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:
Guest name, null terminated string
long long (8 bytes) trace-id
int (4 bytes) number of guest CPUs
array of size number of guest CPUs:
int (4 bytes) Guest CPU id
int (4 bytes) Host PID, running the guest CPU
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@xxxxxxxxx>
---
include/trace-cmd/trace-cmd.h | 5 ++
lib/trace-cmd/trace-input.c | 128 ++++++++++++++++++++++++++++++++++
tracecmd/trace-dump.c | 62 ++++++++++++++++
tracecmd/trace-record.c | 61 ++++++++++++++++
4 files changed, 256 insertions(+)
diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index ac46637e..0375f500 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -111,6 +111,7 @@ enum {
TRACECMD_OPTION_PROCMAPS,
TRACECMD_OPTION_TRACEID,
TRACECMD_OPTION_TIME_SHIFT,
+ TRACECMD_OPTION_GUEST,
};
enum {
@@ -154,6 +155,10 @@ void tracecmd_set_flag(struct tracecmd_input *handle, int flag);
void tracecmd_clear_flag(struct tracecmd_input *handle, int flag);
unsigned long tracecmd_get_flags(struct tracecmd_input *handle);
unsigned long long tracecmd_get_traceid(struct tracecmd_input *handle);
+int tracecmd_get_guest_cpumap(struct tracecmd_input *handle,
+ unsigned long long trace_id,
+ char **name,
+ int *vcpu_count, int **cpu_pid);
unsigned long long tracecmd_get_tsync_peer(struct tracecmd_input *handle);
int tracecmd_enable_tsync(struct tracecmd_input *handle, bool enable);
diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index 2f0274d9..01a1def4 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -82,6 +82,14 @@ 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;
@@ -115,6 +123,7 @@ struct tracecmd_input {
char * trace_clock;
struct input_buffer_instance *buffers;
int parsing_failures;
+ struct guest_trace_info *guest;
struct tracecmd_ftrace finfo;
@@ -2197,6 +2206,86 @@ static void procmap_free(struct pid_addr_maps *maps)
free(maps);
}
+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, int size)
+{
+ struct guest_trace_info *guest = NULL;
+ int cpu;
+ int i;
+
+ guest = calloc(1, sizeof(struct guest_trace_info));
+ if (!guest)
+ goto error;
+
+ /*
+ * Guest name, null terminated string
+ * long long (8 bytes) trace-id
+ * int (4 bytes) number of guest CPUs
+ * array of size number of guest CPUs:
+ * int (4 bytes) Guest CPU id
+ * int (4 bytes) Host PID, running the guest CPU
+ */
+
+ guest->name = strndup(buf, size);
+ if (!guest->name)
+ goto error;
+ buf += strlen(guest->name) + 1;
+ size -= strlen(guest->name) + 1;
+
+ if (size < sizeof(long long))
+ goto error;
+ guest->trace_id = tep_read_number(handle->pevent, buf, sizeof(long long));
+ buf += sizeof(long long);
+ size -= sizeof(long long);
+
+ if (size < sizeof(int))
+ goto error;
+ guest->vcpu_count = tep_read_number(handle->pevent, buf, sizeof(int));
+ buf += sizeof(int);
+ size -= sizeof(int);
+
+ guest->cpu_pid = calloc(guest->vcpu_count, sizeof(int));
+ if (!guest->cpu_pid)
+ goto error;
+
+ for (i = 0; i < guest->vcpu_count; i++) {
+ if (size < 2 * sizeof(int))
+ goto error;
+ cpu = tep_read_number(handle->pevent, buf, sizeof(int));
+ buf += sizeof(int);
+ if (cpu >= guest->vcpu_count)
+ goto error;
+ guest->cpu_pid[cpu] = tep_read_number(handle->pevent,
+ buf, sizeof(int));
+ buf += sizeof(int);
+ size -= 2 * sizeof(int);
+ }
+
+ guest->next = handle->guest;
+ handle->guest = guest;
+ return 0;
+
+error:
+ if (guest) {
+ free(guest->cpu_pid);
+ free(guest->name);
+ free(guest);
+ }
+ return -1;
+}
+
/* Needs to be a constant, and 4K should be good enough */
#define STR_PROCMAP_LINE_MAX 4096
static int trace_pid_map_load(struct tracecmd_input *handle, char *buf)
@@ -2468,6 +2557,9 @@ static int handle_options(struct tracecmd_input *handle)
handle->trace_id = tep_read_number(handle->pevent,
&cpus, 8);
break;
+ case TRACECMD_OPTION_GUEST:
