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Vector Packet Processing
svm_fifo.c File Reference
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Functions

 CLIB_MARCH_FN (svm_fifo_copy_to_chunk, void, svm_fifo_t *f, svm_fifo_chunk_t *c, u32 tail_idx, const u8 *src, u32 len, svm_fifo_chunk_t **last)
 
 CLIB_MARCH_FN (svm_fifo_copy_from_chunk, void, svm_fifo_t *f, svm_fifo_chunk_t *c, u32 head_idx, u8 *dst, u32 len, svm_fifo_chunk_t **last)
 
static void svm_fifo_copy_to_chunk (svm_fifo_t *f, svm_fifo_chunk_t *c, u32 tail_idx, const u8 *src, u32 len, svm_fifo_chunk_t **last)
 
static void svm_fifo_copy_from_chunk (svm_fifo_t *f, svm_fifo_chunk_t *c, u32 head_idx, u8 *dst, u32 len, svm_fifo_chunk_t **last)
 
static u32 ooo_segment_end_pos (ooo_segment_t *s)
 
void svm_fifo_free_ooo_data (svm_fifo_t *f)
 Cleanup fifo ooo data. More...
 
static ooo_segment_tooo_segment_prev (svm_fifo_t *f, ooo_segment_t *s)
 
static ooo_segment_tooo_segment_next (svm_fifo_t *f, ooo_segment_t *s)
 
static ooo_segment_tooo_segment_alloc (svm_fifo_t *f, u32 start, u32 length)
 
static void ooo_segment_free (svm_fifo_t *f, u32 index)
 
static void ooo_segment_add (svm_fifo_t *f, u32 offset, u32 head, u32 tail, u32 length)
 Add segment to fifo's out-of-order segment list. More...
 
static int ooo_segment_try_collect (svm_fifo_t *f, u32 n_bytes_enqueued, u32 *tail)
 Removes segments that can now be enqueued because the fifo's tail has advanced. More...
 
static __clib_unused ooo_segment_tooo_segment_last (svm_fifo_t *f)
 
void svm_fifo_init (svm_fifo_t *f, u32 size)
 Initialize fifo. More...
 
void svm_fifo_init_ooo_lookup (svm_fifo_t *f, u8 ooo_type)
 Initialize rbtrees used for ooo lookups. More...
 
svm_fifo_tsvm_fifo_alloc (u32 data_size_in_bytes)
 Creates a fifo in the current heap. More...
 
svm_fifo_chunk_tsvm_fifo_chunk_alloc (u32 size)
 Creates a fifo chunk in the current heap. More...
 
static svm_fifo_chunk_tsvm_fifo_find_chunk (svm_fifo_t *f, u32 pos)
 Find chunk for given byte position. More...
 
static svm_fifo_chunk_tsvm_fifo_find_next_chunk (svm_fifo_t *f, svm_fifo_chunk_t *start, u32 pos)
 
u32 svm_fifo_max_read_chunk (svm_fifo_t *f)
 Max contiguous chunk of data that can be read. More...
 
u32 svm_fifo_max_write_chunk (svm_fifo_t *f)
 Max contiguous chunk of data that can be written. More...
 
static rb_node_tf_find_node_rbtree (rb_tree_t *rt, u32 pos)
 
static svm_fifo_chunk_tf_find_chunk_rbtree (rb_tree_t *rt, u32 pos)
 
static void f_update_ooo_enq (svm_fifo_t *f, u32 start_pos, u32 end_pos)
 
static void f_update_ooo_deq (svm_fifo_t *f, u32 start_pos, u32 end_pos)
 
static svm_fifo_chunk_tf_lookup_clear_enq_chunks (svm_fifo_t *f, svm_fifo_chunk_t *start, u32 end_pos)
 
static svm_fifo_chunk_tf_lookup_clear_deq_chunks (svm_fifo_t *f, svm_fifo_chunk_t *start, u32 end_pos)
 
void svm_fifo_free_chunk_lookup (svm_fifo_t *f)
 Cleanup fifo chunk lookup rb tree. More...
 
