pmu.c

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// SPDX-License-Identifier: GPL-2.0
#include <linux/list.h>
#include <linux/compiler.h>
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdbool.h>
#include <stdarg.h>
#include <dirent.h>
#include <api/fs/fs.h>
#include <locale.h>
#include <regex.h>
#include "util.h"
#include "pmu.h"
#include "parse-events.h"
#include "cpumap.h"
#include "header.h"
#include "pmu-events/pmu-events.h"
#include "cache.h"
#include "string2.h"

struct perf_pmu_format {
    char *name;
    int value;
    DECLARE_BITMAP(bits, PERF_PMU_FORMAT_BITS);
    struct list_head list;
};

#define EVENT_SOURCE_DEVICE_PATH "/bus/event_source/devices/"

int perf_pmu_parse(struct list_head *list, char *name);
extern FILE *perf_pmu_in;

static LIST_HEAD(pmus);

/*
 * Parse & process all the sysfs attributes located under
 * the directory specified in 'dir' parameter.
 */
int perf_pmu__format_parse(char *dir, struct list_head *head)
{
    struct dirent *evt_ent;
    DIR *format_dir;
    int ret = 0;

    format_dir = opendir(dir);
    if (!format_dir)
        return -EINVAL;

    while (!ret && (evt_ent = readdir(format_dir))) {
        char path[PATH_MAX];
        char *name = evt_ent->d_name;
        FILE *file;

        if (!strcmp(name, ".") || !strcmp(name, ".."))
            continue;

        snprintf(path, PATH_MAX, "%s/%s", dir, name);

        ret = -EINVAL;
        file = fopen(path, "r");
        if (!file)
            break;

        perf_pmu_in = file;
        ret = perf_pmu_parse(head, name);
        fclose(file);
    }

    closedir(format_dir);
    return ret;
}

/*
 * Reading/parsing the default pmu format definition, which should be
 * located at:
 * /sys/bus/event_source/devices/<dev>/format as sysfs group attributes.
 */
static int pmu_format(const char *name, struct list_head *format)
{
    struct stat st;
    char path[PATH_MAX];
    const char *sysfs = sysfs__mountpoint();

    if (!sysfs)
        return -1;

    snprintf(path, PATH_MAX,
         "%s" EVENT_SOURCE_DEVICE_PATH "%s/format", sysfs, name);

    if (stat(path, &st) < 0)
        return 0;   /* no error if format does not exist */

    if (perf_pmu__format_parse(path, format))
        return -1;

    return 0;
}

static int convert_scale(const char *scale, char **end, double *sval)
{
    char *lc;
    int ret = 0;

    /*
     * save current locale
     */
    lc = setlocale(LC_NUMERIC, NULL);

    /*
     * The lc string may be allocated in static storage,
     * so get a dynamic copy to make it survive setlocale
     * call below.
     */
    lc = strdup(lc);
    if (!lc) {
        ret = -ENOMEM;
        goto out;
    }

    /*
     * force to C locale to ensure kernel
     * scale string is converted correctly.
     * kernel uses default C locale.
     */
    setlocale(LC_NUMERIC, "C");

    *sval = strtod(scale, end);

out:
    /* restore locale */
    setlocale(LC_NUMERIC, lc);
    free(lc);
    return ret;
}

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];

    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';

    ret = convert_scale(scale, NULL, &alias->scale);
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, char *val,
                 char *long_desc, char *topic,
                 char *unit, char *perpkg,
                 char *metric_expr,
                 char *metric_name)
{
    struct perf_pmu_alias *alias;
    int ret;
    int num;

    alias = malloc(sizeof(*alias));
    if (!alias)
        return -ENOMEM;

    INIT_LIST_HEAD(&alias->terms);
    alias->scale = 1.0;
    alias->unit[0] = '\0';
    alias->per_pkg = false;
    alias->snapshot = 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);
    }

    alias->metric_expr = metric_expr ? strdup(metric_expr) : NULL;
    alias->metric_name = metric_name ? strdup(metric_name): NULL;
    alias->desc = desc ? strdup(desc) : NULL;
    alias->long_desc = long_desc ? strdup(long_desc) :
                desc ? strdup(desc) : NULL;
    alias->topic = topic ? strdup(topic) : NULL;
    if (unit) {
        if (convert_scale(unit, &unit, &alias->scale) < 0)
            return -1;
        snprintf(alias->unit, sizeof(alias->unit), "%s", unit);
    }
    alias->per_pkg = perpkg && sscanf(perpkg, "%d", &num) == 1 && num == 1;
    alias->str = strdup(val);

