-/* 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 { \
- unsigned int i; \
- const uint32_t size = r->size; \
- uint32_t idx = prod_head & mask; \
- 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]; \
- } \
- 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++]; \
- } \
- } else { \
- for (i = 0; idx < size; i++, idx++)\
- r->ring[idx] = obj_table[i]; \
- for (idx = 0; i < n; i++, idx++) \
- r->ring[idx] = obj_table[i]; \
- } \
-} 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 { \
- unsigned int i; \
- uint32_t idx = cons_head & mask; \
- const uint32_t size = r->size; \
- 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]; \
- } \
- 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++]; \
- } \
- } else { \
- for (i = 0; idx < size; i++, idx++) \
- obj_table[i] = r->ring[idx]; \
- for (idx = 0; i < n; i++, idx++) \
- obj_table[i] = r->ring[idx]; \
- } \
-} while (0)
-
-/**
- * @internal Enqueue several objects on the ring (multi-producers safe).
- *
- * This function uses a "compare and set" instruction to move the
- * producer index atomically.
- *
- * @param r
- * A pointer to the ring structure.
- * @param 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 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
- * @return
- * Actual number of objects enqueued.
- * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
- */
-static inline unsigned int __attribute__((always_inline))
-__rte_ring_mp_do_enqueue(struct rte_ring *r, void * const *obj_table,
- unsigned int n, enum rte_ring_queue_behavior behavior,
- unsigned int *free_space)
-{
- uint32_t prod_head, prod_next;
- uint32_t cons_tail, free_entries;
- const unsigned int max = n;
- int success;
- uint32_t mask = r->mask;
-
- /* 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
- * (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))
- n = (behavior == RTE_RING_QUEUE_FIXED) ?
- 0 : free_entries;
-
- if (n == 0)
- goto end;
-
- prod_next = prod_head + n;
- success = rte_atomic32_cmpset(&r->prod.head, prod_head,
- prod_next);
- } while (unlikely(success == 0));
-
- /* write entries in ring */
- ENQUEUE_PTRS();
- rte_smp_wmb();
-
- /*
- * 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();
-
- r->prod.tail = prod_next;
-end:
- if (free_space != NULL)
- *free_space = free_entries - n;
- return n;
-}
-
-/**
- * @internal Enqueue several objects on a ring (NOT multi-producers safe).
- *
- * @param r
- * A pointer to the ring structure.
- * @param 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 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
- * @return
- * Actual number of objects enqueued.
- * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
- */
-static inline unsigned int __attribute__((always_inline))
-__rte_ring_sp_do_enqueue(struct rte_ring *r, void * const *obj_table,
- unsigned int n, enum rte_ring_queue_behavior behavior,
- unsigned int *free_space)
-{
- uint32_t prod_head, cons_tail;
- uint32_t prod_next, free_entries;
- uint32_t mask = r->mask;
-
- 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))
- n = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : free_entries;
-
- if (n == 0)
- goto end;
-
-
- prod_next = prod_head + n;
- r->prod.head = prod_next;
-
- /* write entries in ring */
- ENQUEUE_PTRS();
- rte_smp_wmb();
-
- r->prod.tail = prod_next;
-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.
- *
- * @param r
- * A pointer to the ring structure.
- * @param 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 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
- * @return
- * - Actual number of objects dequeued.
- * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
- */
-
-static inline unsigned int __attribute__((always_inline))
-__rte_ring_mc_do_dequeue(struct rte_ring *r, void **obj_table,
- unsigned int n, enum rte_ring_queue_behavior behavior,
- unsigned int *available)
-{
- uint32_t cons_head, prod_tail;
- uint32_t cons_next, entries;
- const unsigned max = n;
- int success;
- uint32_t mask = r->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;
- /* 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);
-
- /* Set the actual entries for dequeue */
- if (n > entries)
- n = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : entries;
-
- if (unlikely(n == 0))
- goto end;
-
- cons_next = cons_head + n;
- success = rte_atomic32_cmpset(&r->cons.head, cons_head,
- cons_next);
- } 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();
-
- r->cons.tail = cons_next;
-end:
- if (available != NULL)
- *available = entries - 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
- *
- * @param r
- * A pointer to the ring structure.
- * @param 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 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
- * @return
- * - Actual number of objects dequeued.
- * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
- */
-static inline unsigned int __attribute__((always_inline))
-__rte_ring_sc_do_dequeue(struct rte_ring *r, void **obj_table,
- unsigned int n, enum rte_ring_queue_behavior behavior,
- unsigned int *available)
-{
- uint32_t cons_head, prod_tail;
- uint32_t cons_next, entries;
- uint32_t mask = r->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)
- n = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : entries;
-
- if (unlikely(entries == 0))
- goto end;
-
- cons_next = cons_head + n;
- r->cons.head = cons_next;
-
- /* copy in table */
- DEQUEUE_PTRS();
- rte_smp_rmb();
-
- r->cons.tail = cons_next;
-end:
- if (available != NULL)
- *available = entries - n;
- return n;
-}
-