riscv/musl - musl - Gitea: Git with a cup of tea

History

Rich Felker 1281779330 fix broken atomic store on powerpc[64] in our memory model, all atomics are supposed to be full barriers; stores are not release-only. this is important because store is used as an unlock operation in places where it needs to acquire the waiter count to determine if a futex wake is needed. at least in the malloc-internal locks, but possibly elsewhere, soft deadlocks from missing futex wake (breakable by poking the threads to restart the syscall, e.g. by attaching a tracer) were reported to occur. once the malloc lock is replaced with Jens Gustedt's new lock implementation (see commit `47d0bcd476`), malloc will not be affected by the issue, but it's not clear that other uses won't be. reducing the strength of the ordering properties required from a_store would require a thorough analysis of how it's used. to fix the problem, I'm removing the powerpc[64]-specific a_store definition; now, the top-level atomic.h will implement a_store using a_barrier on both sides of the store. it's not clear to me yet whether there might be issues with the other atomics. it's possible that a_post_llsc needs to be replaced with a full barrier to guarantee the formal semanics we want, but either way I think the difference is unlikely to impact the way we use them.		8 years ago
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bits	add support for arch-specific ptrace command macros	8 years ago
atomic_arch.h	fix broken atomic store on powerpc[64]	8 years ago
crt_arch.h	add powerpc64 port	10 years ago
pthread_arch.h	fix TLS layout of TLS variant I when there is a gap above TP	8 years ago
reloc.h	fix ld-behavior-dependent crash in ppc64 ldso startup	9 years ago
syscall_arch.h	add powerpc64 port	10 years ago