--- zzzz-none-000/linux-3.10.107/tools/perf/util/pmu.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/tools/perf/util/pmu.c	2021-02-04 17:41:59.000000000 +0000
@@ -1,21 +1,18 @@
 #include <linux/list.h>
+#include <linux/compiler.h>
 #include <sys/types.h>
-#include <sys/stat.h>
 #include <unistd.h>
 #include <stdio.h>
+#include <stdbool.h>
+#include <stdarg.h>
 #include <dirent.h>
-#include "sysfs.h"
+#include <api/fs/fs.h>
+#include <locale.h>
 #include "util.h"
 #include "pmu.h"
 #include "parse-events.h"
 #include "cpumap.h"
 
-struct perf_pmu_alias {
-	char *name;
-	struct list_head terms;
-	struct list_head list;
-};
-
 struct perf_pmu_format {
 	char *name;
 	int value;
@@ -73,13 +70,12 @@
  * located at:
  * /sys/bus/event_source/devices/<dev>/format as sysfs group attributes.
  */
-static int pmu_format(char *name, struct list_head *format)
+static int pmu_format(const char *name, struct list_head *format)
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return -1;
 
@@ -95,33 +91,190 @@
 	return 0;
 }
 
-static int perf_pmu__new_alias(struct list_head *list, char *name, FILE *file)
+static int perf_pmu__parse_scale(struct perf_pmu_alias *alias, char *dir, char *name)
+{
+	struct stat st;
+	ssize_t sret;
+	char scale[128];
+	int fd, ret = -1;
+	char path[PATH_MAX];
+	const char *lc;
+
+	snprintf(path, PATH_MAX, "%s/%s.scale", dir, name);
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return -1;
+
+	if (fstat(fd, &st) < 0)
+		goto error;
+
+	sret = read(fd, scale, sizeof(scale)-1);
+	if (sret < 0)
+		goto error;
+
+	if (scale[sret - 1] == '\n')
+		scale[sret - 1] = '\0';
+	else
+		scale[sret] = '\0';
+
+	/*
+	 * save current locale
+	 */
+	lc = setlocale(LC_NUMERIC, NULL);
+
+	/*
+	 * force to C locale to ensure kernel
+	 * scale string is converted correctly.
+	 * kernel uses default C locale.
+	 */
+	setlocale(LC_NUMERIC, "C");
+
+	alias->scale = strtod(scale, NULL);
+
+	/* restore locale */
+	setlocale(LC_NUMERIC, lc);
+
+	ret = 0;
+error:
+	close(fd);
+	return ret;
+}
+
+static int perf_pmu__parse_unit(struct perf_pmu_alias *alias, char *dir, char *name)
+{
+	char path[PATH_MAX];
+	ssize_t sret;
+	int fd;
+
+	snprintf(path, PATH_MAX, "%s/%s.unit", dir, name);
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return -1;
+
+		sret = read(fd, alias->unit, UNIT_MAX_LEN);
+	if (sret < 0)
+		goto error;
+
+	close(fd);
+
+	if (alias->unit[sret - 1] == '\n')
+		alias->unit[sret - 1] = '\0';
+	else
+		alias->unit[sret] = '\0';
+
+	return 0;
+error:
+	close(fd);
+	alias->unit[0] = '\0';
+	return -1;
+}
+
+static int
+perf_pmu__parse_per_pkg(struct perf_pmu_alias *alias, char *dir, char *name)
+{
+	char path[PATH_MAX];
+	int fd;
+
+	snprintf(path, PATH_MAX, "%s/%s.per-pkg", dir, name);
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return -1;
+
+	close(fd);
+
+	alias->per_pkg = true;
+	return 0;
+}
+
+static int perf_pmu__parse_snapshot(struct perf_pmu_alias *alias,
+				    char *dir, char *name)
+{
+	char path[PATH_MAX];
+	int fd;
+
+	snprintf(path, PATH_MAX, "%s/%s.snapshot", dir, name);
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return -1;
+
+	alias->snapshot = true;
+	close(fd);
+	return 0;
+}
+
+static int __perf_pmu__new_alias(struct list_head *list, char *dir, char *name,
+				 char *desc __maybe_unused, char *val)
 {
 	struct perf_pmu_alias *alias;
-	char buf[256];
 	int ret;
 
