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Diffstat (limited to 'deps/jemalloc/include/jemalloc/internal/mutex.h')
| -rw-r--r-- | deps/jemalloc/include/jemalloc/internal/mutex.h | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/deps/jemalloc/include/jemalloc/internal/mutex.h b/deps/jemalloc/include/jemalloc/internal/mutex.h new file mode 100644 index 000000000..7c24f0725 --- /dev/null +++ b/deps/jemalloc/include/jemalloc/internal/mutex.h @@ -0,0 +1,288 @@ +#ifndef JEMALLOC_INTERNAL_MUTEX_H +#define JEMALLOC_INTERNAL_MUTEX_H + +#include "jemalloc/internal/atomic.h" +#include "jemalloc/internal/mutex_prof.h" +#include "jemalloc/internal/tsd.h" +#include "jemalloc/internal/witness.h" + +typedef enum { + /* Can only acquire one mutex of a given witness rank at a time. */ + malloc_mutex_rank_exclusive, + /* + * Can acquire multiple mutexes of the same witness rank, but in + * address-ascending order only. + */ + malloc_mutex_address_ordered +} malloc_mutex_lock_order_t; + +typedef struct malloc_mutex_s malloc_mutex_t; +struct malloc_mutex_s { + union { + struct { + /* + * prof_data is defined first to reduce cacheline + * bouncing: the data is not touched by the mutex holder + * during unlocking, while might be modified by + * contenders. Having it before the mutex itself could + * avoid prefetching a modified cacheline (for the + * unlocking thread). + */ + mutex_prof_data_t prof_data; +#ifdef _WIN32 +# if _WIN32_WINNT >= 0x0600 + SRWLOCK lock; +# else + CRITICAL_SECTION lock; +# endif +#elif (defined(JEMALLOC_OS_UNFAIR_LOCK)) + os_unfair_lock lock; +#elif (defined(JEMALLOC_MUTEX_INIT_CB)) + pthread_mutex_t lock; + malloc_mutex_t *postponed_next; +#else + pthread_mutex_t lock; +#endif + /* + * Hint flag to avoid exclusive cache line contention + * during spin waiting + */ + atomic_b_t locked; + }; + /* + * We only touch witness when configured w/ debug. However we + * keep the field in a union when !debug so that we don't have + * to pollute the code base with #ifdefs, while avoid paying the + * memory cost. + */ +#if !defined(JEMALLOC_DEBUG) + witness_t witness; + malloc_mutex_lock_order_t lock_order; +#endif + }; + +#if defined(JEMALLOC_DEBUG) + witness_t witness; + malloc_mutex_lock_order_t lock_order; +#endif +}; + +/* + * Based on benchmark results, a fixed spin with this amount of retries works + * well for our critical sections. + */ +#define MALLOC_MUTEX_MAX_SPIN 250 + +#ifdef _WIN32 +# if _WIN32_WINNT >= 0x0600 +# define MALLOC_MUTEX_LOCK(m) AcquireSRWLockExclusive(&(m)->lock) +# define MALLOC_MUTEX_UNLOCK(m) ReleaseSRWLockExclusive(&(m)->lock) +# define MALLOC_MUTEX_TRYLOCK(m) (!TryAcquireSRWLockExclusive(&(m)->lock)) +# else +# define MALLOC_MUTEX_LOCK(m) EnterCriticalSection(&(m)->lock) +# define MALLOC_MUTEX_UNLOCK(m) LeaveCriticalSection(&(m)->lock) +# define MALLOC_MUTEX_TRYLOCK(m) (!TryEnterCriticalSection(&(m)->lock)) +# endif +#elif (defined(JEMALLOC_OS_UNFAIR_LOCK)) +# define MALLOC_MUTEX_LOCK(m) os_unfair_lock_lock(&(m)->lock) +# define MALLOC_MUTEX_UNLOCK(m) os_unfair_lock_unlock(&(m)->lock) +# define MALLOC_MUTEX_TRYLOCK(m) (!os_unfair_lock_trylock(&(m)->lock)) +#else +# define MALLOC_MUTEX_LOCK(m) pthread_mutex_lock(&(m)->lock) +# define MALLOC_MUTEX_UNLOCK(m) pthread_mutex_unlock(&(m)->lock) +# define MALLOC_MUTEX_TRYLOCK(m) (pthread_mutex_trylock(&(m)->lock) != 