@@ -19,6 +19,7 @@ OBJS += trace-msg.o
OBJS += trace-plugin.o
ifeq ($(VSOCK_DEFINED), 1)
OBJS += trace-timesync.o
+OBJS += trace-timesync-ptp.o
endif
# Additional util objects
new file mode 100644
@@ -0,0 +1,714 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Copyright (C) 2019, VMware, Tzvetomir Stoyanov tz.stoyanov@gmail.com>
+ *
+ */
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <linux/vm_sockets.h>
+#include <sys/types.h>
+#include <linux/types.h>
+#include <time.h>
+#include <sched.h>
+#include <limits.h>
+
+#include "trace-cmd.h"
+#include "tracefs.h"
+#include "trace-tsync-local.h"
+#include "trace-msg.h"
+#include "trace-cmd-local.h"
+
+typedef __be32 be32;
+typedef __u64 u64;
+typedef __s64 s64;
+
+#define PTP_SYNC_LOOP 339
+
+#define PTP_SYNC_PKT_START 1
+#define PTP_SYNC_PKT_PROBE 2
+#define PTP_SYNC_PKT_PROBES 3
+#define PTP_SYNC_PKT_OFFSET 4
+#define PTP_SYNC_PKT_END 5
+
+/* print time sync debug messages */
+#define TSYNC_DEBUG
+
+struct ptp_clock_sync {
+ struct tep_handle *tep;
+ struct tep_format_field *id;
+ int raw_id;
+ int marker_fd;
+ int series_id;
+ int flags;
+ int debug_fd;
+};
+
+enum {
+/*
+ * Consider only the probe with fastest response time,
+ * otherwise make a histogram from all probes.
+ */
+ PTP_FLAG_FASTEST_RESPONSE = (1 << 0),
+/*
+ * Use trace marker to get the clock,
+ * otherwise use the system clock directly.
+ */
+ PTP_FLAG_USE_MARKER = (1 << 1),
+};
+static int ptp_flags = PTP_FLAG_FASTEST_RESPONSE | PTP_FLAG_USE_MARKER;
+
+/*
+ * Calculated using formula [CPU rate]*[calculated offset deviation]
+ * tested on 3GHz CPU, with x86-tsc trace clock and compare the calculated
+ * offset with /sys/kernel/debug/kvm/<VM ID>/vcpu0/tsc-offset
+ * measured 2000ns deviation
+ * using PTP flags PTP_FLAG_FASTEST_RESPONSE | PTP_FLAG_USE_MARKER
+ */
+#define PTP_ACCURACY 6000
+#define PTP_NAME "ptp"
+
+struct ptp_clock_start_msg {
+ be32 series_id;
+ be32 flags;
+} __packed;
+
+struct ptp_clock_sample {
+ s64 ts;
+ be32 id;
+} __packed;
+
+struct ptp_clock_result_msg {
+ be32 series_id;
+ be32 count;
+ struct ptp_clock_sample samples[2*PTP_SYNC_LOOP];
+} __packed;
+
+struct ptp_clock_offset_msg {
+ s64 ts;
+ s64 offset;
+};
+
+struct ptp_markers_context {
+ struct clock_sync_context *clock;
+ struct ptp_clock_sync *ptp;
+ struct ptp_clock_result_msg msg;
+ int size;
+};
+
+struct ptp_marker_buf {
+ int local_cid;
+ int remote_cid;
+ int count;
+ int packet_id;
+} __packed;
+
+struct ptp_marker {
+ int series_id;
+ struct ptp_marker_buf data;
+} __packed;
+
+static int ptp_clock_sync_init(struct tracecmd_time_sync *tsync)
+{
+ const char *systems[] = {"ftrace", NULL};
+ struct clock_sync_context *clock_context;
+ struct ptp_clock_sync *ptp;
+ struct tep_event *raw;
+ char *path;
+
+ if (!tsync || !tsync->context)
+ return -1;
+ clock_context = (struct clock_sync_context *)tsync->context;
+ if (clock_context->proto_data)
+ return 0;
+
+ ptp = calloc(1, sizeof(struct ptp_clock_sync));
