callstack context: use delimiter when stack is incomplete

[lttng-modules.git] / lttng-context-hostname.c

diff --git a/lttng-context-hostname.c b/lttng-context-hostname.c
index 15aabe63c3f18bb31800f9b7ed61fc14dd6a859d..791fed4618f48a025ef1c543087dcb4cd5d1ac3e 100644 (file)
--- a/lttng-context-hostname.c
+++ b/lttng-context-hostname.c
@@ -24,10 +24,10 @@
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/utsname.h>
-#include "lttng-events.h"
-#include "wrapper/ringbuffer/frontend_types.h"
-#include "wrapper/vmalloc.h"
-#include "lttng-tracer.h"
+#include <lttng-events.h>
+#include <wrapper/ringbuffer/frontend_types.h>
+#include <wrapper/vmalloc.h>
+#include <lttng-tracer.h>
 
 #define LTTNG_HOSTNAME_CTX_LEN (__NEW_UTS_LEN + 1)
 
@@ -65,6 +65,29 @@ void hostname_record(struct lttng_ctx_field *field,
        }
 }
 
+static
+void hostname_get_value(struct lttng_ctx_field *field,
+               struct lttng_probe_ctx *lttng_probe_ctx,
+               union lttng_ctx_value *value)
+{
+       struct nsproxy *nsproxy;
+       struct uts_namespace *ns;
+       char *hostname;
+
+       /*
+        * No need to take the RCU read-side lock to read current
+        * nsproxy. (documented in nsproxy.h)
+        */
+       nsproxy = current->nsproxy;
+       if (nsproxy) {
+               ns = nsproxy->uts_ns;
+               hostname = ns->name.nodename;
+       } else {
+               hostname = "";
+       }
+       value->str = hostname;
+}
+
 int lttng_add_hostname_to_ctx(struct lttng_ctx **ctx)
 {
        struct lttng_ctx_field *field;
@@ -89,16 +112,9 @@ int lttng_add_hostname_to_ctx(struct lttng_ctx **ctx)
 
        field->get_size = hostname_get_size;
        field->record = hostname_record;
+       field->get_value = hostname_get_value;
        lttng_context_update(*ctx);
        wrapper_vmalloc_sync_all();
        return 0;
 }
 EXPORT_SYMBOL_GPL(lttng_add_hostname_to_ctx);
-
-MODULE_LICENSE("GPL and additional rights");
-MODULE_AUTHOR("Mathieu Desnoyers");
-MODULE_DESCRIPTION("Linux Trace Toolkit Perf Support");
-MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
-       __stringify(LTTNG_MODULES_MINOR_VERSION) "."
-       __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
-       LTTNG_MODULES_EXTRAVERSION);