diff mbox series

[bpf-next,2/7] libbpf: Open code low level bpf commands.

Message ID 20220131220528.98088-3-alexei.starovoitov@gmail.com (mailing list archive)
State Accepted
Commit e981f41fd029d37b3e1c8aad2d72d3fe57a104d6
Delegated to: BPF
Headers show
Series bpf: drop libbpf from bpf preload. | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 7 maintainers not CCed: kpsingh@kernel.org john.fastabend@gmail.com kafai@fb.com songliubraving@fb.com ast@kernel.org yhs@fb.com netdev@vger.kernel.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch warning CHECK: No space is necessary after a cast WARNING: line length of 90 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next success VM_Test

Commit Message

Alexei Starovoitov Jan. 31, 2022, 10:05 p.m. UTC 
From: Alexei Starovoitov <ast@kernel.org>

Open code low level bpf commands used by light skeleton to
be able to avoid full libbpf eventually.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 tools/lib/bpf/skel_internal.h | 44 +++++++++++++++++++++++++++++++++--
 1 file changed, 42 insertions(+), 2 deletions(-)

Comments

Martin KaFai Lau Feb. 1, 2022, 6:52 p.m. UTC | #1 
On Mon, Jan 31, 2022 at 02:05:23PM -0800, Alexei Starovoitov wrote:
> From: Alexei Starovoitov <ast@kernel.org>
> 
> Open code low level bpf commands used by light skeleton to
> be able to avoid full libbpf eventually.
Acked-by: Martin KaFai Lau <kafai@fb.com>
diff mbox series

Patch

diff --git a/tools/lib/bpf/skel_internal.h b/tools/lib/bpf/skel_internal.h
index 0b84d8e6b72a..57507f1c1934 100644
--- a/tools/lib/bpf/skel_internal.h
+++ b/tools/lib/bpf/skel_internal.h
@@ -70,19 +70,59 @@  static inline int skel_closenz(int fd)
 	return -EINVAL;
 }
 
+#ifndef offsetofend
+#define offsetofend(TYPE, MEMBER) \
+	(offsetof(TYPE, MEMBER)	+ sizeof((((TYPE *)0)->MEMBER)))
+#endif
+
+static inline int skel_map_create(enum bpf_map_type map_type,
+				  const char *map_name,
+				  __u32 key_size,
+				  __u32 value_size,
+				  __u32 max_entries)
+{
+	const size_t attr_sz = offsetofend(union bpf_attr, map_extra);
+	union bpf_attr attr;
+
+	memset(&attr, 0, attr_sz);
+
+	attr.map_type = map_type;
+	strncpy(attr.map_name, map_name, sizeof(attr.map_name));
+	attr.key_size = key_size;
+	attr.value_size = value_size;
+	attr.max_entries = max_entries;
+
+	return skel_sys_bpf(BPF_MAP_CREATE, &attr, attr_sz);
+}
+
+static inline int skel_map_update_elem(int fd, const void *key,
+				       const void *value, __u64 flags)
+{
+	const size_t attr_sz = offsetofend(union bpf_attr, flags);
+	union bpf_attr attr;
+
+	memset(&attr, 0, attr_sz);
+	attr.map_fd = fd;
+	attr.key = (long) key;
+	attr.value = (long) value;
+	attr.flags = flags;
+
+	return skel_sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, attr_sz);
+}
+
 static inline int bpf_load_and_run(struct bpf_load_and_run_opts *opts)
 {
 	int map_fd = -1, prog_fd = -1, key = 0, err;
 	union bpf_attr attr;
 
-	map_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "__loader.map", 4, opts->data_sz, 1, NULL);
+	map_fd = skel_map_create(BPF_MAP_TYPE_ARRAY, "__loader.map", 4, opts->data_sz, 1);
 	if (map_fd < 0) {
 		opts->errstr = "failed to create loader map";
 		err = -errno;
 		goto out;
 	}
 
-	err = bpf_map_update_elem(map_fd, &key, opts->data, 0);
+	err = skel_map_update_elem(map_fd, &key, opts->data, 0);
 	if (err < 0) {
 		opts->errstr = "failed to update loader map";
 		err = -errno;