+	ETM_TOKEN_SINK_CPU,
+	ETM_TOKEN_SINK,
+	ETM_TOKEN_ERR,
+};
+
+static const match_table_t drv_cfg_tokens = {
+	{ETM_TOKEN_SINK_CPU, "sink=cpu%d:%s"},
+	{ETM_TOKEN_SINK, "sink=%s"},
+	{ETM_TOKEN_ERR, NULL},
+};
+
+static int etm_set_drv_configs(struct perf_event *event, void __user *arg)
+{
+	char *config, *sink = NULL;
+	int cpu = -1, token, ret = 0;
+	substring_t args[MAX_OPT_ARGS];
+
+	/* Only one sink per event */
+	if (event->hw.drv_configs != NULL) {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	/* Make user supplied input usable */
+	config = strndup_user(arg, PAGE_SIZE);
+	if (IS_ERR(config)) {
+		ret = PTR_ERR(config);
+		goto err;
+	}
+
+	/* See above declared @drv_cfg_tokens for the usable formats */
+	token = match_token(config, drv_cfg_tokens, args);
+	switch (token) {
+	case ETM_TOKEN_SINK:
+		/* Just a sink has been specified */
+		sink = match_strdup(&args[0]);
+		if (IS_ERR(sink)) {
+			ret = PTR_ERR(sink);
+			goto err;
+		}
+		break;
+	case ETM_TOKEN_SINK_CPU:
+		/* We have a sink and a CPU */
+
+		/* First get the cpu */
+		if (match_int(&args[0], &cpu)) {
+			ret = -EINVAL;
+			goto err;
+		}
+
+		/* Then the sink */
+		sink = match_strdup(&args[1]);
+		if (IS_ERR(sink)) {
+			ret = PTR_ERR(sink);
+			goto err;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+		goto err;
+	}
+
+	/*
+	 * If the CPUs don't match the sink is destined to another path.  This
+	 * isn't as an error hence not setting @ret.
+	 */
+	if (event->cpu != cpu)
+		goto err;
+
+	/* We have a valid configuration */
+	event->hw.drv_configs = sink;
+
+out:
+	return ret;
+
+err:
+	kfree(sink);
+	goto out;
+}
+
 int etm_perf_symlink(struct coresight_device *csdev, bool link)
 {
 	char entry[sizeof("cpu9999999")];

@@ -383,6 +481,7 @@ static int __init etm_perf_init(void)
 	etm_pmu.stop		= etm_event_stop;
 	etm_pmu.add		= etm_event_add;
 	etm_pmu.del		= etm_event_del;
+	etm_pmu.set_drv_configs	= etm_set_drv_configs;
 
 	ret = perf_pmu_register(&etm_pmu, CORESIGHT_ETM_PMU_NAME, -1);
 	if (ret == 0)

@@ -184,7 +184,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
 		 * list of devices from source to sink that can be
 		 * referenced later when the path is actually needed.
 		 */
-		event_data->path[cpu] = coresight_build_path(csdev);
+		event_data->path[cpu] = coresight_build_path(csdev, NULL);
 		if (!event_data->path[cpu])
 			goto err;
 	}

@@ -94,7 +94,8 @@ static inline void CS_UNLOCK(void __iomem *addr)
 void coresight_disable_path(struct list_head *path);
 int coresight_enable_path(struct list_head *path, u32 mode);
 struct coresight_device *coresight_get_sink(struct list_head *path);
-struct list_head *coresight_build_path(struct coresight_device *csdev);
+struct list_head *coresight_build_path(struct coresight_device *csdev,
+				       const char *sink);
 void coresight_release_path(struct list_head *path);
 
