From 0c178e9debc8f0a305149f5ccace6796f6931a1d Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 24 Feb 2026 11:39:13 +0100 Subject: selftests/bpf: Emit nop,nop5 instructions combo for x86_64 arch Syncing latest usdt.h change [1]. Now that we have nop5 optimization support in kernel, let's emit nop,nop5 for usdt probe. We leave it up to the library to use desirable nop instruction. [1] https://github.com/libbpf/usdt/commit/c9865d158984fb2b73e3cbbdcdfb4f583ad36a73 Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20260224103915.1369690-4-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/usdt.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/bpf/usdt.h b/tools/testing/selftests/bpf/usdt.h index 549d1f774810..c71e21df38b3 100644 --- a/tools/testing/selftests/bpf/usdt.h +++ b/tools/testing/selftests/bpf/usdt.h @@ -312,6 +312,8 @@ struct usdt_sema { volatile unsigned short active; }; #ifndef USDT_NOP #if defined(__ia64__) || defined(__s390__) || defined(__s390x__) #define USDT_NOP nop 0 +#elif defined(__x86_64__) +#define USDT_NOP .byte 0x90, 0x0f, 0x1f, 0x44, 0x00, 0x0 /* nop, nop5 */ #else #define USDT_NOP nop #endif -- cgit v1.2.3