@@ -83,6 +83,7 @@ enum {
TRACECMD_OPTION_HOOK,
TRACECMD_OPTION_OFFSET,
TRACECMD_OPTION_CPUCOUNT,
+ TRACECMD_OPTION_TIME_SHIFT,
};
enum {
@@ -75,6 +75,11 @@ struct input_buffer_instance {
size_t offset;
};
+struct ts_offset_sample {
+ long long time;
+ long long offset;
+};
+
struct tracecmd_input {
struct tep_handle *pevent;
struct tep_plugin_list *plugin_list;
@@ -92,6 +97,8 @@ struct tracecmd_input {
bool use_pipe;
struct cpu_data *cpu_data;
long long ts_offset;
+ int ts_samples_count;
+ struct ts_offset_sample *ts_samples;
double ts2secs;
char * cpustats;
char * uname;
@@ -1044,6 +1051,66 @@ static void free_next(struct tracecmd_input *handle, int cpu)
free_record(record);
}
+static inline unsigned long long
+timestamp_correction_calc(unsigned long long ts, struct ts_offset_sample *min,
+ struct ts_offset_sample *max)
+{
+ long long tscor = min->offset +
+ (((((long long)ts) - min->time)*
+ (max->offset-min->offset))/(max->time-min->time));
+
+ if (tscor < 0)
+ return ts - llabs(tscor);
+
+ return ts + tscor;
+
+}
+
+static unsigned long long timestamp_correct(unsigned long long ts,
+ struct tracecmd_input *handle)
+{
+ int min, mid, max;
+
+ if (handle->ts_offset)
+ return ts + handle->ts_offset;
+ if (!handle->ts_samples_count || !handle->ts_samples)
+ return ts;
+
+ /* We have one sample, nothing to calc here */
+ if (handle->ts_samples_count == 1)
+ return ts + handle->ts_samples[0].offset;
+
+ /* We have two samples, nothing to search here */
+ if (handle->ts_samples_count == 2)
+ return timestamp_correction_calc(ts, &handle->ts_samples[0],
+ &handle->ts_samples[1]);
+
+ /* We have more than two samples */
+ if (ts <= handle->ts_samples[0].time)
+ return timestamp_correction_calc(ts,
+ &handle->ts_samples[0],
+ &handle->ts_samples[1]);
+ else if (ts >= handle->ts_samples[handle->ts_samples_count-1].time)
+ return timestamp_correction_calc(ts,
+ &handle->ts_samples[handle->ts_samples_count-2],
+ &handle->ts_samples[handle->ts_samples_count-1]);
+ min = 0;
+ max = handle->ts_samples_count-1;
+ mid = (min + max)/2;
+ while (min <= max) {
+ if (ts < handle->ts_samples[mid].time)
+ max = mid - 1;
+ else if (ts > handle->ts_samples[mid].time)
+ min = mid + 1;
+ else
+ break;
+ mid = (min + max)/2;
+ }
+
+ return timestamp_correction_calc(ts, &handle->ts_samples[mid],
+ &handle->ts_samples[mid+1]);
+}
+
/*
* Page is mapped, now read in the page header info.
*/
@@ -1065,7 +1132,7 @@ static int update_page_info(struct tracecmd_input *handle, int cpu)
kbuffer_subbuffer_size(kbuf));
return -1;
}
- handle->cpu_data[cpu].timestamp = kbuffer_timestamp(kbuf) + handle->ts_offset;
+ handle->cpu_data[cpu].timestamp = timestamp_correct(kbuffer_timestamp(kbuf), handle);
if (handle->ts2secs)
handle->cpu_data[cpu].timestamp *= handle->ts2secs;
@@ -1792,7 +1859,7 @@ read_again:
goto read_again;
}
- handle->cpu_data[cpu].timestamp = ts + handle->ts_offset;
+ handle->cpu_data[cpu].timestamp = timestamp_correct(ts, handle);
if (handle->ts2secs) {
handle->cpu_data[cpu].timestamp *= handle->ts2secs;
@@ -2117,6 +2184,42 @@ void tracecmd_set_ts2secs(struct tracecmd_input *handle,
handle->use_trace_clock = false;
}
+static int tsync_offset_cmp(const void *a, const void *b)
+{
+ struct ts_offset_sample *ts_a = (struct ts_offset_sample *)a;
+ struct ts_offset_sample *ts_b = (struct ts_offset_sample *)b;
+
+ if (ts_a->time > ts_b->time)
+ return 1;
+ if (ts_a->time < ts_b->time)
+ return -1;
+ return 0;
+}
+
+static void tsync_offset_load(struct tracecmd_input *handle, char *buf)
+{
+ int i, j;
+ long long *buf8 = (long long *)buf;
+
+ for (i = 0; i < handle->ts_samples_count; i++) {
+ handle->ts_samples[i].time = tep_read_number(handle->pevent,
+ buf8+i, 8);
+ handle->ts_samples[i].offset = tep_read_number(handle->pevent,
+ buf8+handle->ts_samples_count+i, 8);
+ }
+ qsort(handle->ts_samples,
+ handle->ts_samples_count, sizeof(struct ts_offset_sample),
+ tsync_offset_cmp);
+ /* Filter possible samples with equal time */
+ for (i = 0, j = 0; i < handle->ts_samples_count; i++) {
+ if (i == 0 ||
+ handle->ts_samples[i].time != handle->ts_samples[i-1].time) {
+ handle->ts_samples[j++] = handle->ts_samples[i];
+ }
+ }
+ handle->ts_samples_count = j;
+}
+
static int handle_options(struct tracecmd_input *handle)
{
long long offset;
@@ -2127,6 +2230,7 @@ static int handle_options(struct tracecmd_input *handle)
struct input_buffer_instance *buffer;
struct hook_list *hook;
char *buf;
+ int sampes_size;
int cpus;
for (;;) {
@@ -2171,6 +2275,25 @@ static int handle_options(struct tracecmd_input *handle)
offset = strtoll(buf, NULL, 0);
handle->ts_offset += offset;
break;
+ case TRACECMD_OPTION_TIME_SHIFT:
+ /*
+ * int (4 bytes) count of timestamp offsets.
+ * long long array of size [count] of times,
+ * when the offsets were calculated.
+ * long long array of size [count] of timestamp offsets.
+ */
+ if (handle->flags & TRACECMD_FL_IGNORE_DATE)
+ break;
+ handle->ts_samples_count = tep_read_number(handle->pevent,
+ buf, 4);
+ sampes_size = (8*handle->ts_samples_count);
+ if (size != (4+(2*sampes_size)))
+ break;
+ handle->ts_samples = malloc(2*sampes_size);
+ if (!handle->ts_samples)
+ return -ENOMEM;
+ tsync_offset_load(handle, buf+4);
+ break;
case TRACECMD_OPTION_CPUSTAT:
buf[size-1] = '\n';
cpustats = realloc(cpustats, cpustats_size + size + 1);
The TRACECMD_OPTION_TIME_SHIFT is used when synchronizing trace time stamps between two trace.dat files. It contains multiple long long (time, offset) pairs, describing time stamps _offset_, measured in the given local _time_. The content of the option buffer is: first 4 bytes - integer, count of timestamp offsets long long array of size _count_, local time in which the offset is measured long long array of size _count_, offset of the time stamps Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com> --- include/trace-cmd/trace-cmd.h | 1 + lib/trace-cmd/trace-input.c | 127 +++++++++++++++++++++++++++++++++- 2 files changed, 126 insertions(+), 2 deletions(-)