void svm_fifo_free (svm_fifo_t *f)
 Free fifo and associated state. More...
 
void svm_fifo_overwrite_head (svm_fifo_t *f, u8 *src, u32 len)
 Overwrite fifo head with new data. More...
 
static int f_try_chunk_alloc (svm_fifo_t *f, u32 head, u32 tail, u32 len)
 
int svm_fifo_enqueue (svm_fifo_t *f, u32 len, const u8 *src)
 Enqueue data to fifo. More...
 
int svm_fifo_enqueue_with_offset (svm_fifo_t *f, u32 offset, u32 len, u8 *src)
 Enqueue a future segment. More...
 
void svm_fifo_enqueue_nocopy (svm_fifo_t *f, u32 len)
 Advance tail. More...
 
int svm_fifo_enqueue_segments (svm_fifo_t *f, const svm_fifo_seg_t segs[], u32 n_segs, u8 allow_partial)
 Enqueue array of svm_fifo_seg_t in order. More...
 
static svm_fifo_chunk_tf_unlink_chunks (svm_fifo_t *f, u32 end_pos, u8 maybe_ooo)
 
int svm_fifo_dequeue (svm_fifo_t *f, u32 len, u8 *dst)
 Dequeue data from fifo. More...
 
int svm_fifo_peek (svm_fifo_t *f, u32 offset, u32 len, u8 *dst)
 Peek data from fifo. More...
 
int svm_fifo_dequeue_drop (svm_fifo_t *f, u32 len)
 Dequeue and drop bytes from fifo. More...
 
void svm_fifo_dequeue_drop_all (svm_fifo_t *f)
 Drop all data from fifo. More...
 
int svm_fifo_fill_chunk_list (svm_fifo_t *f)
 Ensure the whole fifo size is writeable. More...
 
int svm_fifo_segments (svm_fifo_t *f, u32 offset, svm_fifo_seg_t *fs, u32 n_segs, u32 max_bytes)
 Get pointers to fifo chunks data in svm_fifo_seg_t array. More...
 
void svm_fifo_clone (svm_fifo_t *df, svm_fifo_t *sf)
 Clones fifo. More...
 
u32 svm_fifo_n_ooo_segments (svm_fifo_t *f)
 Number of out-of-order segments for fifo. More...
 
ooo_segment_tsvm_fifo_first_ooo_segment (svm_fifo_t *f)
 First out-of-order segment for fifo. More...
 
void svm_fifo_init_pointers (svm_fifo_t *f, u32 head, u32 tail)
 Set fifo pointers to requested offset. More...
 
void svm_fifo_add_subscriber (svm_fifo_t *f, u8 subscriber)
 Add io events subscriber to list. More...
 
void svm_fifo_del_subscriber (svm_fifo_t *f, u8 subscriber)
 Remove io events subscriber form list. More...
 
u8 svm_fifo_is_sane (svm_fifo_t *f)
 Check if fifo is sane. More...
 
u32 svm_fifo_n_chunks (svm_fifo_t *f)
 Number of chunks linked into the fifo. More...
 
u8format_ooo_segment (u8 *s, va_list *args)
 
u8svm_fifo_dump_trace (u8 *s, svm_fifo_t *f)
 
u8svm_fifo_replay (u8 *s, svm_fifo_t *f, u8 no_read, u8 verbose)
 
u8format_ooo_list (u8 *s, va_list *args)
 
u8format_svm_fifo (u8 *s, va_list *args)
 

Function Documentation

◆ CLIB_MARCH_FN() [1/2]

CLIB_MARCH_FN ( svm_fifo_copy_to_chunk  ,
void  ,
svm_fifo_t f,
svm_fifo_chunk_t c,
u32  tail_idx,
const u8 src,
u32  len,
svm_fifo_chunk_t **  last 
)

Definition at line 24 of file svm_fifo.c.