+ trace_guest_load(handle, buf, size);
+ break;
default:
warning("unknown option %d", option);
break;
@@ -3122,6 +3214,7 @@ 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);
@@ -3586,6 +3679,41 @@ 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
+ * @name: return, name of the guest
+ * @vcpu_count: return, number of VPUs
+ * @cpu_pid: return, array with guest VCPU to host process mapping
+ *
+ * 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-dump.c b/tracecmd/trace-dump.c
index b4beb8b2..ffb1c6b1 100644
--- a/tracecmd/trace-dump.c
+++ b/tracecmd/trace-dump.c
@@ -412,6 +412,65 @@ out:
free(offsets);
}
+void dump_option_guest(int fd, int size)
+{
+ unsigned long long trace_id;
+ char *buf, *p;
+ int cpu, pid;
+ int cpus;
+ int i;
+
+ do_print(OPTIONS, "\t\t[Option GUEST, %d bytes]\n", size);
+
+ /*
+ * Guest name, null terminated string
+ * long long (8 bytes) trace-id
+ * int (4 bytes) number of guest CPUs
+ * array of size number of guest CPUs:
+ * int (4 bytes) Guest CPU id
+ * int (4 bytes) Host PID, running the guest CPU
+ */
+ buf = calloc(1, size);
+ if (!buf)
+ return;
+ if (read_file_bytes(fd, buf, size))
+ goto out;
+
+ p = buf;
+ do_print(OPTIONS, "%s [Guest name]\n", p);
+ size -= strlen(buf) + 1;
+ p += strlen(buf) + 1;
+
+ if (size < sizeof(long long))
+ goto out;
+ trace_id = tep_read_number(tep, p, sizeof(long long));
+ size -= sizeof(long long);
+ p += sizeof(long long);
+ do_print(OPTIONS, "0x%llX [trace id]\n", trace_id);
+
+ if (size < sizeof(int))
+ goto out;
+ cpus = tep_read_number(tep, p, sizeof(int));
+ size -= sizeof(int);
+ p += sizeof(int);
+ do_print(OPTIONS, "%d [Guest CPUs]\n", cpus);
+
+ for (i = 0; i < cpus; i++) {
+ if (size < 2 * sizeof(int))
+ goto out;
+ cpu = tep_read_number(tep, p, sizeof(int));
+ size -= sizeof(int);
+ p += sizeof(int);
+ pid = tep_read_number(tep, p, sizeof(int));
+ size -= sizeof(int);
+ p += sizeof(int);
+ do_print(OPTIONS, " %d %d [guest cpu, host pid]\n", cpu, pid);
+ }
+
+out:
+ free(buf);
+}
+
static void dump_options(int fd)
{
unsigned short option;
@@ -468,6 +527,9 @@ static void dump_options(int fd)
case TRACECMD_OPTION_TIME_SHIFT:
dump_option_timeshift(fd, size);
break;
+ case TRACECMD_OPTION_GUEST:
+ dump_option_guest(fd, size);
+ break;
default:
do_print(OPTIONS, " %d %d\t[Unknown option, size - skipping]\n",
option, size);
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index b55f407c..15cae9be 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -3061,6 +3061,19 @@ static int set_vcpu_pid_mapping(struct guest *guest, int cpu, int pid)
return 0;
}
+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;
@@ -3874,6 +3887,49 @@ 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);
+ char *buf, *p;
+ int size;
+ int i;
+
+ if (!guest)
+ return;
+ for (i = 0; i < guest->cpu_max; i++)
+ if (!guest->cpu_pid[i])
+ break;
+
+ size = strlen(guest->name) + 1;
+ size += sizeof(long long); /* trace_id */
+ size += sizeof(int); /* cpu count */
+ size += i * 2 * sizeof(int); /* cpu,pid pair */
+
+ buf = calloc(1, size);
+ if (!buf)
+ return;
+ p = buf;
+ strcpy(p, guest->name);
+ p += strlen(guest->name) + 1;
+
+ memcpy(p, &instance->trace_id, sizeof(long long));
+ p += sizeof(long long);
+
+ memcpy(p, &i, sizeof(int));
+ p += sizeof(int);
+ for (i = 0; i < guest->cpu_max; i++) {
+ if (!guest->cpu_pid[i])
+ break;
+ memcpy(p, &i, sizeof(int));
+ p += sizeof(int);
+ memcpy(p, &guest->cpu_pid[i], sizeof(int));
+ p += sizeof(int);
+ }
+
+ tracecmd_add_option(handle, TRACECMD_OPTION_GUEST, size, buf);
+ free(buf);
+}
static void
add_pid_maps(struct tracecmd_output *handle, struct buffer_instance *instance)
@@ -4158,6 +4214,11 @@ 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++)
--
2.24.1
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