#include <vppinfra/vec.h>
#include <vppinfra/pool.h>
#include <vppinfra/format.h>
-#include <vppinfra/rbtree.h>
+#include <svm/fifo_types.h>
-/** Out-of-order segment */
-typedef struct
-{
- u32 next; /**< Next linked-list element pool index */
- u32 prev; /**< Previous linked-list element pool index */
- u32 start; /**< Start of segment, normalized*/
- u32 length; /**< Length of segment */
-} ooo_segment_t;
-
-#define SVM_FIFO_TRACE (0)
#define OOO_SEGMENT_INVALID_INDEX ((u32)~0)
#define SVM_FIFO_INVALID_SESSION_INDEX ((u32)~0)
#define SVM_FIFO_INVALID_INDEX ((u32)~0)
-#define SVM_FIFO_MAX_EVT_SUBSCRIBERS 7
typedef enum svm_fifo_deq_ntf_
{
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_WANT_DEQ_NOTIF_IF_EMPTY = 4, /**< Notify on transition to empty */
} svm_fifo_deq_ntf_t;
-typedef struct
-{
- u32 offset;
- u32 len;
- u32 action;
-} svm_fifo_trace_elem_t;
-
-typedef struct svm_fifo_chunk_
-{
- 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 */
- u8 data[0]; /**< start of chunk data */
-} svm_fifo_chunk_t;
-
typedef enum svm_fifo_flag_
{
- 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_F_LL_TRACKED = 1 << 0,
} 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) */
- 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; /**< rbtree for 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 master_session_index; /**< session layer session index */
- 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 */
- struct _svm_fifo *next; /**< next in freelist/active chain */
- struct _svm_fifo *prev; /**< prev in active chain */
- 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_deq_ntf; /**< producer wants nudge */
- volatile u32 has_deq_ntf;
-
- CLIB_CACHE_LINE_ALIGN_MARK (producer);
- u32 tail; /**< fifo tail position/byte */
- u32 ooos_list_head; /**< Head of out-of-order linked-list */
- svm_fifo_chunk_t *tail_chunk; /**< tracks chunk where tail lands */
- svm_fifo_chunk_t *ooo_enq; /**< last chunk used for ooo enqueue */
- ooo_segment_t *ooo_segments; /**< Pool of ooo segments */
- u32 ooos_newest; /**< Last segment to have been updated */
- volatile u8 n_subscribers; /**< Number of subscribers for io events */
- u8 subscribers[SVM_FIFO_MAX_EVT_SUBSCRIBERS];
-
-#if SVM_FIFO_TRACE
- svm_fifo_trace_elem_t *trace;
-#endif
-
-} svm_fifo_t;
-
typedef enum
{
SVM_FIFO_EFULL = -2,
SVM_FIFO_EEMPTY = -3,
+ SVM_FIFO_EGROW = -4,
} svm_fifo_err_t;
typedef struct svm_fifo_seg_
f_load_head_tail_cons (svm_fifo_t * f, u32 * head, u32 * tail)
{
/* load-relaxed: consumer owned index */
- *head = f->head;
+ *head = f->shr->head;
/* load-acq: consumer foreign index (paired with store-rel in producer) */
- *tail = clib_atomic_load_acq_n (&f->tail);
+ *tail = clib_atomic_load_acq_n (&f->shr->tail);
}
/** Load head and tail optimized for producer
f_load_head_tail_prod (svm_fifo_t * f, u32 * head, u32 * tail)
{
/* load relaxed: producer owned index */
- *tail = f->tail;
+ *tail = f->shr->tail;
/* load-acq: producer foreign index (paired with store-rel in consumer) */
- *head = clib_atomic_load_acq_n (&f->head);
+ *head = clib_atomic_load_acq_n (&f->shr->head);
}
/**
f_load_head_tail_all_acq (svm_fifo_t * f, u32 * head, u32 * tail)
{
/* load-acq : consumer foreign index (paired with store-rel) */
- *tail = clib_atomic_load_acq_n (&f->tail);
+ *tail = clib_atomic_load_acq_n (&f->shr->tail);
/* load-acq : producer foriegn index (paired with store-rel) */
- *head = clib_atomic_load_acq_n (&f->head);
+ *head = clib_atomic_load_acq_n (&f->shr->head);
}
/**
- * 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 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->shr->size - f_cursize (f, head, tail));
}
-/**
- * Fifo current size, i.e., number of bytes enqueued
- *
- * Internal function.
