lib: Lockless implementation of the rbuff

1 files changed, 4 insertions, 404 deletions

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 <[email protected]>
- *    Sander Vrijders   <[email protected]>
- *
- * 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 <ouroboros/config.h>
-#include <ouroboros/shm_rbuff.h>
-#include <ouroboros/lockfile.h>
-#include <ouroboros/time_utils.h>
-#include <ouroboros/errno.h>
-
-#include <pthread.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <unistd.h>
-#include <signal.h>
-#include <sys/stat.h>
-#include <assert.h>
-#include <stdbool.h>
-
-#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;
-}