blob: fda9481e72161b5a668a96cbe50203fd761f2707 [file] [log] [blame]
/*
* Copyright (c) 2016-2019 Cisco and/or its affiliates.
* Copyright (c) 2019 Arm Limited
* Copyright (c) 2010-2017 Intel Corporation and/or its affiliates.
* Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org
* Inspired from DPDK rte_ring.h (SPSC only) (derived from freebsd bufring.h).
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <svm/svm_fifo.h>
#include <svm/fifo_segment.h>
#include <vppinfra/cpu.h>
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)
{
u32 n_chunk;
ASSERT (f_pos_geq (tail_idx, c->start_byte)
&& f_pos_lt (tail_idx, c->start_byte + c->length));
tail_idx -= c->start_byte;
n_chunk = c->length - tail_idx;
if (n_chunk <= len)
{
u32 to_copy = len;
clib_memcpy_fast (&c->data[tail_idx], src, n_chunk);
c = c->next;
while ((to_copy -= n_chunk))
{
n_chunk = clib_min (c->length, to_copy);
clib_memcpy_fast (&c->data[0], src + (len - to_copy), n_chunk);
c = c->length <= to_copy ? c->next : c;
}
if (*last)
*last = c;
}
else
{
clib_memcpy_fast (&c->data[tail_idx], src, len);
}
}
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)
{
u32 n_chunk;
ASSERT (f_pos_geq (head_idx, c->start_byte)
&& f_pos_lt (head_idx, c->start_byte + c->length));
head_idx -= c->start_byte;
n_chunk = c->length - head_idx;
if (n_chunk <= len)
{
u32 to_copy = len;
clib_memcpy_fast (dst, &c->data[head_idx], n_chunk);
c = c->next;
while ((to_copy -= n_chunk))
{
n_chunk = clib_min (c->length, to_copy);
clib_memcpy_fast (dst + (len - to_copy), &c->data[0], n_chunk);
c = c->length <= to_copy ? c->next : c;
}
if (*last)
*last = c;
}
else
{
clib_memcpy_fast (dst, &c->data[head_idx], len);
}
}
#ifndef CLIB_MARCH_VARIANT
static inline 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)
{
CLIB_MARCH_FN_SELECT (svm_fifo_copy_to_chunk) (f, c, tail_idx, src, len,
last);
}
static inline 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)
{
CLIB_MARCH_FN_SELECT (svm_fifo_copy_from_chunk) (f, c, head_idx, dst, len,
last);
}
static inline u32
ooo_segment_end_pos (ooo_segment_t * s)
{
return (s->start + s->length);
}
void
svm_fifo_free_ooo_data (svm_fifo_t * f)
{
pool_free (f->ooo_segments);
}
static inline ooo_segment_t *
ooo_segment_prev (svm_fifo_t * f, ooo_segment_t * s)
{
if (s->prev == OOO_SEGMENT_INVALID_INDEX)
return 0;
return pool_elt_at_index (f->ooo_segments, s->prev);
}
static inline ooo_segment_t *
ooo_segment_next (svm_fifo_t * f, ooo_segment_t * s)
{
if (s->next == OOO_SEGMENT_INVALID_INDEX)
return 0;
return pool_elt_at_index (f->ooo_segments, s->next);
}
static inline ooo_segment_t *
ooo_segment_alloc (svm_fifo_t * f, u32 start, u32 length)
{
ooo_segment_t *s;
pool_get (f->ooo_segments, s);
s->start = start;
s->length = length;
s->prev = s->next = OOO_SEGMENT_INVALID_INDEX;
return s;
}
static inline void
ooo_segment_free (svm_fifo_t * f, u32 index)
{
ooo_segment_t *cur, *prev = 0, *next = 0;
cur = pool_elt_at_index (f->ooo_segments, index);
if (cur->next != OOO_SEGMENT_INVALID_INDEX)
{
next = pool_elt_at_index (f->ooo_segments, cur->next);
next->prev = cur->prev;
}
if (cur->prev != OOO_SEGMENT_INVALID_INDEX)
{
prev = pool_elt_at_index (f->ooo_segments, cur->prev);
prev->next = cur->next;
}
else
{
f->ooos_list_head = cur->next;
}
pool_put (f->ooo_segments, cur);
}
/**
* Add segment to fifo's out-of-order segment list. Takes care of merging
* adjacent segments and removing overlapping ones.
*/
static void
ooo_segment_add (svm_fifo_t * f, u32 offset, u32 head, u32 tail, u32 length)
{
ooo_segment_t *s, *new_s, *prev, *next, *it;
u32 new_index, s_end_pos, s_index;
u32 offset_pos, offset_end_pos;
ASSERT (offset + length <= f_free_count (f, head, tail));
offset_pos = tail + offset;
offset_end_pos = tail + offset + length;
f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
{
s = ooo_segment_alloc (f, offset_pos, length);
f->ooos_list_head = s - f->ooo_segments;
f->ooos_newest = f->ooos_list_head;
return;
}
/* Find first segment that starts after new segment */
s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
while (s->next != OOO_SEGMENT_INVALID_INDEX
&& f_pos_lt (s->start, offset_pos))
s = pool_elt_at_index (f->ooo_segments, s->next);
/* If we have a previous and we overlap it, use it as starting point */
prev = ooo_segment_prev (f, s);
if (prev && f_pos_leq (offset_pos, ooo_segment_end_pos (prev)))
{
s = prev;
s_end_pos = ooo_segment_end_pos (s);
/* Since we have previous, offset start position cannot be smaller
* than prev->start. Check tail */
ASSERT (f_pos_lt (s->start, offset_pos));
goto check_tail;
}
s_index = s - f->ooo_segments;
s_end_pos = ooo_segment_end_pos (s);
/* No overlap, add before current segment */
if (f_pos_lt (offset_end_pos, s->start))
{
new_s = ooo_segment_alloc (f, offset_pos, length);
new_index = new_s - f->ooo_segments;
/* Pool might've moved, get segment again */
s = pool_elt_at_index (f->ooo_segments, s_index);
if (s->prev != OOO_SEGMENT_INVALID_INDEX)
{
new_s->prev = s->prev;
prev = pool_elt_at_index (f->ooo_segments, new_s->prev);
prev->next = new_index;
}
else
{
/* New head */
f->ooos_list_head = new_index;
}
new_s->next = s_index;
s->prev = new_index;
f->ooos_newest = new_index;
return;
}
/* No overlap, add after current segment */
else if (f_pos_gt (offset_pos, s_end_pos))
{
new_s = ooo_segment_alloc (f, offset_pos, length);
new_index = new_s - f->ooo_segments;
/* Pool might've moved, get segment again */
s = pool_elt_at_index (f->ooo_segments, s_index);
/* Needs to be last */
ASSERT (s->next == OOO_SEGMENT_INVALID_INDEX);
new_s->prev = s_index;
s->next = new_index;
f->ooos_newest = new_index;
return;
}
/*
* Merge needed
*/
/* Merge at head */
if (f_pos_lt (offset_pos, s->start))
{
s->start = offset_pos;
s->length = s_end_pos - s->start;
f->ooos_newest = s - f->ooo_segments;
}
check_tail:
/* Overlapping tail */
if (f_pos_gt (offset_end_pos, s_end_pos))
{
s->length = offset_end_pos - s->start;
/* Remove the completely overlapped segments in the tail */
it = ooo_segment_next (f, s);
while (it && f_pos_leq (ooo_segment_end_pos (it), offset_end_pos))
{
next = ooo_segment_next (f, it);
ooo_segment_free (f, it - f->ooo_segments);
it = next;
}
/* If partial overlap with last, merge */
if (it && f_pos_leq (it->start, offset_end_pos))
{
s->length = ooo_segment_end_pos (it) - s->start;
ooo_segment_free (f, it - f->ooo_segments);
}
f->ooos_newest = s - f->ooo_segments;
}
}
/**
* Removes segments that can now be enqueued because the fifo's tail has
* advanced. Returns the number of bytes added to tail.
*/
static int
ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail)
{
u32 s_index, bytes = 0;
ooo_segment_t *s;
i32 diff;
s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
diff = *tail - s->start;
ASSERT (diff != n_bytes_enqueued);
if (diff > n_bytes_enqueued)
return 0;
/* If last tail update overlaps one/multiple ooo segments, remove them */
while (0 <= diff && diff < n_bytes_enqueued)
{
s_index = s - f->ooo_segments;
/* Segment end is beyond the tail. Advance tail and remove segment */
if (s->length > diff)
{
bytes = s->length - diff;
*tail = *tail + bytes;
ooo_segment_free (f, s_index);
break;
}
/* If we have next go on */
if (s->next != OOO_SEGMENT_INVALID_INDEX)
{
s = pool_elt_at_index (f->ooo_segments, s->next);
diff = *tail - s->start;
ooo_segment_free (f, s_index);
}
/* End of search */
else
{
ooo_segment_free (f, s_index);
