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-rw-r--r--deps/jemalloc/src/mutex.c228
1 files changed, 228 insertions, 0 deletions
diff --git a/deps/jemalloc/src/mutex.c b/deps/jemalloc/src/mutex.c
new file mode 100644
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--- /dev/null
+++ b/deps/jemalloc/src/mutex.c
@@ -0,0 +1,228 @@
+#include "jemalloc/internal/jemalloc_preamble.h"
+#include "jemalloc/internal/jemalloc_internal_includes.h"
+
+#include "jemalloc/internal/assert.h"
+#include "jemalloc/internal/malloc_io.h"
+#include "jemalloc/internal/spin.h"
+
+#ifndef _CRT_SPINCOUNT
+#define _CRT_SPINCOUNT 4000
+#endif
+
+/*
+ * Based on benchmark results, a fixed spin with this amount of retries works
+ * well for our critical sections.
+ */
+int64_t opt_mutex_max_spin = 600;
+
+/******************************************************************************/
+/* Data. */
+
+#ifdef JEMALLOC_LAZY_LOCK
+bool isthreaded = false;
+#endif
+#ifdef JEMALLOC_MUTEX_INIT_CB
+static bool postpone_init = true;
+static malloc_mutex_t *postponed_mutexes = NULL;
+#endif
+
+/******************************************************************************/
+/*
+ * We intercept pthread_create() calls in order to toggle isthreaded if the
+ * process goes multi-threaded.
+ */
+
+#if defined(JEMALLOC_LAZY_LOCK) && !defined(_WIN32)
+JEMALLOC_EXPORT int
+pthread_create(pthread_t *__restrict thread,
+ const pthread_attr_t *__restrict attr, void *(*start_routine)(void *),
+ void *__restrict arg) {
+ return pthread_create_wrapper(thread, attr, start_routine, arg);
+}
+#endif
+
+/******************************************************************************/
+
+#ifdef JEMALLOC_MUTEX_INIT_CB
+JEMALLOC_EXPORT int _pthread_mutex_init_calloc_cb(pthread_mutex_t *mutex,
+ void *(calloc_cb)(size_t, size_t));
+#endif
+
+void
+malloc_mutex_lock_slow(malloc_mutex_t *mutex) {
+ mutex_prof_data_t *data = &mutex->prof_data;
+ nstime_t before;
+
+ if (ncpus == 1) {
+ goto label_spin_done;
+ }
+
+ int cnt = 0;
+ do {
+ spin_cpu_spinwait();
+ if (!atomic_load_b(&mutex->locked, ATOMIC_RELAXED)
+ && !malloc_mutex_trylock_final(mutex)) {
+ data->n_spin_acquired++;
+ return;
+ }
+ } while (cnt++ < opt_mutex_max_spin || opt_mutex_max_spin == -1);
+
+ if (!config_stats) {
+ /* Only spin is useful when stats is off. */
+ malloc_mutex_lock_final(mutex);
+ return;
+ }
+label_spin_done:
+ nstime_init_update(&before);
+ /* Copy before to after to avoid clock skews. */
+ nstime_t after;
+ nstime_copy(&after, &before);
+ uint32_t n_thds = atomic_fetch_add_u32(&data->n_waiting_thds, 1,
+ ATOMIC_RELAXED) + 1;
+ /* One last try as above two calls may take quite some cycles. */
+ if (!malloc_mutex_trylock_final(mutex)) {
+ atomic_fetch_sub_u32(&data->n_waiting_thds, 1, ATOMIC_RELAXED);
+ data->n_spin_acquired++;
+ return;
+ }
+
+ /* True slow path. */
+ malloc_mutex_lock_final(mutex);
+ /* Update more slow-path only counters. */
+ atomic_fetch_sub_u32(&data->n_waiting_thds, 1, ATOMIC_RELAXED);
+ nstime_update(&after);
+
+ nstime_t delta;
+ nstime_copy(&delta, &after);
+ nstime_subtract(&delta, &before);
+
+ data->n_wait_times++;
