[PATCH 10/22] tools lib bpf: Add flags to bpf_create_map()

From: Arnaldo Carvalho de Melo
Date: Tue Dec 13 2016 - 10:12:54 EST


From: Joe Stringer <joe@xxxxxxx>

Commit 6c905981743 ("bpf: pre-allocate hash map elements") introduces
map_flags to bpf_attr for BPF_MAP_CREATE command. Expose this new
parameter in libbpf.

By exposing it, users can access flags such as whether or not to
preallocate the map.

Signed-off-by: Joe Stringer <joe@xxxxxxx>
Acked-by: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20161209024620.31660-4-joe@xxxxxxx
[ Added clarifying comment made by Wang Nan ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/lib/bpf/bpf.c | 3 ++-
tools/lib/bpf/bpf.h | 2 +-
tools/lib/bpf/libbpf.c | 3 ++-
3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 89e8e8e5b60e..d0afb26c2e0f 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -54,7 +54,7 @@ static int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
}

int bpf_create_map(enum bpf_map_type map_type, int key_size,
- int value_size, int max_entries)
+ int value_size, int max_entries, __u32 map_flags)
{
union bpf_attr attr;

@@ -64,6 +64,7 @@ int bpf_create_map(enum bpf_map_type map_type, int key_size,
attr.key_size = key_size;
attr.value_size = value_size;
attr.max_entries = max_entries;
+ attr.map_flags = map_flags;

return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
}
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 61130170a6ad..7fcdce16fd62 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -24,7 +24,7 @@
#include <linux/bpf.h>

int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
- int max_entries);
+ int max_entries, __u32 map_flags);

/* Recommend log buffer size */
#define BPF_LOG_BUF_SIZE 65536
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 2e974593f3e8..84e6b35da4bd 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -854,7 +854,8 @@ bpf_object__create_maps(struct bpf_object *obj)
*pfd = bpf_create_map(def->type,
def->key_size,
def->value_size,
- def->max_entries);
+ def->max_entries,
+ 0);
if (*pfd < 0) {
size_t j;
int err = *pfd;
--
2.9.3