X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fkernel.cpp;h=5b4fc086bde52ce333f8cf72cf9f3d627b0cc000;hp=ba82045ed86e51c18629efbbfe3a1711cd5a3dac;hb=HEAD;hpb=49cddecdbb1e042877ca3855b177ade68151030f

diff --git a/src/bin/lttng-sessiond/kernel.cpp b/src/bin/lttng-sessiond/kernel.cpp
index ba82045ed..4cc51a279 100644
--- a/src/bin/lttng-sessiond/kernel.cpp
+++ b/src/bin/lttng-sessiond/kernel.cpp
@@ -24,6 +24,7 @@
 #include <common/hashtable/utils.hpp>
 #include <common/kernel-ctl/kernel-ctl.hpp>
 #include <common/kernel-ctl/kernel-ioctl.hpp>
+#include <common/scope-exit.hpp>
 #include <common/sessiond-comm/sessiond-comm.hpp>
 #include <common/trace-chunk.hpp>
 #include <common/tracker.hpp>
@@ -49,21 +50,47 @@
 #include <sys/types.h>
 #include <unistd.h>
 
+namespace {
 /*
  * Key used to reference a channel between the sessiond and the consumer. This
  * is only read and updated with the session_list lock held.
  */
-static uint64_t next_kernel_channel_key;
+uint64_t next_kernel_channel_key;
 
-static const char *module_proc_lttng = "/proc/lttng";
+const char *module_proc_lttng = "/proc/lttng";
 
-static int kernel_tracer_fd = -1;
-static nonstd::optional<enum lttng_kernel_tracer_status> kernel_tracer_status = nonstd::nullopt;
-static int kernel_tracer_event_notifier_group_fd = -1;
-static int kernel_tracer_event_notifier_group_notification_fd = -1;
-static struct cds_lfht *kernel_token_to_event_notifier_rule_ht;
+int kernel_tracer_fd = -1;
+nonstd::optional<enum lttng_kernel_tracer_status> kernel_tracer_status = nonstd::nullopt;
+int kernel_tracer_event_notifier_group_fd = -1;
+int kernel_tracer_event_notifier_group_notification_fd = -1;
+struct cds_lfht *kernel_token_to_event_notifier_rule_ht;
+
+const char *kernel_tracer_status_to_str(lttng_kernel_tracer_status status)
+{
+	switch (status) {
+	case LTTNG_KERNEL_TRACER_STATUS_INITIALIZED:
+		return "LTTNG_KERNEL_TRACER_STATUS_INITIALIZED";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_UNKNOWN:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_UNKNOWN";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_NEED_ROOT:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_NEED_ROOT";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_NOTIFIER:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_NOTIFIER";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_OPEN_PROC_LTTNG:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_OPEN_PROC_LTTNG";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_VERSION_MISMATCH:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_VERSION_MISMATCH";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_MODULES_UNKNOWN:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_MODULES_UNKNOWN";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_MODULES_MISSING:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_MODULES_MISSING";
+	case LTTNG_KERNEL_TRACER_STATUS_ERR_MODULES_SIGNATURE:
+		return "LTTNG_KERNEL_TRACER_STATUS_ERR_MODULES_SIGNATURE";
+	}
+
+	abort();
+}
 
-namespace {
 /*
  * On some architectures, calling convention details are embedded in the symbol
  * addresses. Uprobe requires a "clean" symbol offset (or at least, an address
@@ -2000,6 +2027,11 @@ int init_kernel_tracer()
 	int ret;
 	bool is_root = !getuid();
 
+	const auto log_status_on_exit = lttng::make_scope_exit([]() noexcept {
+		DBG_FMT("Kernel tracer status set to `{}`",
+			kernel_tracer_status_to_str(*kernel_tracer_status));
+	});
+
 	/* Modprobe lttng kernel modules */
 	ret = modprobe_lttng_control();
 	if (ret < 0) {
@@ -2094,7 +2126,8 @@ int init_kernel_tracer()
 		    "work for this session daemon.");
 	}
 
-	kernel_tracer_status = nonstd::optional<enum lttng_kernel_tracer_status>(LTTNG_KERNEL_TRACER_STATUS_INITIALIZED);
+	kernel_tracer_status = nonstd::optional<enum lttng_kernel_tracer_status>(
+		LTTNG_KERNEL_TRACER_STATUS_INITIALIZED);
 	return 0;
 
 error_version: