From: Yonghong Song Date: Tue, 2 Apr 2024 02:54:46 +0000 (-0700) Subject: selftests/bpf: Using llvm may_goto inline asm for cond_break macro X-Git-Tag: net-accept-more-20240515~4^2~102^2~66 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=965c6167c93f3fac53e25807f83c07e87b3c085a;p=linux-block.git selftests/bpf: Using llvm may_goto inline asm for cond_break macro Currently, cond_break macro uses bytes to encode the may_goto insn. Patch [1] in llvm implemented may_goto insn in BPF backend. Replace byte-level encoding with llvm inline asm for better usability. Using llvm may_goto insn is controlled by macro __BPF_FEATURE_MAY_GOTO. [1] https://github.com/llvm/llvm-project/commit/0e0bfacff71859d1f9212205f8f873d47029d3fb Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20240402025446.3215182-1-yonghong.song@linux.dev --- diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h index a5b9df38c162..3329ea080865 100644 --- a/tools/testing/selftests/bpf/bpf_experimental.h +++ b/tools/testing/selftests/bpf/bpf_experimental.h @@ -326,6 +326,16 @@ l_true: \ }) #endif +#ifdef __BPF_FEATURE_MAY_GOTO +#define cond_break \ + ({ __label__ l_break, l_continue; \ + asm volatile goto("may_goto %l[l_break]" \ + :::: l_break); \ + goto l_continue; \ + l_break: break; \ + l_continue:; \ + }) +#else #define cond_break \ ({ __label__ l_break, l_continue; \ asm volatile goto("1:.byte 0xe5; \ @@ -337,6 +347,7 @@ l_true: \ l_break: break; \ l_continue:; \ }) +#endif #ifndef bpf_nop_mov #define bpf_nop_mov(var) \