-	ret = fread(buf, 1, sizeof(buf), file);
-	if (ret == 0)
-		return -EINVAL;
-	buf[ret] = 0;
-
 	alias = malloc(sizeof(*alias));
 	if (!alias)
 		return -ENOMEM;
 
 	INIT_LIST_HEAD(&alias->terms);
-	ret = parse_events_terms(&alias->terms, buf);
+	alias->scale = 1.0;
+	alias->unit[0] = '\0';
+	alias->per_pkg = false;
+
+	ret = parse_events_terms(&alias->terms, val);
 	if (ret) {
+		pr_err("Cannot parse alias %s: %d\n", val, ret);
 		free(alias);
 		return ret;
 	}
 
 	alias->name = strdup(name);
+	if (dir) {
+		/*
+		 * load unit name and scale if available
+		 */
+		perf_pmu__parse_unit(alias, dir, name);
+		perf_pmu__parse_scale(alias, dir, name);
+		perf_pmu__parse_per_pkg(alias, dir, name);
+		perf_pmu__parse_snapshot(alias, dir, name);
+	}
+
 	list_add_tail(&alias->list, list);
+
 	return 0;
 }
 
+static int perf_pmu__new_alias(struct list_head *list, char *dir, char *name, FILE *file)
+{
+	char buf[256];
+	int ret;
+
+	ret = fread(buf, 1, sizeof(buf), file);
+	if (ret == 0)
+		return -EINVAL;
+
+	buf[ret] = 0;
+
+	return __perf_pmu__new_alias(list, dir, name, NULL, buf);
+}
+
+static inline bool pmu_alias_info_file(char *name)
+{
+	size_t len;
+
+	len = strlen(name);
+	if (len > 5 && !strcmp(name + len - 5, ".unit"))
+		return true;
+	if (len > 6 && !strcmp(name + len - 6, ".scale"))
+		return true;
+	if (len > 8 && !strcmp(name + len - 8, ".per-pkg"))
+		return true;
+	if (len > 9 && !strcmp(name + len - 9, ".snapshot"))
+		return true;
+
+	return false;
+}
+
 /*
  * Process all the sysfs attributes located under the directory
  * specified in 'dir' parameter.
@@ -130,13 +283,12 @@
 {
 	struct dirent *evt_ent;
 	DIR *event_dir;
-	int ret = 0;
 
 	event_dir = opendir(dir);
 	if (!event_dir)
 		return -EINVAL;
 
-	while (!ret && (evt_ent = readdir(event_dir))) {
+	while ((evt_ent = readdir(event_dir))) {
 		char path[PATH_MAX];
 		char *name = evt_ent->d_name;
 		FILE *file;
@@ -144,31 +296,39 @@
 		if (!strcmp(name, ".") || !strcmp(name, ".."))
 			continue;
 
+		/*
+		 * skip info files parsed in perf_pmu__new_alias()
+		 */
+		if (pmu_alias_info_file(name))
+			continue;
+
 		snprintf(path, PATH_MAX, "%s/%s", dir, name);
 
-		ret = -EINVAL;
 		file = fopen(path, "r");
-		if (!file)
-			break;
-		ret = perf_pmu__new_alias(head, name, file);
+		if (!file) {
+			pr_debug("Cannot open %s\n", path);
+			continue;
+		}
+
+		if (perf_pmu__new_alias(head, dir, name, file) < 0)
+			pr_debug("Cannot set up %s\n", name);
 		fclose(file);
 	}
 
 	closedir(event_dir);
-	return ret;
+	return 0;
 }
 
 /*
  * Reading the pmu event aliases definition, which should be located at:
  * /sys/bus/event_source/devices/<dev>/events as sysfs group attributes.
  */
-static int pmu_aliases(char *name, struct list_head *head)
+static int pmu_aliases(const char *name, struct list_head *head)
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return -1;
 