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◆ CLIB_MARCH_FN() [2/2]

CLIB_MARCH_FN ( svm_fifo_copy_from_chunk  ,
void  ,
svm_fifo_t f,
svm_fifo_chunk_t c,
u32  head_idx,
u8 dst,
u32  len,
svm_fifo_chunk_t **  last 
)

Definition at line 55 of file svm_fifo.c.

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◆ f_find_chunk_rbtree()

static svm_fifo_chunk_t* f_find_chunk_rbtree ( rb_tree_t rt,
u32  pos 
)
static

Definition at line 580 of file svm_fifo.c.

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◆ f_find_node_rbtree()

static rb_node_t* f_find_node_rbtree ( rb_tree_t rt,
u32  pos 
)
static

Definition at line 542 of file svm_fifo.c.

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◆ f_lookup_clear_deq_chunks()

static svm_fifo_chunk_t* f_lookup_clear_deq_chunks ( svm_fifo_t f,
svm_fifo_chunk_t start,
u32  end_pos 
)
static

Definition at line 731 of file svm_fifo.c.

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◆ f_lookup_clear_enq_chunks()

static svm_fifo_chunk_t* f_lookup_clear_enq_chunks ( svm_fifo_t f,
svm_fifo_chunk_t start,
u32  end_pos 
)
static

Definition at line 697 of file svm_fifo.c.

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◆ f_try_chunk_alloc()

static int f_try_chunk_alloc ( svm_fifo_t f,
u32  head,
u32  tail,
u32  len 
)
static

Definition at line 802 of file svm_fifo.c.

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◆ f_unlink_chunks()

static svm_fifo_chunk_t* f_unlink_chunks ( svm_fifo_t f,
u32  end_pos,
u8  maybe_ooo 
)
inlinestatic

Definition at line 1040 of file svm_fifo.c.

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◆ f_update_ooo_deq()

static void f_update_ooo_deq ( svm_fifo_t f,
u32  start_pos,
u32  end_pos 
)
static

Definition at line 648 of file svm_fifo.c.

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◆ f_update_ooo_enq()

static void f_update_ooo_enq ( svm_fifo_t f,
u32  start_pos,
u32  end_pos 
)
static

Definition at line 599 of file svm_fifo.c.

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◆ format_ooo_list()

u8* format_ooo_list ( u8 s,
va_list *  args 
)

Definition at line 1551 of file svm_fifo.c.

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◆ format_ooo_segment()

u8* format_ooo_segment ( u8 s,
va_list *  args 
)

Definition at line 1458 of file svm_fifo.c.

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◆ format_svm_fifo()

u8* format_svm_fifo ( u8 s,
va_list *  args 
)

Definition at line 1570 of file svm_fifo.c.

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◆ ooo_segment_add()

static void ooo_segment_add ( svm_fifo_t f,
u32  offset,
u32  head,
u32  tail,
u32  length 
)
static

Add segment to fifo's out-of-order segment list.

Takes care of merging adjacent segments and removing overlapping ones.

Definition at line 178 of file svm_fifo.c.

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◆ ooo_segment_alloc()

static ooo_segment_t* ooo_segment_alloc ( svm_fifo_t f,
u32  start,
u32  length 
)
inlinestatic

Definition at line 135 of file svm_fifo.c.

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◆ ooo_segment_end_pos()

static u32 ooo_segment_end_pos ( ooo_segment_t s)
inlinestatic

Definition at line 107 of file svm_fifo.c.

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◆ ooo_segment_free()

static void ooo_segment_free ( svm_fifo_t f,
u32  index 
)
inlinestatic

Definition at line 149 of file svm_fifo.c.

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◆ ooo_segment_last()

static __clib_unused ooo_segment_t* ooo_segment_last ( svm_fifo_t f)
static

Definition at line 356 of file svm_fifo.c.

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◆ ooo_segment_next()

static ooo_segment_t* ooo_segment_next ( svm_fifo_t f,
ooo_segment_t s 
)
inlinestatic

Definition at line 127 of file svm_fifo.c.