break;
}
}
ASSERT (bytes <= f->size);
return bytes;
}
__clib_unused static ooo_segment_t *
ooo_segment_last (svm_fifo_t * f)
{
ooo_segment_t *s;
if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
return 0;
s = svm_fifo_first_ooo_segment (f);
while (s->next != OOO_SEGMENT_INVALID_INDEX)
s = pool_elt_at_index (f->ooo_segments, s->next);
return s;
}
void
svm_fifo_init (svm_fifo_t * f, u32 size)
{
svm_fifo_chunk_t *c, *prev;
u32 min_alloc;
f->size = size;
f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
f->segment_index = SVM_FIFO_INVALID_INDEX;
f->refcnt = 1;
f->head = f->tail = f->flags = 0;
f->head_chunk = f->tail_chunk = f->start_chunk;
f->ooo_deq = f->ooo_enq = 0;
min_alloc = size > 32 << 10 ? size >> 3 : 4096;
min_alloc = clib_min (min_alloc, 64 << 10);
f->min_alloc = min_alloc;
/*
* Initialize chunks
*/
f->start_chunk->start_byte = 0;
prev = f->start_chunk;
c = prev->next;
while (c)
{
c->start_byte = prev->start_byte + prev->length;
prev = c;
c = c->next;
}
}
void
svm_fifo_init_ooo_lookup (svm_fifo_t * f, u8 ooo_type)
{
if (ooo_type == 0)
{
ASSERT (!rb_tree_is_init (&f->ooo_enq_lookup));
rb_tree_init (&f->ooo_enq_lookup);
}
else
{
ASSERT (!rb_tree_is_init (&f->ooo_deq_lookup));
rb_tree_init (&f->ooo_deq_lookup);
}
}
/**
* Creates a fifo in the current heap. Fails vs blow up the process
*/
svm_fifo_t *
svm_fifo_alloc (u32 data_size_in_bytes)
{
u32 rounded_data_size;
svm_fifo_chunk_t *c;
svm_fifo_t *f;
f = clib_mem_alloc_aligned_or_null (sizeof (*f), CLIB_CACHE_LINE_BYTES);
if (f == 0)
return 0;
clib_memset (f, 0, sizeof (*f));
/* always round fifo data size to the next highest power-of-two */
rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_data_size,
CLIB_CACHE_LINE_BYTES);
if (!c)
{
clib_mem_free (f);
return 0;
}
clib_memset (c, 0, sizeof (*c));
c->start_byte = 0;
c->length = data_size_in_bytes;
c->enq_rb_index = RBTREE_TNIL_INDEX;
c->deq_rb_index = RBTREE_TNIL_INDEX;
f->start_chunk = f->end_chunk = c;
return f;
}
/**
* Creates a fifo chunk in the current heap
*/
svm_fifo_chunk_t *
svm_fifo_chunk_alloc (u32 size)
{
svm_fifo_chunk_t *c;
u32 rounded_size;
/* round chunk size to the next highest power-of-two */
rounded_size = (1 << (max_log2 (size)));
c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_size,
CLIB_CACHE_LINE_BYTES);
if (c == 0)
return 0;
clib_memset (c, 0, sizeof (*c));
c->length = rounded_size;
return c;
}
/**
* Find chunk for given byte position
*
* @param f fifo
* @param pos normalized position in fifo
*
* @return chunk that includes given position or 0
*/
static svm_fifo_chunk_t *
svm_fifo_find_chunk (svm_fifo_t * f, u32 pos)
{
svm_fifo_chunk_t *c;
c = f->start_chunk;
while (c && !f_chunk_includes_pos (c, pos))
c = c->next;
return c;
}
static svm_fifo_chunk_t *
svm_fifo_find_next_chunk (svm_fifo_t * f, svm_fifo_chunk_t * start, u32 pos)
{
svm_fifo_chunk_t *c;
ASSERT (start != 0);
c = start;
while (c && !f_chunk_includes_pos (c, pos))
c = c->next;
return c;
}
u32
svm_fifo_max_read_chunk (svm_fifo_t * f)
{
u32 head, tail, end_chunk;
f_load_head_tail_cons (f, &head, &tail);
ASSERT (!f->head_chunk || f_chunk_includes_pos (f->head_chunk, head));
if (!f->head_chunk)
{
f->head_chunk = svm_fifo_find_chunk (f, head);
if (PREDICT_FALSE (!f->head_chunk))
return 0;
}
end_chunk = f_chunk_end (f->head_chunk);
return f_pos_lt (end_chunk, tail) ? end_chunk - head : tail - head;
}
u32
svm_fifo_max_write_chunk (svm_fifo_t * f)
{
u32 head, tail;
f_load_head_tail_prod (f, &head, &tail);
ASSERT (!f->tail_chunk || f_chunk_includes_pos (f->tail_chunk, tail));
return f->tail_chunk ? f_chunk_end (f->tail_chunk) - tail : 0;
}
static rb_node_t *
f_find_node_rbtree (rb_tree_t * rt, u32 pos)
{
rb_node_t *cur, *prev;
cur = rb_node (rt, rt->root);
if (PREDICT_FALSE (rb_node_is_tnil (rt, cur)))
return 0;
while (pos != cur->key)
{
prev = cur;
if (f_pos_lt (pos, cur->key))
{
cur = rb_node_left (rt, cur);
if (rb_node_is_tnil (rt, cur))
{
cur = rb_tree_predecessor (rt, prev);
