X-Git-Url: http://git.droids-corp.org/?p=dpdk.git;a=blobdiff_plain;f=lib%2Flibrte_ring%2Frte_ring.h;h=e92443813b5bf52e0e127907d1d0d29ae47a5f42;hp=751b5a86a98f496624ec1df6d43bccb8632ae8fc;hb=9bc2cbb007c0a3335c5582357ae9f6d37ea0b654;hpb=6f5f8ecce1b2d11abb758fe9a89f7a39a32cd6e9 diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h index 751b5a86a9..e92443813b 100644 --- a/lib/librte_ring/rte_ring.h +++ b/lib/librte_ring/rte_ring.h @@ -1,13 +1,13 @@ /*- * BSD LICENSE - * - * Copyright(c) 2010-2014 Intel Corporation. All rights reserved. + * + * 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 @@ -17,7 +17,7 @@ * * 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 @@ -91,6 +91,7 @@ extern "C" { #endif +#include #include #include #include @@ -99,31 +100,37 @@ extern "C" { #include #include #include +#include +#include + +#define RTE_TAILQ_RING_NAME "RTE_RING" enum rte_ring_queue_behavior { RTE_RING_QUEUE_FIXED = 0, /* Enq/Deq a fixed number of items from a ring */ - RTE_RING_QUEUE_VARIABLE /* Enq/Deq as many items a possible from ring */ + RTE_RING_QUEUE_VARIABLE /* Enq/Deq as many items as possible from ring */ }; -#ifdef RTE_LIBRTE_RING_DEBUG -/** - * A structure that stores the ring statistics (per-lcore). - */ -struct rte_ring_debug_stats { - uint64_t enq_success_bulk; /**< Successful enqueues number. */ - uint64_t enq_success_objs; /**< Objects successfully enqueued. */ - uint64_t enq_quota_bulk; /**< Successful enqueues above watermark. */ - uint64_t enq_quota_objs; /**< Objects enqueued above watermark. */ - uint64_t enq_fail_bulk; /**< Failed enqueues number. */ - uint64_t enq_fail_objs; /**< Objects that failed to be enqueued. */ - uint64_t deq_success_bulk; /**< Successful dequeues number. */ - uint64_t deq_success_objs; /**< Objects successfully dequeued. */ - uint64_t deq_fail_bulk; /**< Failed dequeues number. */ - uint64_t deq_fail_objs; /**< Objects that failed to be dequeued. */ -} __rte_cache_aligned; +#define RTE_RING_MZ_PREFIX "RG_" +/**< The maximum length of a ring name. */ +#define RTE_RING_NAMESIZE (RTE_MEMZONE_NAMESIZE - \ + sizeof(RTE_RING_MZ_PREFIX) + 1) + +struct rte_memzone; /* forward declaration, so as not to require memzone.h */ + +#if RTE_CACHE_LINE_SIZE < 128 +#define PROD_ALIGN (RTE_CACHE_LINE_SIZE * 2) +#define CONS_ALIGN (RTE_CACHE_LINE_SIZE * 2) +#else +#define PROD_ALIGN RTE_CACHE_LINE_SIZE +#define CONS_ALIGN RTE_CACHE_LINE_SIZE #endif -#define RTE_RING_NAMESIZE 32 /**< The maximum length of a ring name. */ +/* structure to hold a pair of head/tail values and other metadata */ +struct rte_ring_headtail { + volatile uint32_t head; /**< Prod/consumer head. */ + volatile uint32_t tail; /**< Prod/consumer tail. */ + uint32_t single; /**< True if single prod/cons */ +}; /** * An RTE ring structure. @@ -136,75 +143,110 @@ struct rte_ring_debug_stats { * a problem. */ struct rte_ring { - TAILQ_ENTRY(rte_ring) next; /**< Next in list. */ - - char name[RTE_RING_NAMESIZE]; /**< Name of the ring. */ - int flags; /**< Flags supplied at creation. */ + /* + * Note: this field kept the RTE_MEMZONE_NAMESIZE size due to ABI + * compatibility requirements, it could be changed to RTE_RING_NAMESIZE + * next time the ABI changes + */ + char name[RTE_MEMZONE_NAMESIZE] __rte_cache_aligned; /**< Name of the ring. */ + int flags; /**< Flags supplied at creation. */ + const struct rte_memzone *memzone; + /**< Memzone, if any, containing the rte_ring */ + uint32_t size; /**< Size of ring. */ + uint32_t mask; /**< Mask (size-1) of ring. */ + uint32_t capacity; /**< Usable size of ring */ /** Ring producer status. */ - struct prod { - uint32_t watermark; /**< Maximum items before EDQUOT. */ - uint32_t sp_enqueue; /**< True, if single producer. */ - uint32_t size; /**< Size of ring. */ - uint32_t mask; /**< Mask (size-1) of ring. */ - volatile uint32_t head; /**< Producer head. */ - volatile uint32_t tail; /**< Producer tail. */ - } prod __rte_cache_aligned; + struct rte_ring_headtail prod __rte_aligned(PROD_ALIGN); /** Ring consumer status. */ - struct cons { - uint32_t sc_dequeue; /**< True, if single consumer. */ - uint32_t size; /**< Size of the ring. */ - uint32_t mask; /**< Mask (size-1) of ring. */ - volatile uint32_t head; /**< Consumer head. */ - volatile uint32_t tail; /**< Consumer tail. */ -#ifdef RTE_RING_SPLIT_PROD_CONS - } cons __rte_cache_aligned; -#else - } cons; -#endif - -#ifdef RTE_LIBRTE_RING_DEBUG - struct rte_ring_debug_stats stats[RTE_MAX_LCORE]; -#endif - - void * ring[0] __rte_cache_aligned; /**< Memory space of ring starts here. - * not volatile so need to be careful - * about compiler re-ordering */ + struct rte_ring_headtail cons __rte_aligned(CONS_ALIGN); }; #define RING_F_SP_ENQ 0x0001 /**< The default enqueue is "single-producer". */ #define RING_F_SC_DEQ 0x0002 /**< The default dequeue is "single-consumer". */ -#define RTE_RING_QUOT_EXCEED (1 << 31) /**< Quota exceed for burst ops */ -#define RTE_RING_SZ_MASK (unsigned)(0x0fffffff) /**< Ring size mask */ +/** + * Ring is to hold exactly requested number of entries. + * Without this flag set, the ring size requested must be a power of 2, and the + * usable space will be that size - 1. With the flag, the requested size will + * be rounded up to the next power of