- */
-static inline u32
-f_cursize (svm_fifo_t * f, u32 head, u32 tail)
+always_inline u32
+f_chunk_end (svm_fifo_chunk_t * c)
{
- return (head <= tail ? tail - head : f->size + tail - head);
+ return c->start_byte + c->length;
}
-/**
- * Fifo free bytes, i.e., number of free bytes
- *
- * Internal function
- */
-static inline u32
-f_free_count (svm_fifo_t * f, u32 head, u32 tail)
+always_inline int
+f_pos_lt (u32 a, u32 b)
{
- return (f->nitems - f_cursize (f, head, tail));
+ return ((i32) (a - b) < 0);
}
-/**
- * Try to shrink fifo size.
- *
- * Internal function.
- */
-void svm_fifo_try_shrink (svm_fifo_t * f, u32 head, u32 tail);
+always_inline int
+f_pos_leq (u32 a, u32 b)
+{
+ return ((i32) (a - b) <= 0);
+}
+
+always_inline int
+f_pos_gt (u32 a, u32 b)
+{
+ return ((i32) (a - b) > 0);
+}
+
+always_inline int
+f_pos_geq (u32 a, u32 b)
+{
+ return ((i32) (a - b) >= 0);
+}
+
+always_inline u8
+f_chunk_includes_pos (svm_fifo_chunk_t * c, u32 pos)
+{
+ return (f_pos_geq (pos, c->start_byte)
+ && f_pos_lt (pos, c->start_byte + c->length));
+}
+
+always_inline svm_fifo_chunk_t *
+f_start_cptr (svm_fifo_t *f)
+{
+ return fs_chunk_ptr (f->fs_hdr, f->shr->start_chunk);
+}
+
+always_inline svm_fifo_chunk_t *
+f_end_cptr (svm_fifo_t *f)
+{
+ return fs_chunk_ptr (f->fs_hdr, f->shr->end_chunk);
+}
+
+always_inline svm_fifo_chunk_t *
+f_head_cptr (svm_fifo_t *f)
+{
+ return fs_chunk_ptr (f->fs_hdr, f->shr->head_chunk);
+}
+
+always_inline svm_fifo_chunk_t *
+f_tail_cptr (svm_fifo_t *f)
+{
+ return fs_chunk_ptr (f->fs_hdr, f->shr->tail_chunk);
+}
+
+always_inline svm_fifo_chunk_t *
+f_cptr (svm_fifo_t *f, fs_sptr_t cp)
+{
+ return fs_chunk_ptr (f->fs_hdr, cp);
+}
+
+always_inline fs_sptr_t
+f_csptr (svm_fifo_t *f, svm_fifo_chunk_t *c)
+{
+ return fs_chunk_sptr (f->fs_hdr, c);
+}
+
+always_inline void
+f_csptr_link (svm_fifo_t *f, fs_sptr_t cp, svm_fifo_chunk_t *c)
+{
+ fs_chunk_ptr (f->fs_hdr, cp)->next = fs_chunk_sptr (f->fs_hdr, c);
+}
/**
* Create fifo of requested size
* rounded to the next highest power-of-two value.
* @return pointer to new fifo
*/
-svm_fifo_t *svm_fifo_create (u32 size);
+svm_fifo_t *svm_fifo_alloc (u32 size);
/**
* Initialize 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
*
*/
svm_fifo_chunk_t *svm_fifo_chunk_alloc (u32 size);
/**
- * Grow fifo size by adding chunk to chunk list
+ * Ensure the whole fifo size is writeable
*
- * If fifos are allocated on a segment, this should be called with
- * the segment's heap pushed.
+ * Allocates enough chunks to cover the whole fifo size.
*
- * @param f fifo to be extended
- * @param c chunk or linked list of chunks to be added
+ * @param f fifo
*/
-void svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c);
+int svm_fifo_fill_chunk_list (svm_fifo_t * f);
/**
- * Request to reduce fifo size by amount of bytes
+ * Provision and return chunks for number of bytes requested
*
- * 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.
+ * Allocates enough chunks to cover the bytes requested and returns them
+ * in the fifo segment array. The number of bytes provisioned may be less
+ * than requested if not enough segments were provided.
