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Make mutex calling code 10x tinier

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Calls to lock/unlock functions are now NOPs by default. The first time
clone() is called, they get turned into CALL instructions. Doing this
caused funcctions like fputc() to shrink from 85 bytes to 45+4 bytes.
Since the ANSI solution of `(__threaded && lock())` inlines os much
superfluous binary content into functions all over the place.
This commit is contained in:
Justine Tunney 2022-06-12 19:33:42 -07:00
parent 8cdec62f5b
commit 8b72490431
32 changed files with 494 additions and 210 deletions
Download patch file Download diff file Expand all files Collapse all files

71
libc/intrin/spinlock.h
View file

@ -3,67 +3,40 @@
/*───────────────────────────────────────────────────────────────────────────│─╗
│ cosmopolitan § spinlocks ─╬─│┼
╚────────────────────────────────────────────────────────────────────────────│─╝
privileged unsophisticated locking subroutines */
fast tiny inline synchronization routines */
#if defined(MODE_DBG) && !defined(_SPINLOCK_DEBUG)
#define _SPINLOCK_DEBUG
#endif
#if defined(_SPINLOCK_DEBUG)
#define _spinlock(lock) _spinlock_ndebug(lock)
#define _spinlock_ndebug(lock) _spinlock_cooperative(lock)
#define _trylock(lock) _trylock_debug(lock)
#define _seizelock(lock) _seizelock_impl(lock, _spinlock_gettid())
#elif defined(TINY)
#define _spinlock(lock) _spinlock_tiny(lock)
#define _spinlock_ndebug(lock) _spinlock_tiny(lock)
#define _trylock(lock) _trylock_inline(lock)
#define _seizelock(lock) _seizelock_impl(lock, 1)
#ifdef TINY
#define _spinlock(lock) _spinlock_tiny(lock)
#else
#define _spinlock(lock) _spinlock_cooperative(lock)
#define _spinlock_ndebug(lock) _spinlock_cooperative(lock)
#define _trylock(lock) _trylock_inline(lock)
#define _seizelock(lock) _seizelock_impl(lock, 1)
#define _spinlock(lock) _spinlock_cooperative(lock)
#endif
#define _trylock_inline(lock) __atomic_test_and_set(lock, __ATOMIC_SEQ_CST)
#define _spunlock(lock) __atomic_store_n(lock, 0, __ATOMIC_RELAXED)
#define _trylock_debug(lock) \
_trylock_debug_4(lock, #lock, __FILE__, __LINE__, __FUNCTION__)
#define _spinlock_debug(lock) \
_spinlock_debug_4(lock, #lock, __FILE__, __LINE__, __FUNCTION__)
#define _spunlock(lock) \
do { \
autotype(lock) __lock = (lock); \
typeof(*__lock) __x = 0; \
__atomic_store(__lock, &__x, __ATOMIC_RELAXED); \
} while (0)
#define _seizelock_impl(lock, value) \
do { \
#define _seizelock(lock, value) \
({ \
autotype(lock) __lock = (lock); \
typeof(*__lock) __x = (value); \
__atomic_store(__lock, &__x, __ATOMIC_RELEASE); \
} while (0)
})
#define _spinlock_tiny(lock) \
do { \
autotype(lock) __lock = (lock); \
while (_trylock_inline(__lock)) { \
__builtin_ia32_pause(); \
} \
} while (0)
#define _spinlock_tiny(lock) \
({ \
autotype(lock) __lock = (lock); \
while (_trylock(__lock)) { \
__builtin_ia32_pause(); \
} \
0; \
})
#define _spinlock_cooperative(lock) \
do { \
({ \
autotype(lock) __lock = (lock); \
typeof(*__lock) __x; \
unsigned __tries = 0; \
for (;;) { \
__atomic_load(__lock, &__x, __ATOMIC_RELAXED); \
if (!__x && !_trylock_inline(__lock)) { \
if (!__x && !_trylock(__lock)) { \
break; \
} else if (++__tries & 7) { \
__builtin_ia32_pause(); \
@ -71,11 +44,11 @@
_spinlock_yield(); \
} \
} \
} while (0)
0; \
})
#define _trylock(lock) __atomic_test_and_set(lock, __ATOMIC_SEQ_CST)
int _spinlock_gettid(void);
int _trylock_debug_4(int *, const char *, const char *, int, const char *);
void _spinlock_debug_4(int *, const char *, const char *, int, const char *);
void _spinlock_yield(void);
#endif /* COSMOPOLITAN_LIBC_INTRIN_SPINLOCK_H_ */