two, but the usable space will be exactly + * that requested. Worst case, if a power-of-2 size is requested, half the + * ring space will be wasted. + */ +#define RING_F_EXACT_SZ 0x0004 +#define RTE_RING_SZ_MASK (0x7fffffffU) /**< Ring size mask */ + +/* @internal defines for passing to the enqueue dequeue worker functions */ +#define __IS_SP 1 +#define __IS_MP 0 +#define __IS_SC 1 +#define __IS_MC 0 /** - * @internal When debug is enabled, store ring statistics. + * Calculate the memory size needed for a ring + * + * This function returns the number of bytes needed for a ring, given + * the number of elements in it. This value is the sum of the size of + * the structure rte_ring and the size of the memory needed by the + * objects pointers. The value is aligned to a cache line size. + * + * @param count + * The number of elements in the ring (must be a power of 2). + * @return + * - The memory size needed for the ring on success. + * - -EINVAL if count is not a power of 2. + */ +ssize_t rte_ring_get_memsize(unsigned count); + +/** + * Initialize a ring structure. + * + * Initialize a ring structure in memory pointed by "r". The size of the + * memory area must be large enough to store the ring structure and the + * object table. It is advised to use rte_ring_get_memsize() to get the + * appropriate size. + * + * The ring size is set to *count*, which must be a power of two. Water + * marking is disabled by default. The real usable ring size is + * *count-1* instead of *count* to differentiate a free ring from an + * empty ring. + * + * The ring is not added in RTE_TAILQ_RING global list. Indeed, the + * memory given by the caller may not be shareable among dpdk + * processes. + * * @param r - * A pointer to the ring. + * The pointer to the ring structure followed by the objects table. * @param name - * The name of the statistics field to increment in the ring. - * @param n - * The number to add to the object-oriented statistics. + * The name of the ring. + * @param count + * The number of elements in the ring (must be a power of 2). + * @param flags + * An OR of the following: + * - RING_F_SP_ENQ: If this flag is set, the default behavior when + * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()`` + * is "single-producer". Otherwise, it is "multi-producers". + * - RING_F_SC_DEQ: If this flag is set, the default behavior when + * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()`` + * is "single-consumer". Otherwise, it is "multi-consumers". + * @return + * 0 on success, or a negative value on error. */ -#ifdef RTE_LIBRTE_RING_DEBUG -#define __RING_STAT_ADD(r, name, n) do { \ - unsigned __lcore_id = rte_lcore_id(); \ - r->stats[__lcore_id].name##_objs += n; \ - r->stats[__lcore_id].name##_bulk += 1; \ - } while(0) -#else -#define __RING_STAT_ADD(r, name, n) do {} while(0) -#endif +int rte_ring_init(struct rte_ring *r, const char *name, unsigned count, + unsigned flags); /** * Create a new ring named *name* in memory. * - * This function uses ``memzone_reserve()`` to allocate memory. Its size is - * set to *count*, which must be a power of two. Water marking is - * disabled by default. - * Note that the real usable ring size is *count-1* instead of - * *count*. + * This function uses ``memzone_reserve()`` to allocate memory. Then it + * calls rte_ring_init() to initialize an empty ring. + * + * The new ring size is set to *count*, which must be a power of + * two. Water marking is disabled by default. The real usable ring size + * is *count-1* instead of *count* to differentiate a free ring from an + * empty ring. + * + * The ring is added in RTE_TAILQ_RING list. * * @param name * The name of the ring. @@ -227,7 +269,6 @@ struct rte_ring { * rte_errno set appropriately. Possible errno values include: * - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure * - E_RTE_SECONDARY - function was called from a secondary process instance - * - E_RTE_NO_TAILQ - no tailq list could be got for the ring list * - EINVAL - count provided is not a power of 2 * - ENOSPC - the maximum number of memzones has already been allocated * - EEXIST - a memzone with the same name already exists @@ -235,189 +276,176 @@ struct rte_ring { */ struct rte_ring *rte_ring_create(const char *name, unsigned count, int socket_id, unsigned flags); - /** - * Change the high water mark. - * - * If *count* is 0, water marking is disabled. Otherwise, it is set to the - * *count* value. The *count* value must be greater than 0 and less - * than the ring size. - * - * This function can be called at any time (not necessarily at - * initialization). + * De-allocate all memory used by the ring. * * @param r - * A pointer to the ring structure. - * @param count - * The new water mark value. - * @return - * - 0: Success; water mark changed. - * - -EINVAL: Invalid water mark value. + * Ring to free */ -int rte_ring_set_water_mark(struct rte_ring *r, unsigned count); +void rte_ring_free(struct rte_ring *r); /** - * Dump the status of the ring to the console. + * Dump the status of the ring to a file. * + * @param f + * A pointer to a file for output * @param r * A pointer to the ring structure. */ -void rte_ring_dump(const struct rte_ring *r); +void rte_ring_dump(FILE *f, const struct rte_ring *r); -/* the actual enqueue of pointers on the ring. +/* the actual enqueue of pointers on the ring. * Placed here since identical code needed in both * single and multi producer enqueue functions */ -#define ENQUEUE_PTRS() do { \ - const uint32_t size = r->prod.size; \ - uint32_t idx = prod_head & mask; \ +#define ENQUEUE_PTRS(r, ring_start, prod_head, obj_table, n, obj_type) do { \ + unsigned int i; \ + const uint32_t size = (r)->size; \ + uint32_t idx = prod_head & (r)->mask; \ + obj_type *ring = (obj_type *)ring_start; \ if (likely(idx + n < size)) { \ for (i = 0; i < (n & ((~(unsigned)0x3))); i+=4, idx+=4) { \ - r->ring[idx] = obj_table[i]; \ - r->ring[idx+1] = obj_table[i+1]; \ - r->ring[idx+2] = obj_table[i+2]; \ - r->ring[idx+3] = obj_table[i+3]; \ + ring[idx] = obj_table[i]; \ + ring[idx+1] = obj_table[i+1]; \ + ring[idx+2] = obj_table[i+2]; \ + ring[idx+3] = obj_table[i+3]; \ } \ switch (n & 0x3) { \ - case 3: r->ring[idx++] = obj_table[i++]; \ - case 2: r->ring[idx++] = obj_table[i++]; \ - case 1: r->ring[idx++] = obj_table[i++]; \ + case 3: \ + ring[idx++] = obj_table[i++]; /* fallthrough */ \ + case 2: \ + ring[idx++] = obj_table[i++]; /* fallthrough */ \ + case 1: \ + ring[idx++] = obj_table[i++]; \ } \ } else { \ for (i = 0; idx < size; i++, idx++)\ - r->ring[idx] = obj_table[i]; \ + ring[idx] = obj_table[i]; \ for (idx = 0; i < n; i++, idx++) \ - r->ring[idx] = obj_table[i]; \ + ring[idx] = obj_table[i]; \ } \ -} while(0) +} while (0) -/* the actual copy of pointers on the ring to obj_table. +/* the actual copy of pointers on the ring to obj_table. * Placed here since identical code needed in both * single and multi consumer dequeue functions */ -#define DEQUEUE_PTRS() do { \ - uint32_t idx = cons_head & mask; \ - const uint32_t size = r->cons.size; \ +#define DEQUEUE_PTRS(r, ring_start, cons_head, obj_table, n, obj_type) do { \ + unsigned int i; \ + uint32_t idx = cons_head & (r)->mask; \ + const uint32_t size = (r)->size; \ + obj_type *ring = (obj_type *)ring_start; \ if (likely(idx + n < size)) { \ for (i = 0; i < (n & (~(unsigned)0x3)); i+=4, idx+=4) {\ - obj_table[i] = r->ring[idx]; \ - obj_table[i+1] = r->ring[idx+1]; \ - obj_table[i+2] = r->ring[idx+2]; \ - obj_table[i+3] = r->ring[idx+3]; \ + obj_table[i] = ring[idx]; \ + obj_table[i+1] = ring[idx+1]; \ + obj_table[i+2] = ring[idx+2]; \ + obj_table[i+3] = ring[idx+3]; \ } \ switch (n & 0x3) { \ - case 3: obj_table[i++] = r->ring[idx++]; \ - case 2: obj_table[i++] = r->ring[idx++]; \ - case 1: obj_table[i++] = r->ring[idx++]; \ + case 3: \ + obj_table[i++] = ring[idx++]; /* fallthrough */ \ + case 2: \ + obj_table[i++] = ring[idx++]; /* fallthrough */ \ + case 1: \ + obj_table[i++] = ring[idx++]; \ } \ } else { \ for (i = 0; idx < size; i++, idx++) \ - obj_table[i] = r->ring[idx]; \ + obj_table[i] = ring[idx]; \ for (idx = 0; i < n; i++, idx++) \ - obj_table[i] = r->ring[idx]; \ + obj_table[i] = ring[idx]; \ } \ } 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 Enqueue several objects on the ring (multi-producers safe). - * - * This function uses a "compare and set" instruction to move the - * producer index atomically. + * @internal This function updates the producer head for enqueue * * @param r - * A pointer to the ring structure. - * @param obj_table - * A pointer to a table of void * pointers (objects). + * A pointer to the ring structure + * @param is_sp + * Indicates whether multi-producer path is needed or not * @param n - * The number of objects to add in the ring from the obj_table. + * 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 a possible from 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 - * Depend on the behavior value - * if behavior = RTE_RING_QUEUE_FIXED - * - 0: Success; objects enqueue. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. - * - -ENOBUFS: Not enough room in the ring to enqueue, no object is enqueued. - * if behavior = RTE_RING_QUEUE_VARIABLE - * - n: Actual number of objects enqueued. + * Actual number of objects enqueued. + * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only. */ -static inline int __attribute__((always_inline)) -__rte_ring_mp_do_enqueue(struct rte_ring *r, void * const *obj_table, - unsigned n, enum rte_ring_queue_behavior behavior) +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) { - uint32_t prod_head, prod_next; - uint32_t cons_tail, free_entries; - const unsigned max = n; + const uint32_t capacity = r->capacity; + unsigned int max = n; int success; - unsigned i; - uint32_t mask = r->prod.mask; - int ret; - /* move prod.head atomically */ do { /* Reset n to the initial burst count */ n = max; - prod_head = r->prod.head; - cons_tail = r->cons.tail; - /* The subtraction is done between two unsigned 32bits value + *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 - * prod_head > cons_tail). So 'free_entries' is always between 0 - * and size(ring)-1. */ - free_entries = (mask + cons_tail - prod_head); + * *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)) { - if (behavior == RTE_RING_QUEUE_FIXED) { - __RING_STAT_ADD(r, enq_fail, n); - return -ENOBUFS; - } - else { - /* No free entry available */ - if (unlikely(free_entries == 0)) { - __RING_STAT_ADD(r, enq_fail, n); - return 0; - } - - n = free_entries; - } - } - - prod_next = prod_head + n; - success = rte_atomic32_cmpset(&r->prod.head, prod_head, - prod_next); + 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)); - - /* write entries in ring */ - ENQUEUE_PTRS(); - rte_compiler_barrier(); - - /* if we exceed the watermark */ - if (unlikely(((mask + 1) - free_entries + n) > r->prod.watermark)) { - ret = (behavior == RTE_RING_QUEUE_FIXED) ? -EDQUOT : - (int)(n | RTE_RING_QUOT_EXCEED); - __RING_STAT_ADD(r, enq_quota, n); - } - else { - ret = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : n; - __RING_STAT_ADD(r, enq_success, n); - } - - /* - * If there are other enqueues in progress that preceeded us, - * we need to wait for them to complete - */ - while (unlikely(r->prod.tail != prod_head)) - rte_pause(); - - r->prod.tail = prod_next; - return ret; + return n; } /** - * @internal Enqueue several objects on a ring (NOT multi-producers safe). + * @internal Enqueue several objects on the ring * - * @param r + * @param r * A pointer to the ring structure. * @param obj_table * A pointer to a table of void * pointers (objects). @@ -425,228 +453,148 @@ __rte_ring_mp_do_enqueue(struct rte_ring *r, void * const *obj_table, * The number of objects to add in the ring from the obj_table. * @param behavior * RTE_RING_QUEUE_FIXED: Enqueue a fixed number of items from a ring - * RTE_RING_QUEUE_VARIABLE: Enqueue as many items a possible from ring + * RTE_RING_QUEUE_VARIABLE: Enqueue as many items as possible from ring + * @param is_sp + * Indicates whether to use single producer or multi-producer head update + * @param free_space + * returns the amount of space after the enqueue operation has finished * @return - * Depend on the behavior value - * if behavior = RTE_RING_QUEUE_FIXED - * - 0: Success; objects enqueue. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. - * - -ENOBUFS: Not enough room in the ring to enqueue, no object is enqueued. - * if behavior = RTE_RING_QUEUE_VARIABLE - * - n: Actual number of objects enqueued. + * Actual number of objects enqueued. + * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only. */ -static inline int __attribute__((always_inline)) -__rte_ring_sp_do_enqueue(struct rte_ring *r, void * const *obj_table, - unsigned n, enum rte_ring_queue_behavior behavior) +static __rte_always_inline unsigned int +__rte_ring_do_enqueue(struct rte_ring *r, void * const *obj_table, + unsigned int n, enum rte_ring_queue_behavior behavior, + int is_sp, unsigned int *free_space) { - uint32_t prod_head, cons_tail; - uint32_t prod_next, free_entries; - unsigned i; - uint32_t mask = r->prod.mask; - int ret; - - prod_head = r->prod.head; - 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 - * prod_head > cons_tail). So 'free_entries' is always between 0 - * and size(ring)-1. */ - free_entries = mask + cons_tail - prod_head; - - /* check that we have enough room in ring */ - if (unlikely(n > free_entries)) { - if (behavior == RTE_RING_QUEUE_FIXED) { - __RING_STAT_ADD(r, enq_fail, n); - return -ENOBUFS; - } - else { - /* No free entry available */ - if (unlikely(free_entries == 0)) { - __RING_STAT_ADD(r, enq_fail, n); - return 0; - } - - n = free_entries; - } - } - - prod_next = prod_head + n; - r->prod.head = prod_next; - - /* write entries in ring */ - ENQUEUE_PTRS(); - rte_compiler_barrier(); - - /* if we exceed the watermark */ - if (unlikely(((mask + 1) - free_entries + n) > r->prod.watermark)) { - ret = (behavior == RTE_RING_QUEUE_FIXED) ? -EDQUOT : - (int)(n | RTE_RING_QUOT_EXCEED); - __RING_STAT_ADD(r, enq_quota, n); - } - else { - ret = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : n; - __RING_STAT_ADD(r, enq_success, n); - } - - r->prod.tail = prod_next; - return ret; + uint32_t prod_head, prod_next; + uint32_t free_entries; + + n = __rte_ring_move_prod_head(r, is_sp, n, behavior, + &prod_head, &prod_next, &free_entries); + if (n == 0) + 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); +end: + if (free_space != NULL) + *free_space = free_entries - n; + return n; } /** - * @internal Dequeue several objects from a ring (multi-consumers safe). When - * the request objects are more than the available objects, only dequeue the - * actual number of objects - * - * This function uses a "compare and set" instruction to move the - * consumer index atomically. + * @internal This function updates the consumer head for dequeue * * @param r - * A pointer to the ring structure. - * @param obj_table - * A pointer to a table of void * pointers (objects) that will be filled. + * A pointer to the ring structure + * @param is_sc + * Indicates whether multi-consumer path is needed or not * @param n - * The number of objects to dequeue from the ring to the obj_table. + * 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 a possible from 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 - * Depend on the behavior value - * if behavior = RTE_RING_QUEUE_FIXED - * - 0: Success; objects dequeued. - * - -ENOENT: Not enough entries in the ring to dequeue; no object is - * dequeued. - * if behavior = RTE_RING_QUEUE_VARIABLE - * - n: Actual number of objects dequeued. + * - Actual number of objects dequeued. + * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only. */ - -static inline int __attribute__((always_inline)) -__rte_ring_mc_do_dequeue(struct rte_ring *r, void **obj_table, - unsigned n, enum rte_ring_queue_behavior behavior) +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) { - uint32_t cons_head, prod_tail; - uint32_t cons_next, entries; - const unsigned max = n; + unsigned int max = n; int success; - unsigned i; - uint32_t mask = r->prod.mask; /* move cons.head atomically */ do { /* Restore n as it may change every loop */ n = max; - cons_head = r->cons.head; - prod_tail = r->prod.tail; + *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 - cons_head); + *entries = (prod_tail - *old_head); /* Set the actual entries for dequeue */ - if (n > entries) { - if (behavior == RTE_RING_QUEUE_FIXED) { - __RING_STAT_ADD(r, deq_fail, n); - return -ENOENT; - } - else { - if (unlikely(entries == 0)){ - __RING_STAT_ADD(r, deq_fail, n); - return 0; - } - - n = entries; - } - } - - cons_next = cons_head + n; - success = rte_atomic32_cmpset(&r->cons.head, cons_head, - cons_next); + 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)); - - /* copy in table */ - DEQUEUE_PTRS(); - rte_compiler_barrier(); - - /* - * If there are other dequeues in progress that preceded us, - * we need to wait for them to complete - */ - while (unlikely(r->cons.tail != cons_head)) - rte_pause(); - - __RING_STAT_ADD(r, deq_success, n); - r->cons.tail = cons_next; - - return behavior == RTE_RING_QUEUE_FIXED ? 0 : n; + return n; } /** - * @internal Dequeue several objects from a ring (NOT multi-consumers safe). - * When the request objects are more than the available objects, only dequeue - * the actual number of objects + * @internal Dequeue several objects from the ring * * @param r * A pointer to the ring structure. * @param obj_table - * A pointer to a table of void * pointers (objects) that will be filled. + * A pointer to a table of void * pointers (objects). * @param n - * The number of objects to dequeue from the ring to the obj_table. + * The number of objects to pull from the ring. * @param behavior * RTE_RING_QUEUE_FIXED: Dequeue a fixed number of items from a ring - * RTE_RING_QUEUE_VARIABLE: Dequeue as many items a possible from ring + * RTE_RING_QUEUE_VARIABLE: Dequeue as many items as possible from ring + * @param is_sc + * Indicates whether to use single consumer or multi-consumer head update + * @param available + * returns the number of remaining ring entries after the dequeue has finished * @return - * Depend on the behavior value - * if behavior = RTE_RING_QUEUE_FIXED - * - 0: Success; objects dequeued. - * - -ENOENT: Not enough entries in the ring to dequeue; no object is - * dequeued. - * if behavior = RTE_RING_QUEUE_VARIABLE - * - n: Actual number of objects dequeued. + * - Actual number of objects dequeued. + * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only. */ -static inline int __attribute__((always_inline)) -__rte_ring_sc_do_dequeue(struct rte_ring *r, void **obj_table, - unsigned n, enum rte_ring_queue_behavior behavior) +static __rte_always_inline unsigned int +__rte_ring_do_dequeue(struct rte_ring *r, void **obj_table, + unsigned int n, enum rte_ring_queue_behavior behavior, + int is_sc, unsigned int *available) { - uint32_t cons_head, prod_tail; - uint32_t cons_next, entries; - unsigned i; - uint32_t mask = r->prod.mask; - - cons_head = r->cons.head; - 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 - cons_head; - - if (n > entries) { - if (behavior == RTE_RING_QUEUE_FIXED) { - __RING_STAT_ADD(r, deq_fail, n); - return -ENOENT; - } - else { - if (unlikely(entries == 0)){ - __RING_STAT_ADD(r, deq_fail, n); - return 0; - } - - n = entries; - } - } - - cons_next = cons_head + n; - r->cons.head = cons_next; - - /* copy in table */ - DEQUEUE_PTRS(); - rte_compiler_barrier(); - - __RING_STAT_ADD(r, deq_success, n); - r->cons.tail = cons_next; - return behavior == RTE_RING_QUEUE_FIXED ? 0 : n; + uint32_t cons_head, cons_next; + uint32_t entries; + + n = __rte_ring_move_cons_head(r, is_sc, n, behavior, + &cons_head, &cons_next, &entries); + if (n == 0) + 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); + +end: + if (available != NULL) + *available = entries - n; + return n; } /** @@ -661,17 +609,18 @@ __rte_ring_sc_do_dequeue(struct rte_ring *r, void **obj_table, * A pointer to a table of void * pointers (objects). * @param n * The number of objects to add in the ring from the obj_table. + * @param free_space + * if non-NULL, returns the amount of space in the ring after the + * enqueue operation has finished. * @return - * - 0: Success; objects enqueue. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. - * - -ENOBUFS: Not enough room in the ring to enqueue, no object is enqueued. + * The number of objects enqueued, either 0 or n */ -static inline int __attribute__((always_inline)) +static __rte_always_inline unsigned int rte_ring_mp_enqueue_bulk(struct rte_ring *r, void * const *obj_table, - unsigned n) + unsigned int n, unsigned int *free_space) { - return __rte_ring_mp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_FIXED); + return __rte_ring_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_FIXED, + __IS_MP, free_space); } /** @@ -683,17 +632,18 @@ rte_ring_mp_enqueue_bulk(struct rte_ring *r, void * const *obj_table, * A pointer to a table of void * pointers (objects). * @param n * The number of objects to add in the ring from the obj_table. + * @param free_space + * if non-NULL, returns the amount of space in the ring after the + * enqueue operation has finished. * @return - * - 0: Success; objects enqueued. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. - * - -ENOBUFS: Not enough room in the ring to enqueue; no object is enqueued. + * The number of objects enqueued, either 0 or n */ -static inline int __attribute__((always_inline)) +static __rte_always_inline unsigned int rte_ring_sp_enqueue_bulk(struct rte_ring *r, void * const *obj_table, - unsigned n) + unsigned int n, unsigned int *free_space) { - return __rte_ring_sp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_FIXED); + return __rte_ring_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_FIXED, + __IS_SP, free_space); } /** @@ -709,20 +659,18 @@ rte_ring_sp_enqueue_bulk(struct rte_ring *r, void * const *obj_table, * A pointer to a table of void * pointers (objects). * @param n * The number of objects to add in the ring from the obj_table. + * @param free_space + * if non-NULL, returns the amount of space in the ring after the + * enqueue operation has finished. * @return - * - 0: Success; objects enqueued. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. - * - -ENOBUFS: Not enough room in the ring to enqueue; no object is enqueued. + * The number of objects enqueued, either 0 or n */ -static inline int __attribute__((always_inline)) +static __rte_always_inline unsigned int rte_ring_enqueue_bulk(struct rte_ring *r, void * const *obj_table, - unsigned n) + unsigned int n, unsigned int *free_space) { - if (r->prod.sp_enqueue) - return rte_ring_sp_enqueue_bulk(r, obj_table, n); - else - return rte_ring_mp_enqueue_bulk(r, obj_table, n); + return __rte_ring_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_FIXED, + r->prod.single, free_space); } /** @@ -737,14 +685,12 @@ rte_ring_enqueue_bulk(struct rte_ring *r, void * const *obj_table, * A pointer to the object to be added. * @return * - 0: Success; objects enqueued. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. * - -ENOBUFS: Not enough room in the ring to enqueue; no object is enqueued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline int rte_ring_mp_enqueue(struct rte_ring *r, void *obj) { - return rte_ring_mp_enqueue_bulk(r, &obj, 1); + return rte_ring_mp_enqueue_bulk(r, &obj, 1, NULL) ? 0 : -ENOBUFS; } /** @@ -756,14 +702,12 @@ rte_ring_mp_enqueue(struct rte_ring *r, void *obj) * A pointer to the object to be added. * @return * - 0: Success; objects enqueued. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. * - -ENOBUFS: Not enough room in the ring to enqueue; no object is enqueued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline int rte_ring_sp_enqueue(struct rte_ring *r, void *obj) { - return rte_ring_sp_enqueue_bulk(r, &obj, 1); + return rte_ring_sp_enqueue_bulk(r, &obj, 1, NULL) ? 0 : -ENOBUFS; } /** @@ -779,17 +723,12 @@ rte_ring_sp_enqueue(struct rte_ring *r, void *obj) * A pointer to the object to be added. * @return * - 0: Success; objects enqueued. - * - -EDQUOT: Quota exceeded. The objects have been enqueued, but the - * high water mark is exceeded. * - -ENOBUFS: Not enough room in the ring to enqueue; no object is enqueued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline int rte_ring_enqueue(struct rte_ring *r, void *obj) { - if (r->prod.sp_enqueue) - return rte_ring_sp_enqueue(r, obj); - else - return rte_ring_mp_enqueue(r, obj); + return rte_ring_enqueue_bulk(r, &obj, 1, NULL) ? 0 : -ENOBUFS; } /** @@ -804,15 +743,18 @@ rte_ring_enqueue(struct rte_ring *r, void *obj) * A pointer to a table of void * pointers (objects) that will be filled. * @param n * The number of objects to dequeue from the ring to the obj_table. + * @param available + * If non-NULL, returns the number of remaining ring entries after the + * dequeue has finished. * @return - * - 0: Success; objects dequeued. - * - -ENOENT: Not enough entries in the ring to dequeue; no object is - * dequeued. + * The number of objects dequeued, either 0 or n */ -static inline int __attribute__((always_inline)) -rte_ring_mc_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n) +static __rte_always_inline unsigned int +rte_ring_mc_dequeue_bulk(struct rte_ring *r, void **obj_table, + unsigned int n, unsigned int *available) { - return __rte_ring_mc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED); + return __rte_ring_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED, + __IS_MC, available); } /** @@ -825,15 +767,18 @@ rte_ring_mc_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n) * @param n * The number of objects to dequeue from the ring to the obj_table, * must be strictly positive. + * @param available + * If non-NULL, returns the number of remaining ring entries after the + * dequeue has finished. * @return - * - 0: Success; objects dequeued. - * - -ENOENT: Not enough entries in the ring to dequeue; no object is - * dequeued. + * The number of objects dequeued, either 0 or n */ -static inline int __attribute__((always_inline)) -rte_ring_sc_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n) +static __rte_always_inline unsigned int +rte_ring_sc_dequeue_bulk(struct rte_ring *r, void **obj_table, + unsigned int n, unsigned int *available) { - return __rte_ring_sc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED); + return __rte_ring_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED, + __IS_SC, available); } /** @@ -849,18 +794,18 @@ rte_ring_sc_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n) * A pointer to a table of void * pointers (objects) that will be filled. * @param n * The number of objects to dequeue from the ring to the obj_table. + * @param available + * If non-NULL, returns the number of remaining ring entries after the + * dequeue has finished. * @return - * - 0: Success; objects dequeued. - * - -ENOENT: Not enough entries in the ring to dequeue, no object is - * dequeued. + * The number of objects dequeued, either 0 or n */ -static inline int __attribute__((always_inline)) -rte_ring_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n) +static __rte_always_inline unsigned int +rte_ring_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned int n, + unsigned int *available) { - if (r->cons.sc_dequeue) - return rte_ring_sc_dequeue_bulk(r, obj_table, n); - else - return rte_ring_mc_dequeue_bulk(r, obj_table, n); + return __rte_ring_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED, + r->cons.single, available); } /** @@ -878,10 +823,10 @@ rte_ring_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n) * - -ENOENT: Not enough entries in the ring to dequeue; no object is * dequeued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline int rte_ring_mc_dequeue(struct rte_ring *r, void **obj_p) { - return rte_ring_mc_dequeue_bulk(r, obj_p, 1); + return rte_ring_mc_dequeue_bulk(r, obj_p, 1, NULL) ? 0 : -ENOENT; } /** @@ -896,10 +841,10 @@ rte_ring_mc_dequeue(struct rte_ring *r, void **obj_p) * - -ENOENT: Not enough entries in the ring to dequeue, no object is * dequeued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline int rte_ring_sc_dequeue(struct rte_ring *r, void **obj_p) { - return rte_ring_sc_dequeue_bulk(r, obj_p, 1); + return rte_ring_sc_dequeue_bulk(r, obj_p, 1, NULL) ? 0 : -ENOENT; } /** @@ -918,13 +863,41 @@ rte_ring_sc_dequeue(struct rte_ring *r, void **obj_p) * - -ENOENT: Not enough entries in the ring to dequeue, no object is * dequeued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline int rte_ring_dequeue(struct rte_ring *r, void **obj_p) { - if (r->cons.sc_dequeue) - return rte_ring_sc_dequeue(r, obj_p); - else - return rte_ring_mc_dequeue(r, obj_p); + return rte_ring_dequeue_bulk(r, obj_p, 1, NULL) ? 0 : -ENOENT; +} + +/** + * Return the number of entries in a ring. + * + * @param r + * A pointer to the ring structure. + * @return + * The number of entries in the ring. + */ +static inline unsigned +rte_ring_count(const struct rte_ring *r) +{ + uint32_t prod_tail = r->prod.tail; + uint32_t cons_tail = r->cons.tail; + uint32_t count = (prod_tail - cons_tail) & r->mask; + return (count > r->capacity) ? r->capacity : count; +} + +/** + * Return the number of free entries in a ring. + * + * @param r + * A pointer to the ring structure. + * @return + * The number of free entries in the ring. + */ +static inline unsigned +rte_ring_free_count(const struct rte_ring *r) +{ + return r->capacity - rte_ring_count(r); } /** @@ -939,9 +912,7 @@ rte_ring_dequeue(struct rte_ring *r, void **obj_p) static inline int rte_ring_full(const struct rte_ring *r) { - uint32_t prod_tail = r->prod.tail; - uint32_t cons_tail = r->cons.tail; - return (((cons_tail - prod_tail - 1) & r->prod.mask) == 0); + return rte_ring_free_count(r) == 0; } /** @@ -956,47 +927,46 @@ rte_ring_full(const struct rte_ring *r) static inline int rte_ring_empty(const struct rte_ring *r) { - uint32_t prod_tail = r->prod.tail; - uint32_t cons_tail = r->cons.tail; - return !!(cons_tail == prod_tail); + return rte_ring_count(r) == 0; } /** - * Return the number of entries in a ring. + * Return the size of the ring. * * @param r * A pointer to the ring structure. * @return - * The number of entries in the ring. + * The size of the data store used by the ring. + * NOTE: this is not the same as the usable space in the ring. To query that + * use ``rte_ring_get_capacity()``. */ -static inline unsigned -rte_ring_count(const struct rte_ring *r) +static inline unsigned int +rte_ring_get_size(const struct rte_ring *r) { - uint32_t prod_tail = r->prod.tail; - uint32_t cons_tail = r->cons.tail; - return ((prod_tail - cons_tail) & r->prod.mask); + return r->size; } /** - * Return the number of free entries in a ring. + * Return the number of elements which can be stored in the ring. * * @param r * A pointer to the ring structure. * @return - * The number of free entries in the ring. + * The usable size of the ring. */ -static inline unsigned -rte_ring_free_count(const struct rte_ring *r) +static inline unsigned int +rte_ring_get_capacity(const struct rte_ring *r) { - uint32_t prod_tail = r->prod.tail; - uint32_t cons_tail = r->cons.tail; - return ((cons_tail - prod_tail - 1) & r->prod.mask); + return r->capacity; } /** * Dump the status of all rings on the console + * + * @param f + * A pointer to a file for output */ -void