diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/perf/util/cgroup.c | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c new file mode 100644 index 000000000..b81324a13 --- /dev/null +++ b/tools/perf/util/cgroup.c @@ -0,0 +1,379 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <subcmd/parse-options.h> +#include "evsel.h" +#include "cgroup.h" +#include "evlist.h" +#include "rblist.h" +#include "metricgroup.h" +#include "stat.h" +#include <linux/zalloc.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <stdlib.h> +#include <string.h> +#include <api/fs/fs.h> + +int nr_cgroups; + +static int open_cgroup(const char *name) +{ + char path[PATH_MAX + 1]; + char mnt[PATH_MAX + 1]; + int fd; + + + if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1, "perf_event")) + return -1; + + scnprintf(path, PATH_MAX, "%s/%s", mnt, name); + + fd = open(path, O_RDONLY); + if (fd == -1) + fprintf(stderr, "no access to cgroup %s\n", path); + + return fd; +} + +static struct cgroup *evlist__find_cgroup(struct evlist *evlist, const char *str) +{ + struct evsel *counter; + /* + * check if cgrp is already defined, if so we reuse it + */ + evlist__for_each_entry(evlist, counter) { + if (!counter->cgrp) + continue; + if (!strcmp(counter->cgrp->name, str)) + return cgroup__get(counter->cgrp); + } + + return NULL; +} + +static struct cgroup *cgroup__new(const char *name, bool do_open) +{ + struct cgroup *cgroup = zalloc(sizeof(*cgroup)); + + if (cgroup != NULL) { + refcount_set(&cgroup->refcnt, 1); + + cgroup->name = strdup(name); + if (!cgroup->name) + goto out_err; + + if (do_open) { + cgroup->fd = open_cgroup(name); + if (cgroup->fd == -1) + goto out_free_name; + } else { + cgroup->fd = -1; + } + } + + return cgroup; + +out_free_name: + zfree(&cgroup->name); +out_err: + free(cgroup); + return NULL; +} + +struct cgroup *evlist__findnew_cgroup(struct evlist *evlist, const char *name) +{ + struct cgroup *cgroup = evlist__find_cgroup(evlist, name); + + return cgroup ?: cgroup__new(name, true); +} + +static int add_cgroup(struct evlist *evlist, const char *str) +{ + struct evsel *counter; + struct cgroup *cgrp = evlist__findnew_cgroup(evlist, str); + int n; + + if (!cgrp) + return -1; + /* + * find corresponding event + * if add cgroup N, then need to find event N + */ + n = 0; + evlist__for_each_entry(evlist, counter) { + if (n == nr_cgroups) + goto found; + n++; + } + + cgroup__put(cgrp); + return -1; +found: + counter->cgrp = cgrp; + return 0; +} + +static void cgroup__delete(struct cgroup *cgroup) +{ + if (cgroup->fd >= 0) + close(cgroup->fd); + zfree(&cgroup->name); + free(cgroup); +} + +void cgroup__put(struct cgroup *cgrp) +{ + if (cgrp && refcount_dec_and_test(&cgrp->refcnt)) { + cgroup__delete(cgrp); + } +} + +struct cgroup *cgroup__get(struct cgroup *cgroup) +{ + if (cgroup) + refcount_inc(&cgroup->refcnt); + return cgroup; +} + +static void evsel__set_default_cgroup(struct evsel *evsel, struct cgroup *cgroup) +{ + if (evsel->cgrp == NULL) + evsel->cgrp = cgroup__get(cgroup); +} + +void evlist__set_default_cgroup(struct evlist *evlist, struct cgroup *cgroup) +{ + struct evsel *evsel; + + evlist__for_each_entry(evlist, evsel) + evsel__set_default_cgroup(evsel, cgroup); +} + +int parse_cgroups(const struct option *opt, const char *str, + int unset __maybe_unused) +{ + struct evlist *evlist = *(struct evlist **)opt->value; + struct evsel *counter; + struct cgroup *cgrp = NULL; + const char *p, *e, *eos = str + strlen(str); + char *s; + int ret, i; + + if (list_empty(&evlist->core.entries)) { + fprintf(stderr, "must define events before cgroups\n"); + return -1; + } + + for (;;) { + p = strchr(str, ','); + e = p ? p : eos; + + /* allow empty cgroups, i.e., skip */ + if (e - str) { + /* termination added */ + s = strndup(str, e - str); + if (!s) + return -1; + ret = add_cgroup(evlist, s); + free(s); + if (ret) + return -1; + } + /* nr_cgroups is increased een for empty cgroups */ + nr_cgroups++; + if (!p) + break; + str = p+1; + } + /* for the case