New trace.dat option is introduced: TRACECMD_OPTION_GUEST.
Written in the host's trace.dat file, it contains information about
guests, traced at the same time: guest trace ID, number of VCPUs and
PIDs of the host tasks, running those VCPU. The data is stored in
the file as NULL terminated string:
"Guest %s %llu %d\n" -> guest name, number of VCPUs
"%d %d\n" -> VCPU, PID of host task
.....
"%d %d\n" -> VCPU, PID of host task
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@xxxxxxxxx>
---
include/trace-cmd/trace-cmd.h | 1 +
lib/trace-cmd/trace-input.c | 113 ++++++++++++++++++++++++++++++++++
tracecmd/trace-record.c | 45 ++++++++++++++
3 files changed, 159 insertions(+)
diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index 1240b4a..17badf2 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -88,6 +88,7 @@ enum {
TRACECMD_OPTION_PROCMAPS,
TRACECMD_OPTION_TRACEID,
TRACECMD_OPTION_TIME_SHIFT,
+ TRACECMD_OPTION_GUEST,
};
enum {
diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index a6b675a..e36ebaa 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -79,6 +79,14 @@ struct ts_offset_sample {
long long offset;
};
+struct guest_trace_info {
+ struct guest_trace_info *next;
+ char *name;
+ unsigned long long trace_id;
+ int vcpu_count;
+ int *cpu_pid;
+};
+
struct host_trace_info {
bool sync_enable;
unsigned long long trace_id;
@@ -112,6 +120,7 @@ struct tracecmd_input {
char * trace_clock;
struct input_buffer_instance *buffers;
int parsing_failures;
+ struct guest_trace_info *guest;
struct tracecmd_ftrace finfo;
@@ -2294,6 +2303,73 @@ static int trace_traceid_load(struct tracecmd_input *handle, char *buf)
return -1;
}
+static void trace_guests_free(struct tracecmd_input *handle)
+{
+ struct guest_trace_info *guest;
+
+ while (handle->guest) {
+ guest = handle->guest;
+ handle->guest = handle->guest->next;
+ free(guest->name);
+ free(guest->cpu_pid);
+ free(guest);
+ }
+}
+
+static int trace_guest_load(struct tracecmd_input *handle, char *buf)
+{
+ struct guest_trace_info *guest = NULL;
+ unsigned long long tid;
+ char *line;
+ int cpu, pid;
+
+ line = strchr(buf, '\n');
+ if (!line)
+ goto error;
+ *line = '\0';
+
+ guest = calloc(1, sizeof(struct guest_trace_info));
+ if (!guest)
+ goto error;
+
+ if (sscanf(buf, "%*s %ms %llu %d", &guest->name, &tid, &cpu) != 3)
+ goto error;
+ guest->trace_id = tid;
+ guest->vcpu_count = cpu;
+
+ guest->cpu_pid = calloc(guest->vcpu_count, sizeof(int));
+ if (!guest->cpu_pid)
+ goto error;
+
+ buf = line + 1;
+ line = strchr(buf, '\n');
+ while (line) {
+ *line = '\0';
+ if (sscanf(buf, "%d %d", &cpu, &pid) != 2)
+ goto error;
+
+ if (cpu < guest->vcpu_count)
+ guest->cpu_pid[cpu] = pid;
+ buf = line + 1;
+ if (!*buf)
+ break;
+
+ line = strchr(buf, '\n');
+ }
+
+ guest->next = handle->guest;
+ handle->guest = guest;
+ return 0;
+
+error:
+ if (guest) {
+ free(guest->cpu_pid);
+ free(guest->name);
+ free(guest);
+ }
+ return -1;
+}
+
#define STR_PROCMAP_LINE_MAX (PATH_MAX+22)
static int trace_pid_map_load(struct tracecmd_input *handle, char *buf)
{
@@ -2558,6 +2634,10 @@ static int handle_options(struct tracecmd_input *handle)
if (buf[size-1] == '\0')
trace_traceid_load(handle, buf);
break;
+ case TRACECMD_OPTION_GUEST:
+ if (buf[size-1] == '\0')
+ trace_guest_load(handle, buf);
+ break;
default:
warning("unknown option %d", option);
break;
@@ -3217,6 +3297,7 @@ void tracecmd_close(struct tracecmd_input *handle)
handle->pid_maps = NULL;
trace_tsync_offset_free(&handle->host);
+ trace_guests_free(handle);
if (handle->flags & TRACECMD_FL_BUFFER_INSTANCE)
tracecmd_close(handle->parent);
@@ -3673,6 +3754,38 @@ unsigned long long tracecmd_get_traceid(struct tracecmd_input *handle)
return handle->trace_id;
}
+/**
+ * tracecmd_get_guest_cpumap - get the mapping of guest VCPU to host process
+ * @handle: input handle for the trace.dat file
+ * @trace_id: ID of the guest tracing session
+ *
+ * Returns @name of the guest, number of VPUs (@vcpu_count)
+ * and array @cpu_pid with size @vcpu_count. Array index is VCPU id, array
+ * content is PID of the host process, running this VCPU.
