/* Copyright Joyent, Inc. and other Node contributors. All rights reserved. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to * deal in the Software without restriction, including without limitation the * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or * sell copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. */ #include "uv.h" #include "internal.h" #include <pthread.h> #include <assert.h> #include <errno.h> #include <sys/time.h> #include <sys/resource.h> /* getrlimit() */ #include <unistd.h> /* getpagesize() */ #include <limits.h> #ifdef __MVS__ #include <sys/ipc.h> #include <sys/sem.h> #endif #if defined(__GLIBC__) && !defined(__UCLIBC__) #include <gnu/libc-version.h> /* gnu_get_libc_version() */ #endif #undef NANOSEC #define NANOSEC ((uint64_t) 1e9) #if defined(PTHREAD_BARRIER_SERIAL_THREAD) STATIC_ASSERT(sizeof(uv_barrier_t) == sizeof(pthread_barrier_t)); #endif /* Note: guard clauses should match uv_barrier_t's in include/uv/unix.h. */ #if defined(_AIX) || \ defined(__OpenBSD__) || \ !defined(PTHREAD_BARRIER_SERIAL_THREAD) int uv_barrier_init(uv_barrier_t* barrier, unsigned int count) { struct _uv_barrier* b; int rc; if (barrier == NULL || count == 0) return UV_EINVAL; b = uv__malloc(sizeof(*b)); if (b == NULL) return UV_ENOMEM; b->in = 0; b->out = 0; b->threshold = count; rc = uv_mutex_init(&b->mutex); if (rc != 0) goto error2; rc = uv_cond_init(&b->cond); if (rc != 0) goto error; barrier->b = b; return 0; error: uv_mutex_destroy(&b->mutex); error2: uv__free(b); return rc; } int uv_barrier_wait(uv_barrier_t* barrier) { struct _uv_barrier* b; int last; if (barrier == NULL || barrier->b == NULL) return UV_EINVAL; b = barrier->b; uv_mutex_lock(&b->mutex); if (++b->in == b->threshold) { b->in = 0; b->out = b->threshold; uv_cond_signal(&b->cond); } else { do uv_cond_wait(&b->cond, &b->mutex); while (b->in != 0); } last = (--b->out == 0); if (!last) uv_cond_signal(&b->cond); /* Not needed for last thread. */ uv_mutex_unlock(&b->mutex); return last; } void uv_barrier_destroy(uv_barrier_t* barrier) { struct _uv_barrier* b; b = barrier->b; uv_mutex_lock(&b->mutex); assert(b->in == 0); assert(b->out == 0); if (b->in != 0 || b->out != 0) abort(); uv_mutex_unlock(&b->mutex); uv_mutex_destroy(&b->mutex); uv_cond_destroy(&b->cond); uv__free(barrier->b); barrier->b = NULL; } #else int uv_barrier_init(uv_barrier_t* barrier, unsigned int count) { return UV__ERR(pthread_barrier_init(barrier, NULL, count)); } int uv_barrier_wait(uv_barrier_t* barrier) { int rc; rc = pthread_barrier_wait(barrier); if (rc != 0) if (rc != PTHREAD_BARRIER_SERIAL_THREAD) abort(); return rc == PTHREAD_BARRIER_SERIAL_THREAD; } void uv_barrier_destroy(uv_barrier_t* barrier) { if (pthread_barrier_destroy(barrier)) abort(); } #endif /* On MacOS, threads other than the main thread are created with a reduced * stack size by default. Adjust to RLIMIT_STACK aligned to the page size. * * On Linux, threads created by musl have a much smaller stack than threads * created by glibc (80 vs. 2048 or 4096 kB.) Follow glibc for consistency. */ static size_t thread_stack_size(void) { #if defined(__APPLE__) || defined(__linux__) struct