diff --git a/tools/testing/selftests/bpf/progs/pyperf.h b/tools/testing/selftests/bpf/progs/pyperf.h index 2fb7adafb6b64..54c9845c953f6 100644 --- a/tools/testing/selftests/bpf/progs/pyperf.h +++ b/tools/testing/selftests/bpf/progs/pyperf.h @@ -231,8 +231,12 @@ int __on_event(struct bpf_raw_tracepoint_args *ctx) #ifdef NO_UNROLL #pragma clang loop unroll(disable) #else +#ifdef UNROLL_COUNT +#pragma clang loop unroll_count(UNROLL_COUNT) +#else #pragma clang loop unroll(full) #endif +#endif /* NO_UNROLL */ /* Unwind python stack */ for (int i = 0; i < STACK_MAX_LEN; ++i) { if (frame_ptr && get_frame_data(frame_ptr, pidData, &frame, &sym)) { diff --git a/tools/testing/selftests/bpf/progs/pyperf180.c b/tools/testing/selftests/bpf/progs/pyperf180.c index c39f559d3100e..42c4a8b62e360 100644 --- a/tools/testing/selftests/bpf/progs/pyperf180.c +++ b/tools/testing/selftests/bpf/progs/pyperf180.c @@ -1,4 +1,26 @@ // SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2019 Facebook #define STACK_MAX_LEN 180 + +/* llvm upstream commit at clang18 + * https://github.com/llvm/llvm-project/commit/1a2e77cf9e11dbf56b5720c607313a566eebb16e + * changed inlining behavior and caused compilation failure as some branch + * target distance exceeded 16bit representation which is the maximum for + * cpu v1/v2/v3. Macro __BPF_CPU_VERSION__ is later implemented in clang18 + * to specify which cpu version is used for compilation. So a smaller + * unroll_count can be set if __BPF_CPU_VERSION__ is less than 4, which + * reduced some branch target distances and resolved the compilation failure. + * + * To capture the case where a developer/ci uses clang18 but the corresponding + * repo checkpoint does not have __BPF_CPU_VERSION__, a smaller unroll_count + * will be set as well to prevent potential compilation failures. + */ +#ifdef __BPF_CPU_VERSION__ +#if __BPF_CPU_VERSION__ < 4 +#define UNROLL_COUNT 90 +#endif +#elif __clang_major__ == 18 +#define UNROLL_COUNT 90 +#endif + #include "pyperf.h" diff --git a/tools/testing/selftests/bpf/progs/pyperf600.c b/tools/testing/selftests/bpf/progs/pyperf600.c index cb49b89e37cd4..ce1aa5189cc49 100644 --- a/tools/testing/selftests/bpf/progs/pyperf600.c +++ b/tools/testing/selftests/bpf/progs/pyperf600.c @@ -1,9 +1,12 @@ // SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2019 Facebook #define STACK_MAX_LEN 600 -/* clang will not unroll the loop 600 times. - * Instead it will unroll it to the amount it deemed - * appropriate, but the loop will still execute 600 times. - * Total program size is around 90k insns +/* Full unroll of 600 iterations will have total + * program size close to 298k insns and this may + * cause BPF_JMP insn out of 16-bit integer range. + * So limit the unroll size to 150 so the + * total program size is around 80k insns but + * the loop will still execute 600 times. */ +#define UNROLL_COUNT 150 #include "pyperf.h"