break;
}
}
else
{
cur = rb_node_right (rt, cur);
if (rb_node_is_tnil (rt, cur))
{
cur = prev;
break;
}
}
}
if (rb_node_is_tnil (rt, cur))
return 0;
return cur;
}
static svm_fifo_chunk_t *
f_find_chunk_rbtree (rb_tree_t * rt, u32 pos)
{
svm_fifo_chunk_t *c;
rb_node_t *n;
if (!rb_tree_is_init (rt))
return 0;
n = f_find_node_rbtree (rt, pos);
if (!n)
return 0;
c = uword_to_pointer (n->opaque, svm_fifo_chunk_t *);
if (f_chunk_includes_pos (c, pos))
return c;
return 0;
}
static void
f_update_ooo_enq (svm_fifo_t * f, u32 start_pos, u32 end_pos)
{
rb_tree_t *rt = &f->ooo_enq_lookup;
svm_fifo_chunk_t *c;
rb_node_t *cur;
/* Use linear search if rbtree is not initialized */
if (PREDICT_FALSE (!rb_tree_is_init (rt)))
{
f->ooo_enq = svm_fifo_find_next_chunk (f, f->tail_chunk, start_pos);
return;
}
if (rt->root == RBTREE_TNIL_INDEX)
{
c = f->tail_chunk;
ASSERT (c->enq_rb_index == RBTREE_TNIL_INDEX);
c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte,
pointer_to_uword (c), f_pos_lt);
}
else
{
cur = f_find_node_rbtree (rt, start_pos);
c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
ASSERT (f_pos_leq (c->start_byte, start_pos));
}
if (f_chunk_includes_pos (c, start_pos))
f->ooo_enq = c;
if (f_chunk_includes_pos (c, end_pos))
return;
do
{
c = c->next;
if (!c || c->enq_rb_index != RBTREE_TNIL_INDEX)
break;
c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte,
pointer_to_uword (c), f_pos_lt);
if (f_chunk_includes_pos (c, start_pos))
f->ooo_enq = c;
}
while (!f_chunk_includes_pos (c, end_pos));
}
static void
f_update_ooo_deq (svm_fifo_t * f, u32 start_pos, u32 end_pos)
{
rb_tree_t *rt = &f->ooo_deq_lookup;
rb_node_t *cur;
svm_fifo_chunk_t *c;
/* Use linear search if rbtree is not initialized */
if (PREDICT_FALSE (!rb_tree_is_init (rt)))
{
f->ooo_deq = svm_fifo_find_chunk (f, start_pos);
return;
}
if (rt->root == RBTREE_TNIL_INDEX)
{
c = f->start_chunk;
ASSERT (c->deq_rb_index == RBTREE_TNIL_INDEX);
c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte,
pointer_to_uword (c), f_pos_lt);
}
else
{
cur = f_find_node_rbtree (rt, start_pos);
c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
ASSERT (f_pos_leq (c->start_byte, start_pos));
}
if (f_chunk_includes_pos (c, start_pos))
f->ooo_deq = c;
if (f_chunk_includes_pos (c, end_pos))
return;
do
{
c = c->next;
if (!c || c->deq_rb_index != RBTREE_TNIL_INDEX)
break;
c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte,
pointer_to_uword (c), f_pos_lt);
if (f_chunk_includes_pos (c, start_pos))
f->ooo_deq = c;
}
while (!f_chunk_includes_pos (c, end_pos));
}
static svm_fifo_chunk_t *
f_lookup_clear_enq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start,
u32 end_pos)
{
rb_tree_t *rt = &f->ooo_enq_lookup;
svm_fifo_chunk_t *c;
rb_node_t *n;
c = start;
while (c && !f_chunk_includes_pos (c, end_pos))
{
if (c->enq_rb_index != RBTREE_TNIL_INDEX)
{
n = rb_node (rt, c->enq_rb_index);
rb_tree_del_node (rt, n);
c->enq_rb_index = RBTREE_TNIL_INDEX;
}
c = c->next;
}
/* No ooo segments left, so make sure the current chunk
* is not tracked in the enq rbtree */
if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX
&& c && c->enq_rb_index != RBTREE_TNIL_INDEX)
{
n = rb_node (rt, c->enq_rb_index);
rb_tree_del_node (rt, n);
c->enq_rb_index = RBTREE_TNIL_INDEX;
}
return c;
}
static svm_fifo_chunk_t *
f_lookup_clear_deq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start,
u32 end_pos)
{
rb_tree_t *rt = &f->ooo_deq_lookup;
svm_fifo_chunk_t *c;
rb_node_t *n;
c = start;
while (c && !f_chunk_includes_pos (c, end_pos))
{
if (c->deq_rb_index != RBTREE_TNIL_INDEX)
{
n = rb_node (rt, c->deq_rb_index);
rb_tree_del_node (rt, n);
c->deq_rb_index = RBTREE_TNIL_INDEX;
}
c = c->next;
}
return c;
}
void
svm_fifo_free_chunk_lookup (svm_fifo_t * f)
{
rb_tree_free_nodes (&f->ooo_enq_lookup);
rb_tree_free_nodes (&f->ooo_deq_lookup);
}
void
svm_fifo_free (svm_fifo_t * f)
{
ASSERT (f->refcnt > 0);
if (--f->refcnt == 0)
{