    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, NULL, NULL, NULL,
                     NULL, NULL, NULL);
}

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.
 */
static int pmu_aliases_parse(char *dir, struct list_head *head)
{
    struct dirent *evt_ent;
    DIR *event_dir;

    event_dir = opendir(dir);
    if (!event_dir)
        return -EINVAL;

    while ((evt_ent = readdir(event_dir))) {
        char path[PATH_MAX];
        char *name = evt_ent->d_name;
        FILE *file;

        if (!strcmp(name, ".") || !strcmp(name, ".."))
            continue;

        /*
         * skip info files parsed in perf_pmu__new_alias()
         */
        if (pmu_alias_info_file(name))
            continue;

        scnprintf(path, PATH_MAX, "%s/%s", dir, name);

        file = fopen(path, "r");
        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 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(const char *name, struct list_head *head)
{
    struct stat st;
    char path[PATH_MAX];
    const char *sysfs = sysfs__mountpoint();

    if (!sysfs)
        return -1;

    snprintf(path, PATH_MAX,
         "%s/bus/event_source/devices/%s/events", sysfs, name);

    if (stat(path, &st) < 0)
        return 0;    /* no error if 'events' does not exist */

    if (pmu_aliases_parse(path, head))
        return -1;

    return 0;
}

static int pmu_alias_terms(struct perf_pmu_alias *alias,
               struct list_head *terms)
{
    struct parse_events_term *term, *cloned;
    LIST_HEAD(list);
    int ret;

    list_for_each_entry(term, &alias->terms, list) {
        ret = parse_events_term__clone(&cloned, term);
        if (ret) {
            parse_events_terms__purge(&list);
            return ret;
        }
        /*
         * Weak terms don't override command line options,
         * which we don't want for implicit terms in aliases.
         */
        cloned->weak = true;
        list_add_tail(&cloned->list, &list);
    }
    list_splice(&list, terms);
    return 0;
}

/*
 * Reading/parsing the default pmu type value, which should be
 * located at:
 * /sys/bus/event_source/devices/<dev>/type as sysfs attribute.
 */
static int pmu_type(const char *name, __u32 *type)
{
    struct stat st;
    char path[PATH_MAX];
    FILE *file;
    int ret = 0;
    const char *sysfs = sysfs__mountpoint();

    if (!sysfs)
        return -1;

    snprintf(path, PATH_MAX,
         "%s" EVENT_SOURCE_DEVICE_PATH "%s/type", sysfs, name);

    if (stat(path, &st) < 0)
        return -1;

    file = fopen(path, "r");
    if (!file)
        return -EINVAL;

    if (1 != fscanf(file, "%u", type))
        ret = -1;

    fclose(file);
    return ret;
}

/* Add all pmus in sysfs to pmu list: */
static void pmu_read_sysfs(void)
{
    char path[PATH_MAX];
    DIR *dir;
    struct dirent *dent;
    const char *sysfs = sysfs__mountpoint();

    if (!sysfs)
        return;

    snprintf(path, PATH_MAX,
         "%s" EVENT_SOURCE_DEVICE_PATH, sysfs);

    dir = opendir(path);
    if (!dir)
        return;

    while ((dent = readdir(dir))) {
        if (!strcmp(dent->d_name, ".") || !strcmp(dent->d_name, ".."))
            continue;
        /* add to static LIST_HEAD(pmus): */
        perf_pmu__find(dent->d_name);
    }

    closedir(dir);
}

static struct cpu_map *__pmu_cpumask(const char *path)
{
    FILE *file;
    struct cpu_map *cpus;

    file = fopen(path, "r");
    if (!file)
        return NULL;