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◆ ooo_segment_prev()

static ooo_segment_t* ooo_segment_prev ( svm_fifo_t f,
ooo_segment_t s 
)
inlinestatic

Definition at line 119 of file svm_fifo.c.

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◆ ooo_segment_try_collect()

static int ooo_segment_try_collect ( svm_fifo_t f,
u32  n_bytes_enqueued,
u32 tail 
)
static

Removes segments that can now be enqueued because the fifo's tail has advanced.

Returns the number of bytes added to tail.

Definition at line 308 of file svm_fifo.c.

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◆ svm_fifo_add_subscriber()

void svm_fifo_add_subscriber ( svm_fifo_t f,
u8  sub 
)

Add io events subscriber to list.

Parameters
ffifo
subsubscriber opaque index (typically app worker index)

Definition at line 1326 of file svm_fifo.c.

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◆ svm_fifo_alloc()

svm_fifo_t* svm_fifo_alloc ( u32  data_size_in_bytes)

Creates a fifo in the current heap.

Create fifo of requested size.

Fails vs blow up the process

Definition at line 423 of file svm_fifo.c.

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◆ svm_fifo_chunk_alloc()

svm_fifo_chunk_t* svm_fifo_chunk_alloc ( u32  size)

Creates a fifo chunk in the current heap.

Allocate a fifo chunk on heap.

Definition at line 459 of file svm_fifo.c.

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◆ svm_fifo_clone()

void svm_fifo_clone ( svm_fifo_t df,
svm_fifo_t sf 
)

Clones fifo.

Clone fifo.

Assumptions:

  • no prod and cons are accessing either dest or src fifo
  • fifo is not multi chunk

Definition at line 1280 of file svm_fifo.c.

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◆ svm_fifo_copy_from_chunk()

static void svm_fifo_copy_from_chunk ( svm_fifo_t f,
svm_fifo_chunk_t c,
u32  head_idx,
u8 dst,
u32  len,
svm_fifo_chunk_t **  last 
)
inlinestatic

Definition at line 99 of file svm_fifo.c.

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◆ svm_fifo_copy_to_chunk()

static void svm_fifo_copy_to_chunk ( svm_fifo_t f,
svm_fifo_chunk_t c,
u32  tail_idx,
const u8 src,
u32  len,
svm_fifo_chunk_t **  last 
)
inlinestatic

Definition at line 91 of file svm_fifo.c.

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◆ svm_fifo_del_subscriber()

void svm_fifo_del_subscriber ( svm_fifo_t f,
u8  subscriber 
)

Remove io events subscriber form list.

Parameters
ffifo
subsubscriber index to be removed

Definition at line 1334 of file svm_fifo.c.

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◆ svm_fifo_dequeue()

int svm_fifo_dequeue ( svm_fifo_t f,
u32  len,
u8 dst 
)

Dequeue data from fifo.

Data is dequeued to consumer provided buffer and head is atomically updated. This should not be used in combination with ooo lookups. If ooo peeking of data is needed in combination with dequeuing use svm_fifo_dequeue_drop.

Parameters
ffifo
lenlength of data to dequeue
dstbuffer to where to dequeue the data
Returns
number of bytes dequeued or error

Definition at line 1092 of file svm_fifo.c.

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◆ svm_fifo_dequeue_drop()

int svm_fifo_dequeue_drop ( svm_fifo_t f,
u32  len 
)

Dequeue and drop bytes from fifo.

Advances fifo head by requested amount of bytes.

Parameters
ffifo
lennumber of bytes to drop
Returns
number of bytes dropped

Definition at line 1151 of file svm_fifo.c.

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◆ svm_fifo_dequeue_drop_all()

void svm_fifo_dequeue_drop_all ( svm_fifo_t f)

Drop all data from fifo.

Dequeue and drop all bytes from fifo.

Definition at line 1189 of file svm_fifo.c.