 #ifdef CONFIG_CORESIGHT_SOURCE_ETM3X

@@ -372,30 +372,41 @@ struct coresight_device *coresight_get_sink(struct list_head *path)
  * _coresight_build_path - recursively build a path from a @csdev to a sink.
  * @csdev:	The device to start from.
  * @path:	The list to add devices to.
+ * @sink:	The name of the sink this path should connect with.
  *
- * The tree of Coresight device is traversed until an activated sink is
- * found.  From there the sink is added to the list along with all the
- * devices that led to that point - the end result is a list from source
- * to sink. In that list the source is the first device and the sink the
- * last one.
+ * The tree of Coresight device is traversed until an activated sink or
+ * the one specified by @sink is found.
+ * From there the sink is added to the list along with all the devices that
+ * led to that point - the end result is a list from source to sink. In that
+ * list the source is the first device and the sink the last one.
  */
 static int _coresight_build_path(struct coresight_device *csdev,
-				 struct list_head *path)
+				 struct list_head *path, const char *sink)
 {
 	int i;
 	bool found = false;
 	struct coresight_node *node;
 
-	/* An activated sink has been found.  Enqueue the element */
-	if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
-	     csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) && csdev->activated)
-		goto out;
+	/*
+	 * First see if we are dealing with a sink.  If we have one check if
+	 * it was selected via sysFS or the perf cmd line.
+	 */
+	if (csdev->type == CORESIGHT_DEV_TYPE_SINK ||
+	    csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) {
+		/* Activated via perf cmd line */
+		if (sink && !strcmp(dev_name(&csdev->dev), sink))
+			goto out;
+		/* Activated via sysFS */
+		if (csdev->activated)
+			goto out;
+	}
 
 	/* Not a sink - recursively explore each port found on this element */
 	for (i = 0; i < csdev->nr_outport; i++) {
 		struct coresight_device *child_dev = csdev->conns[i].child_dev;
 
-		if (child_dev && _coresight_build_path(child_dev, path) == 0) {
+		if (child_dev &&
+		    _coresight_build_path(child_dev, path, sink) == 0) {
 			found = true;
 			break;
 		}

@@ -422,7 +433,8 @@ out:
 	return 0;
 }
 
-struct list_head *coresight_build_path(struct coresight_device *csdev)
+struct list_head *coresight_build_path(struct coresight_device *csdev,
+				       const char *sink)
 {
 	struct list_head *path;
 	int rc;

@@ -433,7 +445,7 @@ struct list_head *coresight_build_path(struct coresight_device *csdev)
 
 	INIT_LIST_HEAD(path);
 
-	rc = _coresight_build_path(csdev, path);
+	rc = _coresight_build_path(csdev, path, sink);
 	if (rc) {
 		kfree(path);
 		return ERR_PTR(rc);

@@ -508,7 +520,7 @@ int coresight_enable(struct coresight_device *csdev)
 	if (csdev->enable)
 		goto out;
 
-	path = coresight_build_path(csdev);
+	path = coresight_build_path(csdev, NULL);
 	if (IS_ERR(path)) {
 		pr_err("building path(s) failed\n");
 		ret = PTR_ERR(path);

@@ -231,6 +231,7 @@ void perf_evsel__init(struct perf_evsel *evsel,
 	evsel->bpf_fd	   = -1;
 	INIT_LIST_HEAD(&evsel->node);
 	INIT_LIST_HEAD(&evsel->config_terms);
+	INIT_LIST_HEAD(&evsel->drv_config_terms);
 	perf_evsel__object.init(evsel);
 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
 	perf_evsel__calc_id_pos(evsel);

@@ -46,6 +46,7 @@ enum {
 	PERF_EVSEL__CONFIG_TERM_INHERIT,
 	PERF_EVSEL__CONFIG_TERM_MAX_STACK,
 	PERF_EVSEL__CONFIG_TERM_OVERWRITE,
+	PERF_EVSEL__CONFIG_TERM_DRV_CFG,
 	PERF_EVSEL__CONFIG_TERM_MAX,
 };
 

@@ -57,6 +58,7 @@ struct perf_evsel_config_term {
 		u64	freq;
 		bool	time;
 		char	*callgraph;
+		char	*drv_cfg;
 		u64	stack_user;
 		int	max_stack;
 		bool	inherit;

@@ -79,6 +81,7 @@ struct perf_evsel_config_term {
  *          PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if sample_id_all
  *          is used there is an id sample appended to non-sample events
  * @priv:   And what is in its containing unnamed union are tool specific
+ * @drv_config_terms: List of configurables sent directly to the PMU driver
  */
 struct perf_evsel {
 	struct list_head	node;