*
* @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
+ * @param fs array of fifo segments
+ * @param n_segs length of fifo segments array
+ * @param len number of bytes to preallocate
+ * @return number of fifo segments provisioned or error
*/
-int svm_fifo_reduce_size (svm_fifo_t * f, u32 len, u8 try_shrink);
+int svm_fifo_provision_chunks (svm_fifo_t *f, svm_fifo_seg_t *fs, u32 n_segs,
+ u32 len);
/**
- * Removes chunks that are after fifo end byte
+ * Initialize rbtrees used for ooo lookups
*
- * Needs to be called with segment heap pushed.
- *
- * @param f fifo
+ * @param f fifo
+ * @param ooo_type type of ooo operation (0 enqueue, 1 dequeue)
*/
-svm_fifo_chunk_t *svm_fifo_collect_chunks (svm_fifo_t * f);
+void svm_fifo_init_ooo_lookup (svm_fifo_t * f, u8 ooo_type);
/**
* Free fifo and associated state
*
* @param len number of bytes to add to tail
*/
void svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len);
+/**
+ * Enqueue array of @ref svm_fifo_seg_t in order
+ *
+ * @param f fifo
+ * @param segs array of segments to enqueue
+ * @param n_segs number of segments
+ * @param allow_partial if set partial enqueues are allowed
+ * @return len if enqueue was successful, error otherwise
+ */
+int svm_fifo_enqueue_segments (svm_fifo_t * f, const svm_fifo_seg_t segs[],
+ u32 n_segs, u8 allow_partial);
/**
* Overwrite fifo head with new data
*
* This should be typically used by dgram transport protocols that need
- * to update the dgram header after dequeueing a chunk of data. It assumes
+ * to update the dgram header after dequeuing a chunk of data. It assumes
* that the dgram header is at most spread over two chunks.
*
* @param f fifo
* Dequeue data from fifo
*
* Data is dequeued to consumer provided buffer and head is atomically
- * updated.
+ * updated. This should not be used in combination with ooo lookups. If
+ * ooo peeking of data is needed in combination with dequeuing use @ref
+ * svm_fifo_dequeue_drop.
*
* @param f fifo
* @param len length of data to dequeue
* @param f fifo
*/
void svm_fifo_dequeue_drop_all (svm_fifo_t * f);
-int svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs);
-void svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs);
+/**
+ * Get pointers to fifo chunks data in @ref svm_fifo_seg_t array
+ *
+ * Populates fifo segment array with pointers to fifo chunk data and lengths.
+ * Because this returns pointers to data, it must be paired with
+ * @ref svm_fifo_dequeue_drop to actually release the fifo chunks after the
+ * data is consumed.
+ *
+ * @param f fifo
+ * @param offset offset from where to retrieve segments
+ * @param fs array of fifo segments allocated by caller
+ * @param n_segs number of fifo segments in array
+ * @param max_bytes max bytes to be mapped to fifo segments
+ * @return number of bytes in fifo segments or SVM_FIFO_EEMPTY
+ */
+int svm_fifo_segments (svm_fifo_t *f, u32 offset, svm_fifo_seg_t *fs,
+ u32 *n_segs, u32 max_bytes);
/**
* Add io events subscriber to list
*
*/
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.
+ * Number of chunks linked into the fifo
*
- * @param f fifo
- * @return 1 if the fifo is already owned by another thread, 0 otherwise
+ * @param f fifo
+ * @return number of chunks in fifo linked list
*/
-u8 svm_fifo_set_single_thread_owned (svm_fifo_t * f);
+u32 svm_fifo_n_chunks (svm_fifo_t * f);
format_function_t format_svm_fifo;
/**
static inline int
svm_fifo_is_full_prod (svm_fifo_t * f)
{
- return (svm_fifo_max_dequeue_prod (f) == f->nitems);
+ return (svm_fifo_max_dequeue_prod (f) == f->shr->size);
}
/* Check if fifo is full.
static inline int
svm_fifo_is_full (svm_fifo_t * f)
{
- return (svm_fifo_max_dequeue (f) == f->nitems);
+ return (svm_fifo_max_dequeue (f) == f->shr->size);
}
/**
{
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);
}
/**
- * Max contiguous chunk of data that can be read
+ * Max contiguous chunk of data that can be read.
+ *
+ * Should only be called by consumers.
