#include <asm/local.h>
+/*
+ * The "absolute" timestamp in the buffer is only 59 bits.
+ * If a clock has the 5 MSBs set, it needs to be saved and
+ * reinserted.
+ */
+#define TS_MSB (0xf8ULL << 56)
+#define ABS_TS_MASK (~TS_MSB)
+
static void update_pages_handler(struct work_struct *work);
/*
}
#endif
+/*
+ * The absolute time stamp drops the 5 MSBs and some clocks may
+ * require them. The rb_fix_abs_ts() will take a previous full
+ * time stamp, and add the 5 MSB of that time stamp on to the
+ * saved absolute time stamp. Then they are compared in case of
+ * the unlikely event that the latest time stamp incremented
+ * the 5 MSB.
+ */
+static inline u64 rb_fix_abs_ts(u64 abs, u64 save_ts)
+{
+ if (save_ts & TS_MSB) {
+ abs |= save_ts & TS_MSB;
+ /* Check for overflow */
+ if (unlikely(abs < save_ts))
+ abs += 1ULL << 59;
+ }
+ return abs;
+}
static inline u64 rb_time_stamp(struct trace_buffer *buffer);
u64 ts;
/* If the event includes an absolute time, then just use that */
- if (event->type_len == RINGBUF_TYPE_TIME_STAMP)
- return rb_event_time_stamp(event);
+ if (event->type_len == RINGBUF_TYPE_TIME_STAMP) {
+ ts = rb_event_time_stamp(event);
+ return rb_fix_abs_ts(ts, cpu_buffer->tail_page->page->time_stamp);
+ }
nest = local_read(&cpu_buffer->committing);
verify_event(cpu_buffer, event);
(RB_ADD_STAMP_FORCE | RB_ADD_STAMP_ABSOLUTE);
if (unlikely(info->delta > (1ULL << 59))) {
+ /*
+ * Some timers can use more than 59 bits, and when a timestamp
+ * is added to the buffer, it will lose those bits.
+ */
+ if (abs && (info->ts & TS_MSB)) {
+ info->delta &= ABS_TS_MASK;
+
/* did the clock go backwards */
- if (info->before == info->after && info->before > info->ts) {
+ } else if (info->before == info->after && info->before > info->ts) {
/* not interrupted */
static int once;
case RINGBUF_TYPE_TIME_STAMP:
delta = rb_event_time_stamp(event);
- ts = delta;
+ ts = rb_fix_abs_ts(delta, ts);
pr_warn(" [%lld] absolute:%lld TIME STAMP\n", ts, delta);
break;
case RINGBUF_TYPE_TIME_STAMP:
delta = rb_event_time_stamp(event);
- ts = delta;
+ ts = rb_fix_abs_ts(delta, ts);
break;
case RINGBUF_TYPE_PADDING:
case RINGBUF_TYPE_TIME_STAMP:
delta = rb_event_time_stamp(event);
+ delta = rb_fix_abs_ts(delta, cpu_buffer->read_stamp);
cpu_buffer->read_stamp = delta;
return;
case RINGBUF_TYPE_TIME_STAMP:
delta = rb_event_time_stamp(event);
+ delta = rb_fix_abs_ts(delta, iter->read_stamp);
iter->read_stamp = delta;
return;
case RINGBUF_TYPE_TIME_STAMP:
if (ts) {
*ts = rb_event_time_stamp(event);
+ *ts = rb_fix_abs_ts(*ts, reader->page->time_stamp);
ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
cpu_buffer->cpu, ts);
}
case RINGBUF_TYPE_TIME_STAMP:
if (ts) {
*ts = rb_event_time_stamp(event);
+ *ts = rb_fix_abs_ts(*ts, iter->head_page->page->time_stamp);
ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
cpu_buffer->cpu, ts);
}