/*
- * Copyright (C) 2010 Pierre-Marc Fournier
- * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * SPDX-License-Identifier: LGPL-2.1-only
*
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; version 2.1 of
- * the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ * Copyright (C) 2010 Pierre-Marc Fournier
+ * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*/
#ifndef _UST_CLOCK_H
#include <sys/time.h>
#include <stdint.h>
#include <stddef.h>
+#include <stdio.h>
+#include <urcu/system.h>
+#include <urcu/arch.h>
+#include <lttng/ust-clock.h>
-/* TRACE CLOCK */
+#include "lttng-ust-uuid.h"
-/*
- * Currently using the kernel MONOTONIC clock, waiting for kernel-side
- * LTTng to implement mmap'd trace clock.
- */
+struct lttng_trace_clock {
+ uint64_t (*read64)(void);
+ uint64_t (*freq)(void);
+ int (*uuid)(char *uuid);
+ const char *(*name)(void);
+ const char *(*description)(void);
+};
+
+extern struct lttng_trace_clock *lttng_trace_clock;
+
+void lttng_ust_clock_init(void);
-/* Choosing correct trace clock */
+/* Use the kernel MONOTONIC clock. */
-static __inline__ uint64_t trace_clock_read64(void)
+static __inline__
+uint64_t trace_clock_read64_monotonic(void)
{
struct timespec ts;
- clock_gettime(CLOCK_MONOTONIC, &ts);
- return (ts.tv_sec * 1000000000) + ts.tv_nsec;
+ if (caa_unlikely(clock_gettime(CLOCK_MONOTONIC, &ts))) {
+ ts.tv_sec = 0;
+ ts.tv_nsec = 0;
+ }
+ return ((uint64_t) ts.tv_sec * 1000000000ULL) + ts.tv_nsec;
}
-static __inline__ uint32_t trace_clock_freq_scale(void)
+static __inline__
+uint64_t trace_clock_read64(void)
{
- return 1;
+ struct lttng_trace_clock *ltc = CMM_LOAD_SHARED(lttng_trace_clock);
+
+ if (caa_likely(!ltc)) {
+ return trace_clock_read64_monotonic();
+ } else {
+ cmm_read_barrier_depends(); /* load ltc before content */
+ return ltc->read64();
+ }
}
#endif /* _UST_CLOCK_H */