@@ -187,17 +347,17 @@
 static int pmu_alias_terms(struct perf_pmu_alias *alias,
 			   struct list_head *terms)
 {
-	struct parse_events_term *term, *clone;
+	struct parse_events_term *term, *cloned;
 	LIST_HEAD(list);
 	int ret;
 
 	list_for_each_entry(term, &alias->terms, list) {
-		ret = parse_events_term__clone(&clone, term);
+		ret = parse_events_term__clone(&cloned, term);
 		if (ret) {
 			parse_events__free_terms(&list);
 			return ret;
 		}
-		list_add_tail(&clone->list, &list);
+		list_add_tail(&cloned->list, &list);
 	}
 	list_splice(&list, terms);
 	return 0;
@@ -208,15 +368,14 @@
  * located at:
  * /sys/bus/event_source/devices/<dev>/type as sysfs attribute.
  */
-static int pmu_type(char *name, __u32 *type)
+static int pmu_type(const char *name, __u32 *type)
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
 	FILE *file;
 	int ret = 0;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return -1;
 
@@ -241,11 +400,10 @@
 static void pmu_read_sysfs(void)
 {
 	char path[PATH_MAX];
-	const char *sysfs;
 	DIR *dir;
 	struct dirent *dent;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return;
 
@@ -266,15 +424,14 @@
 	closedir(dir);
 }
 
-static struct cpu_map *pmu_cpumask(char *name)
+static struct cpu_map *pmu_cpumask(const char *name)
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
 	FILE *file;
 	struct cpu_map *cpus;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return NULL;
 
@@ -293,7 +450,13 @@
 	return cpus;
 }
 
-static struct perf_pmu *pmu_lookup(char *name)
+struct perf_event_attr * __weak
+perf_pmu__get_default_config(struct perf_pmu *pmu __maybe_unused)
+{
+	return NULL;
+}
+
+static struct perf_pmu *pmu_lookup(const char *name)
 {
 	struct perf_pmu *pmu;
 	LIST_HEAD(format);
@@ -327,10 +490,13 @@
 	pmu->name = strdup(name);
 	pmu->type = type;
 	list_add_tail(&pmu->list, &pmus);
+
+	pmu->default_config = perf_pmu__get_default_config(pmu);
+
 	return pmu;
 }
 
-static struct perf_pmu *pmu_find(char *name)
+static struct perf_pmu *pmu_find(const char *name)
 {
 	struct perf_pmu *pmu;
 
@@ -356,7 +522,7 @@
 	return NULL;
 }
 
-struct perf_pmu *perf_pmu__find(char *name)
+struct perf_pmu *perf_pmu__find(const char *name)
 {
 	struct perf_pmu *pmu;
 
@@ -373,7 +539,7 @@
 }
 
 static struct perf_pmu_format *
-pmu_find_format(struct list_head *formats, char *name)
+pmu_find_format(struct list_head *formats, const char *name)
 {
 	struct perf_pmu_format *format;
 
@@ -384,56 +550,147 @@
 	return NULL;
 }
 
+__u64 perf_pmu__format_bits(struct list_head *formats, const char *name)
+{
+	struct perf_pmu_format *format = pmu_find_format(formats, name);
+	__u64 bits = 0;
+	int fbit;
+
+	if (!format)
+		return 0;
+
+	for_each_set_bit(fbit, format->bits, PERF_PMU_FORMAT_BITS)
+		bits |= 1ULL << fbit;
+
+	return bits;
+}
+
 /*
- * Returns value based on the format definition (format parameter)
+ * Sets value based on the format definition (format parameter)
  * and unformated value (value parameter).
- *
- * TODO maybe optimize a little ;)
  */
-static __u64 pmu_format_value(unsigned long *format, __u64 value)
+static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
+			     bool zero)
 {
 	unsigned long fbit, vbit;
-	__u64 v = 0;
 
 	for (fbit = 0, vbit = 0; fbit < PERF_PMU_FORMAT_BITS; fbit++) {
 
 		if (!test_bit(fbit, format))
 			continue;
 
-		if (!(value & (1llu << vbit++)))
-			continue;
+		if (value & (1llu << vbit++))
+			*v |= (1llu << fbit);
+		else if (zero)
+			*v &= ~(1llu << fbit);
+	}
+}
 
-		v |= (1llu << fbit);
+static __u64 pmu_format_max_value(const unsigned long *format)
+{
+	int w;
+
+	w = bitmap_weight(format, PERF_PMU_FORMAT_BITS);
+	if (!w)
+		return 0;
+	if (w < 64)
+		return (1ULL << w) - 1;
+	return -1;
+}
+
+/*
+ * Term is a string term, and might be a param-term. Try to look up it's value
+ * in the remaining terms.
+ * - We have a term like "base-or-format-term=param-term",
+ * - We need to find the value supplied for "param-term" (with param-term named
+ *   in a config string) later on in the term list.
+ */
+static int pmu_resolve_param_term(struct parse_events_term *term,
+				  struct list_head *head_terms,
+				  __u64 *value)
+{
+	struct parse_events_term *t;
+
+	list_for_each_entry(t, head_terms, list) {
+		if (t->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
+			if (!strcmp(t->config, term->config)) {
+				t->used = true;
+				*value = t->val.num;
+				return 0;
+			}
+		}
 	}
 
