From 97f17497d162afdb82c8704bf097f0fee3724b2e Mon Sep 17 00:00:00 2001 From: "C.J. Collier" Date: Tue, 14 Jun 2016 07:50:17 -0700 Subject: Imported Upstream version 16.04 Change-Id: I77eadcd8538a9122e4773cbe55b24033dc451757 Signed-off-by: C.J. Collier --- examples/performance-thread/common/lthread_mutex.c | 254 +++++++++++++++++++++ 1 file changed, 254 insertions(+) create mode 100644 examples/performance-thread/common/lthread_mutex.c (limited to 'examples/performance-thread/common/lthread_mutex.c') diff --git a/examples/performance-thread/common/lthread_mutex.c b/examples/performance-thread/common/lthread_mutex.c new file mode 100644 index 00000000..af8b82d2 --- /dev/null +++ b/examples/performance-thread/common/lthread_mutex.c @@ -0,0 +1,254 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2015 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include "lthread_api.h" +#include "lthread_int.h" +#include "lthread_mutex.h" +#include "lthread_sched.h" +#include "lthread_queue.h" +#include "lthread_objcache.h" +#include "lthread_diag.h" + +/* + * Create a mutex + */ +int +lthread_mutex_init(char *name, struct lthread_mutex **mutex, + __rte_unused const struct lthread_mutexattr *attr) +{ + struct lthread_mutex *m; + + if (mutex == NULL) + return POSIX_ERRNO(EINVAL); + + + m = _lthread_objcache_alloc((THIS_SCHED)->mutex_cache); + if (m == NULL) + return POSIX_ERRNO(EAGAIN); + + m->blocked = _lthread_queue_create("blocked queue"); + if (m->blocked == NULL) { + _lthread_objcache_free((THIS_SCHED)->mutex_cache, m); + return POSIX_ERRNO(EAGAIN); + } + + if (name == NULL) + strncpy(m->name, "no name", sizeof(m->name)); + else + strncpy(m->name, name, sizeof(m->name)); + m->name[sizeof(m->name)-1] = 0; + + m->root_sched = THIS_SCHED; + m->owner = NULL; + + rte_atomic64_init(&m->count); + + DIAG_CREATE_EVENT(m, LT_DIAG_MUTEX_CREATE); + /* success */ + (*mutex) = m; + return 0; +} + +/* + * Destroy a mutex + */ +int lthread_mutex_destroy(struct lthread_mutex *m) +{ + if ((m == NULL) || (m->blocked == NULL)) { + DIAG_EVENT(m, LT_DIAG_MUTEX_DESTROY, m, POSIX_ERRNO(EINVAL)); + return POSIX_ERRNO(EINVAL); + } + + if (m->owner == NULL) { + /* try to delete the blocked queue */ + if (_lthread_queue_destroy(m->blocked) < 0) { + DIAG_EVENT(m, LT_DIAG_MUTEX_DESTROY, + m, POSIX_ERRNO(EBUSY)); + return POSIX_ERRNO(EBUSY); + } + + /* free the mutex to cache */ + _lthread_objcache_free(m->root_sched->mutex_cache, m); + DIAG_EVENT(m, LT_DIAG_MUTEX_DESTROY, m, 0); + return 0; + } + /* can't do its still in use */ + DIAG_EVENT(m, LT_DIAG_MUTEX_DESTROY, m, POSIX_ERRNO(EBUSY)); + return POSIX_ERRNO(EBUSY); +} + +/* + * Try to obtain a mutex + */ +int lthread_mutex_lock(struct lthread_mutex *m) +{ + struct lthread *lt = THIS_LTHREAD; + + if ((m == NULL) || (m->blocked == NULL)) { + DIAG_EVENT(m, LT_DIAG_MUTEX_LOCK, m, POSIX_ERRNO(EINVAL)); + return POSIX_ERRNO(EINVAL); + } + + /* allow