+ if (!ptp)
+ return -1;
+
+ ptp->marker_fd = -1;
+ ptp->debug_fd = -1;
+
+ path = tracefs_instance_get_dir(clock_context->instance);
+ if (!path)
+ goto error;
+ ptp->tep = tracefs_local_events_system(path, systems);
+ tracefs_put_tracing_file(path);
+ if (!ptp->tep)
+ goto error;
+ raw = tep_find_event_by_name(ptp->tep, "ftrace", "raw_data");
+ if (!raw)
+ goto error;
+ ptp->id = tep_find_field(raw, "id");
+ if (!ptp->id)
+ goto error;
+ ptp->raw_id = raw->id;
+
+ tep_set_file_bigendian(ptp->tep, tracecmd_host_bigendian());
+ tep_set_local_bigendian(ptp->tep, tracecmd_host_bigendian());
+
+ path = tracefs_instance_get_file(clock_context->instance, "trace_marker_raw");
+ if (!path)
+ goto error;
+ ptp->marker_fd = open(path, O_WRONLY);
+ tracefs_put_tracing_file(path);
+
+ clock_context->proto_data = ptp;
+
+#ifdef TSYNC_DEBUG
+ if (clock_context->is_server) {
+ char buff[256];
+ int res_fd;
+
+ sprintf(buff, "res-cid%d.txt", clock_context->remote_cid);
+
+ res_fd = open(buff, O_CREAT|O_WRONLY|O_TRUNC, 0644);
+ if (res_fd > 0)
+ close(res_fd);
+ }
+#endif
+
+ return 0;
+
+error:
+ if (ptp) {
+ tep_free(ptp->tep);
+ if (ptp->marker_fd >= 0)
+ close(ptp->marker_fd);
+ }
+ free(ptp);
+ return -1;
+}
+
+static int ptp_clock_sync_free(struct tracecmd_time_sync *tsync)
+{
+ struct clock_sync_context *clock_context;
+ struct ptp_clock_sync *ptp;
+
+ if (!tsync || !tsync->context)
+ return -1;
+ clock_context = (struct clock_sync_context *)tsync->context;
+
+ if (clock_context && clock_context->proto_data) {
+ ptp = (struct ptp_clock_sync *)clock_context->proto_data;
+ tep_free(ptp->tep);
+ if (ptp->marker_fd >= 0)
+ close(ptp->marker_fd);
+ if (ptp->debug_fd >= 0)
+ close(ptp->debug_fd);
+ free(clock_context->proto_data);
+ clock_context->proto_data = NULL;
+ }
+ return 0;
+}
+
+/* Save the timestamps of sent ('s') and returned ('r') probes in the
+ * ctx->msg.samples[] array. Depending of the context (server or client), there
+ * may be only returned probes, or both sent and returned probes. The returned
+ * probes are saved first in the array, after them are the sent probes.
+ * Depending of the context, the array can be with size:
+ * [0 .. max data.count] - holds only returned probes
+ * [0 .. 2 * max data.count] - holds both returned and sent probes
+ */
+static void ptp_probe_store(struct ptp_markers_context *ctx,
+ struct ptp_marker *marker,
+ unsigned long long ts)
+{
+ int index = -1;
+
+ if (marker->data.packet_id == 'r' &&
+ marker->data.count <= ctx->size) {
+ index = marker->data.count - 1;
+ } else if (marker->data.packet_id == 's' &&
+ marker->data.count * 2 <= ctx->size){
+ index = ctx->size / 2 + marker->data.count - 1;
+ }
+
+ if (index >= 0) {
+ ctx->msg.samples[index].id = marker->data.count;
+ ctx->msg.samples[index].ts = ts;
+ ctx->msg.count++;
+ }
+}
+
+static int ptp_marker_find(struct tep_event *event, struct tep_record *record,
+ int cpu, void *context)
+{
+ struct ptp_markers_context *ctx;
