/*
- * Copyright (c) 2016 Cisco and/or its affiliates.
+ * 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:
#include <svm/svm_fifo.h>
#include <vppinfra/cpu.h>
-static inline u8
-position_lt (svm_fifo_t * f, u32 a, u32 b)
+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)
{
- return (ooo_segment_distance_from_tail (f, a)
- < ooo_segment_distance_from_tail (f, b));
+ u32 n_chunk;
+
+ ASSERT (tail_idx >= c->start_byte && 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);
+ }
}
-static inline u8
-position_leq (svm_fifo_t * f, u32 a, u32 b)
+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)
{
- return (ooo_segment_distance_from_tail (f, a)
- <= ooo_segment_distance_from_tail (f, b));
+ u32 n_chunk;
+
+ ASSERT (head_idx >= c->start_byte && 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);
+ }
}
-static inline u8
-position_gt (svm_fifo_t * f, u32 a, u32 b)
+#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)
{
- return (ooo_segment_distance_from_tail (f, a)
- > ooo_segment_distance_from_tail (f, b));
+ CLIB_MARCH_FN_SELECT (svm_fifo_copy_to_chunk) (f, c, tail_idx, src, len,
+ last);
}
-static inline u32
-position_diff (svm_fifo_t * f, u32 posa, u32 posb)
+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)
{
- return ooo_segment_distance_from_tail (f, posa)
- - ooo_segment_distance_from_tail (f, posb);
+ CLIB_MARCH_FN_SELECT (svm_fifo_copy_from_chunk) (f, c, head_idx, dst, len,
+ last);
}
-static inline u32
-ooo_segment_end_pos (svm_fifo_t * f, ooo_segment_t * s)
+static inline u8
+position_lt (svm_fifo_t * f, u32 a, u32 b, u32 tail)
{
- return (s->start + s->length) % f->nitems;
+ return (f_distance_to (f, a, tail) < f_distance_to (f, b, tail));
}
-#ifndef CLIB_MARCH_VARIANT
-
-u8 *
-format_ooo_segment (u8 * s, va_list * args)
+static inline u8
+position_leq (svm_fifo_t * f, u32 a, u32 b, u32 tail)
{
- svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
- ooo_segment_t *seg = va_arg (*args, ooo_segment_t *);
- u32 normalized_start = (seg->start + f->nitems - f->tail) % f->nitems;
- s = format (s, "[%u, %u], len %u, next %d, prev %d", normalized_start,
- (normalized_start + seg->length) % f->nitems, seg->length,
- seg->next, seg->prev);
- return s;
+ return (f_distance_to (f, a, tail) <= f_distance_to (f, b, tail));
}
-u8 *
-svm_fifo_dump_trace (u8 * s, svm_fifo_t * f)
+static inline u8
+position_gt (svm_fifo_t * f, u32 a, u32 b, u32 tail)
{
-#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
+ return (f_distance_to (f, a, tail) > f_distance_to (f, b, tail));
}
-u8 *
-svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose)
+static inline u32
+position_diff (svm_fifo_t * f, u32 a, u32 b, u32 tail)
{
- int i, trace_len;
- u8 *data = 0;
- svm_fifo_trace_elem_t *trace;
- u32 offset;
- svm_fifo_t *dummy_fifo;
-
- if (!f)
- return s;
-
-#if SVM_FIFO_TRACE
- trace = f->trace;
- trace_len = vec_len (trace);
-#else
- trace = 0;
- trace_len = 0;
-#endif
-
- dummy_fifo = svm_fifo_create (f->nitems);
- clib_memset (f->data, 0xFF, f->nitems);
-
- vec_validate (data, f->nitems);
- 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) % dummy_fifo->nitems);
- svm_fifo_enqueue_with_offset (dummy_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_nowait (dummy_fifo, trace[i].len, &data[offset]);
- }
- else if (!no_read)
- {
- if (verbose)
- s = format (s, "read: %u", trace[i].len);
- svm_fifo_dequeue_drop (dummy_fifo, trace[i].len);
- }
- if (verbose)
- s = format (s, "%U", format_svm_fifo, dummy_fifo, 1);
- }
-
- s = format (s, "result: %U", format_svm_fifo, dummy_fifo, 1);
-
- return s;
+ return f_distance_to (f, a, tail) - f_distance_to (f, b, tail);
}
-u8 *
-format_ooo_list (u8 * s, va_list * args)
+static inline u32
+ooo_segment_end_pos (svm_fifo_t * f, ooo_segment_t * s)
