+ return 1000000000ULL;
+}
+
+static
+int trace_clock_uuid_monotonic(char *uuid)
+{
+ int ret = 0;
+ size_t len;
+ FILE *fp;
+
+ /*
+ * boot_id needs to be read once before being used concurrently
+ * to deal with a Linux kernel race. A fix is proposed for
+ * upstream, but the work-around is needed for older kernels.
+ */
+ fp = fopen("/proc/sys/kernel/random/boot_id", "r");
+ if (!fp) {
+ return -ENOENT;
+ }
+ len = fread(uuid, 1, LTTNG_UST_UUID_STR_LEN - 1, fp);
+ if (len < LTTNG_UST_UUID_STR_LEN - 1) {
+ ret = -EINVAL;
+ goto end;
+ }
+ uuid[LTTNG_UST_UUID_STR_LEN - 1] = '\0';
+end:
+ fclose(fp);
+ return ret;
+}
+
+static
+const char *trace_clock_name_monotonic(void)
+{
+ return "monotonic";
+}
+
+static
+const char *trace_clock_description_monotonic(void)
+{
+ return "Monotonic Clock";
+}
+
+int lttng_ust_trace_clock_set_read64_cb(lttng_ust_clock_read64_function read64_cb)
+{
+ if (CMM_LOAD_SHARED(lttng_ust_trace_clock))