+ struct ptp_marker *marker;
+
+ ctx = (struct ptp_markers_context *)context;
+
+ /* Make sure this is our event */
+ if (event->id != ctx->ptp->raw_id || !ctx->ptp->id)
+ return 0;
+ if (record->size >= (ctx->ptp->id->offset + sizeof(struct ptp_marker))) {
+ marker = (struct ptp_marker *)(record->data + ctx->ptp->id->offset);
+ if (marker->data.local_cid == ctx->clock->local_cid &&
+ marker->data.remote_cid == ctx->clock->remote_cid &&
+ marker->series_id == ctx->ptp->series_id &&
+ marker->data.count)
+ ptp_probe_store(ctx, marker, record->ts);
+ }
+
+ return 0;
+}
+
+static inline bool good_probe(struct ptp_clock_sample *server_sample,
+ struct ptp_clock_sample *send_sample,
+ struct ptp_clock_sample *client_sample,
+ int *bad_probes)
+{
+ if (server_sample->ts && send_sample->ts && client_sample->ts &&
+ server_sample->id == send_sample->id &&
+ server_sample->id == client_sample->id)
+ return true;
+ (*bad_probes)++;
+ return false;
+}
+
+static int ptp_calc_offset_fastest(struct clock_sync_context *clock,
+ struct ptp_clock_result_msg *server,
+ struct ptp_clock_result_msg *client,
+ long long *offset_ret, long long *ts_ret,
+ int *bad_probes)
+{
+ struct ptp_clock_sample *sample_send;
+ long long delta_min = LLONG_MAX;
+ long long offset = 0;
+ long long delta = 0;
+ long long ts = 0;
+ int max_i;
+ int i;
+
+ *bad_probes = 0;
+ sample_send = server->samples + (server->count / 2);
+ max_i = server->count / 2 < client->count ?
+ server->count / 2 : client->count;
+ for (i = 0; i < max_i; i++) {
+ if (!good_probe(&server->samples[i], &sample_send[i],
+ &client->samples[i], bad_probes))
+ continue;
+ ts = (sample_send[i].ts + server->samples[i].ts) / 2;
+ offset = client->samples[i].ts - ts;
+
+ delta = server->samples[i].ts - sample_send[i].ts;
+ if (delta_min > delta) {
+ delta_min = delta;
+ *offset_ret = offset;
+ *ts_ret = ts;
+ }
+#ifdef TSYNC_DEBUG
+ {
+ struct ptp_clock_sync *ptp;
+
+ ptp = (struct ptp_clock_sync *)clock->proto_data;
+ if (ptp && ptp->debug_fd > 0) {
+ char buff[256];
+
+ sprintf(buff, "%lld %lld %lld\n",
+ ts, client->samples[i].ts, offset);
+ write(ptp->debug_fd, buff, strlen(buff));
+ }
+ }
+#endif
+ }
+
+ return 0;
+}
+
+static int ptp_calc_offset_hist(struct clock_sync_context *clock,
+ struct ptp_clock_result_msg *server,
+ struct ptp_clock_result_msg *client,
+ long long *offset_ret, long long *ts_ret,
+ int *bad_probes)
+{
+ struct ptp_clock_sample *sample_send;
+ long long timestamps[PTP_SYNC_LOOP];
+ long long offsets[PTP_SYNC_LOOP];
+ long long offset_min = LLONG_MAX;
+ long long offset_max = 0;
+ int hist[PTP_SYNC_LOOP];
+ int ind, max = 0;
+ long long bin;
+ int i, k = 0;
+
+ *bad_probes = 0;
+ memset(hist, 0, sizeof(int) * PTP_SYNC_LOOP);
+ sample_send = server->samples + (server->count / 2);
+ for (i = 0; i * 2 < server->count && i < client->count; i++) {
+ if (!good_probe(&server->samples[i], &sample_send[i],
+ &client->samples[i], bad_probes))
+ continue;
