zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/tools/perf/util/cgroup.c b/ap/os/linux/linux-3.4.x/tools/perf/util/cgroup.c
new file mode 100644
index 0000000..dbe2f16
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/tools/perf/util/cgroup.c
@@ -0,0 +1,177 @@
+#include "util.h"
+#include "../perf.h"
+#include "parse-options.h"
+#include "evsel.h"
+#include "cgroup.h"
+#include "evlist.h"
+
+int nr_cgroups;
+
+static int
+cgroupfs_find_mountpoint(char *buf, size_t maxlen)
+{
+ FILE *fp;
+ char mountpoint[PATH_MAX + 1], tokens[PATH_MAX + 1], type[PATH_MAX + 1];
+ char *token, *saved_ptr = NULL;
+ int found = 0;
+
+ fp = fopen("/proc/mounts", "r");
+ if (!fp)
+ return -1;
+
+ /*
+ * in order to handle split hierarchy, we need to scan /proc/mounts
+ * and inspect every cgroupfs mount point to find one that has
+ * perf_event subsystem
+ */
+ while (fscanf(fp, "%*s %"STR(PATH_MAX)"s %"STR(PATH_MAX)"s %"
+ STR(PATH_MAX)"s %*d %*d\n",
+ mountpoint, type, tokens) == 3) {
+
+ if (!strcmp(type, "cgroup")) {
+
+ token = strtok_r(tokens, ",", &saved_ptr);
+
+ while (token != NULL) {
+ if (!strcmp(token, "perf_event")) {
+ found = 1;
+ break;
+ }
+ token = strtok_r(NULL, ",", &saved_ptr);
+ }
+ }
+ if (found)
+ break;
+ }
+ fclose(fp);
+ if (!found)
+ return -1;
+
+ if (strlen(mountpoint) < maxlen) {
+ strcpy(buf, mountpoint);
+ return 0;
+ }
+ return -1;
+}
+
+static int open_cgroup(char *name)
+{
+ char path[PATH_MAX + 1];
+ char mnt[PATH_MAX + 1];
+ int fd;
+
+
+ if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1))
+ return -1;
+
+ snprintf(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 int add_cgroup(struct perf_evlist *evlist, char *str)
+{
+ struct perf_evsel *counter;
+ struct cgroup_sel *cgrp = NULL;
+ int n;
+ /*
+ * check if cgrp is already defined, if so we reuse it
+ */
+ list_for_each_entry(counter, &evlist->entries, node) {
+ cgrp = counter->cgrp;
+ if (!cgrp)
+ continue;
+ if (!strcmp(cgrp->name, str))
+ break;
+
+ cgrp = NULL;
+ }
+
+ if (!cgrp) {
+ cgrp = zalloc(sizeof(*cgrp));
+ if (!cgrp)
+ return -1;
+
+ cgrp->name = str;
+
+ cgrp->fd = open_cgroup(str);
+ if (cgrp->fd == -1) {
+ free(cgrp);
+ return -1;
+ }
+ }
+
+ /*
+ * find corresponding event
+ * if add cgroup N, then need to find event N
+ */
+ n = 0;
+ list_for_each_entry(counter, &evlist->entries, node) {
+ if (n == nr_cgroups)
+ goto found;
+ n++;
+ }
+ if (cgrp->refcnt == 0)
+ free(cgrp);
+
+ return -1;
+found:
+ cgrp->refcnt++;
+ counter->cgrp = cgrp;
+ return 0;
+}
+
+void close_cgroup(struct cgroup_sel *cgrp)
+{
+ if (!cgrp)
+ return;
+
+ /* XXX: not reentrant */
+ if (--cgrp->refcnt == 0) {
+ close(cgrp->fd);
+ free(cgrp->name);
+ free(cgrp);
+ }
+}
+
+int parse_cgroups(const struct option *opt __used, const char *str,
+ int unset __used)
+{
+ struct perf_evlist *evlist = *(struct perf_evlist **)opt->value;
+ const char *p, *e, *eos = str + strlen(str);
+ char *s;
+ int ret;
+
+ if (list_empty(&evlist->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);
+ if (ret) {
+ free(s);
+ return -1;
+ }
+ }
+ /* nr_cgroups is increased een for empty cgroups */
+ nr_cgroups++;
+ if (!p)
+ break;
+ str = p+1;
+ }
+ return 0;
+}