rlimit lim; if (getrlimit(RLIMIT_STACK, &lim)) abort(); if (lim.rlim_cur != RLIM_INFINITY) { /* pthread_attr_setstacksize() expects page-aligned values. */ lim.rlim_cur -= lim.rlim_cur % (rlim_t) getpagesize(); /* Musl's PTHREAD_STACK_MIN is 2 KB on all architectures, which is * too small to safely receive signals on. * * Musl's PTHREAD_STACK_MIN + MINSIGSTKSZ == 8192 on arm64 (which has * the largest MINSIGSTKSZ of the architectures that musl supports) so * let's use that as a lower bound. * * We use a hardcoded value because PTHREAD_STACK_MIN + MINSIGSTKSZ * is between 28 and 133 KB when compiling against glibc, depending * on the architecture. */ if (lim.rlim_cur >= 8192) if (lim.rlim_cur >= PTHREAD_STACK_MIN) return lim.rlim_cur; } #endif #if !defined(__linux__) return 0; #elif defined(__PPC__) || defined(__ppc__) || defined(__powerpc__) return 4 << 20; /* glibc default. */ #else return 2 << 20; /* glibc default. */ #endif } int uv_thread_create(uv_thread_t *tid, void (*entry)(void *arg), void *arg) { uv_thread_options_t params; params.flags = UV_THREAD_NO_FLAGS; return uv_thread_create_ex(tid, ¶ms, entry, arg); } int uv_thread_create_ex(uv_thread_t* tid, const uv_thread_options_t* params, void (*entry)(void *arg), void *arg) { int err; pthread_attr_t* attr; pthread_attr_t attr_storage; size_t pagesize; size_t stack_size; /* Used to squelch a -Wcast-function-type warning. */ union { void (*in)(void*); void* (*out)(void*); } f; stack_size = params->flags & UV_THREAD_HAS_STACK_SIZE ? params->stack_size : 0; attr = NULL; if (stack_size == 0) { stack_size = thread_stack_size(); } else { pagesize = (size_t)getpagesize(); /* Round up to the nearest page boundary. */ stack_size = (stack_size + pagesize - 1) &~ (pagesize - 1); #ifdef PTHREAD_STACK_MIN if (stack_size < PTHREAD_STACK_MIN) stack_size = PTHREAD_STACK_MIN; #endif } if (stack_size > 0) { attr = &attr_storage; if (pthread_attr_init(attr)) abort(); if (pthread_attr_setstacksize(attr, stack_size)) abort(); } f.in = entry; err = pthread_create(tid, attr, f.out, arg); if (attr != NULL) pthread_attr_destroy(attr); return UV__ERR(err); } uv_thread_t uv_thread_self(void) { return pthread_self(); } int uv_thread_join(uv_thread_t *tid) { return UV__ERR(pthread_join(*tid, NULL)); } int uv_thread_equal(const uv_thread_t* t1, const uv_thread_t* t2) { return pthread_equal(*t1, *t2); } int uv_mutex_init(uv_mutex_t* mutex) { #if defined(NDEBUG) || !defined(PTHREAD_MUTEX_ERRORCHECK) return UV__ERR(pthread_mutex_init(mutex, NULL)); #else pthread_mutexattr_t attr; int err; if (pthread_mutexattr_init(&attr)) abort(); if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK)) abort(); err = pthread_mutex_init(mutex, &attr); if (pthread_mutexattr_destroy(&attr)) abort(); return UV__ERR(err); #endif } int uv_mutex_init_recursive(uv_mutex_t* mutex) { pthread_mutexattr_t attr; int err; if (pthread_mutexattr_init(&attr)) abort(); if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) abort(); err = pthread_mutex_init(mutex, &attr); if (pthread_mutexattr_destroy(&attr)) abort(); return UV__ERR(err); } void uv_mutex_destroy(uv_mutex_t* mutex) { if (pthread_mutex_destroy(mutex)) abort(); } void uv_mutex_lock(uv_mutex_t* mutex) { if (pthread_mutex_lock(mutex)) abort(); } int uv_mutex_trylock(uv_mutex_t* mutex) { int err; err = pthread_mutex_trylock(mutex); if (err) { if (err != EBUSY && err != EAGAIN) abort(); return UV_EBUSY; } return 0; } void uv_mutex_unlock(uv_mutex_t* mutex) { if (pthread_mutex_unlock(mutex)) abort(); } int uv_rwlock_init(uv_rwlock_t* rwlock) { return UV__ERR(pthread_rwlock_init(rwlock, NULL)); } void uv_rwlock_destroy(uv_rwlock_t* rwlock) { if (pthread_rwlock_destroy(rwlock)) abort(); } void uv_rwlock_rdlock(uv_rwlock_t* rwlock) { if (pthread_rwlock_rdlock(rwlock)) abort(); } int uv_rwlock_tryrdlock(uv_rwlock_t* rwlock) { int err; err = pthread_rwlock_tryrdlock(rwlock); if (err) { if (err != EBUSY && err != EAGAIN) abort(); return UV_EBUSY; } return 0; } void uv_rwlock_rdunlock(uv_rwlock_t* rwlock) { if (pthread_rwlock_unlock(rwlock)) abort(); } void uv_rwlock_wrlock(uv_rwlock_t* rwlock) { if (pthread_rwlock_wrlock(rwlock)) abort(); } int uv_rwlock_trywrlock(uv_rwlock_t* rwlock) { int err; err = pthread_rwlock_trywrlock(rwlock); if (err) { if (err != EBUSY && err != EAGAIN) abort(); return UV_EBUSY; } return 0; } void uv_rwlock_wrunlock(uv_rwlock_t* rwlock) { if (pthread_rwlock_unlock(rwlock)) abort(); } void uv_once(uv_once_t* guard, void (*callback)(void)) { if (pthread_once(guard, callback)) abort(); } #if defined(__APPLE__) && defined(__MACH__) int uv_sem_init(uv_sem_t* sem, unsigned int value) { kern_return_t err; err = semaphore_create(mach_task_self(), sem, SYNC_POLICY_FIFO, value); if (err == KERN_SUCCESS) return 0; if (err == KERN_INVALID_ARGUMENT) return UV_EINVAL; if (err == KERN_RESOURCE_SHORTAGE) return UV_ENOMEM; abort(); return UV_EINVAL; /* Satisfy the compiler. */ } void uv_sem_destroy(uv_sem_t* sem) { if (semaphore_destroy(mach_task_self(), *sem)) abort(); } void uv_sem_post(uv_sem_t* sem) { if (semaphore_signal(*sem)) abort(); } void uv_sem_wait(uv_sem_t* sem) { int r; do r = semaphore_wait(*sem); while (r == KERN_ABORTED); if (r != KERN_SUCCESS) abort(); } int uv_sem_trywait(uv_sem_t* sem) { mach_timespec_t interval; kern_return_t err; interval.tv_sec = 0; interval.tv_nsec = 0; err = semaphore_timedwait(*sem, interval); if (err == KERN_SUCCESS) return 0; if (err == KERN_OPERATION_TIMED_OUT) return UV_EAGAIN; abort(); return UV_EINVAL; /* Satisfy the compiler. */ } #else /* !(defined(__APPLE__) && defined(__MACH__)) */ #if defined(__GLIBC__) && !defined(__UCLIBC__) /* Hack around https://sourceware.org/bugzilla/show_bug.cgi?id=12674 * by providing a custom implementation for glibc < 2.21 in terms of other * concurrency primitives. * Refs: https://github.com/nodejs/node/issues/19903 */ /* To preserve ABI compatibility, we treat the uv_sem_t as storage for * a pointer to the actual struct we're using underneath. */ static uv_once_t glibc_version_check_once = UV_ONCE_INIT; static int platform_needs_custom_semaphore = 0; static void glibc_version_check(void) { const char* version = gnu_get_libc_version(); platform_needs_custom_semaphore = version[0] == '2' && version[1] == '.' && atoi(version + 2) < 21; } #elif