@@ -125,6 +128,7 @@ struct perf_evsel {
 	char			*group_name;
 	bool			cmdline_group_boundary;
 	struct list_head	config_terms;
+	struct list_head	drv_config_terms;
 	int			bpf_fd;
 };
 

@@ -303,7 +303,8 @@ static struct perf_evsel *
 __add_event(struct list_head *list, int *idx,
 	    struct perf_event_attr *attr,
 	    char *name, struct cpu_map *cpus,
-	    struct list_head *config_terms)
+	    struct list_head *config_terms,
+	    struct list_head *drv_config_terms)
 {
 	struct perf_evsel *evsel;
 

@@ -322,6 +323,10 @@ __add_event(struct list_head *list, int *idx,
 	if (config_terms)
 		list_splice(config_terms, &evsel->config_terms);
 
+	if (drv_config_terms)
+		list_splice(drv_config_terms, &evsel->drv_config_terms);
+
+
 	list_add_tail(&evsel->node, list);
 	return evsel;
 }

@@ -330,7 +335,8 @@ static int add_event(struct list_head *list, int *idx,
 		     struct perf_event_attr *attr, char *name,
 		     struct list_head *config_terms)
 {
-	return __add_event(list, idx, attr, name, NULL, config_terms) ? 0 : -ENOMEM;
+	return __add_event(list, idx, attr, name,
+			   NULL, config_terms, NULL) ? 0 : -ENOMEM;
 }
 
 static int parse_aliases(char *str, const char *names[][PERF_EVSEL__MAX_ALIASES], int size)

@@ -904,6 +910,7 @@ static const char *config_term_names[__PARSE_EVENTS__TERM_TYPE_NR] = {
 	[PARSE_EVENTS__TERM_TYPE_MAX_STACK]		= "max-stack",
 	[PARSE_EVENTS__TERM_TYPE_OVERWRITE]		= "overwrite",
 	[PARSE_EVENTS__TERM_TYPE_NOOVERWRITE]		= "no-overwrite",
+	[PARSE_EVENTS__TERM_TYPE_DRV_CFG]		= "driver-config",
 };
 
 static bool config_term_shrinked;

@@ -1034,7 +1041,8 @@ static int config_term_pmu(struct perf_event_attr *attr,
 			   struct parse_events_term *term,
 			   struct parse_events_error *err)
 {
-	if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER)
+	if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER ||
+	    term->type_term == PARSE_EVENTS__TERM_TYPE_DRV_CFG)
 		/*
 		 * Always succeed for sysfs terms, as we dont know
 		 * at this point what type they need to have.

@@ -1083,10 +1091,7 @@ static int config_attr(struct perf_event_attr *attr,
 	return 0;
 }
 
-static int get_config_terms(struct list_head *head_config,
-			    struct list_head *head_terms __maybe_unused)
-{
-#define ADD_CONFIG_TERM(__type, __name, __val)			\
+#define ADD_CONFIG_TERM(__type, __name, __val, __head_terms)	\
 do {								\
 	struct perf_evsel_config_term *__t;			\
 								\

@@ -1097,42 +1102,53 @@ do {								\
 	INIT_LIST_HEAD(&__t->list);				\
 	__t->type       = PERF_EVSEL__CONFIG_TERM_ ## __type;	\
 	__t->val.__name = __val;				\
-	list_add_tail(&__t->list, head_terms);			\
+	list_add_tail(&__t->list, __head_terms);		\
 } while (0)
 
