#define SVM_FIFO_INVALID_INDEX ((u32)~0)
#define SVM_FIFO_MAX_EVT_SUBSCRIBERS 7
-typedef enum svm_fifo_tx_ntf_
+typedef enum svm_fifo_deq_ntf_
{
- SVM_FIFO_NO_TX_NOTIF = 0,
- SVM_FIFO_WANT_TX_NOTIF = 1,
- SVM_FIFO_WANT_TX_NOTIF_IF_FULL = 2,
-} svm_fifo_tx_ntf_t;
+ SVM_FIFO_NO_DEQ_NOTIF = 0, /**< No notification requested */
+ SVM_FIFO_WANT_DEQ_NOTIF = 1, /**< Notify on dequeue */
+ SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL = 2, /**< Notify on transition from full */
+ SVM_FIFO_WANT_DEQ_NOTIF_IF_EMPTY = 4, /**< Notify on transition to empty */
+} svm_fifo_deq_ntf_t;
typedef struct
{
u32 start_byte; /**< chunk start byte */
u32 length; /**< length of chunk in bytes */
struct svm_fifo_chunk_ *next; /**< pointer to next chunk in linked-lists */
+ rb_node_index_t rb_index; /**< node index if chunk in rbtree */
u8 data[0]; /**< start of chunk data */
} svm_fifo_chunk_t;
typedef enum svm_fifo_flag_
{
- SVM_FIFO_F_SIZE_UPDATE = 1 << 0,
- SVM_FIFO_F_MULTI_CHUNK = 1 << 1,
- SVM_FIFO_F_LL_TRACKED = 1 << 2,
+ SVM_FIFO_F_MULTI_CHUNK = 1 << 0,
+ SVM_FIFO_F_GROW = 1 << 1,
+ SVM_FIFO_F_SHRINK = 1 << 2,
+ SVM_FIFO_F_COLLECT_CHUNKS = 1 << 3,
+ SVM_FIFO_F_LL_TRACKED = 1 << 4,
+ SVM_FIFO_F_SINGLE_THREAD_OWNED = 1 << 5,
} svm_fifo_flag_t;
typedef struct _svm_fifo
CLIB_CACHE_LINE_ALIGN_MARK (shared_first);
u32 size; /**< size of the fifo in bytes */
u32 nitems; /**< usable size (size-1) */
- u8 flags; /**< fifo flags */
svm_fifo_chunk_t *start_chunk;/**< first chunk in fifo chunk list */
svm_fifo_chunk_t *end_chunk; /**< end chunk in fifo chunk list */
- svm_fifo_chunk_t *new_chunks; /**< chunks yet to be added to list */
- rb_tree_t chunk_lookup;
+ rb_tree_t ooo_enq_lookup; /**< rbtree for ooo enq chunk lookup */
+ rb_tree_t ooo_deq_lookup; /**< rbtree for ooo deq chunk lookup */
+ u8 flags; /**< fifo flags */
+ u8 slice_index; /**< segment slice for fifo */
CLIB_CACHE_LINE_ALIGN_MARK (shared_second);
volatile u32 has_event; /**< non-zero if deq event exists */
u32 client_session_index; /**< app session index */
u8 master_thread_index; /**< session layer thread index */
u8 client_thread_index; /**< app worker index */
+ i8 refcnt; /**< reference count */
u32 segment_manager; /**< session layer segment manager index */
u32 segment_index; /**< segment index in segment manager */
- u32 freelist_index; /**< aka log2(allocated_size) - const. */
- i8 refcnt; /**< reference count */
struct _svm_fifo *next; /**< next in freelist/active chain */
struct _svm_fifo *prev; /**< prev in active chain */
+ svm_fifo_chunk_t *new_chunks; /**< chunks yet to be added to list */
+ u32 size_decrement; /**< bytes to remove from fifo */
CLIB_CACHE_LINE_ALIGN_MARK (consumer);
u32 head; /**< fifo head position/byte */
svm_fifo_chunk_t *head_chunk; /**< tracks chunk where head lands */
svm_fifo_chunk_t *ooo_deq; /**< last chunk used for ooo dequeue */
- volatile u32 want_tx_ntf; /**< producer wants nudge */
- volatile u32 has_tx_ntf;
+ volatile u32 want_deq_ntf; /**< producer wants nudge */
+ volatile u32 has_deq_ntf;
CLIB_CACHE_LINE_ALIGN_MARK (producer);
u32 tail; /**< fifo tail position/byte */
svm_fifo_trace_elem_t *trace;
#endif
- svm_fifo_chunk_t default_chunk;
} svm_fifo_t;
typedef enum
*head = clib_atomic_load_acq_n (&f->head);
}
-/* Load head and tail independent of producer/consumer role
+/**
+ * Load head and tail independent of producer/consumer role
*
* Internal function.
