@@ -213,6 +213,7 @@ struct buffer_instance {
char *name;
struct tracefs_instance *tracefs;
unsigned long long trace_id;
+ unsigned long long first_ts;
char *cpumask;
char *output_file;
struct event_list *events;
@@ -40,6 +40,7 @@
#ifdef VSOCK
#include <linux/vm_sockets.h>
#endif
+#include <traceevent/kbuffer.h>
#include "tracefs.h"
#include "version.h"
@@ -685,34 +686,6 @@ add_tsc2nsec(struct tracecmd_output *handle, struct tsc_nsec *tsc2nsec)
tracecmd_add_option_v(handle, TRACECMD_OPTION_TSC2NSEC, vector, 3);
}
-static void host_tsync_complete(struct common_record_context *ctx,
- struct buffer_instance *instance)
-{
- struct tracecmd_output *handle = NULL;
- int fd = -1;
- int ret;
-
- ret = tracecmd_tsync_with_guest_stop(instance->tsync);
- if (!ret) {
- fd = open(instance->output_file, O_RDWR);
- if (fd < 0)
- die("error opening %s", instance->output_file);
- handle = tracecmd_get_output_handle_fd(fd);
- if (!handle)
- die("cannot create output handle");
-
- if (ctx->tsc2nsec.mult)
- add_tsc2nsec(handle, &ctx->tsc2nsec);
-
- tracecmd_write_guest_time_shift(handle, instance->tsync);
- tracecmd_append_options(handle);
- tracecmd_output_close(handle);
- }
-
- tracecmd_tsync_free(instance->tsync);
- instance->tsync = NULL;
-}
-
static void tell_guests_to_stop(struct common_record_context *ctx)
{
struct buffer_instance *instance;
@@ -725,7 +698,7 @@ static void tell_guests_to_stop(struct common_record_context *ctx)
for_all_instances(instance) {
if (is_guest(instance))
- host_tsync_complete(ctx, instance);
+ tracecmd_tsync_with_guest_stop(instance->tsync);
}
/* Wait for guests to acknowledge */
@@ -4183,7 +4156,105 @@ static void add_options(struct tracecmd_output *handle, struct common_record_con
free(clocks);
}
-static void write_guest_file(struct buffer_instance *instance)
+int get_first_ts(struct kbuffer *kbuf, char *page, int psize, const char *file, unsigned long long *ts)
+{
+ int rsize;
+ int ret = -1;
+ char *data;
+ int fd;
+
+ fd = open(file, O_RDONLY);
+ if (fd < 0)
+ return -1;
+
+ rsize = read(fd, page, psize);
+ if (rsize <= 0)
+ goto error;
+
+ kbuffer_load_subbuffer(kbuf, page);
+ if (kbuffer_subbuffer_size(kbuf) > rsize)
+ goto error;
+
+ data = kbuffer_read_event(kbuf, ts);
+ if (!data)
+ goto error;
+
+ ret = 0;
+error:
+ close(fd);
+ return ret;
+}
+
+int get_first_ts_instance(struct buffer_instance *instance)
+{
+ struct tracecmd_ts_corrections corrections;
+ unsigned long long first_ts = 0;
+ enum kbuffer_long_size long_size;
+ enum kbuffer_endian endian;
+ struct kbuffer *kbuf = NULL;
+ unsigned long long ts;
+ unsigned int flags;
+ int first_ts_cpu;
+ bool first = true;
+ char *page;
+ char *file;
+ int psize;
+ int ret;
+ int i;
+
+ psize = getpagesize();
+ page = calloc(1, psize);
+ if (!page)
+ return -1;
+
+ if (tracecmd_host_bigendian())
+ endian = KBUFFER_ENDIAN_BIG;
+ else
+ endian = KBUFFER_ENDIAN_LITTLE;
+ if (sizeof(long) == 8)
+ long_size = KBUFFER_LSIZE_8;
+ else
+ long_size = KBUFFER_LSIZE_4;
+
+ kbuf = kbuffer_alloc(long_size, endian);
+ if (!kbuf)
+ goto out;
+
+ for (i = 0; i < instance->cpu_count; i++) {
+ file = get_temp_file(instance, i);
+ if (!file)
+ continue;
+ if (!get_first_ts(kbuf, page, psize, file, &ts)) {
+ if (first || ts < first_ts) {
+ first_ts = ts;
+ first_ts_cpu = i;
+ first = false;
+ }
+ }
+ put_temp_file(file);
+ }
+ if (!first) {
+ if (is_guest(instance)) {
+ ret = tracecmd_tsync_get_proto_flags(instance->tsync, &flags);
+ if (ret)
+ goto out;
+ ret = tracecmd_tsync_get_offsets(instance->tsync, first_ts_cpu, &corrections);
+ if (ret)
+ goto out;
+ instance->first_ts = tracecmd_guest_ts_calc(first_ts, &corrections, flags);
+ free(corrections.ts_samples);
+ } else {
+ instance->first_ts = first_ts;
+ }
+ }
+
+out:
+ kbuffer_free(kbuf);
+ free(page);
+ return first ? -1 : 0;
+}
+
+static void write_guest_file(struct common_record_context *ctx, struct buffer_instance *instance)
{
struct tracecmd_output *handle;
int cpu_count = instance->cpu_count;
@@ -4201,6 +4272,12 @@ static void write_guest_file(struct buffer_instance *instance)
die("error writing to %s", file);
if (instance->flags & BUFFER_FL_TSC2NSEC)
tracecmd_set_out_clock(handle, TSCNSEC_CLOCK);
+
+ if (ctx->tsc2nsec.mult)
+ add_tsc2nsec(handle, &ctx->tsc2nsec);
+ tracecmd_write_guest_time_shift(handle, instance->tsync);
+ tracecmd_append_options(handle);
+
temp_files = malloc(sizeof(*temp_files) * cpu_count);
if (!temp_files)
die("failed to allocate temp_files for %d cpus",
@@ -4219,6 +4296,9 @@ static void write_guest_file(struct buffer_instance *instance)
for (i = 0; i < cpu_count; i++)
put_temp_file(temp_files[i]);
free(temp_files);
+
+ tracecmd_tsync_free(instance->tsync);
+ instance->tsync = NULL;
}
static void record_data(struct common_record_context *ctx)
@@ -4229,11 +4309,21 @@ static void record_data(struct common_record_context *ctx)
bool local = false;
int max_cpu_count = local_cpu_count;
char **temp_files;
+ int ret;
int i;
+ if (ctx->tsc2nsec.mult) {
+ for_all_instances(instance) {
+ ret = get_first_ts_instance(instance);
+ if (!ret &&
+ (!ctx->tsc2nsec.offset || ctx->tsc2nsec.offset > instance->first_ts))
+ ctx->tsc2nsec.offset = instance->first_ts;
+ }
+ }
+
for_all_instances(instance) {
if (is_guest(instance))
- write_guest_file(instance);
+ write_guest_file(ctx, instance);
else if (host && instance->msg_handle)
finish_network(instance->msg_handle);
else
When converting TSC timestamps to nanoseconds, an offset is used. That offset is subtracted from each TSC timestamp, before the conversion. At the end of the trace, the lowest recorded TSC timestamp is selected as TSC offset, that will be used for tsc2nsec conversion. Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> --- tracecmd/include/trace-local.h | 1 + tracecmd/trace-record.c | 152 ++++++++++++++++++++++++++------- 2 files changed, 122 insertions(+), 31 deletions(-)