libbpf is used as a submodule in bcc.
When importing latest libbpf repo in bcc, I observed the
following compilation errors when compiling on ubuntu 16.04.
.../netlink.c:416:23: error: ‘TC_H_CLSACT’ undeclared (first use in
this function)
*parent = TC_H_MAKE(TC_H_CLSACT,
^
.../netlink.c:418:9: error: ‘TC_H_MIN_INGRESS’ undeclared (first
use in this function)
TC_H_MIN_INGRESS : TC_H_MIN_EGRESS);
^
.../netlink.c:418:28: error: ‘TC_H_MIN_EGRESS’ undeclared (first
use in this function)
TC_H_MIN_INGRESS : TC_H_MIN_EGRESS);
^
.../netlink.c: In function ‘__get_tc_info’:
.../netlink.c:522:11: error: ‘TCA_BPF_ID’ undeclared (first use in
this function)
if (!tbb[TCA_BPF_ID])
^
In ubuntu 16.04, TCA_BPF_* enumerator looks like below
enum {
TCA_BPF_UNSPEC,
TCA_BPF_ACT,
...
TCA_BPF_NAME,
TCA_BPF_FLAGS,
__TCA_BPF_MAX,
};
#define TCA_BPF_MAX (__TCA_BPF_MAX - 1)
while in latest bpf-next, the enumerator looks like
enum {
TCA_BPF_UNSPEC,
...
TCA_BPF_FLAGS,
TCA_BPF_FLAGS_GEN,
TCA_BPF_TAG,
TCA_BPF_ID,
__TCA_BPF_MAX,
};
In this patch, TCA_BPF_ID is defined as a macro with proper value and
this
works regardless of whether TCA_BPF_ID is defined in uapi header or not.
TCA_BPF_MAX is also adjusted in a similar way.
Fixes: 715c5ce454a6 ("libbpf: Add low level TC-BPF management API")
Cc: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Signed-off-by: Yonghong Song <yhs@xxxxxx>
---
tools/lib/bpf/netlink.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
Changelog:
v2 -> v3:
- define/redefine TCA_BPF_MAX based on latest uapi header.
this enables to remove the v2 check "TCA_BPF_MAX < TCA_BPF_ID"
in __get_tc_info() which may cause -EOPNOTSUPP error
if the library is compiled in old system and used in
newer system.
v1 -> v2:
- gcc 8.3 doesn't like macro condition
(__TCA_BPF_MAX - 1) <= 10
where __TCA_BPF_MAX is an enumerator value.
So define TCA_BPF_ID macro without macro condition.
diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c
index 39f25e09b51e..37cb6b50f4b3 100644
--- a/tools/lib/bpf/netlink.c
+++ b/tools/lib/bpf/netlink.c
@@ -22,6 +22,29 @@
#define SOL_NETLINK 270
#endif
+#ifndef TC_H_CLSACT
+#define TC_H_CLSACT TC_H_INGRESS
+#endif
+
+#ifndef TC_H_MIN_INGRESS
+#define TC_H_MIN_INGRESS 0xFFF2U
+#endif
+
+#ifndef TC_H_MIN_EGRESS
+#define TC_H_MIN_EGRESS 0xFFF3U
+#endif
+
+/* TCA_BPF_ID is an enumerator value in uapi/linux/pkt_cls.h.
+ * Declare it as a macro here so old system can still work
+ * without TCA_BPF_ID defined in pkt_cls.h.
+ */
+#define TCA_BPF_ID 11
+
+#ifdef TCA_BPF_MAX
+#undef TCA_BPF_MAX
+#endif
+#define TCA_BPF_MAX 11
+
typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct
nlattr **tb);
typedef int (*__dump_nlmsg_t)(struct nlmsghdr *nlmsg,
libbpf_dump_nlmsg_t,
