From 357fd25a4b7b3dde056de295a0e72eec6e878003 Mon Sep 17 00:00:00 2001 From: dimitri staessens Date: Sat, 1 Apr 2017 17:30:25 +0200 Subject: lib: Lockless implementation of the rbuff --- src/lib/shm_rbuff.c | 408 +--------------------------------------------------- 1 file changed, 4 insertions(+), 404 deletions(-) (limited to 'src/lib/shm_rbuff.c') diff --git a/src/lib/shm_rbuff.c b/src/lib/shm_rbuff.c index b8db7c19..dc1d9f0a 100644 --- a/src/lib/shm_rbuff.c +++ b/src/lib/shm_rbuff.c @@ -1,406 +1,6 @@ -/* - * Ouroboros - Copyright (C) 2016 - 2017 - * - * Ring buffer for incoming SDUs - * - * Dimitri Staessens - * Sander Vrijders - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public License - * version 2.1 as published by the Free Software Foundation. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - * 02110-1301 USA - */ - -#include -#include -#include -#include -#include - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#define FN_MAX_CHARS 255 -#define RB_OPEN 0 -#define RB_CLOSED 1 - -#define SHM_RBUFF_FILE_SIZE ((SHM_BUFFER_SIZE) * sizeof(ssize_t) \ - + 3 * sizeof(size_t) \ - + sizeof(pthread_mutex_t) \ - + 2 * sizeof (pthread_cond_t)) - -#define shm_rbuff_used(rb) ((*rb->head + (SHM_BUFFER_SIZE) - *rb->tail) \ - & ((SHM_BUFFER_SIZE) - 1)) -#define shm_rbuff_free(rb) (shm_rbuff_used(rb) + 1 < (SHM_BUFFER_SIZE)) -#define shm_rbuff_empty(rb) (*rb->head == *rb->tail) -#define head_el_ptr(rb) (rb->shm_base + *rb->head) -#define tail_el_ptr(rb) (rb->shm_base + *rb->tail) - -struct shm_rbuff { - ssize_t * shm_base; /* start of entry */ - size_t * head; /* start of ringbuffer head */ - size_t * tail; /* start of ringbuffer tail */ - size_t * acl; /* access control */ - pthread_mutex_t * lock; /* lock all free space in shm */ - pthread_cond_t * add; /* SDU arrived */ - pthread_cond_t * del; /* SDU removed */ - pid_t api; /* api of the owner */ - int port_id; /* port_id of the flow */ -}; - -struct shm_rbuff * shm_rbuff_create(pid_t api, int port_id) -{ - struct shm_rbuff * rb; - int shm_fd; - ssize_t * shm_base; - pthread_mutexattr_t mattr; - pthread_condattr_t cattr; - char fn[FN_MAX_CHARS]; - mode_t mask; - - sprintf(fn, SHM_RBUFF_PREFIX "%d.%d", api, port_id); - - rb = malloc(sizeof(*rb)); - if (rb == NULL) - return NULL; - - mask = umask(0); - - shm_fd = shm_open(fn, O_CREAT | O_EXCL | O_RDWR, 0666); - if (shm_fd == -1) { - free(rb); - return NULL; - } - - umask(mask); - - if (ftruncate(shm_fd, SHM_RBUFF_FILE_SIZE - 1) < 0) { - free(rb); - close(shm_fd); - return NULL; - } - - shm_base = mmap(NULL, - SHM_RBUFF_FILE_SIZE, - PROT_READ | PROT_WRITE, - MAP_SHARED, - shm_fd, - 0); - - close(shm_fd); - - if (shm_base == MAP_FAILED) { - shm_unlink(fn); - free(rb); - return NULL; - } - - rb->shm_base = shm_base; - rb->head = (size_t *) (rb->shm_base + (SHM_BUFFER_SIZE)); - rb->tail = rb->head + 1; - rb->acl = rb->tail + 1; - rb->lock = (pthread_mutex_t *) (rb->acl + 1); - rb->add = (pthread_cond_t *) (rb->lock + 1); - rb->del = rb->add + 1; - - pthread_mutexattr_init(&mattr); -#ifndef __APPLE__ - pthread_mutexattr_setrobust(&mattr, PTHREAD_MUTEX_ROBUST); -#endif - pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED); - pthread_mutex_init(rb->lock, &mattr); - - pthread_condattr_init(&cattr); - pthread_condattr_setpshared(&cattr, PTHREAD_PROCESS_SHARED); -#ifndef __APPLE__ - pthread_condattr_setclock(&cattr, PTHREAD_COND_CLOCK); -#endif - pthread_cond_init(rb->add, &cattr); - pthread_cond_init(rb->del, &cattr); - - *rb->acl = RB_OPEN; - *rb->head = 0; - *rb->tail = 0; - - rb->api = api; - rb->port_id = port_id; - - return rb; -} - -struct shm_rbuff * shm_rbuff_open(pid_t api, int port_id) -{ - struct shm_rbuff * rb; - int shm_fd; - ssize_t * shm_base; - char fn[FN_MAX_CHARS]; - - sprintf(fn, SHM_RBUFF_PREFIX "%d.