#include <rte_atomic.h>
#include <rte_branch_prediction.h>
+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 */
+};
#ifdef RTE_LIBRTE_RING_DEBUG
/**
/** Ring producer status. */
struct prod {
- volatile uint32_t bulk_default; /**< Default bulk count. */
uint32_t watermark; /**< Maximum items before EDQUOT. */
uint32_t sp_enqueue; /**< True, if single producer. */
uint32_t size; /**< Size of ring. */
/** Ring consumer status. */
struct cons {
- volatile uint32_t bulk_default; /**< Default bulk count. */
uint32_t sc_dequeue; /**< True, if single consumer. */
uint32_t size; /**< Size of the ring. */
uint32_t mask; /**< Mask (size-1) of ring. */
#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 */
/**
- * When debug is enabled, store ring statistics.
+ * @internal When debug is enabled, store ring statistics.
* @param r
* A pointer to the ring.
* @param name
*
* 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. The default bulk count is initialized to 1.
+ * disabled by default.
* Note that the real usable ring size is *count-1* instead of
* *count*.
*
struct rte_ring *rte_ring_create(const char *name, unsigned count,
int socket_id, unsigned flags);
-/**
- * Set the default bulk count for enqueue/dequeue.
- *
- * The parameter *count* is the default number of bulk elements to
- * get/put when using ``rte_ring_*_{en,de}queue_bulk()``. It must be
- * greater than 0 and less than half of the ring size.
- *
- * @param r
- * A pointer to the ring structure.
- * @param count
- * A new water mark value.
- * @return
- * - 0: Success; default_bulk_count changed.
- * - -EINVAL: Invalid count value.
- */
-static inline int
-rte_ring_set_bulk_count(struct rte_ring *r, unsigned count)
-{
- if (unlikely(count == 0 || count >= r->prod.size))
- return -EINVAL;
-
- r->prod.bulk_default = r->cons.bulk_default = count;
- return 0;
-}
-
-/**
- * Get the default bulk count for enqueue/dequeue.
- *
- * @param r
- * A pointer to the ring structure.
- * @return
- * The default bulk count for enqueue/dequeue.
- */
-static inline unsigned
-rte_ring_get_bulk_count(struct rte_ring *r)
-{
- return r->prod.bulk_default;
-}
-
/**
* Change the high water mark.
*
* *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 necessarilly at
+ * This function can be called at any time (not necessarily at
* initialization).
*
* @param r
void rte_ring_dump(const struct rte_ring *r);
/**
- * Enqueue several objects on the ring (multi-producers safe).
+ * @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 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. The
- * value must be strictly positive.
+ * 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
+ * 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.
*/
static inline int
-rte_ring_mp_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
- unsigned n)
+__rte_ring_mp_do_enqueue(struct rte_ring *r, void * const *obj_table,
+ unsigned n, enum rte_ring_queue_behavior behavior)
{
uint32_t prod_head, prod_next;
uint32_t cons_tail, free_entries;
+ const unsigned max = n;
int success;
unsigned i;
uint32_t mask = r->prod.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
/* check that we have enough room in ring */
if (unlikely(n > free_entries)) {
- __RING_STAT_ADD(r, enq_fail, n);
- return -ENOBUFS;
+ 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->ring[(prod_head + i) & mask] = obj_table[i];
rte_wmb();
- /* return -EDQUOT if we exceed the watermark */
+ /* if we exceed the watermark */
if (unlikely(((mask + 1) - free_entries + n) > r->prod.watermark)) {
- ret = -EDQUOT;
+ ret = (behavior == RTE_RING_QUEUE_FIXED) ? -EDQUOT :
+ (int)(n | RTE_RING_QUOT_EXCEED);
__RING_STAT_ADD(r, enq_quota, n);
}
else {
- ret = 0;
+ ret = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : n;
__RING_STAT_ADD(r, enq_success, n);
}
}
/**
- * Enqueue several objects on a ring (NOT multi-producers safe).
+ * @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. The
- * value must be strictly positive.
+ * 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
- * - 0: Success; objects enqueued.
+ * 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.
+ * - -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.
*/
static inline int
-rte_ring_sp_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
- unsigned n)
+__rte_ring_sp_do_enqueue(struct rte_ring *r, void * const *obj_table,
+ unsigned n, enum rte_ring_queue_behavior behavior)
{
uint32_t prod_head, cons_tail;
uint32_t prod_next, free_entries;
/* check that we have enough room in ring */
if (unlikely(n > free_entries)) {
- __RING_STAT_ADD(r, enq_fail, n);
- return -ENOBUFS;
+ 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->ring[(prod_head + i) & mask] = obj_table[i];
rte_wmb();
- /* return -EDQUOT if we exceed the watermark */
+ /* if we exceed the watermark */
if (unlikely(((mask + 1) - free_entries + n) > r->prod.watermark)) {
- ret = -EDQUOT;
+ ret = (behavior == RTE_RING_QUEUE_FIXED) ? -EDQUOT :
+ (int)(n | RTE_RING_QUOT_EXCEED);
__RING_STAT_ADD(r, enq_quota, n);
}
else {
- ret = 0;
+ ret = (behavior == RTE_RING_QUEUE_FIXED) ? 0 : n;
__RING_STAT_ADD(r, enq_success, n);
}
return ret;
}
+/**
+ * @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
+ * 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.
