samples/bpf: check before defining offsetof
Fixes the following warning
samples/bpf/test_lru_dist.c:28:0: warning: "offsetof" redefined
#define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER)
In file included from ./tools/lib/bpf/bpf.h:25:0,
from samples/bpf/libbpf.h:5,
from samples/bpf/test_lru_dist.c:24:
/usr/lib/gcc/x86_64-redhat-linux/6.3.1/include/stddef.h:417:0: note: this is the location of the previous definition
#define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER)
Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/samples/bpf/test_lru_dist.c b/samples/bpf/test_lru_dist.c
index d96dc88..73c3571 100644
--- a/samples/bpf/test_lru_dist.c
+++ b/samples/bpf/test_lru_dist.c
@@ -25,7 +25,9 @@
#include "bpf_util.h"
#define min(a, b) ((a) < (b) ? (a) : (b))
-#define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER)
+#ifndef offsetof
+# define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER)
+#endif
#define container_of(ptr, type, member) ({ \
const typeof( ((type *)0)->member ) *__mptr = (ptr); \
(type *)( (char *)__mptr - offsetof(type,member) );})