-	return v;
+	if (verbose)
+		printf("Required parameter '%s' not specified\n", term->config);
+
+	return -1;
+}
+
+static char *pmu_formats_string(struct list_head *formats)
+{
+	struct perf_pmu_format *format;
+	char *str;
+	struct strbuf buf;
+	unsigned i = 0;
+
+	if (!formats)
+		return NULL;
+
+	strbuf_init(&buf, 0);
+	/* sysfs exported terms */
+	list_for_each_entry(format, formats, list)
+		strbuf_addf(&buf, i++ ? ",%s" : "%s",
+			    format->name);
+
+	str = strbuf_detach(&buf, NULL);
+	strbuf_release(&buf);
+
+	return str;
 }
 
 /*
  * Setup one of config[12] attr members based on the
- * user input data - temr parameter.
+ * user input data - term parameter.
  */
 static int pmu_config_term(struct list_head *formats,
 			   struct perf_event_attr *attr,
-			   struct parse_events_term *term)
+			   struct parse_events_term *term,
+			   struct list_head *head_terms,
+			   bool zero, struct parse_events_error *err)
 {
 	struct perf_pmu_format *format;
 	__u64 *vp;
+	__u64 val, max_val;
+
+	/*
+	 * If this is a parameter we've already used for parameterized-eval,
+	 * skip it in normal eval.
+	 */
+	if (term->used)
+		return 0;
 
 	/*
-	 * Support only for hardcoded and numnerial terms.
 	 * Hardcoded terms should be already in, so nothing
 	 * to be done for them.
 	 */
 	if (parse_events__is_hardcoded_term(term))
 		return 0;
 
-	if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM)
-		return -EINVAL;
-
 	format = pmu_find_format(formats, term->config);
-	if (!format)
+	if (!format) {
+		if (verbose)
+			printf("Invalid event/parameter '%s'\n", term->config);
+		if (err) {
+			char *pmu_term = pmu_formats_string(formats);
+
+			err->idx  = term->err_term;
+			err->str  = strdup("unknown term");
+			err->help = parse_events_formats_error_string(pmu_term);
+			free(pmu_term);
+		}
 		return -EINVAL;
+	}
 
 	switch (format->value) {
 	case PERF_PMU_FORMAT_VALUE_CONFIG:
@@ -450,23 +707,61 @@
 	}
 
 	/*
-	 * XXX If we ever decide to go with string values for
-	 * non-hardcoded terms, here's the place to translate
-	 * them into value.
+	 * Either directly use a numeric term, or try to translate string terms
+	 * using event parameters.
 	 */
-	*vp |= pmu_format_value(format->bits, term->val.num);
+	if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
+		val = term->val.num;
+	else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
+		if (strcmp(term->val.str, "?")) {
+			if (verbose) {
+				pr_info("Invalid sysfs entry %s=%s\n",
+						term->config, term->val.str);
+			}
+			if (err) {
+				err->idx = term->err_val;
+				err->str = strdup("expected numeric value");
+			}
+			return -EINVAL;
+		}
+
+		if (pmu_resolve_param_term(term, head_terms, &val))
+			return -EINVAL;
+	} else
+		return -EINVAL;
+
+	max_val = pmu_format_max_value(format->bits);
+	if (val > max_val) {
+		if (err) {
+			err->idx = term->err_val;
+			if (asprintf(&err->str,
+				     "value too big for format, maximum is %llu",
+				     (unsigned long long)max_val) < 0)
+				err->str = strdup("value too big for format");
+			return -EINVAL;
+		}
+		/*
+		 * Assume we don't care if !err, in which case the value will be
+		 * silently truncated.
+		 */
+	}
+
+	pmu_format_value(format->bits, val, vp, zero);
 	return 0;
 }
 
 int perf_pmu__config_terms(struct list_head *formats,
 			   struct perf_event_attr *attr,
-			   struct list_head *head_terms)
+			   struct list_head *head_terms,
+			   bool zero, struct parse_events_error *err)
 {
 	struct parse_events_term *term;
 