{
- 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;
+ return (s->start + s->length) % f->size;
}
-u8 *
-format_svm_fifo (u8 * s, va_list * args)
+void
+svm_fifo_free_ooo_data (svm_fifo_t * f)
{
- 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\n",
- f->cursize, f->nitems, f->has_event);
- s = format (s, "%Uhead %d tail %d 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;
+ pool_free (f->ooo_segments);
}
-/** create an svm fifo, in the current heap. Fails vs blow up the process */
-svm_fifo_t *
-svm_fifo_create (u32 data_size_in_bytes)
+static inline ooo_segment_t *
+ooo_segment_prev (svm_fifo_t * f, ooo_segment_t * s)
{
- svm_fifo_t *f;
- u32 rounded_data_size;
-
- /* always round fifo data size to the next highest power-of-two */
- rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
- f = clib_mem_alloc_aligned_or_null (sizeof (*f) + rounded_data_size,
- CLIB_CACHE_LINE_BYTES);
- if (f == 0)
+ if (s->prev == OOO_SEGMENT_INVALID_INDEX)
return 0;
-
- clib_memset (f, 0, sizeof (*f));
- f->nitems = data_size_in_bytes;
- f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
- f->ct_session_index = SVM_FIFO_INVALID_SESSION_INDEX;
- f->refcnt = 1;
- return (f);
+ return pool_elt_at_index (f->ooo_segments, s->prev);
}
-void
-svm_fifo_free (svm_fifo_t * f)
+static inline ooo_segment_t *
+ooo_segment_next (svm_fifo_t * f, ooo_segment_t * s)
{
- ASSERT (f->refcnt > 0);
-
- if (--f->refcnt == 0)
- {
- pool_free (f->ooo_segments);
- clib_mem_free (f);
- }
+ if (s->next == OOO_SEGMENT_INVALID_INDEX)
+ return 0;
+ return pool_elt_at_index (f->ooo_segments, s->next);
}
-#endif
-always_inline ooo_segment_t *
-ooo_segment_new (svm_fifo_t * f, u32 start, u32 length)
+static inline ooo_segment_t *
+ooo_segment_alloc (svm_fifo_t * f, u32 start, u32 length)
{
ooo_segment_t *s;
s->start = start;
s->length = length;
-
s->prev = s->next = OOO_SEGMENT_INVALID_INDEX;
return s;
}
-always_inline void
-ooo_segment_del (svm_fifo_t * f, u32 index)
+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);
* adjacent segments and removing overlapping ones.
*/
static void
-ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length)
+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 normalized_position, normalized_end_position;
+ u32 offset_pos, offset_end_pos;
+
+ ASSERT (offset + length <= f_distance_to (f, head, tail) || head == tail);
- ASSERT (offset + length <= ooo_segment_distance_from_tail (f, f->head));
- normalized_position = (f->tail + offset) % f->nitems;
- normalized_end_position = (f->tail + offset + length) % f->nitems;
+ offset_pos = (tail + offset) % f->size;
+ offset_end_pos = (tail + offset + length) % f->size;
f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
{
- s = ooo_segment_new (f, normalized_position, length);
+ 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
- && position_lt (f, s->start, normalized_position))
+ && position_lt (f, s->start, offset_pos, tail))
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_get_prev (f, s);
+ prev = ooo_segment_prev (f, s);
if (prev
- && position_leq (f, normalized_position, ooo_segment_end_pos (f, prev)))
+ && position_leq (f, offset_pos, ooo_segment_end_pos (f, prev), tail))
{
s = prev;
s_end_pos = ooo_segment_end_pos (f, s);
- /* Since we have previous, normalized start position cannot be smaller
+ /* Since we have previous, offset start position cannot be smaller
* than prev->start. Check tail */
- ASSERT (position_lt (f, s->start, normalized_position));
+ ASSERT (position_lt (f, s->start, offset_pos, tail));
goto check_tail;
}
s_end_pos = ooo_segment_end_pos (f, s);
/* No overlap, add before current segment */
- if (position_lt (f, normalized_end_position, s->start))
+ if (position_lt (f, offset_end_pos, s->start, tail))
