Relax SeqCst ordering in standard library. #122729
Commits on Mar 19, 2024
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SeqCst->Relaxed for proc_macro bridge counter.
Relaxed is enough here.
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SeqCst->{Release,Acquire} for alloc error hook.
SeqCst is unnecessary.
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SeqCst->Relaxed for FIRST_PANIC.
Relaxed is enough to make sure this `swap` results in `true` only once.
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SeqCst->{Release,Acquire} in xous mutex.
No need for SeqCst. Release+Acquire is the right memory ordering for a mutex.
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Use less restricted memory ordering in thread_parking::pthread.
SeqCst is unnecessary here.
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SeqCst->{Release,Acquire} in sys_common::thread_local_key.
SeqCst is unnecessary here.
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SeqCst->{Release,Acquire} for wasm DropLock.
SeqCst is unnecessary. Release+Acquire is the right ordering for a mutex.
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SeqCst->Relaxed in pal::windows::pipe.
Relaxed is enough to ensure fetch_add(1) returns each integer exactly once.
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SeqCst->{Release,Acquire} for xous DropLock.
SeqCst is unnecessary. Release+Acquire is the right ordering for a mutex.
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SeqCst->Relaxed for xous set_nonblocking.
The SeqCst wasn't synchronizing with anything. Relaxed is enough.
Commits on Mar 20, 2024
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Use less restricted memory ordering in xous::thread_local_key.
SeqCst isn't necessary in any of these cases.
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SeqCst->Relaxed in std::net::test.
Relaxed is enough to have fetch_add(1) return each value only once (until it wraps around).
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SeqCst->Relaxed in thread local test.
Relaxed memory ordering is fine because spawn()/join() already provides all the synchronization we need.
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SeqCst->Relaxed in condvar test.
Relaxed is enough here. Synchronization is done by the mutex.