no recursion */ + if (m->owner == lt) { + DIAG_EVENT(m, LT_DIAG_MUTEX_LOCK, m, POSIX_ERRNO(EDEADLK)); + return POSIX_ERRNO(EDEADLK); + } + + for (;;) { + rte_atomic64_inc(&m->count); + do { + if (rte_atomic64_cmpset + ((uint64_t *) &m->owner, 0, (uint64_t) lt)) { + /* happy days, we got the lock */ + DIAG_EVENT(m, LT_DIAG_MUTEX_LOCK, m, 0); + return 0; + } + /* spin due to race with unlock when + * nothing was blocked + */ + } while ((rte_atomic64_read(&m->count) == 1) && + (m->owner == NULL)); + + /* queue the current thread in the blocked queue + * we defer this to after we return to the scheduler + * to ensure that the current thread context is saved + * before unlock could result in it being dequeued and + * resumed + */ + DIAG_EVENT(m, LT_DIAG_MUTEX_BLOCKED, m, lt); + lt->pending_wr_queue = m->blocked; + /* now relinquish cpu */ + _suspend(); + /* resumed, must loop and compete for the lock again */ + } + LTHREAD_ASSERT(0); + return 0; +} + +/* try to lock a mutex but dont block */ +int lthread_mutex_trylock(struct lthread_mutex *m) +{ + struct lthread *lt = THIS_LTHREAD; + + if ((m == NULL) || (m->blocked == NULL)) { + DIAG_EVENT(m, LT_DIAG_MUTEX_TRYLOCK, m, POSIX_ERRNO(EINVAL)); + return POSIX_ERRNO(EINVAL); + } + + if (m->owner == lt) { + /* no recursion */ + DIAG_EVENT(m, LT_DIAG_MUTEX_TRYLOCK, m, POSIX_ERRNO(EDEADLK)); + return POSIX_ERRNO(EDEADLK); + } + + rte_atomic64_inc(&m->count); + if (rte_atomic64_cmpset + ((uint64_t *) &m->owner, (uint64_t) NULL, (uint64_t) lt)) { + /* got the lock */ + DIAG_EVENT(m, LT_DIAG_MUTEX_TRYLOCK, m, 0); + return 0; + } + + /* failed so return busy */ + rte_atomic64_dec(&m->count); + DIAG_EVENT(m, LT_DIAG_MUTEX_TRYLOCK, m, POSIX_ERRNO(EBUSY)); + return POSIX_ERRNO(EBUSY); +} + +/* + * Unlock a mutex + */ +int lthread_mutex_unlock(struct lthread_mutex *m) +{ + struct lthread *lt = THIS_LTHREAD; + struct lthread *unblocked; + + if ((m == NULL) || (m->blocked == NULL)) { + DIAG_EVENT(m, LT_DIAG_MUTEX_UNLOCKED, m, POSIX_ERRNO(EINVAL)); + return POSIX_ERRNO(EINVAL); + } + + /* fail if its owned */ + if (m->owner != lt || m->owner == NULL) { + DIAG_EVENT(m, LT_DIAG_MUTEX_UNLOCKED, m, POSIX_ERRNO(EPERM)); + return POSIX_ERRNO(EPERM); + } + + rte_atomic64_dec(&m->count); + /* if there are blocked threads then make one ready */ + while (rte_atomic64_read(&m->count) > 0) { + unblocked = _lthread_queue_remove(m->blocked); + + if (unblocked != NULL) { + rte_atomic64_dec(&m->count); + DIAG_EVENT(m, LT_DIAG_MUTEX_UNLOCKED, m, unblocked); + LTHREAD_ASSERT(unblocked->sched != NULL); + _ready_queue_insert((struct lthread_sched *) + unblocked->sched, unblocked); + break; + } + } + /* release the lock */ + m->owner = NULL; + return 0; +} + +/* + * return the diagnostic ref val stored in a mutex + */ +uint64_t +lthread_mutex_diag_ref(struct lthread_mutex *m) +{ + if (m == NULL) + return 0; + return m->diag_ref; +} -- cgit 1.2.3-korg