Trace clock, used for curent trace sessions is saved in the trace.dat
file. This information is used when displaying timestamps of the events.
However, only the selected clock is needed.
A new API is added:
tracecmd_set_out_clock();
that can be used to set the trace clock on the output handle.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@xxxxxxxxx>
---
.../include/private/trace-cmd-private.h | 1 +
lib/trace-cmd/trace-output.c | 66 +++++++++++++++----
2 files changed, 56 insertions(+), 11 deletions(-)
diff --git a/lib/trace-cmd/include/private/trace-cmd-private.h b/lib/trace-cmd/include/private/trace-cmd-private.h
index 27f4c9c3..a4637046 100644
--- a/lib/trace-cmd/include/private/trace-cmd-private.h
+++ b/lib/trace-cmd/include/private/trace-cmd-private.h
@@ -83,6 +83,7 @@ tracecmd_plugin_context_output(struct trace_plugin_context *trace_context);
void tracecmd_set_quiet(struct tracecmd_output *handle, bool set_quiet);
bool tracecmd_get_quiet(struct tracecmd_output *handle);
+void tracecmd_set_out_clock(struct tracecmd_output *handle, char *clock);
static inline int tracecmd_host_bigendian(void)
{
diff --git a/lib/trace-cmd/trace-output.c b/lib/trace-cmd/trace-output.c
index 54ddcb54..ea6d1ba3 100644
--- a/lib/trace-cmd/trace-output.c
+++ b/lib/trace-cmd/trace-output.c
@@ -59,6 +59,7 @@ struct tracecmd_output {
unsigned long file_state;
struct list_head options;
struct tracecmd_msg_handle *msg_handle;
+ char *trace_clock;
};
struct list_event {
@@ -118,6 +119,12 @@ void tracecmd_set_quiet(struct tracecmd_output *handle, bool set_quiet)
handle->quiet = set_quiet;
}
+void tracecmd_set_out_clock(struct tracecmd_output *handle, char *clock)
+{
+ if (handle && clock)
+ handle->trace_clock = strdup(clock);
+}
+
/**
* tracecmd_get_quiet - Get if to print output to the screen
* Returns non zero, if no output to the screen should be printed
@@ -150,7 +157,7 @@ void tracecmd_output_free(struct tracecmd_output *handle)
free(option->data);
free(option);
}
-
+ free(handle->trace_clock);
free(handle);
}
@@ -1359,6 +1366,46 @@ out_free:
return NULL;
}
+static int save_clock(struct tracecmd_output *handle, char *clock)
+{
+ unsigned long long endian8;
+ char *str = NULL;
+ int ret;
+
+ ret = asprintf(&str, "[%s]", clock);
+ if (ret < 0)
+ return -1;
+
+ endian8 = convert_endian_8(handle, strlen(str));
+ ret = do_write_check(handle, &endian8, 8);
+ if (ret)
+ goto out;
+ ret = do_write_check(handle, str, strlen(str));
+
+out:
+ free(str);
+ return ret;
+}
+
+static char *get_clock(struct tracecmd_output *handle)
+{
+ struct tracefs_instance *inst;
+
+ if (handle->trace_clock)
+ return handle->trace_clock;
+
+ /*
+ * If no clock is set on this handle, get the trace clock of
+ * the top instance in the handle's tracing dir
+ */
+ inst = tracefs_instance_alloc(handle->tracing_dir, NULL);
+ if (!inst)
+ return NULL;
+ handle->trace_clock = tracefs_get_clock(inst);
+ tracefs_instance_free(inst);
+ return handle->trace_clock;
+}
+
int tracecmd_write_cpu_data(struct tracecmd_output *handle,
int cpus, char * const *cpu_data_files)
{
@@ -1366,6 +1413,7 @@ int tracecmd_write_cpu_data(struct tracecmd_output *handle,
unsigned long long *sizes = NULL;
off64_t offset;
unsigned long long endian8;
+ char *clock = NULL;
off64_t check_size;
char *file;
struct stat st;
@@ -1403,18 +1451,14 @@ int tracecmd_write_cpu_data(struct tracecmd_output *handle,
* we need to find the size of it before we define the final
* offsets.
*/
- file = get_tracing_file(handle, "trace_clock");
- if (!file)
+ clock = get_clock(handle);
+ if (!clock)
goto out_free;
-
/* Save room for storing the size */
offset += 8;
-
- ret = stat(file, &st);
- if (ret >= 0)
- offset += get_size(file);
-
- put_tracing_file(file);
+ offset += strlen(clock);
+ /* 2 bytes for [] around the clock */
+ offset += 2;
/* Page align offset */
offset = (offset + (handle->page_size - 1)) & ~(handle->page_size - 1);
@@ -1439,7 +1483,7 @@ int tracecmd_write_cpu_data(struct tracecmd_output *handle,
goto out_free;
}
- if (save_tracing_file_data(handle, "trace_clock") < 0)
+ if (save_clock(handle, clock))
goto out_free;
for (i = 0; i < cpus; i++) {
--
2.30.2
|