rte_ring_list_dump(void); +void rte_ring_list_dump(FILE *f); /** * Search a ring from its name @@ -1022,14 +992,18 @@ struct rte_ring *rte_ring_lookup(const char *name); * A pointer to a table of void * pointers (objects). * @param n * The number of objects to add in the ring from the obj_table. + * @param free_space + * if non-NULL, returns the amount of space in the ring after the + * enqueue operation has finished. * @return * - n: Actual number of objects enqueued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline unsigned rte_ring_mp_enqueue_burst(struct rte_ring *r, void * const *obj_table, - unsigned n) + unsigned int n, unsigned int *free_space) { - return __rte_ring_mp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE); + return __rte_ring_do_enqueue(r, obj_table, n, + RTE_RING_QUEUE_VARIABLE, __IS_MP, free_space); } /** @@ -1041,14 +1015,18 @@ rte_ring_mp_enqueue_burst(struct rte_ring *r, void * const *obj_table, * A pointer to a table of void * pointers (objects). * @param n * The number of objects to add in the ring from the obj_table. + * @param free_space + * if non-NULL, returns the amount of space in the ring after the + * enqueue operation has finished. * @return * - n: Actual number of objects enqueued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline unsigned rte_ring_sp_enqueue_burst(struct rte_ring *r, void * const *obj_table, - unsigned n) + unsigned int n, unsigned int *free_space) { - return __rte_ring_sp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE); + return __rte_ring_do_enqueue(r, obj_table, n, + RTE_RING_QUEUE_VARIABLE, __IS_SP, free_space); } /** @@ -1064,17 +1042,18 @@ rte_ring_sp_enqueue_burst(struct rte_ring *r, void * const *obj_table, * A pointer to a table of void * pointers (objects). * @param n * The number of objects to add in the ring from the obj_table. + * @param free_space + * if non-NULL, returns the amount of space in the ring after the + * enqueue operation has finished. * @return * - n: Actual number of objects enqueued. */ -static inline int __attribute__((always_inline)) +static __rte_always_inline unsigned rte_ring_enqueue_burst(struct rte_ring *r, void * const *obj_table, - unsigned n) + unsigned int n, unsigned int *free_space) { - if (r->prod.sp_enqueue) - return rte_ring_sp_enqueue_burst(r, obj_table, n); - else - return rte_ring_mp_enqueue_burst(r, obj_table, n); + return __rte_ring_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE, + r->prod.single, free_space); } /** @@ -1091,13 +1070,18 @@ rte_ring_enqueue_burst(struct rte_ring *r, void * const *obj_table, * A pointer to a table of void * pointers (objects) that will be filled. * @param n * The number of objects to dequeue from the ring to the obj_table. + * @param available + * If non-NULL, returns the number of remaining ring entries after the + * dequeue has finished. * @return * - n: Actual number of objects dequeued, 0 if ring is empty */ -static inline int __attribute__((always_inline)) -rte_ring_mc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) +static __rte_always_inline unsigned +rte_ring_mc_dequeue_burst(struct rte_ring *r, void **obj_table, + unsigned int n, unsigned int *available) { - return __rte_ring_mc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE); + return __rte_ring_do_dequeue(r, obj_table, n, + RTE_RING_QUEUE_VARIABLE, __IS_MC, available); } /** @@ -1111,13 +1095,18 @@ rte_ring_mc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) * A pointer to a table of void * pointers (objects) that will be filled. * @param n * The number of objects to dequeue from the ring to the obj_table. + * @param available + * If non-NULL, returns the number of remaining ring entries after the + * dequeue has finished. * @return * - n: Actual number of objects dequeued, 0 if ring is empty */ -static inline int __attribute__((always_inline)) -rte_ring_sc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) +static __rte_always_inline unsigned +rte_ring_sc_dequeue_burst(struct rte_ring *r, void **obj_table, + unsigned int n, unsigned int *available) { - return __rte_ring_sc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE); + return __rte_ring_do_dequeue(r, obj_table, n, + RTE_RING_QUEUE_VARIABLE, __IS_SC, available); } /** @@ -1133,16 +1122,19 @@ rte_ring_sc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) * A pointer to a table of void * pointers (objects) that will be filled. * @param n * The number of objects to dequeue from the ring to the obj_table. + * @param available + * If non-NULL, returns the number of remaining ring entries after the + * dequeue has finished. * @return - * - Number of objects dequeued, or a negative error code on error + * - Number of objects dequeued */ -static inline int __attribute__((always_inline)) -rte_ring_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) +static __rte_always_inline unsigned +rte_ring_dequeue_burst(struct rte_ring *r, void **obj_table, + unsigned int n, unsigned int *available) { - if (r->cons.sc_dequeue) - return rte_ring_sc_dequeue_burst(r, obj_table, n); - else - return rte_ring_mc_dequeue_burst(r, obj_table, n); + return __rte_ring_do_dequeue(r, obj_table, n, + RTE_RING_QUEUE_VARIABLE, + r->cons.single, available); } #ifdef __cplusplus