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 d96dc88d3b04067135fe80c95628fca37a29c022..73c35714226842b248027b214989e56570e4378f 100644 (file)
--- 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) );})