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◆ svm_fifo_dump_trace()

u8* svm_fifo_dump_trace ( u8 s,
svm_fifo_t f 
)

Definition at line 1468 of file svm_fifo.c.

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◆ svm_fifo_enqueue()

int svm_fifo_enqueue ( svm_fifo_t f,
u32  len,
const u8 src 
)

Enqueue data to fifo.

Data is enqueued and tail pointer is updated atomically. If the new data enqueued partly overlaps or "touches" an out-of-order segment, said segment is "consumed" and the number of bytes returned is appropriately updated.

Parameters
ffifo
lenlength of data to copy
srcbuffer from where to copy the data
Returns
number of contiguous bytes that can be consumed or error

Definition at line 840 of file svm_fifo.c.

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◆ svm_fifo_enqueue_nocopy()

void svm_fifo_enqueue_nocopy ( svm_fifo_t f,
u32  len 
)

Advance tail.

Advance tail pointer.

Definition at line 935 of file svm_fifo.c.

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◆ svm_fifo_enqueue_segments()

int svm_fifo_enqueue_segments ( svm_fifo_t f,
const svm_fifo_seg_t  segs[],
u32  n_segs,
u8  allow_partial 
)

Enqueue array of svm_fifo_seg_t in order.

Parameters
ffifo
segsarray of segments to enqueue
n_segsnumber of segments
allow_partialif set partial enqueues are allowed
Returns
len if enqueue was successful, error otherwise

Definition at line 959 of file svm_fifo.c.

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◆ svm_fifo_enqueue_with_offset()

int svm_fifo_enqueue_with_offset ( svm_fifo_t f,
u32  offset,
u32  len,
u8 src 
)

Enqueue a future segment.

Enqueue data to fifo with offset.

Two choices: either copies the entire segment, or copies nothing Returns 0 of the entire segment was copied Returns -1 if none of the segment was copied due to lack of space

Definition at line 898 of file svm_fifo.c.

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◆ svm_fifo_fill_chunk_list()

int svm_fifo_fill_chunk_list ( svm_fifo_t f)

Ensure the whole fifo size is writeable.

Allocates enough chunks to cover the whole fifo size.

Parameters
ffifo

Definition at line 1209 of file svm_fifo.c.

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◆ svm_fifo_find_chunk()

static svm_fifo_chunk_t* svm_fifo_find_chunk ( svm_fifo_t f,
u32  pos 
)
static

Find chunk for given byte position.

Parameters
ffifo
posnormalized position in fifo
Returns
chunk that includes given position or 0

Definition at line 485 of file svm_fifo.c.

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◆ svm_fifo_find_next_chunk()

static svm_fifo_chunk_t* svm_fifo_find_next_chunk ( svm_fifo_t f,
svm_fifo_chunk_t start,
u32  pos 
)
static

Definition at line 497 of file svm_fifo.c.

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◆ svm_fifo_first_ooo_segment()

ooo_segment_t* svm_fifo_first_ooo_segment ( svm_fifo_t f)

First out-of-order segment for fifo.

Parameters
ffifo
Returns
first out-of-order segment for fifo

Definition at line 1301 of file svm_fifo.c.

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◆ svm_fifo_free()

void svm_fifo_free ( svm_fifo_t f)

Free fifo and associated state.

Parameters
ffifo

Definition at line 762 of file svm_fifo.c.

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◆ svm_fifo_free_chunk_lookup()

void svm_fifo_free_chunk_lookup ( svm_fifo_t f)

Cleanup fifo chunk lookup rb tree.

The rb tree is allocated in segment heap so this should be called with it pushed.

Parameters
ffifo to cleanup

Definition at line 755 of file svm_fifo.c.

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◆ svm_fifo_free_ooo_data()

void svm_fifo_free_ooo_data ( svm_fifo_t f)

Cleanup fifo ooo data.

The ooo data is allocated in producer process memory. The fifo segment heap should not be pushed.

Parameters
ffifo to cleanup

Definition at line 113 of file svm_fifo.c.