+static int get_config_terms(struct list_head *head_config,
+			    struct list_head *head_terms)
+{
 	struct parse_events_term *term;
 
 	list_for_each_entry(term, head_config, list) {
 		switch (term->type_term) {
 		case PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD:
-			ADD_CONFIG_TERM(PERIOD, period, term->val.num);
+			ADD_CONFIG_TERM(PERIOD, period,
+					term->val.num, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_SAMPLE_FREQ:
-			ADD_CONFIG_TERM(FREQ, freq, term->val.num);
+			ADD_CONFIG_TERM(FREQ, freq, term->val.num, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_TIME:
-			ADD_CONFIG_TERM(TIME, time, term->val.num);
+			ADD_CONFIG_TERM(TIME, time, term->val.num, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_CALLGRAPH:
-			ADD_CONFIG_TERM(CALLGRAPH, callgraph, term->val.str);
+			ADD_CONFIG_TERM(CALLGRAPH, callgraph,
+					term->val.str, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_STACKSIZE:
-			ADD_CONFIG_TERM(STACK_USER, stack_user, term->val.num);
+			ADD_CONFIG_TERM(STACK_USER, stack_user,
+					term->val.num, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_INHERIT:
-			ADD_CONFIG_TERM(INHERIT, inherit, term->val.num ? 1 : 0);
+			ADD_CONFIG_TERM(INHERIT, inherit,
+					term->val.num ? 1 : 0, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_NOINHERIT:
-			ADD_CONFIG_TERM(INHERIT, inherit, term->val.num ? 0 : 1);
+			ADD_CONFIG_TERM(INHERIT, inherit,
+					term->val.num ? 0 : 1, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_MAX_STACK:
-			ADD_CONFIG_TERM(MAX_STACK, max_stack, term->val.num);
+			ADD_CONFIG_TERM(MAX_STACK, max_stack,
+					term->val.num, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_OVERWRITE:
-			ADD_CONFIG_TERM(OVERWRITE, overwrite, term->val.num ? 1 : 0);
+			ADD_CONFIG_TERM(OVERWRITE, overwrite,
+					term->val.num ? 1 : 0, head_terms);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_NOOVERWRITE:
-			ADD_CONFIG_TERM(OVERWRITE, overwrite, term->val.num ? 0 : 1);
+			ADD_CONFIG_TERM(OVERWRITE, overwrite,
+					term->val.num ? 0 : 1, head_terms);
 			break;
 		default:
 			break;

@@ -1142,6 +1158,21 @@ do {								\
 	return 0;
 }
 
+static int get_drv_config_terms(struct list_head *head_config,
+				struct list_head *head_terms)
+{
+	struct parse_events_term *term;
+
+	list_for_each_entry(term, head_config, list) {
+		if (term->type_term != PARSE_EVENTS__TERM_TYPE_DRV_CFG)
+			continue;
+
+		ADD_CONFIG_TERM(DRV_CFG, drv_cfg, term->val.str, head_terms);
+	}
+
+	return 0;
+}
+
 int parse_events_add_tracepoint(struct list_head *list, int *idx,
 				const char *sys, const char *event,
 				struct parse_events_error *err,

@@ -1197,6 +1228,7 @@ int parse_events_add_pmu(struct parse_events_evlist *data,
 	struct perf_pmu *pmu;
 	struct perf_evsel *evsel;
 	LIST_HEAD(config_terms);
+	LIST_HEAD(drv_config_terms);
 
 	pmu = perf_pmu__find(name);
 	if (!pmu)

@@ -1211,7 +1243,8 @@ int parse_events_add_pmu(struct parse_events_evlist *data,
 
 	if (!head_config) {
 		attr.type = pmu->type;
-		evsel = __add_event(list, &data->idx, &attr, NULL, pmu->cpus, NULL);
+		evsel = __add_event(list, &data->idx, &attr,
+				    NULL, pmu->cpus, NULL, NULL);
 		return evsel ? 0 : -ENOMEM;
 	}
 

@@ -1228,12 +1261,15 @@ int parse_events_add_pmu(struct parse_events_evlist *data,
 	if (get_config_terms(head_config, &config_terms))
 		return -ENOMEM;
 
+	if (get_drv_config_terms(head_config, &drv_config_terms))
+		return -ENOMEM;
+
 	if (perf_pmu__config(pmu, &attr, head_config, data->error))
 		return -EINVAL;
 
 	evsel = __add_event(list, &data->idx, &attr,
 			    get_config_name(head_config), pmu->cpus,
-			    &config_terms);
+			    &config_terms, &drv_config_terms);
 	if (evsel) {
 		evsel->unit = info.unit;
 		evsel->scale = info.scale;