/* ooo data is not allocated on segment heap */
svm_fifo_free_chunk_lookup (f);
clib_mem_free (f);
}
}
void
svm_fifo_overwrite_head (svm_fifo_t * f, u8 * src, u32 len)
{
u32 n_chunk;
u32 head, tail, head_idx;
svm_fifo_chunk_t *c;
ASSERT (len <= f->size);
f_load_head_tail_cons (f, &head, &tail);
if (!f->head_chunk)
f->head_chunk = svm_fifo_find_chunk (f, head);
c = f->head_chunk;
head_idx = head - c->start_byte;
n_chunk = c->length - head_idx;
if (len <= n_chunk)
clib_memcpy_fast (&c->data[head_idx], src, len);
else
{
ASSERT (len - n_chunk <= c->next->length);
clib_memcpy_fast (&c->data[head_idx], src, n_chunk);
clib_memcpy_fast (&c->next->data[0], src + n_chunk, len - n_chunk);
}
}
static int
f_try_chunk_alloc (svm_fifo_t * f, u32 head, u32 tail, u32 len)
{
svm_fifo_chunk_t *c, *cur, *prev;
u32 alloc_size, free_alloced;
free_alloced = f_chunk_end (f->end_chunk) - tail;
alloc_size = clib_min (f->min_alloc, f->size - (tail - head));
alloc_size = clib_max (alloc_size, len - free_alloced);
c = fsh_alloc_chunk (f->fs_hdr, f->slice_index, alloc_size);
if (PREDICT_FALSE (!c))
return -1;
cur = c;
prev = f->end_chunk;
while (cur)
{
cur->start_byte = prev->start_byte + prev->length;
cur->enq_rb_index = RBTREE_TNIL_INDEX;
cur->deq_rb_index = RBTREE_TNIL_INDEX;
prev = cur;
cur = cur->next;
}
prev->next = 0;
f->end_chunk->next = c;
f->end_chunk = prev;
if (!f->tail_chunk)
f->tail_chunk = c;
return 0;
}
int
svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src)
{
u32 tail, head, free_count;
svm_fifo_chunk_t *old_tail_c;
f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
f_load_head_tail_prod (f, &head, &tail);
/* free space in fifo can only increase during enqueue: SPSC */
free_count = f_free_count (f, head, tail);
if (PREDICT_FALSE (free_count == 0))
return SVM_FIFO_EFULL;
/* number of bytes we're going to copy */
len = clib_min (free_count, len);
if (f_pos_gt (tail + len, f_chunk_end (f->end_chunk)))
{
if (PREDICT_FALSE (f_try_chunk_alloc (f, head, tail, len)))
{
len = f_chunk_end (f->end_chunk) - tail;
if (!len)
return SVM_FIFO_EGROW;
}
}
old_tail_c = f->tail_chunk;
svm_fifo_copy_to_chunk (f, f->tail_chunk, tail, src, len, &f->tail_chunk);
tail = tail + len;
svm_fifo_trace_add (f, head, len, 2);
/* collect out-of-order segments */
if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX))
{
len += ooo_segment_try_collect (f, len, &tail);
/* Tail chunk might've changed even if nothing was collected */
f->tail_chunk = f_lookup_clear_enq_chunks (f, old_tail_c, tail);
f->ooo_enq = 0;
}
/* store-rel: producer owned index (paired with load-acq in consumer) */
clib_atomic_store_rel_n (&f->tail, tail);
return len;
}
/**
* Enqueue a future segment.
*
* 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
*/
int
svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src)
{
u32 tail, head, free_count, enq_pos;
f_load_head_tail_prod (f, &head, &tail);
/* free space in fifo can only increase during enqueue: SPSC */
free_count = f_free_count (f, head, tail);
f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
/* will this request fit? */
if ((len + offset) > free_count)
return SVM_FIFO_EFULL;
enq_pos = tail + offset;
if (f_pos_gt (enq_pos + len, f_chunk_end (f->end_chunk)))
{
if (PREDICT_FALSE (f_try_chunk_alloc (f, head, tail, offset + len)))
return SVM_FIFO_EGROW;
}
svm_fifo_trace_add (f, offset, len, 1);
ooo_segment_add (f, offset, head, tail, len);
if (!f->ooo_enq || !f_chunk_includes_pos (f->ooo_enq, enq_pos))
f_update_ooo_enq (f, enq_pos, enq_pos + len);
svm_fifo_copy_to_chunk (f, f->ooo_enq, enq_pos, src, len, &f->ooo_enq);
return 0;
}
/**
* Advance tail
*/
void
svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len)
{
u32 tail;
ASSERT (len <= svm_fifo_max_enqueue_prod (f));
/* load-relaxed: producer owned index */
tail = f->tail;
tail = tail + len;
if (rb_tree_is_init (&f->ooo_enq_lookup))
{
f->tail_chunk = f_lookup_clear_enq_chunks (f, f->tail_chunk, tail);
f->ooo_enq = 0;
}
else
{