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◆ svm_fifo_init()

void svm_fifo_init ( svm_fifo_t f,
u32  size 
)

Initialize fifo.

Parameters
ffifo
sizesize for fifo

Definition at line 370 of file svm_fifo.c.

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◆ svm_fifo_init_ooo_lookup()

void svm_fifo_init_ooo_lookup ( svm_fifo_t f,
u8  ooo_type 
)

Initialize rbtrees used for ooo lookups.

Parameters
ffifo
ooo_typetype of ooo operation (0 enqueue, 1 dequeue)

Definition at line 405 of file svm_fifo.c.

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◆ svm_fifo_init_pointers()

void svm_fifo_init_pointers ( svm_fifo_t f,
u32  head,
u32  tail 
)

Set fifo pointers to requested offset.

Init fifo head and tail.

Definition at line 1310 of file svm_fifo.c.

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◆ svm_fifo_is_sane()

u8 svm_fifo_is_sane ( svm_fifo_t f)

Check if fifo is sane.

Debug only.

Parameters
ffifo
Returns
1 if sane, 0 otherwise

Definition at line 1349 of file svm_fifo.c.

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◆ svm_fifo_max_read_chunk()

u32 svm_fifo_max_read_chunk ( svm_fifo_t f)

Max contiguous chunk of data that can be read.

Should only be called by consumers.

Definition at line 511 of file svm_fifo.c.

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◆ svm_fifo_max_write_chunk()

u32 svm_fifo_max_write_chunk ( svm_fifo_t f)

Max contiguous chunk of data that can be written.

Should only be called by producers

Definition at line 531 of file svm_fifo.c.

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◆ svm_fifo_n_chunks()

u32 svm_fifo_n_chunks ( svm_fifo_t f)

Number of chunks linked into the fifo.

Parameters
ffifo
Returns
number of chunks in fifo linked list

Definition at line 1442 of file svm_fifo.c.

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◆ svm_fifo_n_ooo_segments()

u32 svm_fifo_n_ooo_segments ( svm_fifo_t f)

Number of out-of-order segments for fifo.

Parameters
ffifo
Returns
number of out of order segments

Definition at line 1295 of file svm_fifo.c.

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◆ svm_fifo_overwrite_head()

void svm_fifo_overwrite_head ( svm_fifo_t f,
u8 src,
u32  len 
)

Overwrite fifo head with new data.

This should be typically used by dgram transport protocols that need to update the dgram header after dequeuing a chunk of data. It assumes that the dgram header is at most spread over two chunks.

Parameters
ffifo
srcsrc of new data
lenlength of new data

Definition at line 775 of file svm_fifo.c.

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◆ svm_fifo_peek()

int svm_fifo_peek ( svm_fifo_t f,
u32  offset,
u32  len,
u8 dst 
)

Peek data from fifo.

Data is copied from requested offset into provided dst buffer. Head is not updated.

Parameters
ffifo
offsetoffset from which to copy the data
lenlength of data to copy
dstbuffer to where to dequeue the data
Returns
number of bytes peeked

Definition at line 1127 of file svm_fifo.c.

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◆ svm_fifo_replay()

u8* svm_fifo_replay ( u8 s,
svm_fifo_t f,
u8  no_read,
u8  verbose 
)

Definition at line 1492 of file svm_fifo.c.

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◆ svm_fifo_segments()

int svm_fifo_segments ( svm_fifo_t f,
u32  offset,
svm_fifo_seg_t fs,
u32  n_segs,
u32  max_bytes 
)

Get pointers to fifo chunks data in 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 svm_fifo_dequeue_drop to actually release the fifo chunks after the data is consumed.

Parameters
ffifo
offsetoffset from where to retrieve segments
fsarray of fifo segments allocated by caller
n_segsnumber of fifo segments in array
max_bytesmax bytes to be mapped to fifo segments
Returns
number of bytes in fifo segments or SVM_FIFO_EEMPTY

Definition at line 1225 of file svm_fifo.c.

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