+ nstime_add(&data->tot_wait_time, &delta);
+ if (nstime_compare(&data->max_wait_time, &delta) < 0) {
+ nstime_copy(&data->max_wait_time, &delta);
+ }
+ if (n_thds > data->max_n_thds) {
+ data->max_n_thds = n_thds;
+ }
+}
+
+static void
+mutex_prof_data_init(mutex_prof_data_t *data) {
+ memset(data, 0, sizeof(mutex_prof_data_t));
+ nstime_init_zero(&data->max_wait_time);
+ nstime_init_zero(&data->tot_wait_time);
+ data->prev_owner = NULL;
+}
+
+void
+malloc_mutex_prof_data_reset(tsdn_t *tsdn, malloc_mutex_t *mutex) {
+ malloc_mutex_assert_owner(tsdn, mutex);
+ mutex_prof_data_init(&mutex->prof_data);
+}
+
+static int
+mutex_addr_comp(const witness_t *witness1, void *mutex1,
+ const witness_t *witness2, void *mutex2) {
+ assert(mutex1 != NULL);
+ assert(mutex2 != NULL);
+ uintptr_t mu1int = (uintptr_t)mutex1;
+ uintptr_t mu2int = (uintptr_t)mutex2;
+ if (mu1int < mu2int) {
+ return -1;
+ } else if (mu1int == mu2int) {
+ return 0;
+ } else {
+ return 1;
+ }
+}
+
+bool
+malloc_mutex_init(malloc_mutex_t *mutex, const char *name,
+ witness_rank_t rank, malloc_mutex_lock_order_t lock_order) {
+ mutex_prof_data_init(&mutex->prof_data);
+#ifdef _WIN32
+# if _WIN32_WINNT >= 0x0600
+ InitializeSRWLock(&mutex->lock);
+# else
+ if (!InitializeCriticalSectionAndSpinCount(&mutex->lock,
+ _CRT_SPINCOUNT)) {
+ return true;
+ }
+# endif
+#elif (defined(JEMALLOC_OS_UNFAIR_LOCK))
+ mutex->lock = OS_UNFAIR_LOCK_INIT;
+#elif (defined(JEMALLOC_MUTEX_INIT_CB))
+ if (postpone_init) {
+ mutex->postponed_next = postponed_mutexes;
+ postponed_mutexes = mutex;
+ } else {
+ if (_pthread_mutex_init_calloc_cb(&mutex->lock,
+ bootstrap_calloc) != 0) {
+ return true;
+ }
+ }
+#else
+ pthread_mutexattr_t attr;
+
+ if (pthread_mutexattr_init(&attr) != 0) {
+ return true;
+ }
+ pthread_mutexattr_settype(&attr, MALLOC_MUTEX_TYPE);
+ if (pthread_mutex_init(&mutex->lock, &attr) != 0) {
+ pthread_mutexattr_destroy(&attr);
+ return true;
+ }
+ pthread_mutexattr_destroy(&attr);
+#endif
+ if (config_debug) {
+ mutex->lock_order = lock_order;
+ if (lock_order == malloc_mutex_address_ordered) {
+ witness_init(&mutex->witness, name, rank,
+ mutex_addr_comp, mutex);
+ } else {
+ witness_init(&mutex->witness, name, rank, NULL, NULL);
+ }
+ }
+ return false;
+}
+
+void
+malloc_mutex_prefork(tsdn_t *tsdn, malloc_mutex_t *mutex) {
+ malloc_mutex_lock(tsdn, mutex);
+}
+
+void
+malloc_mutex_postfork_parent(tsdn_t *tsdn, malloc_mutex_t *mutex) {
+ malloc_mutex_unlock(tsdn, mutex);
+}
+
+void
+malloc_mutex_postfork_child(tsdn_t *tsdn, malloc_mutex_t *mutex) {
+#ifdef JEMALLOC_MUTEX_INIT_CB
+ malloc_mutex_unlock(tsdn, mutex);
+#else
+ if (malloc_mutex_init(mutex, mutex->witness.name,
+ mutex->witness.rank, mutex->lock_order)) {
+ malloc_printf("<jemalloc>: Error re-initializing mutex in "
+ "child\n");
+ if (opt_abort) {
+ abort();
+ }
+ }
+#endif
+}
+
+bool
+malloc_mutex_boot(void) {
+#ifdef JEMALLOC_MUTEX_INIT_CB
+ postpone_init = false;
+ while (postponed_mutexes != NULL) {
+ if (_pthread_mutex_init_calloc_cb(&postponed_mutexes->lock,
+ bootstrap_calloc) != 0) {
+ return true;
+ }
+ postponed_mutexes = postponed_mutexes->postponed_next;
+ }
+#endif
+ return false;
+}