f->tail_chunk = svm_fifo_find_next_chunk (f, f->tail_chunk, tail);
}
/* store-rel: producer owned index (paired with load-acq in consumer) */
clib_atomic_store_rel_n (&f->tail, tail);
}
always_inline svm_fifo_chunk_t *
f_unlink_chunks (svm_fifo_t * f, u32 end_pos, u8 maybe_ooo)
{
svm_fifo_chunk_t *start, *prev = 0, *c;
rb_tree_t *rt;
rb_node_t *n;
ASSERT (!f_chunk_includes_pos (f->start_chunk, end_pos));
if (maybe_ooo)
rt = &f->ooo_deq_lookup;
c = f->start_chunk;
do
{
if (maybe_ooo && c->deq_rb_index != RBTREE_TNIL_INDEX)
{
n = rb_node (rt, c->deq_rb_index);
ASSERT (n == f_find_node_rbtree (rt, c->start_byte));
rb_tree_del_node (rt, n);
c->deq_rb_index = RBTREE_TNIL_INDEX;
}
if (!c->next)
break;
prev = c;
c = c->next;
}
while (!f_chunk_includes_pos (c, end_pos));
if (maybe_ooo)
{
if (f->ooo_deq && f_pos_lt (f->ooo_deq->start_byte, f_chunk_end (c)))
f->ooo_deq = 0;
}
else
{
if (PREDICT_FALSE (f->ooo_deq != 0))
f->ooo_deq = 0;
}
/* Avoid unlinking the last chunk */
if (!prev)
return 0;
prev->next = 0;
start = f->start_chunk;
f->start_chunk = c;
return start;
}
int
svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst)
{
u32 tail, head, cursize;
f_load_head_tail_cons (f, &head, &tail);
/* current size of fifo can only increase during dequeue: SPSC */
cursize = f_cursize (f, head, tail);
if (PREDICT_FALSE (cursize == 0))
return SVM_FIFO_EEMPTY;
len = clib_min (cursize, len);
if (!f->head_chunk)
f->head_chunk = svm_fifo_find_chunk (f, head);
svm_fifo_copy_from_chunk (f, f->head_chunk, head, dst, len, &f->head_chunk);
head = head + len;
/* In order dequeues are not supported in combination with ooo peeking.
* Use svm_fifo_dequeue_drop instead. */
ASSERT (rb_tree_n_nodes (&f->ooo_deq_lookup) <= 1);
if (f_pos_geq (head, f_chunk_end (f->start_chunk)))
fsh_collect_chunks (f->fs_hdr, f->slice_index,
f_unlink_chunks (f, head, 0));
/* store-rel: consumer owned index (paired with load-acq in producer) */
clib_atomic_store_rel_n (&f->head, head);
return len;
}
int
svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst)
{
u32 tail, head, cursize, head_idx;
f_load_head_tail_cons (f, &head, &tail);
/* current size of fifo can only increase during peek: SPSC */
cursize = f_cursize (f, head, tail);
if (PREDICT_FALSE (cursize < offset))
return SVM_FIFO_EEMPTY;
len = clib_min (cursize - offset, len);
head_idx = head + offset;
if (!f->ooo_deq || !f_chunk_includes_pos (f->ooo_deq, head_idx))
f_update_ooo_deq (f, head_idx, head_idx + len);
svm_fifo_copy_from_chunk (f, f->ooo_deq, head_idx, dst, len, &f->ooo_deq);
return len;
}
int
svm_fifo_dequeue_drop (svm_fifo_t * f, u32 len)
{
u32 total_drop_bytes, tail, head, cursize;
f_load_head_tail_cons (f, &head, &tail);
/* number of bytes available */
cursize = f_cursize (f, head, tail);
if (PREDICT_FALSE (cursize == 0))
return SVM_FIFO_EEMPTY;
/* number of bytes we're going to drop */
total_drop_bytes = clib_min (cursize, len);
svm_fifo_trace_add (f, tail, total_drop_bytes, 3);
/* move head */
head = head + total_drop_bytes;
if (f_pos_geq (head, f_chunk_end (f->start_chunk)))
{
fsh_collect_chunks (f->fs_hdr, f->slice_index,
f_unlink_chunks (f, head, 1));
f->head_chunk =
f_chunk_includes_pos (f->start_chunk, head) ? f->start_chunk : 0;
}
/* store-rel: consumer owned index (paired with load-acq in producer) */
clib_atomic_store_rel_n (&f->head, head);
return total_drop_bytes;
}
/**
* Drop all data from fifo
*
*/
void
svm_fifo_dequeue_drop_all (svm_fifo_t * f)
{
u32 head, tail;
f_load_head_tail_all_acq (f, &head, &tail);
if (!f->head_chunk || !f_chunk_includes_pos (f->head_chunk, head))
f->head_chunk = svm_fifo_find_chunk (f, head);
f->head_chunk = f_lookup_clear_deq_chunks (f, f->head_chunk, tail);
if (f_pos_geq (tail, f_chunk_end (f->start_chunk)))
fsh_collect_chunks (f->fs_hdr, f->slice_index,
f_unlink_chunks (f, tail, 0));
/* store-rel: consumer owned index (paired with load-acq in producer) */
clib_atomic_store_rel_n (&f->head, tail);
}
int
