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Use *NSYNC for POSIX threads locking APIs

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Condition variables, barriers, and r/w locks now work very well.
This commit is contained in:
Justine Tunney 2022-09-11 11:02:07 -07:00
parent 3de35e196c
commit b5cb71ab84
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GPG key ID: BE714B4575D6E328
197 changed files with 3734 additions and 3817 deletions
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113
third_party/nsync/atomic.internal.h vendored Normal file
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#ifndef NSYNC_ATOMIC_INTERNAL_H_
#define NSYNC_ATOMIC_INTERNAL_H_
#include "libc/intrin/atomic.h"
#include "third_party/nsync/atomic.h"
#if !(__ASSEMBLER__ + __LINKER__ + 0)
COSMOPOLITAN_C_START_
/* Atomic operations on nsync_atomic_uint32_ quantities
CAS, load, and store.
Normally, these are used only on nsync_atomic_uint32_ values, but on
Linux they may be invoked on int values, because futexes operate on
int values. A compile-time check in the futex code ensures that both
int and nsync_atomic_uint32_ are 32 bits.
Memory barriers:
Operations with the suffixes _ACQ and _RELACQ ensure that the
operation appears to complete before other memory operations
subsequently performed by the same thread, as seen by other
threads. (In the case of ATM_CAS_ACQ, this applies only if
the operation returns a non-zero value.)
Operations with the suffixes _REL and _RELACQ ensure that the
operation appears to complete after other memory operations
previously performed by the same thread, as seen by other
threads. (In the case of ATM_CAS_REL, this applies only if
the operation returns a non-zero value.)
// Atomically,
// int ATM_CAS (nsync_atomic_uint32_ *p,
// uint32_t old_value, uint32_t new_value) {
// if (*p == old_value) {
// *p = new_value;
// return (some-non-zero-value);
// } else {
// return (0);
// }
// }
// *_ACQ, *_REL, *_RELACQ variants are available,
// with the barrier semantics described above.
int ATM_CAS (nsync_atomic_uint32_ *p, uint32_t old_value,
uint32_t new_value);
// Atomically,
// uint32_t ATM_LOAD (nsync_atomic_uint32_ *p) { return (*p); }
// A *_ACQ variant is available,
// with the barrier semantics described above.
uint32_t ATM_LOAD (nsync_atomic_uint32_ *p);
// Atomically,
// void ATM_STORE (nsync_atomic_uint32_ *p, uint32_t value) {
// *p = value;
// }
// A *_REL variant is available,
// with the barrier semantics described above.
void ATM_STORE (nsync_atomic_uint32_ *p, uint32_t value);
*/
static inline int atm_cas_nomb_u32_(nsync_atomic_uint32_ *p, uint32_t o,
uint32_t n) {
return atomic_compare_exchange_strong_explicit(NSYNC_ATOMIC_UINT32_PTR_(p),
&o, n, memory_order_relaxed,
memory_order_relaxed);
}
static inline int atm_cas_acq_u32_(nsync_atomic_uint32_ *p, uint32_t o,
uint32_t n) {
return atomic_compare_exchange_strong_explicit(NSYNC_ATOMIC_UINT32_PTR_(p),
&o, n, memory_order_acquire,
memory_order_relaxed);
}
static inline int atm_cas_rel_u32_(nsync_atomic_uint32_ *p, uint32_t o,
uint32_t n) {
return atomic_compare_exchange_strong_explicit(NSYNC_ATOMIC_UINT32_PTR_(p),
&o, n, memory_order_release,
memory_order_relaxed);
}
static inline int atm_cas_relacq_u32_(nsync_atomic_uint32_ *p, uint32_t o,
uint32_t n) {
return atomic_compare_exchange_strong_explicit(NSYNC_ATOMIC_UINT32_PTR_(p),
&o, n, memory_order_acq_rel,
memory_order_relaxed);
}
#define ATM_CAS_HELPER_(barrier, p, o, n) \
(atm_cas_##barrier##_u32_((p), (o), (n)))
#define ATM_CAS(p, o, n) ATM_CAS_HELPER_(nomb, (p), (o), (n))
#define ATM_CAS_ACQ(p, o, n) ATM_CAS_HELPER_(acq, (p), (o), (n))
#define ATM_CAS_REL(p, o, n) ATM_CAS_HELPER_(rel, (p), (o), (n))
#define ATM_CAS_RELACQ(p, o, n) ATM_CAS_HELPER_(relacq, (p), (o), (n))
/* Need a cast to remove "const" from some uses. */
#define ATM_LOAD(p) \
(atomic_load_explicit((nsync_atomic_uint32_ *)NSYNC_ATOMIC_UINT32_PTR_(p), \
memory_order_relaxed))
#define ATM_LOAD_ACQ(p) \
(atomic_load_explicit((nsync_atomic_uint32_ *)NSYNC_ATOMIC_UINT32_PTR_(p), \
memory_order_acquire))
#define ATM_STORE(p, v) \
(atomic_store_explicit(NSYNC_ATOMIC_UINT32_PTR_(p), (v), \
memory_order_relaxed))
#define ATM_STORE_REL(p, v) \
(atomic_store_explicit(NSYNC_ATOMIC_UINT32_PTR_(p), (v), \
memory_order_release))
COSMOPOLITAN_C_END_
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* NSYNC_ATOMIC_INTERNAL_H_ */