+ *
+ * This information is stored in host trace.dat file
+ */
+int tracecmd_get_guest_cpumap(struct tracecmd_input *handle,
+ unsigned long long trace_id,
+ char *name,
+ int *vcpu_count, int *cpu_pid)
+{
+ struct guest_trace_info *guest = handle->guest;
+
+ while (guest) {
+ if (guest->trace_id == trace_id)
+ break;
+ guest = guest->next;
+ }
+ if (!guest)
+ return -1;
+
+ name = guest->name;
+ *vcpu_count = guest->vcpu_count;
+ cpu_pid = guest->cpu_pid;
+ return 0;
+}
+
/**
* tracecmd_get_tsync_peer - get the trace session id of the peer host
* @handle: input handle for the trace.dat file
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index e51134f..49730d6 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -2884,6 +2884,19 @@ struct guest {
static struct guest *guests;
static size_t guests_len;
+static struct guest *get_guest_info(unsigned int guest_cid)
+{
+ int i;
+
+ if (!guests)
+ return NULL;
+
+ for (i = 0; i < guests_len; i++)
+ if (guest_cid == guests[i].cid)
+ return guests + i;
+ return NULL;
+}
+
static char *get_qemu_guest_name(char *arg)
{
char *tok, *end = arg;
@@ -3689,6 +3702,33 @@ static void append_buffer(struct tracecmd_output *handle,
}
}
+static void
+add_guest_info(struct tracecmd_output *handle, struct buffer_instance *instance)
+{
+ struct guest *guest = get_guest_info(instance->cid);
+ struct trace_seq s;
+ int i;
+
+ if (!guest)
+ return;
+ for (i = 0; i < VCPUS_MAX; i++)
+ if (!guest->cpu_pid[i])
+ break;
+
+ trace_seq_init(&s);
+
+ trace_seq_printf(&s, "Guest %s %llu %d\n",
+ guest->name, instance->trace_id, i);
+ for (i = 0; i < VCPUS_MAX; i++) {
+ if (!guest->cpu_pid[i])
+ break;
+ trace_seq_printf(&s, "%d %d\n", i, guest->cpu_pid[i]);
+ }
+ trace_seq_terminate(&s);
+ tracecmd_add_option(handle, TRACECMD_OPTION_GUEST,
+ s.len + 1, s.buffer);
+ trace_seq_destroy(&s);
+}
static void
add_pid_maps(struct tracecmd_output *handle, struct buffer_instance *instance)
@@ -3976,6 +4016,11 @@ static void record_data(struct common_record_context *ctx)
add_pid_maps(handle, instance);
}
+ for_all_instances(instance) {
+ if (is_guest(instance))
+ add_guest_info(handle, instance);
+ }
+
tracecmd_append_cpu_data(handle, local_cpu_count, temp_files);
for (i = 0; i < max_cpu_count; i++)
--
2.23.0
|