one cgroup combine to multiple events */ + i = 0; + if (nr_cgroups == 1) { + evlist__for_each_entry(evlist, counter) { + if (i == 0) + cgrp = counter->cgrp; + else { + counter->cgrp = cgrp; + refcount_inc(&cgrp->refcnt); + } + i++; + } + } + return 0; +} + +int evlist__expand_cgroup(struct evlist *evlist, const char *str, + struct rblist *metric_events, bool open_cgroup) +{ + struct evlist *orig_list, *tmp_list; + struct evsel *pos, *evsel, *leader; + struct rblist orig_metric_events; + struct cgroup *cgrp = NULL; + const char *p, *e, *eos = str + strlen(str); + int ret = -1; + + if (evlist->core.nr_entries == 0) { + fprintf(stderr, "must define events before cgroups\n"); + return -EINVAL; + } + + orig_list = evlist__new(); + tmp_list = evlist__new(); + if (orig_list == NULL || tmp_list == NULL) { + fprintf(stderr, "memory allocation failed\n"); + return -ENOMEM; + } + + /* save original events and init evlist */ + perf_evlist__splice_list_tail(orig_list, &evlist->core.entries); + evlist->core.nr_entries = 0; + + if (metric_events) { + orig_metric_events = *metric_events; + rblist__init(metric_events); + } else { + rblist__init(&orig_metric_events); + } + + for (;;) { + p = strchr(str, ','); + e = p ? p : eos; + + /* allow empty cgroups, i.e., skip */ + if (e - str) { + /* termination added */ + char *name = strndup(str, e - str); + if (!name) + goto out_err; + + cgrp = cgroup__new(name, open_cgroup); + free(name); + if (cgrp == NULL) + goto out_err; + } else { + cgrp = NULL; + } + + leader = NULL; + evlist__for_each_entry(orig_list, pos) { + evsel = evsel__clone(pos); + if (evsel == NULL) + goto out_err; + + cgroup__put(evsel->cgrp); + evsel->cgrp = cgroup__get(cgrp); + + if (evsel__is_group_leader(pos)) + leader = evsel; + evsel->leader = leader; + + evlist__add(tmp_list, evsel); + } + /* cgroup__new() has a refcount, release it here */ + cgroup__put(cgrp); + nr_cgroups++; + + if (metric_events) { + perf_stat__collect_metric_expr(tmp_list); + if (metricgroup__copy_metric_events(tmp_list, cgrp, + metric_events, + &orig_metric_events) < 0) + break; + } + + perf_evlist__splice_list_tail(evlist, &tmp_list->core.entries); + tmp_list->core.nr_entries = 0; + + if (!p) { + ret = 0; + break; + } + str = p+1; + } + +out_err: + evlist__delete(orig_list); + evlist__delete(tmp_list); + rblist__exit(&orig_metric_events); + + return ret; +} + +static struct cgroup *__cgroup__findnew(struct rb_root *root, uint64_t id, + bool create, const char *path) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent = NULL; + struct cgroup *cgrp; + + while (*p != NULL) { + parent = *p; + cgrp = rb_entry(parent, struct cgroup, node); + + if (cgrp->id == id) + return cgrp; + + if (cgrp->id < id) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + if (!create) + return NULL; + + cgrp = malloc(sizeof(*cgrp)); + if (cgrp == NULL) + return NULL; + + cgrp->name = strdup(path); + if (cgrp->name == NULL) { + free(cgrp); + return NULL; + } + + cgrp->fd = -1; + cgrp->id = id; + refcount_set(&cgrp->refcnt, 1); + + rb_link_node(&cgrp->node, parent, p); + rb_insert_color(&cgrp->node, root); + + return cgrp; +} + +struct cgroup *cgroup__findnew(struct perf_env *env, uint64_t id, + const char *path) +{ + struct cgroup *cgrp; + + down_write(&env->cgroups.lock); + cgrp = __cgroup__findnew(&env->cgroups.tree, id, true, path); + up_write(&env->cgroups.lock); + return cgrp; +} + +struct cgroup *cgroup__find(struct perf_env *env, uint64_t id) +{ + struct cgroup *cgrp; + + down_read(&env->cgroups.lock); + cgrp = __cgroup__findnew(&env->cgroups.tree, id, false, NULL); + up_read(&env->cgroups.lock); + return cgrp; +} + +void perf_env__purge_cgroups(struct perf_env *env) +{ + struct rb_node *node; + struct cgroup *cgrp; + + down_write(&env->cgroups.lock); + while (!RB_EMPTY_ROOT(&env->cgroups.tree)) { + node = rb_first(&env->cgroups.tree); + cgrp = rb_entry(node, struct cgroup, node); + + rb_erase(node, &env->cgroups.tree); + cgroup__put(cgrp); + } + up_write(&env->cgroups.lock); +} |