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-rw-r--r--Documentation/tracepoints.txt7
1 files changed, 6 insertions, 1 deletions
diff --git a/Documentation/tracepoints.txt b/Documentation/tracepoints.txt
index 5d354e167494..e8ad47b437f3 100644
--- a/Documentation/tracepoints.txt
+++ b/Documentation/tracepoints.txt
@@ -42,7 +42,7 @@ In include/trace/subsys.h :
#include <linux/tracepoint.h>
-DEFINE_TRACE(subsys_eventname,
+DECLARE_TRACE(subsys_eventname,
TPPTOTO(int firstarg, struct task_struct *p),
TPARGS(firstarg, p));
@@ -50,6 +50,8 @@ In subsys/file.c (where the tracing statement must be added) :
#include <trace/subsys.h>
+DEFINE_TRACE(subsys_eventname);
+
void somefct(void)
{
...
@@ -86,6 +88,9 @@ to limit collisions. Tracepoint names are global to the kernel: they are
considered as being the same whether they are in the core kernel image or in
modules.
+If the tracepoint has to be used in kernel modules, an
+EXPORT_TRACEPOINT_SYMBOL_GPL() or EXPORT_TRACEPOINT_SYMBOL() can be used to
+export the defined tracepoints.
* Probe / tracepoint example
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