kernel_optimize_test/kernel/bpf
Martin KaFai Lau 23127b33ec bpf: Create a new btf_name_by_offset() for non type name use case
The current btf_name_by_offset() is returning "(anon)" type name for
the offset == 0 case and "(invalid-name-offset)" for the out-of-bound
offset case.

It fits well for the internal BTF verbose log purpose which
is focusing on type.  For example,
offset == 0 => "(anon)" => anonymous type/name.
Returning non-NULL for the bad offset case is needed
during the BTF verification process because the BTF verifier may
complain about another field first before discovering the name_off
is invalid.

However, it may not be ideal for the newer use case which does not
necessary mean type name.  For example, when logging line_info
in the BPF verifier in the next patch, it is better to log an
empty src line instead of logging "(anon)".

The existing bpf_name_by_offset() is renamed to __bpf_name_by_offset()
and static to btf.c.

A new bpf_name_by_offset() is added for generic context usage.  It
returns "\0" for name_off == 0 (note that btf->strings[0] is "\0")
and NULL for invalid offset.  It allows the caller to decide
what is the best output in its context.

The new btf_name_by_offset() is overlapped with btf_name_offset_valid().
Hence, btf_name_offset_valid() is removed from btf.h to keep the btf.h API
minimal.  The existing btf_name_offset_valid() usage in btf.c could also be
replaced later.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-12-14 14:17:34 -08:00
..
arraymap.c bpf: pass struct btf pointer to the map_check_btf() callback 2018-12-12 15:33:33 -08:00
bpf_lru_list.c
bpf_lru_list.h
btf.c bpf: Create a new btf_name_by_offset() for non type name use case 2018-12-14 14:17:34 -08:00
cgroup.c bpf: add cg_skb_is_valid_access for BPF_PROG_TYPE_CGROUP_SKB 2018-10-19 13:49:34 -07:00
core.c bpf: Add bpf_line_info support 2018-12-09 13:54:38 -08:00
cpumap.c
devmap.c bpf: devmap: fix wrong interface selection in notifier_call 2018-10-26 00:32:21 +02:00
disasm.c
disasm.h
hashtab.c bpf: allow zero-initializing hash map seed 2018-11-20 00:53:39 +01:00
helpers.c bpf: fix direct packet write into pop/peek helpers 2018-10-25 17:02:06 -07:00
inode.c
local_storage.c bpf: add bpffs pretty print for cgroup local storage maps 2018-12-12 15:33:38 -08:00
lpm_trie.c bpf: pass struct btf pointer to the map_check_btf() callback 2018-12-12 15:33:33 -08:00
Makefile bpf: add queue and stack maps 2018-10-19 13:24:31 -07:00
map_in_map.c bpf: don't allow create maps of per-cpu cgroup local storages 2018-10-01 16:18:33 +02:00
map_in_map.h
offload.c bpf: fix null pointer dereference on pointer offload 2018-11-16 20:48:27 -08:00
percpu_freelist.c
percpu_freelist.h
queue_stack_maps.c bpf: fix integer overflow in queue_stack_map 2018-11-22 21:29:40 +01:00
reuseport_array.c
stackmap.c bpf: rename stack trace map operations 2018-10-19 13:24:30 -07:00
syscall.c bpf: remove obsolete prog->aux sanitation in bpf_insn_prepare_dump 2018-12-13 12:42:44 -08:00
tnum.c
verifier.c bpf: Create a new btf_name_by_offset() for non type name use case 2018-12-14 14:17:34 -08:00
xskmap.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-19 11:03:06 -07:00