diff options
Diffstat (limited to 'lib/librte_ring/rte_ring.h')
| -rw-r--r-- | lib/librte_ring/rte_ring.h | 240 |
1 files changed, 22 insertions, 218 deletions
diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h index e9244381..253cdc96 100644 --- a/lib/librte_ring/rte_ring.h +++ b/lib/librte_ring/rte_ring.h @@ -1,67 +1,11 @@ -/*- - * BSD LICENSE - * - * Copyright(c) 2010-2017 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. - */ - -/* - * Derived from FreeBSD's bufring.h - * - ************************************************************************** +/* SPDX-License-Identifier: BSD-3-Clause * + * Copyright (c) 2010-2017 Intel Corporation * Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are met: - * - * 1. Redistributions of source code must retain the above copyright notice, - * this list of conditions and the following disclaimer. - * - * 2. The name of Kip Macy nor the names of other - * 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. - * - ***************************************************************************/ + * Derived from FreeBSD's bufring.h + * Used as BSD-3 Licensed with permission from Kip Macy. + */ #ifndef _RTE_RING_H_ #define _RTE_RING_H_ @@ -96,6 +40,7 @@ extern "C" { #include <sys/queue.h> #include <errno.h> #include <rte_common.h> +#include <rte_config.h> #include <rte_memory.h> #include <rte_lcore.h> #include <rte_atomic.h> @@ -356,91 +301,20 @@ void rte_ring_dump(FILE *f, const struct rte_ring *r); } \ } while (0) -static __rte_always_inline void -update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val, - uint32_t single) -{ - /* - * If there are other enqueues/dequeues in progress that preceded us, - * we need to wait for them to complete - */ - if (!single) - while (unlikely(ht->tail != old_val)) - rte_pause(); - - ht->tail = new_val; -} - -/** - * @internal This function updates the producer head for enqueue - * - * @param r - * A pointer to the ring structure - * @param is_sp - * Indicates whether multi-producer path is needed or not - * @param n - * The number of elements we will want to enqueue, i.e. how far should the - * head be moved - * @param behavior - * RTE_RING_QUEUE_FIXED: Enqueue a fixed number of items from a ring - * RTE_RING_QUEUE_VARIABLE: Enqueue as many items as possible from ring - * @param old_head - * Returns head value as it was before the move, i.e. where enqueue starts - * @param new_head - * Returns the current/new head value i.e. where enqueue finishes - * @param free_entries - * Returns the amount of free space in the ring BEFORE head was moved - * @return - * Actual number of objects enqueued. - * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only. - */ -static __rte_always_inline unsigned int -__rte_ring_move_prod_head(struct rte_ring *r, int is_sp, - unsigned int n, enum rte_ring_queue_behavior behavior, - uint32_t *old_head, uint32_t *new_head, - uint32_t *free_entries) -{ - const uint32_t capacity = r->capacity; - unsigned int max = n; - int success; - - do { - /* Reset n to the initial burst count */ - n = max; - - *old_head = r->prod.head; - - /* add rmb barrier to avoid load/load reorder in weak - * memory model. It is noop on x86 - */ - rte_smp_rmb(); - - const uint32_t cons_tail = r->cons.tail; - /* - * The subtraction is done between two unsigned 32bits value - * (the result is always modulo 32 bits even if we have - * *old_head > cons_tail). So 'free_entries' is always between 0 - * and capacity (which is < size). - */ - *free_entries = (capacity + cons_tail - *old_head); - - /* check that we have enough room in ring */ - if (unlikely(n > *free_entries)) - n = (behavior == RTE_RING_QUEUE_FIXED) ? - 0 : *free_entries; - - if (n == 0) - return 0; - - *new_head = *old_head + n; - if (is_sp) - r->prod.head = *new_head, success = 1; - else - success = rte_atomic32_cmpset(&r->prod.head, - *old_head, *new_head); - } while (unlikely(success == 0)); - return n; -} +/* Between load and load. there might be cpu reorder in weak model + * (powerpc/arm). + * There are 2 choices for the users + * 1.use rmb() memory barrier + * 2.use one-direcion load_acquire/store_release barrier,defined by + * CONFIG_RTE_RING_USE_C11_MEM_MODEL=y + * It depends on performance test results. + * By default, move common functions to rte_ring_generic.h + */ +#ifdef RTE_RING_USE_C11_MEM_MODEL +#include "rte_ring_c11_mem.h" +#else +#include "rte_ring_generic.h" +#endif /** * @internal Enqueue several objects on the ring @@ -476,9 +350,8 @@ __rte_ring_do_enqueue(struct rte_ring *r, void * const *obj_table, goto end; ENQUEUE_PTRS(r, &r[1], prod_head, obj_table, n, void *); - rte_smp_wmb(); - update_tail(&r->prod, prod_head, prod_next, is_sp); + update_tail(&r->prod, prod_head, prod_next, is_sp, 1); end: if (free_space != NULL) *free_space = free_entries - n; @@ -486,74 +359,6 @@ end: } /** - * @internal This function updates the consumer head for dequeue - * - * @param r - * A pointer to the ring structure - * @param is_sc - * Indicates whether multi-consumer path is needed or not - * @param n - * The number of elements we will want to enqueue, i.e. how far should the - * head be moved - * @param behavior - * RTE_RING_QUEUE_FIXED: Dequeue a fixed number of items from a ring - * RTE_RING_QUEUE_VARIABLE: Dequeue as many items as possible from ring - * @param old_head - * Returns head value as it was before the move, i.e. where dequeue starts - * @param new_head - * Returns the current/new head value i.e. where dequeue finishes - * @param entries - * Returns the number of entries in the ring BEFORE head was moved - * @return - * - Actual number of objects dequeued. - * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only. - */ -static __rte_always_inline unsigned int -__rte_ring_move_cons_head(struct rte_ring *r, int is_sc, - unsigned int n, enum rte_ring_queue_behavior behavior, - uint32_t *old_head, uint32_t *new_head, - uint32_t *entries) -{ - unsigned int max = n; - int success; - - /* move cons.head atomically */ - do { - /* Restore n as it may change every loop */ - n = max; - - *old_head = r->cons.head; - - /* add rmb barrier to avoid load/load reorder in weak - * memory model. It is noop on x86 - */ - rte_smp_rmb(); - - const uint32_t prod_tail = r->prod.tail; - /* The subtraction is done between two unsigned 32bits value - * (the result is always modulo 32 bits even if we have - * cons_head > prod_tail). So 'entries' is always between 0 - * and size(ring)-1. */ - *entries = (prod_tail - *old_head); - - /* Set the actual entries for dequeue */ - if (n > *entries) - n = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : *entries; - - if (unlikely(n == 0)) - return 0; - - *new_head = *old_head + n; - if (is_sc) - r->cons.head = *new_head, success = 1; - else - success = rte_atomic32_cmpset(&r->cons.head, *old_head, - *new_head); - } while (unlikely(success == 0)); - return n; -} - -/** * @internal Dequeue several objects from the ring * * @param r @@ -587,9 +392,8 @@ __rte_ring_do_dequeue(struct rte_ring *r, void **obj_table, goto end; DEQUEUE_PTRS(r, &r[1], cons_head, obj_table, n, void *); - rte_smp_rmb(); - update_tail(&r->cons, cons_head, cons_next, is_sc); + update_tail(&r->cons, cons_head, cons_next, is_sc, 0); end: if (available != NULL) |