-	list_for_each_entry(term, head_terms, list)
-		if (pmu_config_term(formats, attr, term))
+	list_for_each_entry(term, head_terms, list) {
+		if (pmu_config_term(formats, attr, term, head_terms,
+				    zero, err))
 			return -EINVAL;
+	}
 
 	return 0;
 }
@@ -477,10 +772,14 @@
  * 2) pmu format definitions - specified by pmu parameter
  */
 int perf_pmu__config(struct perf_pmu *pmu, struct perf_event_attr *attr,
-		     struct list_head *head_terms)
+		     struct list_head *head_terms,
+		     struct parse_events_error *err)
 {
+	bool zero = !!pmu->default_config;
+
 	attr->type = pmu->type;
-	return perf_pmu__config_terms(&pmu->format, attr, head_terms);
+	return perf_pmu__config_terms(&pmu->format, attr, head_terms,
+				      zero, err);
 }
 
 static struct perf_pmu_alias *pmu_find_alias(struct perf_pmu *pmu,
@@ -513,16 +812,53 @@
 	return NULL;
 }
 
+
+static int check_info_data(struct perf_pmu_alias *alias,
+			   struct perf_pmu_info *info)
+{
+	/*
+	 * Only one term in event definition can
+	 * define unit, scale and snapshot, fail
+	 * if there's more than one.
+	 */
+	if ((info->unit && alias->unit) ||
+	    (info->scale && alias->scale) ||
+	    (info->snapshot && alias->snapshot))
+		return -EINVAL;
+
+	if (alias->unit)
+		info->unit = alias->unit;
+
+	if (alias->scale)
+		info->scale = alias->scale;
+
+	if (alias->snapshot)
+		info->snapshot = alias->snapshot;
+
+	return 0;
+}
+
 /*
  * Find alias in the terms list and replace it with the terms
  * defined for the alias
  */
-int perf_pmu__check_alias(struct perf_pmu *pmu, struct list_head *head_terms)
+int perf_pmu__check_alias(struct perf_pmu *pmu, struct list_head *head_terms,
+			  struct perf_pmu_info *info)
 {
 	struct parse_events_term *term, *h;
 	struct perf_pmu_alias *alias;
 	int ret;
 
+	info->per_pkg = false;
+
+	/*
+	 * Mark unit and scale as not set
+	 * (different from default values, see below)
+	 */
+	info->unit     = NULL;
+	info->scale    = 0.0;
+	info->snapshot = false;
+
 	list_for_each_entry_safe(term, h, head_terms, list) {
 		alias = pmu_find_alias(pmu, term);
 		if (!alias)
@@ -530,9 +866,29 @@
 		ret = pmu_alias_terms(alias, &term->list);
 		if (ret)
 			return ret;
+
+		ret = check_info_data(alias, info);
+		if (ret)
+			return ret;
+
+		if (alias->per_pkg)
+			info->per_pkg = true;
+
 		list_del(&term->list);
 		free(term);
 	}
+
+	/*
+	 * if no unit or scale foundin aliases, then
+	 * set defaults as for evsel
+	 * unit cannot left to NULL
+	 */
+	if (info->unit == NULL)
+		info->unit   = "";
+
+	if (info->scale == 0.0)
+		info->scale  = 1.0;
+
 	return 0;
 }
 