+ */
+
+static inline int
+__rte_ring_mc_do_dequeue(struct rte_ring *r, void **obj_table,
+ unsigned n, enum rte_ring_queue_behavior behavior)
+{
+ uint32_t cons_head, prod_tail;
+ uint32_t cons_next, entries;
+ const unsigned 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;
+ /* 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 (unlikely(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);
+ } while (unlikely(success == 0));
+
+ /* copy in table */
+ rte_rmb();
+ for (i = 0; likely(i < n); i++) {
+ obj_table[i] = r->ring[(cons_head + i) & mask];
+ }
+
+ /*
+ * 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;
+}
+
+/**
+ * @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
+ * 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.
+ */
+static inline int
+__rte_ring_sc_do_dequeue(struct rte_ring *r, void **obj_table,
+ unsigned n, enum rte_ring_queue_behavior behavior)
+{
+ 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 (unlikely(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 */
+ rte_rmb();
+ for (i = 0; likely(i < n); i++) {
+ obj_table[i] = r->ring[(cons_head + i) & mask];
+ }
+
+ __RING_STAT_ADD(r, deq_success, n);
+ r->cons.tail = cons_next;
+ return behavior == RTE_RING_QUEUE_FIXED ? 0 : n;
+}
+
+/**
+ * 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.
+ * @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.
+ */
+static inline int
+rte_ring_mp_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
+ unsigned n)
+{
+ return __rte_ring_mp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_FIXED);
+}
+
+/**
+ * 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.
+ * @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
+rte_ring_sp_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
+ unsigned n)
+{
+ return __rte_ring_sp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_FIXED);
+}
+
/**
* Enqueue several objects on a ring.
*
* @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,
- * must be strictly positive
+ * The number of objects to dequeue from the ring to the obj_table.
* @return
* - 0: Success; objects dequeued.
* - -ENOENT: Not enough entries in the ring to dequeue; no object is
static inline int
rte_ring_mc_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n)
{
- uint32_t cons_head, prod_tail;
- uint32_t cons_next, entries;
- int success;
- unsigned i;
- uint32_t mask = r->prod.mask;
-
- /* move cons.head atomically */
- do {
- 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);
-
- /* check that we have enough entries in ring */
- if (unlikely(n > entries)) {
- __RING_STAT_ADD(r, deq_fail, n);
- return -ENOENT;
- }
-
- cons_next = cons_head + n;
- success = rte_atomic32_cmpset(&r->cons.head, cons_head,
- cons_next);
- } while (unlikely(success == 0));
-
- /* copy in table */
- rte_rmb();
- for (i = 0; likely(i < n); i++) {
- obj_table[i] = r->ring[(cons_head + i) & mask];
- }
-
- /*
- * If there are other dequeues in progress that preceeded 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 0;
+ return __rte_ring_mc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED);
}
/**
static inline int
rte_ring_sc_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n)
{
- 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;
-
- /* check that we have enough entries in ring */
- if (unlikely(n > entries)) {
- __RING_STAT_ADD(r, deq_fail, n);
- return -ENOENT;
- }
-
- cons_next = cons_head + n;
- r->cons.head = cons_next;
-
- /* copy in table */
- rte_rmb();
- for (i = 0; likely(i < n); i++) {
- obj_table[i] = r->ring[(cons_head + i) & mask];
- }
-
- __RING_STAT_ADD(r, deq_success, n);
- r->cons.tail = cons_next;
- return 0;
+ return __rte_ring_sc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED);
}
/**
*/
struct rte_ring *rte_ring_lookup(const char *name);
+/**
+ * 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.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static inline int
+rte_ring_mp_enqueue_burst(struct rte_ring *r, void * const *obj_table,
+ unsigned n)
+{
+ return __rte_ring_mp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE);
+}
+
+/**
+ * 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.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static inline int
+rte_ring_sp_enqueue_burst(struct rte_ring *r, void * const *obj_table,
+ unsigned n)
+{
+ return __rte_ring_sp_do_enqueue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE);
+}
+
+/**
+ * Enqueue several objects on a ring.
+ *
+ * This function calls the multi-producer or the single-producer
+ * version depending on the default behavior that was specified at
+ * ring creation time (see flags).
+ *
+ * @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.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static inline int
+rte_ring_enqueue_burst(struct rte_ring *r, void * const *obj_table,
+ unsigned n)
+{
+ 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);
+}
+
+/**
+ * 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.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static inline int
+rte_ring_mc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n)
+{
+ return __rte_ring_mc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE);
+}
+
+/**
+ * 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.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static inline int
+rte_ring_sc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n)
+{
+ return __rte_ring_sc_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_VARIABLE);
+}
+
+/**
+ * Dequeue multiple objects from a ring up to a maximum number.
+ *
+ * This function calls the multi-consumers or the single-consumer
+ * version, depending on the default behaviour that was specified at
+ * ring creation time (see flags).
+ *
+ * @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.
+ * @return
+ * - Number of objects dequeued, or a negative error code on error
+ */
+static inline int
+rte_ring_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n)
+{
+ 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);
+}
+
#ifdef __cplusplus
}
#endif
git.droids-corp.org / dpdk.git / blobdiff