selftests/bpf: Use asm constraint "m" for LoongArch

2024-12-27T13:02:17Z

commit 29d44cce324dab2bd86c447071a596262e7109b6 upstream. Currently, LoongArch LLVM does not support the constraint "o" and no plan to support it, it only supports the similar constraint "m", so change the constraints from "nor" in the "else" case to arch-specific "nmr" to avoid the build error such as "unexpected asm memory constraint" for LoongArch. Fixes: 630301b0d59d ("selftests/bpf: Add basic USDT selftests") Suggested-by: Weining Lu Suggested-by: Li Chen Signed-off-by: Tiezhu Yang Signed-off-by: Daniel Borkmann Reviewed-by: Huacai Chen Cc: stable@vger.kernel.org Link: https://llvm.org/docs/LangRef.html#supported-constraint-code-list Link: https://github.com/llvm/llvm-project/blob/main/llvm/lib/Target/LoongArch/LoongArchISelDAGToDAG.cpp#L172 Link: https://lore.kernel.org/bpf/20241219111506.20643-1-yangtiezhu@loongson.cn Signed-off-by: Greg Kroah-Hartman

selftests/bpf: Add basic USDT selftests

2022-04-05T20:16:08Z

Add semaphore-based USDT to test_progs itself and write basic tests to valicate both auto-attachment and manual attachment logic, as well as BPF-side functionality. Also add subtests to validate that libbpf properly deduplicates USDT specs and handles spec overflow situations correctly, as well as proper "rollback" of partially-attached multi-spec USDT. BPF-side of selftest intentionally consists of two files to validate that usdt.bpf.h header can be included from multiple source code files that are subsequently linked into final BPF object file without causing any symbol duplication or other issues. We are validating that __weak maps and bpf_usdt_xxx() API functions defined in usdt.bpf.h do work as intended. USDT selftests utilize sys/sdt.h header that on Ubuntu systems comes from systemtap-sdt-devel package. But to simplify everyone's life, including CI but especially casual contributors to bpf/bpf-next that are trying to build selftests, I've checked in sys/sdt.h header from [0] directly. This way it will work on all architectures and distros without having to figure it out for every relevant combination and adding any extra implicit package dependencies. [0] https://sourceware.org/git?p=systemtap.git;a=blob_plain;f=includes/sys/sdt.h;h=ca0162b4dc57520b96638c8ae79ad547eb1dd3a1;hb=HEAD Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Reviewed-by: Alan Maguire Acked-by: Dave Marchevsky Link: https://lore.kernel.org/bpf/20220404234202.331384-7-andrii@kernel.org

kernel/tools/testing/selftests/bpf/sdt.h, branch linux-rolling-stable

selftests/bpf: Use asm constraint "m" for LoongArch

selftests/bpf: Add basic USDT selftests