3 files changed, 12 insertions, 0 deletions

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index d41394a1af3..8a73f75beb1 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1321,6 +1321,8 @@ extern int perf_output_begin(struct perf_output_handle *handle,
 extern void perf_output_end(struct perf_output_handle *handle);
 extern unsigned int perf_output_copy(struct perf_output_handle *handle,
                              const void *buf, unsigned int len);
+extern unsigned int perf_output_skip(struct perf_output_handle *handle,
+                                     unsigned int len);
 extern int perf_swevent_get_recursion_context(void);
 extern void perf_swevent_put_recursion_context(int rctx);
 extern void perf_event_enable(struct perf_event *event);
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index 7fd5408493d..ce7bdfc1d04 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -114,6 +114,10 @@ static inline int memcpy_common(void *dst, const void *src, size_t n)
 
 DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
 
+#define MEMCPY_SKIP(dst, src, n) (n)
+
+DEFINE_OUTPUT_COPY(__output_skip, MEMCPY_SKIP)
+
 #ifndef arch_perf_out_copy_user
 #define arch_perf_out_copy_user __copy_from_user_inatomic
 #endif
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index b4c2ad3dee7..23cb34ff397 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -188,6 +188,12 @@ unsigned int perf_output_copy(struct perf_output_handle *handle,
         return __output_copy(handle, buf, len);
 }
 
+unsigned int perf_output_skip(struct perf_output_handle *handle,
+                              unsigned int len)
+{
+        return __output_skip(handle, NULL, len);
+}
+
 void perf_output_end(struct perf_output_handle *handle)
 {
         perf_output_put_handle(handle);