+ timestamps[k] = (sample_send[i].ts + server->samples[i].ts) / 2;
+ offsets[k] = client->samples[i].ts - timestamps[k];
+ if (offset_max < llabs(offsets[k]))
+ offset_max = llabs(offsets[k]);
+ if (offset_min > llabs(offsets[k]))
+ offset_min = llabs(offsets[k]);
+#ifdef TSYNC_DEBUG
+ {
+ struct ptp_clock_sync *ptp;
+
+ ptp = (struct ptp_clock_sync *)clock->proto_data;
+
+ if (ptp && ptp->debug_fd > 0) {
+ char buff[256];
+
+ sprintf(buff, "%lld %lld %lld\n",
+ timestamps[k],
+ client->samples[i].ts, offsets[k]);
+ write(ptp->debug_fd, buff, strlen(buff));
+ }
+ }
+#endif
+ k++;
+ }
+
+ bin = (offset_max - offset_min) / PTP_SYNC_LOOP;
+ for (i = 0; i < k; i++) {
+ ind = (llabs(offsets[i]) - offset_min) / bin;
+ if (ind < PTP_SYNC_LOOP) {
+ hist[ind]++;
+ if (max < hist[ind]) {
+ max = hist[ind];
+ *offset_ret = offsets[i];
+ *ts_ret = timestamps[i];
+ }
+ }
+ }
+
+ return 0;
+}
+
+static void ntoh_ptp_results(struct ptp_clock_result_msg *msg)
+{
+ int i;
+
+ msg->count = ntohl(msg->count);
+ for (i = 0; i < msg->count; i++) {
+ msg->samples[i].id = ntohl(msg->samples[i].id);
+ msg->samples[i].ts = ntohll(msg->samples[i].ts);
+ }
+ msg->series_id = ntohl(msg->series_id);
+}
+
+
+static void hton_ptp_results(struct ptp_clock_result_msg *msg)
+{
+ int i;
+
+ for (i = 0; i < msg->count; i++) {
+ msg->samples[i].id = htonl(msg->samples[i].id);
+ msg->samples[i].ts = htonll(msg->samples[i].ts);
+ }
+ msg->series_id = htonl(msg->series_id);
+ msg->count = htonl(msg->count);
+}
+
+static inline void ptp_track_clock(struct ptp_markers_context *ctx,
+ struct ptp_marker *marker)
+{
+ if (ctx->ptp->flags & PTP_FLAG_USE_MARKER) {
+ write(ctx->ptp->marker_fd, marker, sizeof(struct ptp_marker));
+ } else {
+ struct timespec clock;
+ unsigned long long ts;
+
+ clock_gettime(CLOCK_MONOTONIC_RAW, &clock);
+ ts = clock.tv_sec * 1000000000LL;
+ ts += clock.tv_nsec;
+ ptp_probe_store(ctx, marker, ts);
+ }
+}
+
+static int ptp_clock_client(struct tracecmd_time_sync *tsync,
+ long long *offset, long long *timestamp)
+{
+ char sync_proto[TRACECMD_TSYNC_PNAME_LENGTH];
+ struct clock_sync_context *clock_context;
+ struct ptp_clock_offset_msg res_offset;
+ struct ptp_clock_start_msg start;
+ struct ptp_markers_context ctx;
+ struct ptp_clock_sync *ptp;
+ struct ptp_marker marker;
+ unsigned int sync_msg;
+ unsigned int size;
+ char *msg;
+ int count;
+ int ret;
+
+ if (!tsync || !tsync->context || !tsync->msg_handle)
+ return -1;
+
+ clock_context = (struct clock_sync_context *)tsync->context;
+ if (clock_context->proto_data == NULL)
+ return -1;
+
+ ptp = (struct ptp_clock_sync *)clock_context->proto_data;
+ size = sizeof(start);
+ msg = (char *)&start;
+ ret = tracecmd_msg_recv_time_sync(tsync->msg_handle,
+ sync_proto, &sync_msg,
+ &size, &msg);
+ if (ret || strncmp(sync_proto, PTP_NAME, TRACECMD_TSYNC_PNAME_LENGTH) ||
+ sync_msg != PTP_SYNC_PKT_START)
+ return -1;
+ ret = tracecmd_msg_send_time_sync(tsync->msg_handle, PTP_NAME,
+ PTP_SYNC_PKT_START, sizeof(start),