defined(__MVS__) #define platform_needs_custom_semaphore 1 #else /* !defined(__GLIBC__) && !defined(__MVS__) */ #define platform_needs_custom_semaphore 0 #endif typedef struct uv_semaphore_s { uv_mutex_t mutex; uv_cond_t cond; unsigned int value; } uv_semaphore_t; #if (defined(__GLIBC__) && !defined(__UCLIBC__)) || \ platform_needs_custom_semaphore STATIC_ASSERT(sizeof(uv_sem_t) >= sizeof(uv_semaphore_t*)); #endif static int uv__custom_sem_init(uv_sem_t* sem_, unsigned int value) { int err; uv_semaphore_t* sem; sem = uv__malloc(sizeof(*sem)); if (sem == NULL) return UV_ENOMEM; if ((err = uv_mutex_init(&sem->mutex)) != 0) { uv__free(sem); return err; } if ((err = uv_cond_init(&sem->cond)) != 0) { uv_mutex_destroy(&sem->mutex); uv__free(sem); return err; } sem->value = value; *(uv_semaphore_t**)sem_ = sem; return 0; } static void uv__custom_sem_destroy(uv_sem_t* sem_) { uv_semaphore_t* sem; sem = *(uv_semaphore_t**)sem_; uv_cond_destroy(&sem->cond); uv_mutex_destroy(&sem->mutex); uv__free(sem); } static void uv__custom_sem_post(uv_sem_t* sem_) { uv_semaphore_t* sem; sem = *(uv_semaphore_t**)sem_; uv_mutex_lock(&sem->mutex); sem->value++; if (sem->value == 1) uv_cond_signal(&sem->cond); uv_mutex_unlock(&sem->mutex); } static void uv__custom_sem_wait(uv_sem_t* sem_) { uv_semaphore_t* sem; sem = *(uv_semaphore_t**)sem_; uv_mutex_lock(&sem->mutex); while (sem->value == 0) uv_cond_wait(&sem->cond, &sem->mutex); sem->value--; uv_mutex_unlock(&sem->mutex); } static int uv__custom_sem_trywait(uv_sem_t* sem_) { uv_semaphore_t* sem; sem = *(uv_semaphore_t**)sem_; if (uv_mutex_trylock(&sem->mutex) != 0) return UV_EAGAIN; if (sem->value == 0) { uv_mutex_unlock(&sem->mutex); return UV_EAGAIN; } sem->value--; uv_mutex_unlock(&sem->mutex); return 0; } static int uv__sem_init(uv_sem_t* sem, unsigned int value) { if (sem_init(sem, 0, value)) return UV__ERR(errno); return 0; } static void uv__sem_destroy(uv_sem_t* sem) { if (sem_destroy(sem)) abort(); } static void uv__sem_post(uv_sem_t* sem) { if (sem_post(sem)) abort(); } static void uv__sem_wait(uv_sem_t* sem) { int r; do r = sem_wait(sem); while (r == -1 && errno == EINTR); if (r) abort(); } static int uv__sem_trywait(uv_sem_t* sem) { int r; do r = sem_trywait(sem); while (r == -1 && errno == EINTR); if (r) { if (errno == EAGAIN) return UV_EAGAIN; abort(); } return 0; } int uv_sem_init(uv_sem_t* sem, unsigned int value) { #if defined(__GLIBC__) && !defined(__UCLIBC__) uv_once(&glibc_version_check_once, glibc_version_check); #endif if (platform_needs_custom_semaphore) return uv__custom_sem_init(sem, value); else return uv__sem_init(sem, value); } void uv_sem_destroy(uv_sem_t* sem) { if (platform_needs_custom_semaphore) uv__custom_sem_destroy(sem); else uv__sem_destroy(sem); } void uv_sem_post(uv_sem_t* sem) { if (platform_needs_custom_semaphore) uv__custom_sem_post(sem); else uv__sem_post(sem); } void uv_sem_wait(uv_sem_t* sem) { if (platform_needs_custom_semaphore) uv__custom_sem_wait(sem); else uv__sem_wait(sem); } int uv_sem_trywait(uv_sem_t* sem) { if (platform_needs_custom_semaphore) return uv__custom_sem_trywait(sem); else return uv__sem_trywait(sem); } #endif /* defined(__APPLE__) && defined(__MACH__) */ #if defined(__APPLE__) && defined(__MACH__) || defined(__MVS__) int uv_cond_init(uv_cond_t* cond) { return UV__ERR(pthread_cond_init(cond, NULL)); } #else /* !