*/
-static inline u32
-svm_fifo_max_read_chunk (svm_fifo_t * f)
-{
- u32 head, tail;
- f_load_head_tail_cons (f, &head, &tail);
- return tail >= head ? (tail - head) : (f->size - head);
-}
+u32 svm_fifo_max_read_chunk (svm_fifo_t * f);
/**
* Max contiguous chunk of data that can be written
+ *
+ * Should only be called by producers
*/
-static inline u32
-svm_fifo_max_write_chunk (svm_fifo_t * f)
-{
- u32 head, tail;
- f_load_head_tail_prod (f, &head, &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->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->tail_chunk->start_byte));
-}
+u32 svm_fifo_max_write_chunk (svm_fifo_t * f);
+/**
+ * Fifo number of subscribers getter
+ *
+ * @param f fifo
+ * @return number of subscribers
+ */
static inline u8
svm_fifo_n_subscribers (svm_fifo_t * f)
{
- return f->n_subscribers;
+ return f->shr->n_subscribers;
}
/**
{
u32 tail;
/* load-relaxed: producer owned index */
- tail = f->tail;
+ tail = f->shr->tail;
- return f_distance_to (f, s->start, tail);
+ return (s->start - tail);
}
static inline u32
return s->length;
}
+static inline u32
+svm_fifo_size (svm_fifo_t * f)
+{
+ return f->shr->size;
+}
+
+static inline void
+svm_fifo_set_size (svm_fifo_t * f, u32 size)
+{
+ if (size > (1 << f->fs_hdr->max_log2_fifo_size))
+ return;
+ fsh_virtual_mem_update (f->fs_hdr, f->shr->slice_index,
+ (int) f->shr->size - size);
+ f->shr->size = size;
+}
+
/**
* Check if fifo has io event
*
static inline int
svm_fifo_has_event (svm_fifo_t * f)
{
- return f->has_event;
+ return f->shr->has_event;
}
/**
always_inline u8
svm_fifo_set_event (svm_fifo_t * f)
{
- return !clib_atomic_swap_rel_n (&f->has_event, 1);
+ return !clib_atomic_swap_rel_n (&f->shr->has_event, 1);
}
/**
always_inline void
svm_fifo_unset_event (svm_fifo_t * f)
{
- clib_atomic_swap_acq_n (&f->has_event, 0);
+ clib_atomic_swap_acq_n (&f->shr->has_event, 0);
}
/**
static inline void
svm_fifo_add_want_deq_ntf (svm_fifo_t * f, u8 ntf_type)
{
- f->want_deq_ntf |= ntf_type;
+ f->shr->want_deq_ntf |= ntf_type;
}
/**
static inline void
svm_fifo_del_want_deq_ntf (svm_fifo_t * f, u8 ntf_type)
{
- f->want_deq_ntf &= ~ntf_type;
+ f->shr->want_deq_ntf &= ~ntf_type;
}
/**
svm_fifo_clear_deq_ntf (svm_fifo_t * f)
{
/* 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;
+ f->shr->has_deq_ntf =
+ f->shr->want_deq_ntf == SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL;
svm_fifo_del_want_deq_ntf (f, SVM_FIFO_WANT_DEQ_NOTIF);
}
static inline void
svm_fifo_reset_has_deq_ntf (svm_fifo_t * f)
{
- f->has_deq_ntf = 0;
+ f->shr->has_deq_ntf = 0;
}
/**
static inline u8
svm_fifo_needs_deq_ntf (svm_fifo_t * f, u32 n_last_deq)
{
- u8 want_ntf = f->want_deq_ntf;
+ u8 want_ntf = f->shr->want_deq_ntf;
if (PREDICT_TRUE (want_ntf == SVM_FIFO_NO_DEQ_NOTIF))
return 0;
else if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF)
- return 1;
+ return (svm_fifo_max_enqueue (f) >= f->shr->deq_thresh);
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_deq_ntf && max_deq < nitems
- && max_deq + n_last_deq >= nitems)
+ u32 size = f->shr->size;
+ if (!f->shr->has_deq_ntf && max_deq < size &&
+ max_deq + n_last_deq >= size)
return 1;
}
if (want_ntf & SVM_FIFO_WANT_DEQ_NOTIF_IF_EMPTY)
{
- if (!f->has_deq_ntf && svm_fifo_is_empty (f))
+ if (!f->shr->has_deq_ntf && svm_fifo_is_empty (f))
return 1;
}
return 0;
}
+/**
+ * Set the fifo dequeue threshold which will be used for notifications.
+ *
+ * Note: If not set, by default threshold is zero, equivalent to
+ * generating notification on each dequeue event.
+ */
+static inline void
+svm_fifo_set_deq_thresh (svm_fifo_t *f, u32 thresh)
+{
+ f->shr->deq_thresh = thresh;
+}
+
#endif /* __included_ssvm_fifo_h__ */
/*