3 Commits

Author	SHA1	Message	Date
Mathieu Desnoyers	d6aaa23a2b	selftests/rseq: Implement rseq_unqual_scalar_typeof ... Allow defining variables and perform cast with a typeof which removes the volatile and const qualifiers. This prevents declaring a stack variable with a volatile qualifier within a macro, which would generate sub-optimal assembler. This is imported from the "librseq" project. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>	2023-08-08 14:42:01 -06:00
Mathieu Desnoyers	ae31573843	selftests/rseq: x86: Template memory ordering and percpu access mode ... Introduce a rseq-x86-bits.h template header which is internally included to generate the static inline functions covering: - relaxed and release memory ordering, - per-cpu-id and per-mm-cid per-cpu data access. This introduces changes to the rseq.h selftests API which require to update the rseq selftest programs. Similar API/templating changes need to be done for other architectures. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-12-mathieu.desnoyers@efficios.com	2022-12-27 12:52:12 +01:00
Mathieu Desnoyers	b53823fb2e	selftests/rseq: Fix: work-around asm goto compiler bugs ... gcc and clang each have their own compiler bugs with respect to asm goto. Implement a work-around for compiler versions known to have those bugs. gcc prior to 4.8.2 miscompiles asm goto. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 gcc prior to 8.1.0 miscompiles asm goto at O1. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103908 clang prior to version 13.0.1 miscompiles asm goto at O2. https://github.com/llvm/llvm-project/issues/52735 Work around these issues by adding a volatile inline asm with memory clobber in the fallthrough after the asm goto and at each label target. Emit this for all compilers in case other similar issues are found in the future. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20220124171253.22072-14-mathieu.desnoyers@efficios.com	2022-02-02 13:11:37 +01:00