diff options
| author | Brendan Jackman <jackmanb@google.com> | 2021-01-14 18:17:44 +0000 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2021-01-14 18:34:29 -0800 |
| commit | 91c960b0056672e74627776655c926388350fa30 (patch) | |
| tree | b15d68c17ead28b128791f8e710d9efa2a711267 /tools/include/linux | |
| parent | e5f02caccfae94f5baf6ec6dbb57ce8a7e9a40e7 (diff) | |
bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
A subsequent patch will add additional atomic operations. These new
operations will use the same opcode field as the existing XADD, with
the immediate discriminating different operations.
In preparation, rename the instruction mode BPF_ATOMIC and start
calling the zero immediate BPF_ADD.
This is possible (doesn't break existing valid BPF progs) because the
immediate field is currently reserved MBZ and BPF_ADD is zero.
All uses are removed from the tree but the BPF_XADD definition is
kept around to avoid breaking builds for people including kernel
headers.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
Diffstat (limited to 'tools/include/linux')
| -rw-r--r-- | tools/include/linux/filter.h | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/tools/include/linux/filter.h b/tools/include/linux/filter.h index ca28b6ab8db7..e870c9039f0d 100644 --- a/tools/include/linux/filter.h +++ b/tools/include/linux/filter.h @@ -169,15 +169,22 @@ .off = OFF, \ .imm = 0 }) -/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */ +/* + * Atomic operations: + * + * BPF_ADD *(uint *) (dst_reg + off16) += src_reg + */ -#define BPF_STX_XADD(SIZE, DST, SRC, OFF) \ +#define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \ ((struct bpf_insn) { \ - .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \ + .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \ .dst_reg = DST, \ .src_reg = SRC, \ .off = OFF, \ - .imm = 0 }) + .imm = OP }) + +/* Legacy alias */ +#define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF) /* Memory store, *(uint *) (dst_reg + off16) = imm32 */ |