    cpus = cpu_map__read(file);
    fclose(file);
    return cpus;
}

/*
 * Uncore PMUs have a "cpumask" file under sysfs. CPU PMUs (e.g. on arm/arm64)
 * may have a "cpus" file.
 */
#define CPUS_TEMPLATE_UNCORE    "%s/bus/event_source/devices/%s/cpumask"
#define CPUS_TEMPLATE_CPU   "%s/bus/event_source/devices/%s/cpus"

static struct cpu_map *pmu_cpumask(const char *name)
{
    char path[PATH_MAX];
    struct cpu_map *cpus;
    const char *sysfs = sysfs__mountpoint();
    const char *templates[] = {
        CPUS_TEMPLATE_UNCORE,
        CPUS_TEMPLATE_CPU,
        NULL
    };
    const char **template;

    if (!sysfs)
        return NULL;

    for (template = templates; *template; template++) {
        snprintf(path, PATH_MAX, *template, sysfs, name);
        cpus = __pmu_cpumask(path);
        if (cpus)
            return cpus;
    }

    return NULL;
}

static bool pmu_is_uncore(const char *name)
{
    char path[PATH_MAX];
    struct cpu_map *cpus;
    const char *sysfs = sysfs__mountpoint();

    snprintf(path, PATH_MAX, CPUS_TEMPLATE_UNCORE, sysfs, name);
    cpus = __pmu_cpumask(path);
    cpu_map__put(cpus);

    return !!cpus;
}

/*
 *  PMU CORE devices have different name other than cpu in sysfs on some
 *  platforms.
 *  Looking for possible sysfs files to identify the arm core device.
 */
static int is_arm_pmu_core(const char *name)
{
    struct stat st;
    char path[PATH_MAX];
    const char *sysfs = sysfs__mountpoint();

    if (!sysfs)
        return 0;

    /* Look for cpu sysfs (specific to arm) */
    scnprintf(path, PATH_MAX, "%s/bus/event_source/devices/%s/cpus",
                sysfs, name);
    if (stat(path, &st) == 0)
        return 1;

    /* Look for cpu sysfs (specific to s390) */
    scnprintf(path, PATH_MAX, "%s/bus/event_source/devices/%s",
          sysfs, name);
    if (stat(path, &st) == 0 && !strncmp(name, "cpum_", 5))
        return 1;

    return 0;
}

/*
 * Return the CPU id as a raw string.
 *
 * Each architecture should provide a more precise id string that
 * can be use to match the architecture's "mapfile".
 */
char * __weak get_cpuid_str(struct perf_pmu *pmu __maybe_unused)
{
    return NULL;
}

/* Return zero when the cpuid from the mapfile.csv matches the
 * cpuid string generated on this platform.
 * Otherwise return non-zero.
 */
int strcmp_cpuid_str(const char *mapcpuid, const char *cpuid)
{
    regex_t re;
    regmatch_t pmatch[1];
    int match;

    if (regcomp(&re, mapcpuid, REG_EXTENDED) != 0) {
        /* Warn unable to generate match particular string. */
        pr_info("Invalid regular expression %s\n", mapcpuid);
        return 1;
    }

    match = !regexec(&re, cpuid, 1, pmatch, 0);
    regfree(&re);
    if (match) {
        size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so);

        /* Verify the entire string matched. */
        if (match_len == strlen(cpuid))
            return 0;
    }
    return 1;
}

static char *perf_pmu__getcpuid(struct perf_pmu *pmu)
{
    char *cpuid;
    static bool printed;

    cpuid = getenv("PERF_CPUID");
    if (cpuid)
        cpuid = strdup(cpuid);
    if (!cpuid)
        cpuid = get_cpuid_str(pmu);
    if (!cpuid)
        return NULL;

    if (!printed) {
        pr_debug("Using CPUID %s\n", cpuid);
        printed = true;
    }
    return cpuid;
}

struct pmu_events_map *perf_pmu__find_map(struct perf_pmu *pmu)
{
    struct pmu_events_map *map;
    char *cpuid = perf_pmu__getcpuid(pmu);
    int i;

    /* on some platforms which uses cpus map, cpuid can be NULL for
     * PMUs other than CORE PMUs.
     */
    if (!cpuid)
        return NULL;

    i = 0;
    for (;;) {
        map = &pmu_events_map[i++];
        if (!map->table) {
            map = NULL;
            break;
        }

        if (!strcmp_cpuid_str(map->cpuid, cpuid))
            break;
    }
    free(cpuid);
    return map;
}