+ (char *)&start);
+ marker.data.local_cid = clock_context->local_cid;
+ marker.data.remote_cid = clock_context->remote_cid;
+ marker.series_id = ntohl(start.series_id);
+ marker.data.packet_id = 'r';
+ ptp->series_id = marker.series_id;
+ ptp->flags = ntohl(start.flags);
+ msg = (char *)&count;
+ size = sizeof(count);
+ ctx.msg.count = 0;
+ ctx.size = PTP_SYNC_LOOP;
+ ctx.ptp = ptp;
+ ctx.clock = clock_context;
+ ctx.msg.series_id = ptp->series_id;
+ while (true) {
+ count = 0;
+ ret = tracecmd_msg_recv_time_sync(tsync->msg_handle,
+ sync_proto, &sync_msg,
+ &size, &msg);
+ if (ret || strncmp(sync_proto, PTP_NAME, TRACECMD_TSYNC_PNAME_LENGTH) ||
+ sync_msg != PTP_SYNC_PKT_PROBE || !ntohl(count))
+ break;
+ marker.data.count = ntohl(count);
+ ptp_track_clock(&ctx, &marker);
+ ret = tracecmd_msg_send_time_sync(tsync->msg_handle, PTP_NAME,
+ PTP_SYNC_PKT_PROBE,
+ sizeof(count), (char *)&count);
+ if (ret)
+ break;
+ }
+
+ if (strncmp(sync_proto, PTP_NAME, TRACECMD_TSYNC_PNAME_LENGTH) ||
+ sync_msg != PTP_SYNC_PKT_END)
+ return -1;
+
+ if (ptp->flags & PTP_FLAG_USE_MARKER)
+ tracefs_iterate_raw_events(ptp->tep, clock_context->instance,
+ ptp_marker_find, &ctx);
+
+ hton_ptp_results(&ctx.msg);
+ ret = tracecmd_msg_send_time_sync(tsync->msg_handle, PTP_NAME,
+ PTP_SYNC_PKT_PROBES,
+ sizeof(ctx.msg), (char *)&ctx.msg);
+
+ msg = (char *)&res_offset;
+ size = sizeof(res_offset);
+ ret = tracecmd_msg_recv_time_sync(tsync->msg_handle,
+ sync_proto, &sync_msg,
+ &size, (char **)&msg);
+ if (ret || strncmp(sync_proto, PTP_NAME, TRACECMD_TSYNC_PNAME_LENGTH) ||
+ sync_msg != PTP_SYNC_PKT_OFFSET)
+ return -1;
+
+ *offset = ntohll(res_offset.offset);
+ *timestamp = ntohll(res_offset.ts);
+
+ return 0;
+}
+
+
+static int ptp_clock_server(struct tracecmd_time_sync *tsync,
+ long long *offset, long long *timestamp)
+{
+ char sync_proto[TRACECMD_TSYNC_PNAME_LENGTH];
+ struct ptp_clock_result_msg *results = NULL;
+ struct clock_sync_context *clock_context;
+ struct ptp_clock_offset_msg res_offset;
+ struct ptp_clock_start_msg start;
+ struct ptp_markers_context ctx;
+ int sync_loop = PTP_SYNC_LOOP;
+ struct ptp_clock_sync *ptp;
+ struct ptp_marker marker;
+ unsigned int sync_msg;
+ unsigned int size;
+ int bad_probes;
+ int count = 1;
+ int msg_count;
+ int msg_ret;
+ char *msg;
+ int ret;
+
+ if (!tsync || !tsync->context || !tsync->msg_handle)
+ return -1;
+
+ clock_context = (struct clock_sync_context *)tsync->context;
+ if (clock_context->proto_data == NULL)
+ return -1;
+
+ ptp = (struct ptp_clock_sync *)clock_context->proto_data;
+ ptp->flags = ptp_flags;
+ memset(&start, 0, sizeof(start));
+ start.series_id = htonl(ptp->series_id + 1);
+ start.flags = htonl(ptp->flags);
+ ret = tracecmd_msg_send_time_sync(tsync->msg_handle, PTP_NAME,
+ PTP_SYNC_PKT_START, sizeof(start),
+ (char *)&start);
+ if (!ret)
+ ret = tracecmd_msg_recv_time_sync(tsync->msg_handle,
+ sync_proto, &sync_msg,
+ NULL, NULL);