(defined(__APPLE__) && defined(__MACH__)) */ int uv_cond_init(uv_cond_t* cond) { pthread_condattr_t attr; int err; err = pthread_condattr_init(&attr); if (err) return UV__ERR(err); #if !(defined(__ANDROID_API__) && __ANDROID_API__ < 21) err = pthread_condattr_setclock(&attr, CLOCK_MONOTONIC); if (err) goto error2; #endif err = pthread_cond_init(cond, &attr); if (err) goto error2; err = pthread_condattr_destroy(&attr); if (err) goto error; return 0; error: pthread_cond_destroy(cond); error2: pthread_condattr_destroy(&attr); return UV__ERR(err); } #endif /* defined(__APPLE__) && defined(__MACH__) */ void uv_cond_destroy(uv_cond_t* cond) { #if defined(__APPLE__) && defined(__MACH__) /* It has been reported that destroying condition variables that have been * signalled but not waited on can sometimes result in application crashes. * See https://codereview.chromium.org/1323293005. */ pthread_mutex_t mutex; struct timespec ts; int err; if (pthread_mutex_init(&mutex, NULL)) abort(); if (pthread_mutex_lock(&mutex)) abort(); ts.tv_sec = 0; ts.tv_nsec = 1; err = pthread_cond_timedwait_relative_np(cond, &mutex, &ts); if (err != 0 && err != ETIMEDOUT) abort(); if (pthread_mutex_unlock(&mutex)) abort(); if (pthread_mutex_destroy(&mutex)) abort(); #endif /* defined(__APPLE__) && defined(__MACH__) */ if (pthread_cond_destroy(cond)) abort(); } void uv_cond_signal(uv_cond_t* cond) { if (pthread_cond_signal(cond)) abort(); } void uv_cond_broadcast(uv_cond_t* cond) { if (pthread_cond_broadcast(cond)) abort(); } void uv_cond_wait(uv_cond_t* cond, uv_mutex_t* mutex) { if (pthread_cond_wait(cond, mutex)) abort(); } int uv_cond_timedwait(uv_cond_t* cond, uv_mutex_t* mutex, uint64_t timeout) { int r; struct timespec ts; #if defined(__MVS__) struct timeval tv; #endif #if defined(__APPLE__) && defined(__MACH__) ts.tv_sec = timeout / NANOSEC; ts.tv_nsec = timeout % NANOSEC; r = pthread_cond_timedwait_relative_np(cond, mutex, &ts); #else #if defined(__MVS__) if (gettimeofday(&tv, NULL)) abort(); timeout += tv.tv_sec * NANOSEC + tv.tv_usec * 1e3; #else timeout += uv__hrtime(UV_CLOCK_PRECISE); #endif ts.tv_sec = timeout / NANOSEC; ts.tv_nsec = timeout % NANOSEC; #if defined(__ANDROID_API__) && __ANDROID_API__ < 21 /* * The bionic pthread implementation doesn't support CLOCK_MONOTONIC, * but has this alternative function instead. */ r = pthread_cond_timedwait_monotonic_np(cond, mutex, &ts); #else r = pthread_cond_timedwait(cond, mutex, &ts); #endif /* __ANDROID_API__ */ #endif if (r == 0) return 0; if (r == ETIMEDOUT) return UV_ETIMEDOUT; abort(); #ifndef __SUNPRO_C return UV_EINVAL; /* Satisfy the compiler. */ #endif } int uv_key_create(uv_key_t* key) { return UV__ERR(pthread_key_create(key, NULL)); } void uv_key_delete(uv_key_t* key) { if (pthread_key_delete(*key)) abort(); } void* uv_key_get(uv_key_t* key) { return pthread_getspecific(*key); } void uv_key_set(uv_key_t* key, void* value) { if (pthread_setspecific(*key, value)) abort(); }