{
- new_s = ooo_segment_new (f, normalized_position, length);
+ new_s = ooo_segment_alloc (f, offset_pos, length);
new_index = new_s - f->ooo_segments;
/* Pool might've moved, get segment again */
return;
}
/* No overlap, add after current segment */
- else if (position_gt (f, normalized_position, s_end_pos))
+ else if (position_gt (f, offset_pos, s_end_pos, tail))
{
- new_s = ooo_segment_new (f, normalized_position, length);
+ new_s = ooo_segment_alloc (f, offset_pos, length);
new_index = new_s - f->ooo_segments;
/* Pool might've moved, get segment again */
*/
/* Merge at head */
- if (position_lt (f, normalized_position, s->start))
+ if (position_lt (f, offset_pos, s->start, tail))
{
- s->start = normalized_position;
- s->length = position_diff (f, s_end_pos, s->start);
+ s->start = offset_pos;
+ s->length = position_diff (f, s_end_pos, s->start, tail);
f->ooos_newest = s - f->ooo_segments;
}
check_tail:
/* Overlapping tail */
- if (position_gt (f, normalized_end_position, s_end_pos))
+ if (position_gt (f, offset_end_pos, s_end_pos, tail))
{
- s->length = position_diff (f, normalized_end_position, s->start);
+ s->length = position_diff (f, offset_end_pos, s->start, tail);
/* Remove the completely overlapped segments in the tail */
it = ooo_segment_next (f, s);
while (it && position_leq (f, ooo_segment_end_pos (f, it),
- normalized_end_position))
+ offset_end_pos, tail))
{
next = ooo_segment_next (f, it);
- ooo_segment_del (f, it - f->ooo_segments);
+ ooo_segment_free (f, it - f->ooo_segments);
it = next;
}
/* If partial overlap with last, merge */
- if (it && position_leq (f, it->start, normalized_end_position))
+ if (it && position_leq (f, it->start, offset_end_pos, tail))
{
s->length = position_diff (f, ooo_segment_end_pos (f, it),
- s->start);
- ooo_segment_del (f, it - f->ooo_segments);
+ s->start, tail);
+ ooo_segment_free (f, it - f->ooo_segments);
}
f->ooos_newest = s - f->ooo_segments;
}
* advanced. Returns the number of bytes added to tail.
*/
static int
-ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued)
+ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail)
{
+ u32 s_index, bytes = 0;
ooo_segment_t *s;
- u32 index, bytes = 0;
i32 diff;
s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
- diff = ooo_segment_distance_to_tail (f, s->start);
+ diff = f_distance_from (f, s->start, *tail);
ASSERT (diff != n_bytes_enqueued);
/* If last tail update overlaps one/multiple ooo segments, remove them */
while (0 <= diff && diff < n_bytes_enqueued)
{
- index = s - f->ooo_segments;
+ 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;
- f->tail += bytes;
- f->tail %= f->nitems;
- ooo_segment_del (f, index);
+ *tail = (*tail + bytes) % f->size;
+ ooo_segment_free (f, s_index);
break;
}
if (s->next != OOO_SEGMENT_INVALID_INDEX)
{
s = pool_elt_at_index (f->ooo_segments, s->next);
- diff = ooo_segment_distance_to_tail (f, s->start);
- ooo_segment_del (f, index);
+ diff = f_distance_from (f, s->start, *tail);
+ ooo_segment_free (f, s_index);
}
/* End of search */
else
{
- ooo_segment_del (f, index);
+ ooo_segment_free (f, s_index);
break;
}
}
return bytes;
}
-CLIB_MARCH_FN (svm_fifo_enqueue_nowait, int, svm_fifo_t * f, u32 max_bytes,
- const u8 * copy_from_here)
+static ooo_segment_t *
+ooo_segment_last (svm_fifo_t * f)
{
- u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
- u32 cursize, nitems;
-
- /* read cursize, which can only increase while we're working */
- cursize = svm_fifo_max_dequeue (f);
- f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
-
- if (PREDICT_FALSE (cursize == f->nitems))
- return SVM_FIFO_FULL;
-
- nitems = f->nitems;
+ ooo_segment_t *s;
- /* Number of bytes we're going to copy */
- total_copy_bytes = (nitems - cursize) < max_bytes ?