/*
 * From the pmu_events_map, find the table of PMU events that corresponds
 * to the current running CPU. Then, add all PMU events from that table
 * as aliases.
 */
static void pmu_add_cpu_aliases(struct list_head *head, struct perf_pmu *pmu)
{
    int i;
    struct pmu_events_map *map;
    struct pmu_event *pe;
    const char *name = pmu->name;
    const char *pname;

    map = perf_pmu__find_map(pmu);
    if (!map)
        return;

    /*
     * Found a matching PMU events table. Create aliases
     */
    i = 0;
    while (1) {

        pe = &map->table[i++];
        if (!pe->name) {
            if (pe->metric_group || pe->metric_name)
                continue;
            break;
        }

        if (!is_arm_pmu_core(name)) {
            pname = pe->pmu ? pe->pmu : "cpu";
            if (strncmp(pname, name, strlen(pname)))
                continue;
        }

        /* need type casts to override 'const' */
        __perf_pmu__new_alias(head, NULL, (char *)pe->name,
                (char *)pe->desc, (char *)pe->event,
                (char *)pe->long_desc, (char *)pe->topic,
                (char *)pe->unit, (char *)pe->perpkg,
                (char *)pe->metric_expr,
                (char *)pe->metric_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);
    LIST_HEAD(aliases);
    __u32 type;

    /*
     * The pmu data we store & need consists of the pmu
     * type value and format definitions. Load both right
     * now.
     */
    if (pmu_format(name, &format))
        return NULL;

    /*
     * Check the type first to avoid unnecessary work.
     */
    if (pmu_type(name, &type))
        return NULL;

    if (pmu_aliases(name, &aliases))
        return NULL;

    pmu = zalloc(sizeof(*pmu));
    if (!pmu)
        return NULL;

    pmu->cpus = pmu_cpumask(name);
    pmu->name = strdup(name);
    pmu->type = type;
    pmu->is_uncore = pmu_is_uncore(name);
    pmu_add_cpu_aliases(&aliases, pmu);

    INIT_LIST_HEAD(&pmu->format);
    INIT_LIST_HEAD(&pmu->aliases);
    list_splice(&format, &pmu->format);
    list_splice(&aliases, &pmu->aliases);
    list_add_tail(&pmu->list, &pmus);

    pmu->default_config = perf_pmu__get_default_config(pmu);

    return pmu;
}

static struct perf_pmu *pmu_find(const char *name)
{
    struct perf_pmu *pmu;

    list_for_each_entry(pmu, &pmus, list)
        if (!strcmp(pmu->name, name))
            return pmu;

    return NULL;
}

struct perf_pmu *perf_pmu__scan(struct perf_pmu *pmu)
{
    /*
     * pmu iterator: If pmu is NULL, we start at the begin,
     * otherwise return the next pmu. Returns NULL on end.
     */
    if (!pmu) {
        pmu_read_sysfs();
        pmu = list_prepare_entry(pmu, &pmus, list);
    }
    list_for_each_entry_continue(pmu, &pmus, list)
        return pmu;
    return NULL;
}

struct perf_pmu *perf_pmu__find(const char *name)
{
    struct perf_pmu *pmu;

    /*
     * Once PMU is loaded it stays in the list,
     * so we keep us from multiple reading/parsing
     * the pmu format definitions.
     */
    pmu = pmu_find(name);
    if (pmu)
        return pmu;

    return pmu_lookup(name);
}

static struct perf_pmu_format *
pmu_find_format(struct list_head *formats, const char *name)
{
    struct perf_pmu_format *format;

    list_for_each_entry(format, formats, list)
        if (!strcmp(format->name, name))
            return format;

    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;
}

/*
 * Sets value based on the format definition (format parameter)
 * and unformated value (value parameter).
 */
static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
                 bool zero)
{
    unsigned long fbit, vbit;

    for (fbit = 0, vbit = 0; fbit < PERF_PMU_FORMAT_BITS; fbit++) {

        if (!test_bit(fbit, format))
            continue;

        if (value & (1llu << vbit++))
            *v |= (1llu << fbit);
        else if (zero)
            *v &= ~(1llu << fbit);
    }
}

static __u64 pmu_format_max_value(const unsigned long *format)
{
    __u64 w = 0;
    int fbit;

    for_each_set_bit(fbit, format, PERF_PMU_FORMAT_BITS)
        w |= (1ULL << fbit);

    return w;
}

/*
 * 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;
            }
        }
    }

    if (verbose > 0)
        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 = NULL;
    struct strbuf buf = STRBUF_INIT;
    unsigned i = 0;

    if (!formats)
        return NULL;