@@ -71,6 +71,7 @@ enum {
 	PARSE_EVENTS__TERM_TYPE_MAX_STACK,
 	PARSE_EVENTS__TERM_TYPE_NOOVERWRITE,
 	PARSE_EVENTS__TERM_TYPE_OVERWRITE,
+	PARSE_EVENTS__TERM_TYPE_DRV_CFG,
 	__PARSE_EVENTS__TERM_TYPE_NR,
 };
 

@@ -53,6 +53,16 @@ static int str(yyscan_t scanner, int token)
 	return token;
 }
 
+static int drv_str(yyscan_t scanner, int token)
+{
+	YYSTYPE *yylval = parse_events_get_lval(scanner);
+	char *text = parse_events_get_text(scanner);
+
+	/* Strip off the '@' */
+	yylval->str = strdup(text + 1);
+	return token;
+}
+
 #define REWIND(__alloc)				\
 do {								\
 	YYSTYPE *__yylval = parse_events_get_lval(yyscanner);	\

@@ -124,6 +134,7 @@ num_hex		0x[a-fA-F0-9]+
 num_raw_hex	[a-fA-F0-9]+
 name		[a-zA-Z_*?][a-zA-Z0-9_*?.]*
 name_minus	[a-zA-Z_*?][a-zA-Z0-9\-_*?.:]*
+drv_cfg_term	[a-zA-Z0-9_\.]+(=[a-zA-Z0-9_*?\.:]+)?
 /* If you add a modifier you need to update check_modifier() */
 modifier_event	[ukhpPGHSDI]+
 modifier_bp	[rwx]{1,3}

@@ -209,6 +220,7 @@ no-overwrite		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NOOVERWRITE); }
 {name_minus}		{ return str(yyscanner, PE_NAME); }
 \[all\]			{ return PE_ARRAY_ALL; }
 "["			{ BEGIN(array); return '['; }
+@{drv_cfg_term}		{ return drv_str(yyscanner, PE_DRV_CFG_TERM); }
 }
 
 <mem>{

@@ -49,6 +49,7 @@ static void inc_group_count(struct list_head *list,
 %token PE_ERROR
 %token PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT
 %token PE_ARRAY_ALL PE_ARRAY_RANGE
+%token PE_DRV_CFG_TERM
 %type <num> PE_VALUE
 %type <num> PE_VALUE_SYM_HW
 %type <num> PE_VALUE_SYM_SW

@@ -63,6 +64,7 @@ static void inc_group_count(struct list_head *list,
 %type <str> PE_MODIFIER_BP
 %type <str> PE_EVENT_NAME
 %type <str> PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT
+%type <str> PE_DRV_CFG_TERM
 %type <num> value_sym
 %type <head> event_config
 %type <head> opt_event_config

@@ -599,6 +601,15 @@ PE_NAME array '=' PE_VALUE
 	term->array = $2;
 	$$ = term;
 }
+|
+PE_DRV_CFG_TERM
+{
+	struct parse_events_term *term;
+
+	ABORT_ON(parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_DRV_CFG,
+					$1, $1, &@1, NULL));
+	$$ = term;
+}
 
 array:
 '[' array_terms ']'

@@ -168,6 +168,9 @@ struct hw_perf_event {
 	/* Last sync'ed generation of filters */
 	unsigned long			addr_filters_gen;
 
+	/* HW specific configuration */
+	void				*drv_configs;
+
 /*
  * hw_perf_event::state flags; used to track the PERF_EF_* state.
  */

@@ -442,6 +445,12 @@ struct pmu {
 	 * Filter events for PMU-specific reasons.
 	 */
 	int (*filter_match)		(struct perf_event *event); /* optional */
+
+	/*
+	 * PMU driver specific configuration.
+	 */
+	int (*set_drv_configs)		(struct perf_event *event,
+					 void __user *arg); /* optional */
 };
 