svm_fifo_fill_chunk_list (svm_fifo_t * f)
{
u32 head, tail;
f_load_head_tail_prod (f, &head, &tail);
if (f_chunk_end (f->end_chunk) - head >= f->size)
return 0;
if (f_try_chunk_alloc (f, head, tail, f->size - (tail - head)))
return SVM_FIFO_EGROW;
return 0;
}
int
svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs)
{
u32 cursize, head, tail, head_idx;
f_load_head_tail_cons (f, &head, &tail);
/* consumer function, cursize can only increase while we're working */
cursize = f_cursize (f, head, tail);
if (PREDICT_FALSE (cursize == 0))
return SVM_FIFO_EEMPTY;
head_idx = head;
if (tail < head)
{
fs[0].len = f->size - head_idx;
fs[0].data = f->head_chunk->data + head_idx;
fs[1].len = cursize - fs[0].len;
fs[1].data = f->head_chunk->data;
}
else
{
fs[0].len = cursize;
fs[0].data = f->head_chunk->data + head_idx;
fs[1].len = 0;
fs[1].data = 0;
}
return cursize;
}
void
svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs)
{
u32 head;
/* consumer owned index */
head = f->head;
ASSERT (fs[0].data == f->head_chunk->data + head);
head = (head + fs[0].len + fs[1].len);
/* store-rel: consumer owned index (paired with load-acq in producer) */
clib_atomic_store_rel_n (&f->head, head);
}
/**
* Clones fifo
*
* Assumptions:
* - no prod and cons are accessing either dest or src fifo
* - fifo is not multi chunk
*/
void
svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf)
{
u32 head, tail;
/* Support only single chunk clones for now */
ASSERT (svm_fifo_n_chunks (sf) == 1);
clib_memcpy_fast (df->head_chunk->data, sf->head_chunk->data, sf->size);
f_load_head_tail_all_acq (sf, &head, &tail);
clib_atomic_store_rel_n (&df->head, head);
clib_atomic_store_rel_n (&df->tail, tail);
}
u32
svm_fifo_n_ooo_segments (svm_fifo_t * f)
{
return pool_elts (f->ooo_segments);
}
ooo_segment_t *
svm_fifo_first_ooo_segment (svm_fifo_t * f)
{
return pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
}
/**
* Set fifo pointers to requested offset
*/
void
svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail)
{
svm_fifo_chunk_t *c;
clib_atomic_store_rel_n (&f->head, head);
clib_atomic_store_rel_n (&f->tail, tail);
c = svm_fifo_find_chunk (f, head);
ASSERT (c != 0);
f->head_chunk = f->ooo_deq = c;
c = svm_fifo_find_chunk (f, tail);
ASSERT (c != 0);
f->tail_chunk = f->ooo_enq = c;
}
void
svm_fifo_add_subscriber (svm_fifo_t * f, u8 subscriber)
{
if (f->n_subscribers >= SVM_FIFO_MAX_EVT_SUBSCRIBERS)
return;
f->subscribers[f->n_subscribers++] = subscriber;
}
void
svm_fifo_del_subscriber (svm_fifo_t * f, u8 subscriber)
{
int i;
for (i = 0; i < f->n_subscribers; i++)
{
if (f->subscribers[i] != subscriber)
continue;
f->subscribers[i] = f->subscribers[f->n_subscribers - 1];
f->n_subscribers--;
break;
}
}
u8
svm_fifo_is_sane (svm_fifo_t * f)
{
svm_fifo_chunk_t *tmp;
if (f->head_chunk && !f_chunk_includes_pos (f->head_chunk, f->head))
return 0;
if (f->tail_chunk && !f_chunk_includes_pos (f->tail_chunk, f->tail))
return 0;
if (f->ooo_deq)
{
if (rb_tree_is_init (&f->ooo_deq_lookup))
{
if (f_pos_lt (f->ooo_deq->start_byte, f->start_chunk->start_byte)
|| f_pos_gt (f->ooo_deq->start_byte,
f_chunk_end (f->end_chunk)))
return 0;
tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup,
f->ooo_deq->start_byte);
}
else
tmp = svm_fifo_find_chunk (f, f->ooo_deq->start_byte);
if (tmp != f->ooo_deq)
return 0;
}
if (f->ooo_enq)
{
if (rb_tree_is_init (&f->ooo_enq_lookup))
{
if (f_pos_lt (f->ooo_enq->start_byte, f->start_chunk->start_byte)
|| f_pos_gt (f->ooo_enq->start_byte,
f_chunk_end (f->end_chunk)))
return 0;
tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup,
f->ooo_enq->start_byte);
}
else
{
tmp = svm_fifo_find_next_chunk (f, f->tail_chunk,
f->ooo_enq->start_byte);
}
if (tmp != f->ooo_enq)
return 0;
}
if (f->start_chunk->next)
{
svm_fifo_chunk_t *c, *prev = 0, *tmp;
u32 chunks_bytes = 0;
c = f->start_chunk;
do
{
tmp = svm_fifo_find_chunk (f, c->start_byte);
if (tmp != c)
return 0;
if (prev && (prev->start_byte + prev->length != c->start_byte))