    /* sysfs exported terms */
    list_for_each_entry(format, formats, list)
        if (strbuf_addf(&buf, i++ ? ",%s" : "%s", format->name) < 0)
            goto error;

    str = strbuf_detach(&buf, NULL);
error:
    strbuf_release(&buf);

    return str;
}

/*
 * Setup one of config[12] attr members based on the
 * 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 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;

    /*
     * Hardcoded terms should be already in, so nothing
     * to be done for them.
     */
    if (parse_events__is_hardcoded_term(term))
        return 0;

    format = pmu_find_format(formats, term->config);
    if (!format) {
        if (verbose > 0)
            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:
        vp = &attr->config;
        break;
    case PERF_PMU_FORMAT_VALUE_CONFIG1:
        vp = &attr->config1;
        break;
    case PERF_PMU_FORMAT_VALUE_CONFIG2:
        vp = &attr->config2;
        break;
    default:
        return -EINVAL;
    }

    /*
     * Either directly use a numeric term, or try to translate string terms
     * using event parameters.
     */
    if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
        if (term->no_value &&
            bitmap_weight(format->bits, PERF_PMU_FORMAT_BITS) > 1) {
            if (err) {
                err->idx = term->err_val;
                err->str = strdup("no value assigned for term");
            }
            return -EINVAL;
        }

        val = term->val.num;
    } else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
        if (strcmp(term->val.str, "?")) {
            if (verbose > 0) {
                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,
               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, head_terms,
                    zero, err))
            return -EINVAL;
    }

    return 0;
}

/*
 * Configures event's 'attr' parameter based on the:
 * 1) users input - specified in terms parameter
 * 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 parse_events_error *err)
{
    bool zero = !!pmu->default_config;

    attr->type = pmu->type;
    return perf_pmu__config_terms(&pmu->format, attr, head_terms,
                      zero, err);
}

static struct perf_pmu_alias *pmu_find_alias(struct perf_pmu *pmu,
                         struct parse_events_term *term)
{
    struct perf_pmu_alias *alias;
    char *name;

    if (parse_events__is_hardcoded_term(term))
        return NULL;

    if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
        if (term->val.num != 1)
            return NULL;
        if (pmu_find_format(&pmu->format, term->config))
            return NULL;
        name = term->config;
    } else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
        if (strcasecmp(term->config, "event"))
            return NULL;
        name = term->val.str;
    } else {
        return NULL;
    }

    list_for_each_entry(alias, &pmu->aliases, list) {
        if (!strcasecmp(alias->name, name))
            return alias;
    }
    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[0]) ||
        (info->scale && alias->scale) ||
        (info->snapshot && alias->snapshot))
        return -EINVAL;

    if (alias->unit[0])
        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,
              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;
    info->metric_expr = NULL;
    info->metric_name = NULL;

    list_for_each_entry_safe(term, h, head_terms, list) {
        alias = pmu_find_alias(pmu, term);
        if (!alias)
            continue;
        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;
        info->metric_expr = alias->metric_expr;
        info->metric_name = alias->metric_name;

        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;
}

int perf_pmu__new_format(struct list_head *list, char *name,
             int config, unsigned long *bits)
{
    struct perf_pmu_format *format;

    format = zalloc(sizeof(*format));
    if (!format)
        return -ENOMEM;

    format->name = strdup(name);
    format->value = config;
    memcpy(format->bits, bits, sizeof(format->bits));

    list_add_tail(&format->list, list);
    return 0;
}

void perf_pmu__set_format(unsigned long *bits, long from, long to)
{
    long b;

    if (!to)
        to = from;

    memset(bits, 0, BITS_TO_BYTES(PERF_PMU_FORMAT_BITS));
    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;
}

struct sevent {
    char *name;
    char *desc;
    char *topic;
    char *str;
    char *pmu;
    char *metric_expr;
    char *metric_name;
};

static int cmp_sevent(const void *a, const void *b)
{
    const struct sevent *as = a;
    const struct sevent *bs = b;