*/
}
/**
- * Fifo free bytes, i.e., number of free bytes
+ * Distance to a from b, i.e., a - b in the fifo
*
- * Internal function
+ * Internal function.
*/
static inline u32
-f_free_count (svm_fifo_t * f, u32 head, u32 tail)
+f_distance_to (svm_fifo_t * f, u32 a, u32 b)
{
- return (f->nitems + head - tail);
+ return ((f->size + a - b) % f->size);
}
/**
- * Fifo current size, i.e., number of bytes enqueued
+ * Distance from a to b, i.e., b - a in the fifo
*
* Internal function.
*/
static inline u32
-f_cursize (svm_fifo_t * f, u32 head, u32 tail)
+f_distance_from (svm_fifo_t * f, u32 a, u32 b)
{
- return (f->nitems - f_free_count (f, head, tail));
+ return ((f->size + b - a) % f->size);
}
/**
- * Distance to a from b, i.e., a - b in the fifo
+ * Fifo current size, i.e., number of bytes enqueued
*
* Internal function.
*/
static inline u32
-f_distance_to (svm_fifo_t * f, u32 a, u32 b)
+f_cursize (svm_fifo_t * f, u32 head, u32 tail)
{
- return ((f->size + a - b) % f->size);
+ return (head <= tail ? tail - head : f->size + tail - head);
}
/**
- * Distance from a to b, i.e., b - a in the fifo
+ * Fifo free bytes, i.e., number of free bytes
*
- * Internal function.
+ * Internal function
*/
static inline u32
-f_distance_from (svm_fifo_t * f, u32 a, u32 b)
+f_free_count (svm_fifo_t * f, u32 head, u32 tail)
{
- return ((f->size + b - a) % f->size);
+ return (f->nitems - f_cursize (f, head, tail));
}
+/**
+ * Try to shrink fifo size.
+ *
+ * Internal function.
+ */
+void svm_fifo_try_shrink (svm_fifo_t * f, u32 head, u32 tail);
+
/**
* Create fifo of requested size
*
/**
* Initialize fifo
*
+ * @param f fifo
* @param size size for fifo
*/
void svm_fifo_init (svm_fifo_t * f, u32 size);
+/**
+ * Initialize fifo chunks and rbtree
+ *
+ * @param f fifo
+ */
+void svm_fifo_init_chunks (svm_fifo_t * f);
/**
* Allocate a fifo chunk on heap
*
* @param c chunk or linked list of chunks to be added
*/
void svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c);
+/**
+ * Request to reduce fifo size by amount of bytes
+ *
+ * Because the producer might be enqueuing data when this is called, the
+ * actual size update is only applied when producer tries to enqueue new
+ * data, unless @param try_shrink is set.
+ *
+ * @param f fifo
+ * @param len number of bytes to remove from fifo. The actual number
+ * of bytes to be removed will be less or equal to this
+ * value.
+ * @param try_shrink flg to indicate if it's safe to try to shrink fifo
+ * size. It should be set only if this is called by the
+ * producer of if the producer is not using the fifo
+ * @return actual length fifo size will be reduced by
+ */
+int svm_fifo_reduce_size (svm_fifo_t * f, u32 len, u8 try_shrink);
+/**
+ * Removes chunks that are after fifo end byte
+ *
+ * Needs to be called with segment heap pushed.
+ *
+ * @param f fifo
+ */
+svm_fifo_chunk_t *svm_fifo_collect_chunks (svm_fifo_t * f);
/**
* Free fifo and associated state
*
*/
int svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len,
u8 * src);
+
+/**
+ * Advance tail pointer
+ *
+ * Useful for moving tail pointer after external enqueue.
+ *
+ * @param f fifo
+ * @param len number of bytes to add to tail
+ */
+void svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len);
/**
* Overwrite fifo head with new data
*
* @return number of out of order segments
*/
u32 svm_fifo_n_ooo_segments (svm_fifo_t * f);
-/*
+/**
* First out-of-order segment for fifo
*
* @param f fifo
* @return first out-of-order segment for fifo
*/
ooo_segment_t *svm_fifo_first_ooo_segment (svm_fifo_t * f);
+/**
+ * Check if fifo is sane. Debug only.