%d", api, port_id); - - rb = malloc(sizeof(*rb)); - if (rb == NULL) - return NULL; - - shm_fd = shm_open(fn, O_RDWR, 0666); - if (shm_fd == -1) { - free(rb); - return NULL; - } - - shm_base = mmap(NULL, - SHM_RBUFF_FILE_SIZE, - PROT_READ | PROT_WRITE, - MAP_SHARED, - shm_fd, - 0); - - close(shm_fd); - - if (shm_base == MAP_FAILED) { - shm_unlink(fn); - free(rb); - return NULL; - } - - rb->shm_base = shm_base; - rb->head = (size_t *) (rb->shm_base + (SHM_BUFFER_SIZE)); - rb->tail = rb->head + 1; - rb->acl = rb->tail + 1; - rb->lock = (pthread_mutex_t *) (rb->acl + 1); - rb->add = (pthread_cond_t *) (rb->lock + 1); - rb->del = rb->add + 1; - - rb->api = api; - rb->port_id = port_id; - - return rb; -} - -void shm_rbuff_close(struct shm_rbuff * rb) -{ - assert(rb); - - munmap(rb->shm_base, SHM_RBUFF_FILE_SIZE); - - free(rb); -} - -void shm_rbuff_destroy(struct shm_rbuff * rb) -{ - char fn[FN_MAX_CHARS]; - - assert(rb); - -#ifdef CONFIG_OUROBOROS_DEBUG - pthread_mutex_lock(rb->lock); - - assert(shm_rbuff_empty(rb)); - - pthread_mutex_unlock(rb->lock); -#endif - sprintf(fn, SHM_RBUFF_PREFIX "%d.%d", rb->api, rb->port_id); - - munmap(rb->shm_base, SHM_RBUFF_FILE_SIZE); - shm_unlink(fn); - - free(rb); -} - -int shm_rbuff_write(struct shm_rbuff * rb, size_t idx) -{ - assert(rb); - assert(idx < SHM_BUFFER_SIZE); - -#ifdef __APPLE__ - pthread_mutex_lock(rb->lock); -#else - if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - if (*rb->acl == RB_CLOSED) { - pthread_mutex_unlock(rb->lock); - return -ENOTALLOC; - } - - if (!shm_rbuff_free(rb)) { - pthread_mutex_unlock(rb->lock); - return -EAGAIN; - } - - if (shm_rbuff_empty(rb)) - pthread_cond_broadcast(rb->add); - - *head_el_ptr(rb) = (ssize_t) idx; - *rb->head = (*rb->head + 1) & ((SHM_BUFFER_SIZE) -1); - - pthread_mutex_unlock(rb->lock); - - return 0; -} - -ssize_t shm_rbuff_read(struct shm_rbuff * rb) -{ - ssize_t ret = 0; - - assert(rb); - -#ifdef __APPLE__ - pthread_mutex_lock(rb->lock); -#else - if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - if (shm_rbuff_empty(rb)) { - pthread_mutex_unlock(rb->lock); - return -EAGAIN; - } - - ret = *tail_el_ptr(rb); - *rb->tail = (*rb->tail + 1) & ((SHM_BUFFER_SIZE) - 1); - pthread_cond_broadcast(rb->del); - - pthread_mutex_unlock(rb->lock); - - return ret; -} - -ssize_t shm_rbuff_read_b(struct shm_rbuff * rb, - const struct timespec * timeout) -{ - struct timespec abstime; - ssize_t idx = -1; - - assert(rb); - -#ifdef __APPLE__ - pthread_mutex_lock(rb->lock); -#else - if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - if (timeout != NULL) { - clock_gettime(PTHREAD_COND_CLOCK, &abstime); - ts_add(&abstime, timeout, &abstime); - } - - pthread_cleanup_push((void(*)(void *))pthread_mutex_unlock, - (void *) rb->lock); - - while (shm_rbuff_empty(rb) && (idx != -ETIMEDOUT)) { - if (timeout != NULL) - idx = -pthread_cond_timedwait(rb->add, - rb->lock, - &abstime); - else - idx = -pthread_cond_wait(rb->add, rb->lock); -#ifndef __APPLE__ - if (idx == -EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - } - - if (idx != -ETIMEDOUT) { - idx = *tail_el_ptr(rb); - *rb->tail = (*rb->tail + 1) & ((SHM_BUFFER_SIZE) - 1); - pthread_cond_broadcast(rb->del); - } - - pthread_cleanup_pop(true); - - return idx; -} - -void shm_rbuff_block(struct shm_rbuff * rb) -{ - assert(rb); - -#ifdef __APPLE__ - pthread_mutex_lock(rb->lock); -#else - if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - *rb->acl = RB_CLOSED; - - pthread_mutex_unlock(rb->lock); -} - -void shm_rbuff_unblock(struct shm_rbuff * rb) -{ - assert(rb); - -#ifdef __APPLE__ - pthread_mutex_lock(rb->lock); -#else - if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - *rb->acl = RB_OPEN; - - pthread_mutex_unlock(rb->lock); -} - -void shm_rbuff_fini(struct shm_rbuff * rb) -{ - assert(rb); - -#ifdef __APPLE__ - pthread_mutex_lock(rb->lock); -#else - if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - assert(*rb->acl == RB_CLOSED); - - pthread_cleanup_push((void(*)(void *))pthread_mutex_unlock, - (void *) rb->lock); - - while (!shm_rbuff_empty(rb)) -#ifdef __APPLE__ - pthread_cond_wait(rb->del, rb->lock); -#else - if (pthread_cond_wait(rb->del, rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); -#endif - pthread_cleanup_pop(true); -} - -size_t shm_rbuff_queued(struct shm_rbuff * rb) -{ - size_t ret; - - assert(rb); - -#ifdef __APPLE__ - pthread_mutex_lock(rb->lock); +#if (defined (SHM_RBUFF_LOCKLESS) && \ + (defined(__GNUC__) || defined (__clang__))) +#include "shm_rbuff_ll.c" #else - if (pthread_mutex_lock(rb->lock) == EOWNERDEAD) - pthread_mutex_consistent(rb->lock); +#include "shm_rbuff_pthr.c" #endif - - ret = shm_rbuff_used(rb); - - pthread_mutex_unlock(rb->lock); - - return ret; -} -- cgit v1.2.3