@@ -564,3 +920,176 @@
 	for (b = from; b <= to; b++)
 		set_bit(b, bits);
 }
+
+static int sub_non_neg(int a, int b)
+{
+	if (b > a)
+		return 0;
+	return a - b;
+}
+
+static char *format_alias(char *buf, int len, struct perf_pmu *pmu,
+			  struct perf_pmu_alias *alias)
+{
+	struct parse_events_term *term;
+	int used = snprintf(buf, len, "%s/%s", pmu->name, alias->name);
+
+	list_for_each_entry(term, &alias->terms, list) {
+		if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
+			used += snprintf(buf + used, sub_non_neg(len, used),
+					",%s=%s", term->config,
+					term->val.str);
+	}
+
+	if (sub_non_neg(len, used) > 0) {
+		buf[used] = '/';
+		used++;
+	}
+	if (sub_non_neg(len, used) > 0) {
+		buf[used] = '\0';
+		used++;
+	} else
+		buf[len - 1] = '\0';
+
+	return buf;
+}
+
+static char *format_alias_or(char *buf, int len, struct perf_pmu *pmu,
+			     struct perf_pmu_alias *alias)
+{
+	snprintf(buf, len, "%s OR %s/%s/", alias->name, pmu->name, alias->name);
+	return buf;
+}
+
+static int cmp_string(const void *a, const void *b)
+{
+	const char * const *as = a;
+	const char * const *bs = b;
+	return strcmp(*as, *bs);
+}
+
+void print_pmu_events(const char *event_glob, bool name_only)
+{
+	struct perf_pmu *pmu;
+	struct perf_pmu_alias *alias;
+	char buf[1024];
+	int printed = 0;
+	int len, j;
+	char **aliases;
+
+	pmu = NULL;
+	len = 0;
+	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
+		list_for_each_entry(alias, &pmu->aliases, list)
+			len++;
+		if (pmu->selectable)
+			len++;
+	}
+	aliases = zalloc(sizeof(char *) * len);
+	if (!aliases)
+		goto out_enomem;
+	pmu = NULL;
+	j = 0;
+	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
+		list_for_each_entry(alias, &pmu->aliases, list) {
+			char *name = format_alias(buf, sizeof(buf), pmu, alias);
+			bool is_cpu = !strcmp(pmu->name, "cpu");
+
+			if (event_glob != NULL &&
+			    !(strglobmatch(name, event_glob) ||
+			      (!is_cpu && strglobmatch(alias->name,
+						       event_glob))))
+				continue;
+
+			if (is_cpu && !name_only)
+				name = format_alias_or(buf, sizeof(buf), pmu, alias);
+
+			aliases[j] = strdup(name);
+			if (aliases[j] == NULL)
+				goto out_enomem;
+			j++;
+		}
+		if (pmu->selectable &&
+		    (event_glob == NULL || strglobmatch(pmu->name, event_glob))) {
+			char *s;
+			if (asprintf(&s, "%s//", pmu->name) < 0)
+				goto out_enomem;
+			aliases[j] = s;
+			j++;
+		}
+	}
+	len = j;
+	qsort(aliases, len, sizeof(char *), cmp_string);
+	for (j = 0; j < len; j++) {
+		if (name_only) {
+			printf("%s ", aliases[j]);
+			continue;
+		}
+		printf("  %-50s [Kernel PMU event]\n", aliases[j]);
+		printed++;
+	}
+	if (printed && pager_in_use())
+		printf("\n");
+out_free:
+	for (j = 0; j < len; j++)
+		zfree(&aliases[j]);
+	zfree(&aliases);
+	return;
+
+out_enomem:
+	printf("FATAL: not enough memory to print PMU events\n");
+	if (aliases)
+		goto out_free;
+}
+
+bool pmu_have_event(const char *pname, const char *name)
+{
+	struct perf_pmu *pmu;
+	struct perf_pmu_alias *alias;
+
+	pmu = NULL;
+	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
+		if (strcmp(pname, pmu->name))
+			continue;
+		list_for_each_entry(alias, &pmu->aliases, list)
+			if (!strcmp(alias->name, name))
+				return true;
+	}
+	return false;
+}
+
+static FILE *perf_pmu__open_file(struct perf_pmu *pmu, const char *name)
+{
+	struct stat st;
+	char path[PATH_MAX];
+	const char *sysfs;
+
+	sysfs = sysfs__mountpoint();
+	if (!sysfs)
+		return NULL;
+
+	snprintf(path, PATH_MAX,
+		 "%s" EVENT_SOURCE_DEVICE_PATH "%s/%s", sysfs, pmu->name, name);
+
+	if (stat(path, &st) < 0)
+		return NULL;
+
+	return fopen(path, "r");
+}
+
+int perf_pmu__scan_file(struct perf_pmu *pmu, const char *name, const char *fmt,
+			...)
+{
+	va_list args;
+	FILE *file;
+	int ret = EOF;
+
+	va_start(args, fmt);
+	file = perf_pmu__open_file(pmu, name);
+	if (file) {
+		ret = vfscanf(file, fmt, args);
+		fclose(file);
+	}
+	va_end(args);
+	return ret;
+}