return 0;
if (c->enq_rb_index != RBTREE_TNIL_INDEX)
{
tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup, c->start_byte);
if (tmp)
{
if (tmp != c)
return 0;
}
}
if (c->deq_rb_index != RBTREE_TNIL_INDEX)
{
tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup, c->start_byte);
if (tmp)
{
if (tmp != c)
return 0;
}
}
chunks_bytes += c->length;
prev = c;
c = c->next;
}
while (c);
if (chunks_bytes < f->tail - f->head)
return 0;
}
return 1;
}
u32
svm_fifo_n_chunks (svm_fifo_t * f)
{
svm_fifo_chunk_t *c;
int n_chunks = 0;
c = f->start_chunk;
while (c)
{
n_chunks++;
c = c->next;
}
return n_chunks;
}
u8 *
format_ooo_segment (u8 * s, va_list * args)
{
svm_fifo_t __clib_unused *f = va_arg (*args, svm_fifo_t *);
ooo_segment_t *seg = va_arg (*args, ooo_segment_t *);
s = format (s, "[%u, %u], len %u, next %d, prev %d", seg->start,
seg->start + seg->length, seg->length, seg->next, seg->prev);
return s;
}
u8 *
svm_fifo_dump_trace (u8 * s, svm_fifo_t * f)
{
#if SVM_FIFO_TRACE
svm_fifo_trace_elem_t *seg = 0;
int i = 0;
if (f->trace)
{
vec_foreach (seg, f->trace)
{
s = format (s, "{%u, %u, %u}, ", seg->offset, seg->len, seg->action);
i++;
if (i % 5 == 0)
s = format (s, "\n");
}
s = format (s, "\n");
}
return s;
#else
return 0;
#endif
}
u8 *
svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose)
{
int i, trace_len;
u8 *data = 0;
svm_fifo_trace_elem_t *trace;
u32 offset;
svm_fifo_t *placeholder_fifo;
if (!f)
return s;
#if SVM_FIFO_TRACE
trace = f->trace;
trace_len = vec_len (trace);
#else
trace = 0;
trace_len = 0;
#endif
placeholder_fifo = svm_fifo_alloc (f->size);
svm_fifo_init (f, f->size);
clib_memset (f->head_chunk->data, 0xFF, f->size);
vec_validate (data, f->size);
for (i = 0; i < vec_len (data); i++)
data[i] = i;
for (i = 0; i < trace_len; i++)
{
offset = trace[i].offset;
if (trace[i].action == 1)
{
if (verbose)
s = format (s, "adding [%u, %u]:", trace[i].offset,
(trace[i].offset + trace[i].len));
svm_fifo_enqueue_with_offset (placeholder_fifo, trace[i].offset,
trace[i].len, &data[offset]);
}
else if (trace[i].action == 2)
{
if (verbose)
s = format (s, "adding [%u, %u]:", 0, trace[i].len);
svm_fifo_enqueue (placeholder_fifo, trace[i].len, &data[offset]);
}
else if (!no_read)
{
if (verbose)
s = format (s, "read: %u", trace[i].len);
svm_fifo_dequeue_drop (placeholder_fifo, trace[i].len);
}
if (verbose)
s = format (s, "%U", format_svm_fifo, placeholder_fifo, 1);
}
s = format (s, "result: %U", format_svm_fifo, placeholder_fifo, 1);
return s;
}
u8 *
format_ooo_list (u8 * s, va_list * args)
{
svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
u32 indent = va_arg (*args, u32);
u32 ooo_segment_index = f->ooos_list_head;
ooo_segment_t *seg;
while (ooo_segment_index != OOO_SEGMENT_INVALID_INDEX)
{
seg = pool_elt_at_index (f->ooo_segments, ooo_segment_index);
s = format (s, "%U%U\n", format_white_space, indent, format_ooo_segment,
f, seg);
ooo_segment_index = seg->next;
}
return s;
}
u8 *
format_svm_fifo (u8 * s, va_list * args)
{
svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
int verbose = va_arg (*args, int);
u32 indent;
if (!s)
return s;
indent = format_get_indent (s);
s = format (s, "cursize %u nitems %u has_event %d min_alloc %u\n",
svm_fifo_max_dequeue (f), f->size, f->has_event, f->min_alloc);
s = format (s, "%Uhead %u tail %u segment manager %u\n", format_white_space,
indent, f->head, f->tail, f->segment_manager);
if (verbose > 1)
s = format (s, "%Uvpp session %d thread %d app session %d thread %d\n",
format_white_space, indent, f->master_session_index,
f->master_thread_index, f->client_session_index,
f->client_thread_index);
if (verbose)
{
s = format (s, "%Uooo pool %d active elts newest %u\n",
format_white_space, indent, pool_elts (f->ooo_segments),
f->ooos_newest);
if (svm_fifo_has_ooo_data (f))
s = format (s, " %U", format_ooo_list, f, indent, verbose);
}
return s;
}
#endif
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/