| Message ID | 20210118091753.107572-1-bjorn.topel@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [bpf-next] samples/bpf: add BPF_ATOMIC_OP macro for BPF samples | expand |
On 2021-01-18 11:57, Brendan Jackman wrote: > I actually deliberately skipped this file, thinking that people were > unlikely to want to add assembly-based atomics code under samples/ > > I guess it's nice for people to be able to e.g. move/copy code from > the selftests. > Yes, that, and the fact that one sample broke w/o the BPF_ATOMIC_OP. > On Mon, 18 Jan 2021 at 10:18, Björn Töpel <bjorn.topel@gmail.com> wrote: >> >> From: Björn Töpel <bjorn.topel@intel.com> >> >> Brendan Jackman added extend atomic operations to the BPF instruction >> set in commit 7064a7341a0d ("Merge branch 'Atomics for eBPF'"), which >> introduces the BPF_ATOMIC_OP macro. However, that macro was missing >> for the BPF samples. Fix that by adding it into bpf_insn.h. >> >> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> > > Reviewed-by: Brendan Jackman <jackmanb@google.com> > Thanks! Björn
Hello: This patch was applied to bpf/bpf-next.git (refs/heads/master): On Mon, 18 Jan 2021 10:17:53 +0100 you wrote: > From: Björn Töpel <bjorn.topel@intel.com> > > Brendan Jackman added extend atomic operations to the BPF instruction > set in commit 7064a7341a0d ("Merge branch 'Atomics for eBPF'"), which > introduces the BPF_ATOMIC_OP macro. However, that macro was missing > for the BPF samples. Fix that by adding it into bpf_insn.h. > > [...] Here is the summary with links: - [bpf-next] samples/bpf: add BPF_ATOMIC_OP macro for BPF samples https://git.kernel.org/bpf/bpf-next/c/af6953b633b3 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/samples/bpf/bpf_insn.h b/samples/bpf/bpf_insn.h index db67a2847395..aee04534483a 100644 --- a/samples/bpf/bpf_insn.h +++ b/samples/bpf/bpf_insn.h @@ -134,15 +134,31 @@ struct bpf_insn; .off = OFF, \ .imm = 0 }) -/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */ - -#define BPF_STX_XADD(SIZE, DST, SRC, OFF) \ +/* + * Atomic operations: + * + * BPF_ADD *(uint *) (dst_reg + off16) += src_reg + * BPF_AND *(uint *) (dst_reg + off16) &= src_reg + * BPF_OR *(uint *) (dst_reg + off16) |= src_reg + * BPF_XOR *(uint *) (dst_reg + off16) ^= src_reg + * BPF_ADD | BPF_FETCH src_reg = atomic_fetch_add(dst_reg + off16, src_reg); + * BPF_AND | BPF_FETCH src_reg = atomic_fetch_and(dst_reg + off16, src_reg); + * BPF_OR | BPF_FETCH src_reg = atomic_fetch_or(dst_reg + off16, src_reg); + * BPF_XOR | BPF_FETCH src_reg = atomic_fetch_xor(dst_reg + off16, src_reg); + * BPF_XCHG src_reg = atomic_xchg(dst_reg + off16, src_reg) + * BPF_CMPXCHG r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg) + */ + +#define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \ ((struct bpf_insn) { \ .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \ .dst_reg = DST, \ .src_reg = SRC, \ .off = OFF, \ - .imm = BPF_ADD }) + .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 */