    /* Put extra events last */
    if (!!as->desc != !!bs->desc)
        return !!as->desc - !!bs->desc;
    if (as->topic && bs->topic) {
        int n = strcmp(as->topic, bs->topic);

        if (n)
            return n;
    }
    return strcmp(as->name, bs->name);
}

static void wordwrap(char *s, int start, int max, int corr)
{
    int column = start;
    int n;

    while (*s) {
        int wlen = strcspn(s, " \t");

        if (column + wlen >= max && column > start) {
            printf("\n%*s", start, "");
            column = start + corr;
        }
        n = printf("%s%.*s", column > start ? " " : "", wlen, s);
        if (n <= 0)
            break;
        s += wlen;
        column += n;
        s = ltrim(s);
    }
}

void print_pmu_events(const char *event_glob, bool name_only, bool quiet_flag,
            bool long_desc, bool details_flag)
{
    struct perf_pmu *pmu;
    struct perf_pmu_alias *alias;
    char buf[1024];
    int printed = 0;
    int len, j;
    struct sevent *aliases;
    int numdesc = 0;
    int columns = pager_get_columns();
    char *topic = NULL;

    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(struct sevent) * 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 = alias->desc ? alias->name :
                format_alias(buf, sizeof(buf), pmu, alias);
            bool is_cpu = !strcmp(pmu->name, "cpu");

            if (event_glob != NULL &&
                !(strglobmatch_nocase(name, event_glob) ||
                  (!is_cpu && strglobmatch_nocase(alias->name,
                               event_glob)) ||
                  (alias->topic &&
                   strglobmatch_nocase(alias->topic, event_glob))))
                continue;

            if (is_cpu && !name_only && !alias->desc)
                name = format_alias_or(buf, sizeof(buf), pmu, alias);

            aliases[j].name = name;
            if (is_cpu && !name_only && !alias->desc)
                aliases[j].name = format_alias_or(buf,
                                  sizeof(buf),
                                  pmu, alias);
            aliases[j].name = strdup(aliases[j].name);
            if (!aliases[j].name)
                goto out_enomem;

            aliases[j].desc = long_desc ? alias->long_desc :
                        alias->desc;
            aliases[j].topic = alias->topic;
            aliases[j].str = alias->str;
            aliases[j].pmu = pmu->name;
            aliases[j].metric_expr = alias->metric_expr;
            aliases[j].metric_name = alias->metric_name;
            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].name = s;
            j++;
        }
    }
    len = j;
    qsort(aliases, len, sizeof(struct sevent), cmp_sevent);
    for (j = 0; j < len; j++) {
        /* Skip duplicates */
        if (j > 0 && !strcmp(aliases[j].name, aliases[j - 1].name))
            continue;
        if (name_only) {
            printf("%s ", aliases[j].name);
            continue;
        }
        if (aliases[j].desc && !quiet_flag) {
            if (numdesc++ == 0)
                printf("\n");
            if (aliases[j].topic && (!topic ||
                    strcmp(topic, aliases[j].topic))) {
                printf("%s%s:\n", topic ? "\n" : "",
                        aliases[j].topic);
                topic = aliases[j].topic;
            }
            printf("  %-50s\n", aliases[j].name);
            printf("%*s", 8, "[");
            wordwrap(aliases[j].desc, 8, columns, 0);
            printf("]\n");
            if (details_flag) {
                printf("%*s%s/%s/ ", 8, "", aliases[j].pmu, aliases[j].str);
                if (aliases[j].metric_name)
                    printf(" MetricName: %s", aliases[j].metric_name);
                if (aliases[j].metric_expr)
                    printf(" MetricExpr: %s", aliases[j].metric_expr);
                putchar('\n');
            }
        } else
            printf("  %-50s [Kernel PMU event]\n", aliases[j].name);
        printed++;
    }
    if (printed && pager_in_use())
        printf("\n");
out_free:
    for (j = 0; j < len; j++)
        zfree(&aliases[j].name);
    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;
}