0) +#endif + +#define LOCK_PROF_DATA_INITIALIZER \ + {NSTIME_ZERO_INITIALIZER, NSTIME_ZERO_INITIALIZER, 0, 0, 0, \ + ATOMIC_INIT(0), 0, NULL, 0} + +#ifdef _WIN32 +# define MALLOC_MUTEX_INITIALIZER +#elif (defined(JEMALLOC_OS_UNFAIR_LOCK)) +# if defined(JEMALLOC_DEBUG) +# define MALLOC_MUTEX_INITIALIZER \ + {{{LOCK_PROF_DATA_INITIALIZER, OS_UNFAIR_LOCK_INIT, ATOMIC_INIT(false)}}, \ + WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT), 0} +# else +# define MALLOC_MUTEX_INITIALIZER \ + {{{LOCK_PROF_DATA_INITIALIZER, OS_UNFAIR_LOCK_INIT, ATOMIC_INIT(false)}}, \ + WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT)} +# endif +#elif (defined(JEMALLOC_MUTEX_INIT_CB)) +# if (defined(JEMALLOC_DEBUG)) +# define MALLOC_MUTEX_INITIALIZER \ + {{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, NULL, ATOMIC_INIT(false)}}, \ + WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT), 0} +# else +# define MALLOC_MUTEX_INITIALIZER \ + {{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, NULL, ATOMIC_INIT(false)}}, \ + WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT)} +# endif + +#else +# define MALLOC_MUTEX_TYPE PTHREAD_MUTEX_DEFAULT +# if defined(JEMALLOC_DEBUG) +# define MALLOC_MUTEX_INITIALIZER \ + {{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, ATOMIC_INIT(false)}}, \ + WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT), 0} +# else +# define MALLOC_MUTEX_INITIALIZER \ + {{{LOCK_PROF_DATA_INITIALIZER, PTHREAD_MUTEX_INITIALIZER, ATOMIC_INIT(false)}}, \ + WITNESS_INITIALIZER("mutex", WITNESS_RANK_OMIT)} +# endif +#endif + +#ifdef JEMALLOC_LAZY_LOCK +extern bool isthreaded; +#else +# undef isthreaded /* Undo private_namespace.h definition. */ +# define isthreaded true +#endif + +bool malloc_mutex_init(malloc_mutex_t *mutex, const char *name, + witness_rank_t rank, malloc_mutex_lock_order_t lock_order); +void malloc_mutex_prefork(tsdn_t *tsdn, malloc_mutex_t *mutex); +void malloc_mutex_postfork_parent(tsdn_t *tsdn, malloc_mutex_t *mutex); +void malloc_mutex_postfork_child(tsdn_t *tsdn, malloc_mutex_t *mutex); +bool malloc_mutex_boot(void); +void malloc_mutex_prof_data_reset(tsdn_t *tsdn, malloc_mutex_t *mutex); + +void malloc_mutex_lock_slow(malloc_mutex_t *mutex); + +static inline void +malloc_mutex_lock_final(malloc_mutex_t *mutex) { + MALLOC_MUTEX_LOCK(mutex); + atomic_store_b(&mutex->locked, true, ATOMIC_RELAXED); +} + +static inline bool +malloc_mutex_trylock_final(malloc_mutex_t *mutex) { + return MALLOC_MUTEX_TRYLOCK(mutex); +} + +static inline void +mutex_owner_stats_update(tsdn_t *tsdn, malloc_mutex_t *mutex) { + if (config_stats) { + mutex_prof_data_t *data = &mutex->prof_data; + data->n_lock_ops++; + if (data->prev_owner != tsdn) { + data->prev_owner = tsdn; + data->n_owner_switches++; + } + } +} + +/* Trylock: return false if the lock is successfully acquired. */ +static inline bool +malloc_mutex_trylock(tsdn_t *tsdn, malloc_mutex_t *mutex) { + witness_assert_not_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness); + if (isthreaded) { + if (malloc_mutex_trylock_final(mutex)) { + atomic_store_b(&mutex->locked, true, ATOMIC_RELAXED); + return true; + } + mutex_owner_stats_update(tsdn, mutex); + } + witness_lock(tsdn_witness_tsdp_get(tsdn), &mutex->witness); + + return false; +} + +/* Aggregate lock prof data. */ +static inline void +malloc_mutex_prof_merge(mutex_prof_data_t *sum, mutex_prof_data_t *data) { + nstime_add(&sum->tot_wait_time, &data->tot_wait_time); + if (nstime_compare(&sum->max_wait_time, &data->max_wait_time) < 0) { + nstime_copy(&sum->max_wait_time, &data->max_wait_time); + } + + sum->n_wait_times += data->n_wait_times; + sum->n_spin_acquired += data->n_spin_acquired; + + if (sum->max_n_thds < data->max_n_thds) { + sum->max_n_thds = data->max_n_thds; + } + uint32_t cur_n_waiting_thds = atomic_load_u32(&sum->n_waiting_thds, + ATOMIC_RELAXED); + uint32_t new_n_waiting_thds = cur_n_waiting_thds + atomic_load_u32( + &data->n_waiting_thds, ATOMIC_RELAXED); + atomic_store_u32(&sum->n_waiting_thds, new_n_waiting_thds, + ATOMIC_RELAXED); + sum->n_owner_switches += data->n_owner_switches; + sum->n_lock_ops += data->n_lock_ops; +} + +static inline void +malloc_mutex_lock(tsdn_t *tsdn, malloc_mutex_t *mutex) { + witness_assert_not_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness); + if (isthreaded) { + if (malloc_mutex_trylock_final(mutex)) { + malloc_mutex_lock_slow(mutex); + atomic_store_b(&mutex->locked, true, ATOMIC_RELAXED); + } + mutex_owner_stats_update(tsdn, mutex); + } + witness_lock(tsdn_witness_tsdp_get(tsdn), &mutex->witness); +} + +static inline void +malloc_mutex_unlock(tsdn_t *tsdn, malloc_mutex_t *mutex) { + atomic_store_b(&mutex->locked, false, ATOMIC_RELAXED); + witness_unlock(tsdn_witness_tsdp_get(tsdn), &mutex->witness); + if (isthreaded) { + MALLOC_MUTEX_UNLOCK(mutex); + } +} + +static inline void +malloc_mutex_assert_owner(tsdn_t *tsdn, malloc_mutex_t *mutex) { + witness_assert_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness); +} + +static inline void +malloc_mutex_assert_not_owner(tsdn_t *tsdn, malloc_mutex_t *mutex) { + witness_assert_not_owner(tsdn_witness_tsdp_get(tsdn), &mutex->witness); +} + +/* Copy the prof data from mutex for processing. */ +static inline void +malloc_mutex_prof_read(tsdn_t *tsdn, mutex_prof_data_t *data, + malloc_mutex_t *mutex) { + mutex_prof_data_t *source = &mutex->prof_data; + /* Can only read holding the mutex. */ + malloc_mutex_assert_owner(tsdn, mutex); + + /* + * Not *really* allowed (we shouldn't be doing non-atomic loads of + * atomic data), but the mutex protection makes this safe, and writing + * a member-for-member copy is tedious for this situation. + */ + *data = *source; + /* n_wait_thds is not reported (modified w/o locking). */ + atomic_store_u32(&data->n_waiting_thds, 0, ATOMIC_RELAXED); +} + +static inline void +malloc_mutex_prof_accum(tsdn_t *tsdn, mutex_prof_data_t *data, + malloc_mutex_t *mutex) { + mutex_prof_data_t *source = &mutex->prof_data; + /* Can only read holding the mutex. */ + malloc_mutex_assert_owner(tsdn, mutex); + + nstime_add(&data->tot_wait_time, &source->tot_wait_time); + if (nstime_compare(&source->max_wait_time, &data->max_wait_time) > 0) { + nstime_copy(&data->max_wait_time, &source->max_wait_time); + } + data->n_wait_times += source->n_wait_times; + data->n_spin_acquired += source->n_spin_acquired; + if (data->max_n_thds < source->max_n_thds) { + data->max_n_thds = source->max_n_thds; + } + /* n_wait_thds is not reported. */ + atomic_store_u32(&data->n_waiting_thds, 0, ATOMIC_RELAXED); + data->n_owner_switches += source->n_owner_switches; + data->n_lock_ops += source->n_lock_ops; +} + +#endif /* JEMALLOC_INTERNAL_MUTEX_H */ |