+ *
+ * @param f fifo
+ * @return 1 if sane, 0 otherwise
+ */
+u8 svm_fifo_is_sane (svm_fifo_t * f);
+/**
+ * Declare this fifo is used by only a single thread.
+ * In this special case, fifo-growth can be done in an efficient way without delay.
+ *
+ * @param f fifo
+ * @return 1 if the fifo is already owned by another thread, 0 otherwise
+ */
+u8 svm_fifo_set_single_thread_owned (svm_fifo_t * f);
format_function_t format_svm_fifo;
/**
{
u32 head, tail;
f_load_head_tail_all_acq (f, &head, &tail);
- return head % f->size > tail % f->size;
+ return head > tail;
}
/**
{
u32 head, tail;
f_load_head_tail_prod (f, &head, &tail);
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SHRINK))
+ svm_fifo_try_shrink (f, head, tail);
return f_free_count (f, head, tail);
}
{
u32 head, tail;
f_load_head_tail_all_acq (f, &head, &tail);
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SHRINK))
+ svm_fifo_try_shrink (f, head, tail);
return f_free_count (f, head, tail);
}
svm_fifo_max_read_chunk (svm_fifo_t * f)
{
u32 head, tail;
- u32 head_idx, tail_idx;
f_load_head_tail_cons (f, &head, &tail);
- head_idx = head % f->size;
- tail_idx = tail % f->size;
- return tail_idx > head_idx ? (tail_idx - head_idx) : (f->size - head_idx);
+ return tail >= head ? (tail - head) : (f->size - head);
}
/**
svm_fifo_max_write_chunk (svm_fifo_t * f)
{
u32 head, tail;
- u32 head_idx, tail_idx;
f_load_head_tail_prod (f, &head, &tail);
- head_idx = head % f->size;
- tail_idx = tail % f->size;
- return tail_idx >= head_idx ? (f->size - tail_idx) : (head_idx - tail_idx);
-}
-
-/**
- * Advance tail pointer
- *
- * Useful for moving tail pointer after external enqueue.
- *
- * @param f fifo
- * @param len number of bytes to add to tail
- */
-static inline void
-svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len)
-{
- ASSERT (len <= svm_fifo_max_enqueue_prod (f));
- /* load-relaxed: producer owned index */
- u32 tail = f->tail;
- tail += len;
- /* store-rel: producer owned index (paired with load-acq in consumer) */
- clib_atomic_store_rel_n (&f->tail, tail);
+ return tail >= head ? f->size - tail : f_free_count (f, head, tail);
}
static inline u8 *
svm_fifo_head (svm_fifo_t * f)
{
/* load-relaxed: consumer owned index */
- return (f->head_chunk->data
- + ((f->head % f->size) - f->head_chunk->start_byte));
+ return (f->head_chunk->data + (f->head - f->head_chunk->start_byte));
}
static inline u8 *
svm_fifo_tail (svm_fifo_t * f)
{
/* load-relaxed: producer owned index */
- return (f->tail_chunk->data
- + ((f->tail % f->size) - f->tail_chunk->start_byte));
+ return (f->tail_chunk->data + (f->tail - f->tail_chunk->start_byte));
}
static inline u8
}
/**
- * Set specific want tx notification flag
+ * Set specific want notification flag
*
- * For list of flags see @ref svm_fifo_tx_ntf_t
+ * For list of flags see @ref svm_fifo_deq_ntf_t
*
* @param f fifo
* @param ntf_type type of notification requested
*/
static inline void
-svm_fifo_add_want_tx_ntf (svm_fifo_t * f, u8 ntf_type)
+svm_fifo_add_want_deq_ntf (svm_fifo_t * f, u8 ntf_type)
{
- f->want_tx_ntf |= ntf_type;
+ f->want_deq_ntf |= ntf_type;
}
/**
- * Clear specific want tx notification flag
+ * Clear specific want notification flag
*
- * For list of flags see @ref svm_fifo_tx_ntf_t
+ * For list of flags see @ref svm_fifo_ntf_t
*
* @param f fifo
* @param ntf_type type of notification to be cleared
*/
static inline void
-svm_fifo_del_want_tx_ntf (svm_fifo_t * f, u8 ntf_type)
+svm_fifo_del_want_deq_ntf (svm_fifo_t * f, u8 ntf_type)
{
- f->want_tx_ntf &= ~ntf_type;
+ f->want_deq_ntf &= ~ntf_type;
}
/**
- * Clear the want tx notification flag and set has tx notification
+ * Clear the want notification flag and set has notification
*
- * Should be used after enqueuing a tx event. This clears the
- * SVM_FIFO_WANT_TX_NOTIF flag but it does not clear
- * SVM_FIFO_WANT_TX_NOTIF_IF_FULL. If the latter was set, has_tx_ntf is
- * set to avoid enqueueing tx events for for all dequeue operations until
+ * Should be used after enqueuing an event. This clears the
+ * SVM_FIFO_WANT_NOTIF flag but it does not clear
+ * SVM_FIFO_WANT_NOTIF_IF_FULL. If the latter was set, has_ntf is
+ * set to avoid enqueueing events for for all dequeue operations until
* it is manually cleared.