+ if (ret || strncmp(sync_proto, PTP_NAME, TRACECMD_TSYNC_PNAME_LENGTH) ||
+ sync_msg != PTP_SYNC_PKT_START)
+ return -1;
+
+ tracefs_instance_file_write(clock_context->instance, "trace", "\0");
+
+ ptp->series_id++;
+ marker.data.local_cid = clock_context->local_cid;
+ marker.data.remote_cid = clock_context->remote_cid;
+ marker.series_id = ptp->series_id;
+ msg = (char *)&msg_ret;
+ size = sizeof(msg_ret);
+ ctx.size = 2*PTP_SYNC_LOOP;
+ ctx.ptp = ptp;
+ ctx.clock = clock_context;
+ ctx.msg.count = 0;
+ ctx.msg.series_id = ptp->series_id;
+ do {
+ marker.data.count = count++;
+ marker.data.packet_id = 's';
+ msg_count = htonl(marker.data.count);
+ ptp_track_clock(&ctx, &marker);
+ ret = tracecmd_msg_send_time_sync(tsync->msg_handle, PTP_NAME,
+ PTP_SYNC_PKT_PROBE,
+ sizeof(msg_count),
+ (char *)&msg_count);
+ if (!ret)
+ ret = tracecmd_msg_recv_time_sync(tsync->msg_handle,
+ sync_proto, &sync_msg,
+ &size, &msg);
+
+ marker.data.packet_id = 'r';
+ ptp_track_clock(&ctx, &marker);
+ if (ret || strncmp(sync_proto, PTP_NAME, TRACECMD_TSYNC_PNAME_LENGTH) ||
+ sync_msg != PTP_SYNC_PKT_PROBE ||
+ ntohl(msg_ret) != marker.data.count)
+ break;
+ } while (--sync_loop);
+
+ if (sync_loop)
+ return -1;
+
+ ret = tracecmd_msg_send_time_sync(tsync->msg_handle, PTP_NAME,
+ PTP_SYNC_PKT_END, 0, NULL);
+
+ size = 0;
+ ret = tracecmd_msg_recv_time_sync(tsync->msg_handle,
+ sync_proto, &sync_msg,
+ &size, (char **)&results);
+ if (ret || strncmp(sync_proto, PTP_NAME, TRACECMD_TSYNC_PNAME_LENGTH) ||
+ sync_msg != PTP_SYNC_PKT_PROBES || size == 0 || results == NULL)
+ return -1;
+
+ ntoh_ptp_results(results);
+ if (ptp->flags & PTP_FLAG_USE_MARKER)
+ tracefs_iterate_raw_events(ptp->tep, clock_context->instance,
+ ptp_marker_find, &ctx);
+ if (ptp->flags & PTP_FLAG_FASTEST_RESPONSE)
+ ptp_calc_offset_fastest(clock_context, &ctx.msg, results, offset,
+ timestamp, &bad_probes);
+ else
+ ptp_calc_offset_hist(clock_context, &ctx.msg, results, offset,
+ timestamp, &bad_probes);
+#ifdef TSYNC_DEBUG
+ {
+ char buff[256];
+ int res_fd;
+
+ sprintf(buff, "res-cid%d.txt", clock_context->remote_cid);
+
+ res_fd = open(buff, O_WRONLY|O_APPEND, 0644);
+ if (res_fd > 0) {
+ if (*offset && *timestamp) {
+ sprintf(buff, "%d %lld %lld\n",
+ ptp->series_id, *offset, *timestamp);
+ write(res_fd, buff, strlen(buff));
+ }
+ close(res_fd);
+ }
+
+ printf("\n calculated offset %d: %lld, %d probes, filtered out %d, PTP flags 0x%X\n\r",
+ ptp->series_id, *offset, results->count, bad_probes, ptp->flags);
+ if (ptp && ptp->debug_fd > 0) {
+ sprintf(buff, "%lld %lld 0\n", *offset, *timestamp);
+ write(ptp->debug_fd, buff, strlen(buff));
+ close(ptp->debug_fd);
+ ptp->debug_fd = -1;
+ }
+
+ }
+#endif
+
+ res_offset.offset = htonll(*offset);
+ res_offset.ts = htonll(*timestamp);
+ ret = tracecmd_msg_send_time_sync(tsync->msg_handle, PTP_NAME,
+ PTP_SYNC_PKT_OFFSET,
+ sizeof(res_offset),
+ (char *)&res_offset);
+
+ free(results);
+ return 0;
+}
+