- (nitems - cursize) : max_bytes;
+ if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
+ return 0;
- if (PREDICT_TRUE (copy_from_here != 0))
- {
- /* Number of bytes in first copy segment */
- first_copy_bytes = ((nitems - f->tail) < total_copy_bytes)
- ? (nitems - f->tail) : total_copy_bytes;
+ 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;
+}
- clib_memcpy_fast (&f->data[f->tail], copy_from_here, first_copy_bytes);
- f->tail += first_copy_bytes;
- f->tail = (f->tail == nitems) ? 0 : f->tail;
+void
+svm_fifo_init (svm_fifo_t * f, u32 size)
+{
+ f->size = size;
+ /*
+ * usable size of the fifo set to rounded_data_size - 1
+ * to differentiate between free fifo and empty fifo.
+ */
+ f->nitems = f->size - 1;
+ f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
+ f->segment_index = SVM_FIFO_INVALID_INDEX;
+ f->refcnt = 1;
+ f->default_chunk.start_byte = 0;
+ f->default_chunk.length = f->size;
+ f->default_chunk.next = f->start_chunk = f->end_chunk = &f->default_chunk;
+ f->head_chunk = f->tail_chunk = f->ooo_enq = f->ooo_deq = f->start_chunk;
+}
- /* Number of bytes in second copy segment, if any */
- second_copy_bytes = total_copy_bytes - first_copy_bytes;
- if (second_copy_bytes)
- {
- clib_memcpy_fast (&f->data[f->tail],
- copy_from_here + first_copy_bytes,
- second_copy_bytes);
- f->tail += second_copy_bytes;
- f->tail = (f->tail == nitems) ? 0 : f->tail;
- }
- }
- else
- {
- ASSERT (0);
+/**
+ * Creates a fifo in the current heap. Fails vs blow up the process
+ */
+svm_fifo_t *
+svm_fifo_create (u32 data_size_in_bytes)
+{
+ svm_fifo_t *f;
+ u32 rounded_data_size;
- /* Account for a zero-copy enqueue done elsewhere */
- ASSERT (max_bytes <= (nitems - cursize));
- f->tail += max_bytes;
- f->tail = f->tail % nitems;
- total_copy_bytes = max_bytes;
- }
+ /* always round fifo data size to the next highest power-of-two */
+ rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
+ f = clib_mem_alloc_aligned_or_null (sizeof (*f) + rounded_data_size,
+ CLIB_CACHE_LINE_BYTES);
+ if (f == 0)
+ return 0;
- svm_fifo_trace_add (f, f->head, total_copy_bytes, 2);
+ clib_memset (f, 0, sizeof (*f));
+ svm_fifo_init (f, data_size_in_bytes);
+ return f;
+}
- /* Any out-of-order segments to collect? */
- if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX))
- total_copy_bytes += ooo_segment_try_collect (f, total_copy_bytes);
+/**
+ * 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;
- /* Atomically increase the queue length */
- ASSERT (cursize + total_copy_bytes <= nitems);
- clib_atomic_fetch_add (&f->cursize, total_copy_bytes);
+ /* 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;
- return (total_copy_bytes);
+ clib_memset (c, 0, sizeof (*c));
+ c->length = rounded_size;
+ return c;
}
-#ifndef CLIB_MARCH_VARIANT
-int
-svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes,
- const u8 * copy_from_here)
+static inline u8
+svm_fifo_chunk_includes_pos (svm_fifo_chunk_t * c, u32 pos)
{
- return CLIB_MARCH_FN_SELECT (svm_fifo_enqueue_nowait) (f, max_bytes,
- copy_from_here);
+ return (pos >= c->start_byte && pos < c->start_byte + c->length);
}
-#endif
/**
- * Enqueue a future segment.
