From c9fb3c62896f4f918ab99b2e1ed2f6eff387c507 Mon Sep 17 00:00:00 2001 From: Jia He Date: Sun, 21 Jan 2018 20:41:27 -0800 Subject: [PATCH] ring: move code in a new header file Move the common part of rte_ring.h into rte_ring_generic.h. Move the memory barrier part into update_tail(). No functional changes here. Suggested-by: Jerin Jacob Suggested-by: Konstantin Ananyev Signed-off-by: Jia He Acked-by: Jerin Jacob Acked-by: Olivier Matz Acked-by: Hemant Agrawal --- lib/librte_eventdev/rte_event_ring.h | 6 +- lib/librte_ring/Makefile | 3 +- lib/librte_ring/rte_ring.h | 161 +------------------ lib/librte_ring/rte_ring_generic.h | 228 +++++++++++++++++++++++++++ 4 files changed, 236 insertions(+), 162 deletions(-) create mode 100644 lib/librte_ring/rte_ring_generic.h diff --git a/lib/librte_eventdev/rte_event_ring.h b/lib/librte_eventdev/rte_event_ring.h index 480d1d0c75..29d4228aba 100644 --- a/lib/librte_eventdev/rte_event_ring.h +++ b/lib/librte_eventdev/rte_event_ring.h @@ -98,9 +98,8 @@ rte_event_ring_enqueue_burst(struct rte_event_ring *r, goto end; ENQUEUE_PTRS(&r->r, &r[1], prod_head, events, n, struct rte_event); - rte_smp_wmb(); - update_tail(&r->r.prod, prod_head, prod_next, 1); + update_tail(&r->r.prod, prod_head, prod_next, 1, 1); end: if (free_space != NULL) *free_space = free_entries - n; @@ -140,9 +139,8 @@ rte_event_ring_dequeue_burst(struct rte_event_ring *r, goto end; DEQUEUE_PTRS(&r->r, &r[1], cons_head, events, n, struct rte_event); - rte_smp_rmb(); - update_tail(&r->r.cons, cons_head, cons_next, 1); + update_tail(&r->r.cons, cons_head, cons_next, 1, 0); end: if (available != NULL) diff --git a/lib/librte_ring/Makefile b/lib/librte_ring/Makefile index f5f0d35efe..281ffb718e 100644 --- a/lib/librte_ring/Makefile +++ b/lib/librte_ring/Makefile @@ -17,6 +17,7 @@ LIBABIVER := 1 SRCS-$(CONFIG_RTE_LIBRTE_RING) := rte_ring.c # install includes -SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include := rte_ring.h +SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include := rte_ring.h \ + rte_ring_generic.h include $(RTE_SDK)/mk/rte.lib.mk diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h index 7069d52e29..bc3756adce 100644 --- a/lib/librte_ring/rte_ring.h +++ b/lib/librte_ring/rte_ring.h @@ -357,91 +357,8 @@ 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; -} +/* Move common functions to generic file */ +#include "rte_ring_generic.h" /** * @internal Enqueue several objects on the ring @@ -477,83 +394,14 @@ __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; return n; } -/** - * @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 * @@ -588,9 +436,8 @@ __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) diff --git a/lib/librte_ring/rte_ring_generic.h b/lib/librte_ring/rte_ring_generic.h new file mode 100644 index 0000000000..8c3e65b0b4 --- /dev/null +++ b/lib/librte_ring/rte_ring_generic.h @@ -0,0 +1,228 @@ +/*- + * 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 + * + ************************************************************************** + * + * 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. + * + ***************************************************************************/ + +#ifndef _RTE_RING_GENERIC_H_ +#define _RTE_RING_GENERIC_H_ + +static __rte_always_inline void +update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val, + uint32_t single, uint32_t enqueue) +{ + if (enqueue) + rte_smp_wmb(); + else + rte_smp_rmb(); + /* + * 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; +} + +/** + * @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; +} + +#endif /* _RTE_RING_GENERIC_H_ */ -- 2.20.1