From: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Date: Tue, 7 Jun 2022 19:50:39 +0000 (-0400)
Subject: Propagate trace format to kernel tracer
X-Git-Url: http://git.efficios.com/?a=commitdiff_plain;h=121b0d1a62dfcb59c401d84ab11ca41a427feacf;p=deliverable%2Flttng-tools.git

Propagate trace format to kernel tracer

Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Change-Id: I9c0ba97bd1dfbf1358f593212926275485a9b64a
---

diff --git a/src/bin/lttng-sessiond/kernel.cpp b/src/bin/lttng-sessiond/kernel.cpp
index 2831a039e..7428e795c 100644
--- a/src/bin/lttng-sessiond/kernel.cpp
+++ b/src/bin/lttng-sessiond/kernel.cpp
@@ -164,6 +164,11 @@ int kernel_create_session(struct ltt_session *session)
 			session->id, session->name);
 	}
 
+	ret = kernctl_session_set_trace_format(lks->fd, *session->trace_format);
+	if (ret) {
+		WARN("Could not set kernel session trace format %" PRIu64 " name: %s", session->id,
+				session->name);
+	}
 	return 0;
 
 error:
diff --git a/src/common/kernel-ctl/kernel-ctl.cpp b/src/common/kernel-ctl/kernel-ctl.cpp
index 76960307c..f9264476e 100644
--- a/src/common/kernel-ctl/kernel-ctl.cpp
+++ b/src/common/kernel-ctl/kernel-ctl.cpp
@@ -379,6 +379,39 @@ end:
 	return ret;
 }
 
+int kernctl_session_set_trace_format(int fd, const lttng::trace_format_descriptor& trace_format)
+{
+	int ret;
+	struct lttng_kernel_abi_session_trace_format k_trace_format;
+
+	switch (trace_format.type()) {
+	case LTTNG_TRACE_FORMAT_DESCRIPTOR_TYPE_CTF_1:
+		k_trace_format.type = (uint32_t) LTTNG_KERNEL_ABI_TRACE_FORMAT_CTF1;
+		break;
+	case LTTNG_TRACE_FORMAT_DESCRIPTOR_TYPE_CTF_2:
+		k_trace_format.type = (uint32_t) LTTNG_KERNEL_ABI_TRACE_FORMAT_CTF2;
+		break;
+	case LTTNG_TRACE_FORMAT_DESCRIPTOR_TYPE_UNKNOWN:
+		/* Fallthrougth */
+	default:
+		ret = -EINVAL;
+		goto end;
+	}
+
+	ret = LTTNG_IOCTL_CHECK(fd, LTTNG_KERNEL_ABI_SESSION_SET_TRACE_FORMAT, &k_trace_format);
+	if (ret == -ENOSYS) {
+		if (trace_format.type() != LTTNG_TRACE_FORMAT_DESCRIPTOR_TYPE_CTF_1) {
+			/* Must never happen based on earlier error check */
+			abort();
+		} else {
+			/* Old modules default to ctf1 format. */
+			ret = 0;
+		}
+	}
+
+end:
+	return ret;
+}
 int kernctl_create_stream(int fd)
 {
 	return compat_ioctl_no_arg(fd, LTTNG_KERNEL_ABI_OLD_STREAM,
diff --git a/src/common/kernel-ctl/kernel-ctl.hpp b/src/common/kernel-ctl/kernel-ctl.hpp
index 4f47488b5..c47ebad7f 100644
--- a/src/common/kernel-ctl/kernel-ctl.hpp
+++ b/src/common/kernel-ctl/kernel-ctl.hpp
@@ -11,10 +11,11 @@
 
 #include <stdbool.h>
 
-#include <lttng/lttng.h>
-#include <common/lttng-kernel.hpp>
 #include <common/lttng-kernel-old.hpp>
-#include <common/sessiond-comm/sessiond-comm.hpp>	/* for struct lttng_filter_bytecode */
+#include <common/lttng-kernel.hpp>
+#include <common/sessiond-comm/sessiond-comm.hpp> /* for struct lttng_filter_bytecode */
+#include <lttng/lttng.h>
+#include <lttng/trace-format-descriptor-internal.hpp>
 
 int kernctl_create_session(int fd);
 int kernctl_open_metadata(int fd, struct lttng_channel_attr *chops);
@@ -81,6 +82,7 @@ int kernctl_session_regenerate_metadata(int fd);
 int kernctl_session_regenerate_statedump(int fd);
 int kernctl_session_set_name(int fd, const char *name);
 int kernctl_session_set_creation_time(int fd, time_t time);
+int kernctl_session_set_trace_format(int fd, const lttng::trace_format_descriptor& trace_format);
 
 /* Buffer operations */
 
diff --git a/src/common/kernel-ctl/kernel-ioctl.hpp b/src/common/kernel-ctl/kernel-ioctl.hpp
index 68bcc472c..95baec6bf 100644
--- a/src/common/kernel-ctl/kernel-ioctl.hpp
+++ b/src/common/kernel-ctl/kernel-ioctl.hpp
@@ -144,6 +144,8 @@
 	_IOW(0xF6, 0x5D, struct lttng_kernel_abi_session_name)
 #define LTTNG_KERNEL_ABI_SESSION_SET_CREATION_TIME		\
 	_IOW(0xF6, 0x5E, struct lttng_kernel_abi_session_creation_time)
+#define LTTNG_KERNEL_ABI_SESSION_SET_TRACE_FORMAT \
+	_IOW(0xF6, 0x5F, struct lttng_kernel_abi_session_trace_format)
 
 /* Channel FD ioctl */
 #define LTTNG_KERNEL_ABI_STREAM			_IO(0xF6, 0x62)
diff --git a/src/common/lttng-kernel.hpp b/src/common/lttng-kernel.hpp
index 6b1f7985d..02bcffe78 100644
--- a/src/common/lttng-kernel.hpp
+++ b/src/common/lttng-kernel.hpp
@@ -331,4 +331,13 @@ struct lttng_kernel_abi_tracker_args {
 	int32_t id;
 };
 
+enum lttng_kernel_abi_trace_format_type {
+	LTTNG_KERNEL_ABI_TRACE_FORMAT_CTF1 = 0,
+	LTTNG_KERNEL_ABI_TRACE_FORMAT_CTF2 = 1,
+};
+
+struct lttng_kernel_abi_session_trace_format {
+	uint32_t type; /* enum lttng_kernel_abi_trace_format_type */
+} LTTNG_PACKED;
+
 #endif /* _LTTNG_KERNEL_H */