X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=lttng-context-prio.c;h=842717ca7c74def7f4368aae807083c5b2b34666;hb=09fec6b43d11b3e0ece36f9e9e44b9627c1b565d;hp=a62685f7dc7d7fe578a592097b1b02642fb881ed;hpb=8fefc8a2d93a06a032c7983cf621ab3fb0c2acde;p=lttng-modules.git

diff --git a/lttng-context-prio.c b/lttng-context-prio.c
index a62685f7..842717ca 100644
--- a/lttng-context-prio.c
+++ b/lttng-context-prio.c
@@ -15,6 +15,19 @@
 #include "wrapper/vmalloc.h"
 #include "ltt-tracer.h"
 
+static
+int (*wrapper_task_prio_sym)(struct task_struct *t);
+
+int wrapper_task_prio_init(void)
+{
+	wrapper_task_prio_sym = (void *) kallsyms_lookup_name("task_prio");
+	if (!wrapper_task_prio_sym) {
+		printk(KERN_WARNING "LTTng: task_prio symbol lookup failed.\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
 static
 size_t prio_get_size(size_t offset)
 {
@@ -42,9 +55,15 @@ int lttng_add_prio_to_ctx(struct lttng_ctx **ctx)
 	struct lttng_ctx_field *field;
 	int ret;
 
+	if (!wrapper_task_prio_sym) {
+		ret = wrapper_task_prio_init();
+		if (ret)
+			return ret;
+	}
+
 	field = lttng_append_context(ctx);
 	if (!field)
-		return ret;
+		return -ENOMEM;
 	field->event_field.name = "prio";
 	field->event_field.type.atype = atype_integer;
 	field->event_field.type.u.basic.integer.size = sizeof(int) * CHAR_BIT;