 /**

@@ -407,6 +407,7 @@ struct perf_event_attr {
 #define PERF_EVENT_IOC_ID		_IOR('$', 7, __u64 *)
 #define PERF_EVENT_IOC_SET_BPF		_IOW('$', 8, __u32)
 #define PERF_EVENT_IOC_PAUSE_OUTPUT	_IOW('$', 9, __u32)
+#define PERF_EVENT_IOC_SET_DRV_CONFIGS	_IOW('$', 10, char *)
 
 enum perf_event_ioc_flags {
 	PERF_IOC_FLAG_GROUP		= 1U << 0,

@@ -4457,6 +4457,8 @@ static int perf_event_set_output(struct perf_event *event,
 				 struct perf_event *output_event);
 static int perf_event_set_filter(struct perf_event *event, void __user *arg);
 static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd);
+static int perf_event_set_drv_configs(struct perf_event *event,
+				      void __user *arg);
 
 static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg)
 {

@@ -4526,6 +4528,10 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon
 		rcu_read_unlock();
 		return 0;
 	}
+
+	case PERF_EVENT_IOC_SET_DRV_CONFIGS:
+		return perf_event_set_drv_configs(event, (void __user *)arg);
+
 	default:
 		return -ENOTTY;
 	}

@@ -4558,6 +4564,7 @@ static long perf_compat_ioctl(struct file *file, unsigned int cmd,
 	switch (_IOC_NR(cmd)) {
 	case _IOC_NR(PERF_EVENT_IOC_SET_FILTER):
 	case _IOC_NR(PERF_EVENT_IOC_ID):
+	case _IOC_NR(PERF_EVENT_IOC_SET_DRV_CONFIGS):
 		/* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */
 		if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
 			cmd &= ~IOCSIZE_MASK;

@@ -7633,6 +7640,15 @@ void perf_bp_event(struct perf_event *bp, void *data)
 }
 #endif
 
+static int perf_event_set_drv_configs(struct perf_event *event,
+				  void __user *arg)
+{
+	if (!event->pmu->set_drv_configs)
+		return -EINVAL;
+
+	return event->pmu->set_drv_configs(event, arg);
+}
+
 /*
  * Allocate a new address filter
  */

@@ -407,6 +407,7 @@ struct perf_event_attr {
 #define PERF_EVENT_IOC_ID		_IOR('$', 7, __u64 *)
 #define PERF_EVENT_IOC_SET_BPF		_IOW('$', 8, __u32)
 #define PERF_EVENT_IOC_PAUSE_OUTPUT	_IOW('$', 9, __u32)
+#define PERF_EVENT_IOC_SET_DRV_CONFIGS	_IOW('$', 10, char *)
 
 enum perf_event_ioc_flags {
 	PERF_IOC_FLAG_GROUP		= 1U << 0,

@@ -53,16 +53,6 @@ static int str(yyscan_t scanner, int token)
 	return token;
 }
 
-static int drv_str(yyscan_t scanner, int token)
-{
-	YYSTYPE *yylval = parse_events_get_lval(scanner);
-	char *text = parse_events_get_text(scanner);
-
-	/* Strip off the '@' */
-	yylval->str = strdup(text + 1);
-	return token;
-}
-
 #define REWIND(__alloc)				\
 do {								\
 	YYSTYPE *__yylval = parse_events_get_lval(yyscanner);	\

@@ -220,7 +210,7 @@ no-overwrite		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NOOVERWRITE); }
 {name_minus}		{ return str(yyscanner, PE_NAME); }
 \[all\]			{ return PE_ARRAY_ALL; }
 "["			{ BEGIN(array); return '['; }
-@{drv_cfg_term}		{ return drv_str(yyscanner, PE_DRV_CFG_TERM); }
+{drv_cfg_term}		{ return PE_DRV_CFG_TERM; }
 }
 
 <mem>{

@@ -602,12 +602,12 @@ PE_NAME array '=' PE_VALUE
 	$$ = term;
 }
 |
-PE_DRV_CFG_TERM
+'@' PE_DRV_CFG_TERM
 {
 	struct parse_events_term *term;
 
 	ABORT_ON(parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_DRV_CFG,
-					$1, $1, &@1, NULL));
+					$2, $2, &@2, NULL));
 	$$ = term;
 }