[02/26] trace-cmd: Move add_guest_info() into trace-vm.c

Commit Message

Steven Rostedt May 14, 2022, 2:47 a.m. UTC

From: "Steven Rostedt (Google)" <[e-mail]>

In preparation for the agent proxy, move add_guest_info() into trace-vm.c
and rename it to trace_add_guest_info(). This will be used by the agent
when acting as a proxy.

Also comment the function to state what it does and what it records into
the trace.dat option.

Signed-off-by: Steven Rostedt (Google) <[e-mail]>
---
 tracecmd/include/trace-local.h |  1 +
 tracecmd/trace-record.c        | 54 +-----------------------------
 tracecmd/trace-vm.c            | 61 ++++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 53 deletions(-)

Patch

diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h
index e3fec1319880..f3b805fa7bad 100644
--- a/tracecmd/include/trace-local.h
+++ b/tracecmd/include/trace-local.h
@@ -339,6 +339,7 @@  bool trace_have_guests_pid(void);
 void read_qemu_guests(void);
 int get_guest_pid(unsigned int guest_cid);
 int get_guest_vcpu_pid(unsigned int guest_cid, unsigned int guest_vcpu);
+void trace_add_guest_info(struct tracecmd_output *handle, struct buffer_instance *instance);
 
 /* moved from trace-cmd.h */
 void tracecmd_remove_instances(void);
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index a22935263625..67ad1208f90c 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -4297,58 +4297,6 @@  static void append_buffer(struct tracecmd_output *handle,
 	}
 }
 
-static void
-add_guest_info(struct tracecmd_output *handle, struct buffer_instance *instance)
-{
-	struct trace_guest *guest;
-	const char *name;
-	char *buf, *p;
-	int size;
-	int pid;
-	int i;
-
-	if (is_network(instance)) {
-		name = instance->name;
-	} else {
-		guest = trace_get_guest(instance->cid, NULL);
-		if (!guest)
-			return;
-		name = guest->name;
-	}
-
-	size = strlen(name) + 1;
-	size += sizeof(long long);	/* trace_id */
-	size += sizeof(int);		/* cpu count */
-	size += instance->cpu_count * 2 * sizeof(int);	/* cpu,pid pair */
-
-	buf = calloc(1, size);
-	if (!buf)
-		return;
-	p = buf;
-	strcpy(p, name);
-	p += strlen(name) + 1;
-
-	memcpy(p, &instance->trace_id, sizeof(long long));
-	p += sizeof(long long);
-
-	memcpy(p, &instance->cpu_count, sizeof(int));
-	p += sizeof(int);
-	for (i = 0; i < instance->cpu_count; i++) {
-		pid = -1;
-		if (!is_network(instance)) {
-			if (i < guest->cpu_max)
-				pid = guest->cpu_pid[i];
-		}
-		memcpy(p, &i, sizeof(int));
-		p += sizeof(int);
-		memcpy(p, &pid, 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)
 {
@@ -4679,7 +4627,7 @@  static void record_data(struct common_record_context *ctx)
 
 		for_all_instances(instance) {
 			if (is_guest(instance))
-				add_guest_info(handle, instance);
+				trace_add_guest_info(handle, instance);
 		}
 
 		if (ctx->tsc2nsec.mult) {
diff --git a/tracecmd/trace-vm.c b/tracecmd/trace-vm.c
index 57dbef8d42e4..47f8d96a4015 100644
--- a/tracecmd/trace-vm.c
+++ b/tracecmd/trace-vm.c
@@ -386,3 +386,64 @@  int get_guest_vcpu_pid(unsigned int guest_cid, unsigned int guest_vcpu)
 	}
 	return -1;
 }
+
+/**
+ * trace_add_guest_info - Add the guest info into the trace file option
+ * @handle: The file handle that the guest info option is added to
+ * @instance: The instance that that represents the guest
+ *
+ * Adds information about the guest from the @instance into an option
+ * for the @instance. It records the trace_id, the number of CPUs,
+ * as well as the PIDs of the host that represent the CPUs.
+ */
+void
+trace_add_guest_info(struct tracecmd_output *handle, struct buffer_instance *instance)
+{
+	struct trace_guest *guest;
+	const char *name;
+	char *buf, *p;
+	int size;
+	int pid;
+	int i;
+
+	if (is_network(instance)) {
+		name = instance->name;
+	} else {
+		guest = trace_get_guest(instance->cid, NULL);
+		if (!guest)
+			return;
+		name = guest->name;
+	}
+
+	size = strlen(name) + 1;
+	size += sizeof(long long);	/* trace_id */
+	size += sizeof(int);		/* cpu count */
+	size += instance->cpu_count * 2 * sizeof(int);	/* cpu,pid pair */
+
+	buf = calloc(1, size);
+	if (!buf)
+		return;
+	p = buf;
+	strcpy(p, name);
+	p += strlen(name) + 1;
+
+	memcpy(p, &instance->trace_id, sizeof(long long));
+	p += sizeof(long long);
+
+	memcpy(p, &instance->cpu_count, sizeof(int));
+	p += sizeof(int);
+	for (i = 0; i < instance->cpu_count; i++) {
+		pid = -1;
+		if (!is_network(instance)) {
+			if (i < guest->cpu_max)
+				pid = guest->cpu_pid[i];
+		}
+		memcpy(p, &i, sizeof(int));
+		p += sizeof(int);
+		memcpy(p, &pid, sizeof(int));
+		p += sizeof(int);
+	}
+
+	tracecmd_add_option(handle, TRACECMD_OPTION_GUEST, size, buf);
+	free(buf);
+}