+static int ptp_clock_sync_calc(struct tracecmd_time_sync *tsync,
+ long long *offset, long long *scaling,
+ long long *timestamp, unsigned int cpu)
+{
+ struct clock_sync_context *clock_context;
+ int ret;
+
+ if (!tsync || !tsync->context)
+ return -1;
+ clock_context = (struct clock_sync_context *)tsync->context;
+
+#ifdef TSYNC_DEBUG
+ if (clock_context->is_server) {
+ struct ptp_clock_sync *ptp;
+ char buff[256];
+
+ ptp = (struct ptp_clock_sync *)clock_context->proto_data;
+ if (ptp->debug_fd > 0)
+ close(ptp->debug_fd);
+ sprintf(buff, "s-cid%d_%d.txt",
+ clock_context->remote_cid, ptp->series_id+1);
+ ptp->debug_fd = open(buff, O_CREAT|O_WRONLY|O_TRUNC, 0644);
+ }
+#endif
+
+ if (scaling)
+ *scaling = 1;
+ if (clock_context->is_server)
+ ret = ptp_clock_server(tsync, offset, timestamp);
+ else
+ ret = ptp_clock_client(tsync, offset, timestamp);
+
+ return ret;
+}
+
+int ptp_clock_sync_register(void)
+{
+ return tracecmd_tsync_proto_register(PTP_NAME, PTP_ACCURACY,
+ TRACECMD_TIME_SYNC_ROLE_GUEST |
+ TRACECMD_TIME_SYNC_ROLE_HOST,
+ 0, TRACECMD_TSYNC_FLAG_INTERPOLATE,
+ ptp_clock_sync_init,
+ ptp_clock_sync_free,
+ ptp_clock_sync_calc);
+
+}
+
+int ptp_clock_sync_unregister(void)
+{
+ return tracecmd_tsync_proto_unregister(PTP_NAME);
+}
@@ -64,7 +64,7 @@ static struct tsync_proto *tsync_proto_find(const char *proto_name)
*/
void tracecmd_tsync_init(void)
{
-
+ ptp_clock_sync_register();
}
int tracecmd_tsync_proto_register(const char *proto_name, int accuracy, int roles,
PTP protocol is designed for synchronizing clocks of machines in a local network. The same approach can be used for host - guest timestamp synchronization. This implementation uses ftrace raw markers to track trace timestamps of PTP events. The patch is a POC, two different algorithms for PTP calculations are proposed: - Choosing the sample with the fastest response time for calculating the clocks offset. - Calculating the clocks offset using the average of all PTP samples. The implementation can be tuned using those parameters: - #define FASTEST_RESPONSE - is defined, the sample with the fastest response time is used for calculating the clocks offset. Otherwise the histogram of all samples is used. - #define PTP_SYNC_LOOP 340 - defines the number of samples, used for one calculation. - --tsync-interval - a trace-cmd argument, choose the intervals between offset calculations, performed continuously during the trace. - #define TSYNC_DEBUG - if defined, a debug information is collected and stored in files, in the guest machine: s-cid*.txt - For each offset calculation: host and guest clocks and calculated offset. res-cid*.txt - For each tracing session: all calculated clock offsets. Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> --- lib/trace-cmd/Makefile | 1 + lib/trace-cmd/trace-timesync-ptp.c | 714 +++++++++++++++++++++++++++++ lib/trace-cmd/trace-timesync.c | 2 +- 3 files changed, 716 insertions(+), 1 deletion(-) create mode 100644 lib/trace-cmd/trace-timesync-ptp.c