*
* @param f fifo
*/
static inline void
-svm_fifo_clear_tx_ntf (svm_fifo_t * f)
+svm_fifo_clear_deq_ntf (svm_fifo_t * f)
{
- /* Set the flag if want_tx_notif_if_full was the only ntf requested */
- f->has_tx_ntf = f->want_tx_ntf == SVM_FIFO_WANT_TX_NOTIF_IF_FULL;
- svm_fifo_del_want_tx_ntf (f, SVM_FIFO_WANT_TX_NOTIF);
+ /* Set the flag if want_notif_if_full was the only ntf requested */
+ f->has_deq_ntf = f->want_deq_ntf == SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL;
+ svm_fifo_del_want_deq_ntf (f, SVM_FIFO_WANT_DEQ_NOTIF);
}
/**
- * Clear has tx notification flag
+ * Clear has notification flag
*
- * The fifo generates only one event per SVM_FIFO_WANT_TX_NOTIF_IF_FULL
- * request and sets has_tx_ntf. To received new events the flag must be
+ * The fifo generates only one event per SVM_FIFO_WANT_NOTIF_IF_FULL
+ * request and sets has_ntf. To received new events the flag must be
* cleared using this function.
*
* @param f fifo
*/
static inline void
-svm_fifo_reset_tx_ntf (svm_fifo_t * f)
+svm_fifo_reset_has_deq_ntf (svm_fifo_t * f)
{
- f->has_tx_ntf = 0;
+ f->has_deq_ntf = 0;
}
/**
- * Check if fifo needs tx notification
+ * Check if fifo needs dequeue notification
*
- * Determines based on tx notification request flags and state of the fifo if
- * a tx io event should be generated.
+ * Determines based on notification request flags and state of the fifo if
+ * an event should be generated.
*
* @param f fifo
* @param n_last_deq number of bytes last dequeued
- * @return 1 if tx io event should be generated, 0 otherwise
+ * @return 1 if event should be generated, 0 otherwise
*/
static inline u8
-svm_fifo_needs_tx_ntf (svm_fifo_t * f, u32 n_last_deq)
+svm_fifo_needs_deq_ntf (svm_fifo_t * f, u32 n_last_deq)
{
- u8 want_ntf = f->want_tx_ntf;
+ u8 want_ntf = f->want_deq_ntf;
- if (PREDICT_TRUE (want_ntf == SVM_FIFO_NO_TX_NOTIF))
+ if (PREDICT_TRUE (want_ntf == SVM_FIFO_NO_DEQ_NOTIF))
return 0;
- else if (want_ntf & SVM_FIFO_WANT_TX_NOTIF)
+ else if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF)
return 1;
- else if (want_ntf & SVM_FIFO_WANT_TX_NOTIF_IF_FULL)
+ if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL)
{
u32 max_deq = svm_fifo_max_dequeue_cons (f);
u32 nitems = f->nitems;
- if (!f->has_tx_ntf && max_deq < nitems
+ if (!f->has_deq_ntf && max_deq < nitems
&& max_deq + n_last_deq >= nitems)
return 1;
-
- return 0;
+ }
+ if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF_IF_EMPTY)
+ {
+ if (!f->has_deq_ntf && svm_fifo_is_empty (f))
+ return 1;
}
return 0;
}
Code Review / vpp.git / blobdiff