diff options
Diffstat (limited to 'lib/librte_ring/rte_ring.h')
| -rw-r--r-- | lib/librte_ring/rte_ring.h | 809 |
1 files changed, 324 insertions, 485 deletions
diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h index 32b8c8d2..97f025a1 100644 --- a/lib/librte_ring/rte_ring.h +++ b/lib/librte_ring/rte_ring.h @@ -1,7 +1,7 @@ /*- * 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 @@ -106,38 +106,30 @@ extern "C" { 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; -#endif - #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) -#ifndef RTE_RING_PAUSE_REP_COUNT -#define RTE_RING_PAUSE_REP_COUNT 0 /**< Yield after pause num of times, no yield - * if RTE_RING_PAUSE_REP not defined. */ +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 -struct rte_memzone; /* forward declaration, so as not to require memzone.h */ +/* 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. @@ -155,68 +147,29 @@ struct rte_ring { * compatibility requirements, it could be changed to RTE_RING_NAMESIZE * next time the ABI changes */ - char name[RTE_MEMZONE_NAMESIZE]; /**< Name of the ring. */ - int flags; /**< Flags supplied at creation. */ + 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. */ /** 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[] __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 */ -/** - * @internal When debug is enabled, store ring statistics. - * @param r - * A pointer to the ring. - * @param name - * The name of the statistics field to increment in the ring. - * @param n - * The number to add to the object-oriented statistics. - */ -#ifdef RTE_LIBRTE_RING_DEBUG -#define __RING_STAT_ADD(r, name, n) do { \ - unsigned __lcore_id = rte_lcore_id(); \ - if (__lcore_id < RTE_MAX_LCORE) { \ - 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 +/* @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 /** * Calculate the memory size needed for a ring @@ -321,26 +274,6 @@ struct rte_ring *rte_ring_create(const char *name, unsigned count, void rte_ring_free(struct rte_ring *r); /** - * 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). - * - * @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. - */ -int rte_ring_set_water_mark(struct rte_ring *r, unsigned count); - -/** * Dump the status of the ring to a file. * * @param f @@ -353,171 +286,147 @@ void rte_ring_dump(FILE *f, const struct rte_ring *r); /* 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. * 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 inline __attribute__((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 inline __attribute__((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 mask = r->mask; + unsigned int max = n; int success; - unsigned i, rep = 0; - uint32_t mask = r->prod.mask; - int ret; - - /* Avoid the unnecessary cmpset operation below, which is also - * potentially harmful when n equals 0. */ - if (n == 0) - return 0; - /* move prod.head atomically */ do { /* Reset n to the initial burst count */ n = max; - prod_head = r->prod.head; - cons_tail = r->cons.tail; + *old_head = r->prod.head; + 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 + * *old_head > cons_tail). So 'free_entries' is always between 0 * and size(ring)-1. */ - free_entries = (mask + cons_tail - prod_head); + *free_entries = (mask + 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_smp_wmb(); - - /* 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 preceded us, - * we need to wait for them to complete - */ - while (unlikely(r->prod.tail != prod_head)) { - rte_pause(); - - /* Set RTE_RING_PAUSE_REP_COUNT to avoid spin too long waiting - * for other thread finish. It gives pre-empted thread a chance - * to proceed and finish with ring dequeue operation. */ - if (RTE_RING_PAUSE_REP_COUNT && - ++rep == RTE_RING_PAUSE_REP_COUNT) { - rep = 0; - sched_yield(); - } - } - 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). @@ -525,242 +434,142 @@ __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 inline __attribute__((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(); + 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(); - /* 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; + 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 inline __attribute__((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, rep = 0; - uint32_t mask = r->prod.mask; - - /* Avoid the unnecessary cmpset operation below, which is also - * potentially harmful when n equals 0. */ - if (n == 0) - return 0; /* 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; + 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_smp_rmb(); - - /* - * 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(); - - /* Set RTE_RING_PAUSE_REP_COUNT to avoid spin too long waiting - * for other thread finish. It gives pre-empted thread a chance - * to proceed and finish with ring dequeue operation. */ - if (RTE_RING_PAUSE_REP_COUNT && - ++rep == RTE_RING_PAUSE_REP_COUNT) { - rep = 0; - sched_yield(); - } - } - __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 inline __attribute__((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(); + 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(); - __RING_STAT_ADD(r, deq_success, n); - r->cons.tail = cons_next; - return behavior == RTE_RING_QUEUE_FIXED ? 0 : n; + update_tail(&r->cons, cons_head, cons_next, is_sc); + +end: + if (available != NULL) + *available = entries - n; + return n; } /** @@ -775,17 +584,18 @@ __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 inline unsigned int __attribute__((always_inline)) 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); } /** @@ -797,17 +607,18 @@ 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 inline unsigned int __attribute__((always_inline)) 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); } /** @@ -823,20 +634,18 @@ 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 inline unsigned int __attribute__((always_inline)) 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); } /** @@ -851,14 +660,12 @@ 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)) 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; } /** @@ -870,14 +677,12 @@ 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)) 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; } /** @@ -893,17 +698,12 @@ 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)) 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; } /** @@ -918,15 +718,18 @@ 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 inline unsigned int __attribute__((always_inline)) +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); } /** @@ -939,15 +742,18 @@ 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 inline unsigned int __attribute__((always_inline)) +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); } /** @@ -963,18 +769,18 @@ 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 inline unsigned int __attribute__((always_inline)) +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); } /** @@ -995,7 +801,7 @@ rte_ring_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n) static inline int __attribute__((always_inline)) 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 : -ENOBUFS; } /** @@ -1013,7 +819,7 @@ rte_ring_mc_dequeue(struct rte_ring *r, void **obj_p) static inline int __attribute__((always_inline)) 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 : -ENOBUFS; } /** @@ -1035,10 +841,7 @@ rte_ring_sc_dequeue(struct rte_ring *r, void **obj_p) static inline int __attribute__((always_inline)) 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; } /** @@ -1055,7 +858,7 @@ 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 ((cons_tail - prod_tail - 1) & r->mask) == 0; } /** @@ -1088,7 +891,7 @@ rte_ring_count(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 (prod_tail - cons_tail) & r->mask; } /** @@ -1104,7 +907,21 @@ rte_ring_free_count(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 (cons_tail - prod_tail - 1) & r->mask; +} + +/** + * Return the size of the ring. + * + * @param r + * A pointer to the ring structure. + * @return + * The number of elements which can be stored in the ring. + */ +static inline unsigned int +rte_ring_get_size(const struct rte_ring *r) +{ + return r->size; } /** @@ -1139,14 +956,18 @@ 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 unsigned __attribute__((always_inline)) 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); } /** @@ -1158,14 +979,18 @@ 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 unsigned __attribute__((always_inline)) 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); } /** @@ -1181,17 +1006,18 @@ 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 unsigned __attribute__((always_inline)) 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); } /** @@ -1208,13 +1034,18 @@ 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 unsigned __attribute__((always_inline)) -rte_ring_mc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) +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); } /** @@ -1228,13 +1059,18 @@ 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 unsigned __attribute__((always_inline)) -rte_ring_sc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) +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); } /** @@ -1250,16 +1086,19 @@ 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 */ static inline unsigned __attribute__((always_inline)) -rte_ring_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n) +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 |