+ * Find chunk for given byte position
*
- * 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
+ * @param f fifo
+ * @param pos normalized position in fifo
+ *
+ * @return chunk that includes given position or 0
*/
-CLIB_MARCH_FN (svm_fifo_enqueue_with_offset, int, svm_fifo_t * f,
- u32 offset, u32 required_bytes, u8 * copy_from_here)
+static svm_fifo_chunk_t *
+svm_fifo_find_chunk (svm_fifo_t * f, u32 pos)
{
- u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
- u32 cursize, nitems, normalized_offset;
-
- f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
+ rb_tree_t *rt = &f->chunk_lookup;
+ rb_node_t *cur, *prev;
+ svm_fifo_chunk_t *c;
- /* read cursize, which can only increase while we're working */
- cursize = svm_fifo_max_dequeue (f);
- nitems = f->nitems;
+ cur = rb_node (rt, rt->root);
+ while (pos != cur->key)
+ {
+ prev = cur;
+ if (pos < cur->key)
+ cur = rb_node_left (rt, cur);
+ else
+ cur = rb_node_right (rt, cur);
- ASSERT (required_bytes < nitems);
+ if (rb_node_is_tnil (rt, cur))
+ {
+ /* Hit tnil as a left child. Find predecessor */
+ if (pos < prev->key)
+ {
+ cur = rb_tree_predecessor (rt, prev);
+ c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
+ if (svm_fifo_chunk_includes_pos (c, pos))
+ return c;
+ return 0;
+ }
+ /* Hit tnil as a right child. Check if this is the one */
+ c = uword_to_pointer (prev->opaque, svm_fifo_chunk_t *);
+ if (svm_fifo_chunk_includes_pos (c, pos))
+ return c;
+
+ return 0;
+ }
+ }
- normalized_offset = (f->tail + offset) % nitems;
+ if (!rb_node_is_tnil (rt, cur))
+ return uword_to_pointer (cur->opaque, svm_fifo_chunk_t *);
+ return 0;
+}
- /* Will this request fit? */
- if ((required_bytes + offset) > (nitems - cursize))
- return -1;
+static inline void
+svm_fifo_grow (svm_fifo_t * f, svm_fifo_chunk_t * c)
+{
+ svm_fifo_chunk_t *prev;
+ u32 add_bytes = 0;
- svm_fifo_trace_add (f, offset, required_bytes, 1);
+ if (!c)
+ return;
- ooo_segment_add (f, offset, required_bytes);
+ f->end_chunk->next = c;
+ while (c)
+ {
+ add_bytes += c->length;
+ prev = c;
+ c = c->next;
+ }
+ f->end_chunk = prev;
+ prev->next = f->start_chunk;
+ f->size += add_bytes;
+ f->nitems = f->size - 1;
+ f->new_chunks = 0;
+}
- /* Number of bytes we're going to copy */
- total_copy_bytes = required_bytes;
+static void
+svm_fifo_try_grow (svm_fifo_t * f, u32 new_head)
+{
+ if (new_head > f->tail)
+ return;
- /* Number of bytes in first copy segment */
- first_copy_bytes = ((nitems - normalized_offset) < total_copy_bytes)
- ? (nitems - normalized_offset) : total_copy_bytes;
+ svm_fifo_grow (f, f->new_chunks);
+ f->flags &= ~SVM_FIFO_F_GROW;
+}
- clib_memcpy_fast (&f->data[normalized_offset], copy_from_here,
- first_copy_bytes);
+void
+svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c)
+{
+ svm_fifo_chunk_t *cur, *prev;
- /* Number of bytes in second copy segment, if any */
- second_copy_bytes = total_copy_bytes - first_copy_bytes;
- if (second_copy_bytes)
+ /* Initialize rbtree if needed and add default chunk to it. Expectation is
+ * that this is called with the heap where the rbtree's pool is pushed. */
+ if (!(f->flags & SVM_FIFO_F_MULTI_CHUNK))
{
- normalized_offset += first_copy_bytes;
- normalized_offset %= nitems;
+ rb_tree_init (&f->chunk_lookup);
+ rb_tree_add2 (&f->chunk_lookup, 0, pointer_to_uword (f->start_chunk));
+ f->flags |= SVM_FIFO_F_MULTI_CHUNK;
+ }
- ASSERT (normalized_offset == 0);
+ /* Initialize chunks and add to lookup rbtree */
+ cur = c;
+ if (f->new_chunks)
+ {
+ prev = f->new_chunks;
+ while (prev->next)
+ prev = prev->next;
+ prev->next = c;
+ }
+ else
+ prev = f->end_chunk;
- clib_memcpy_fast (&f->data[normalized_offset],
- copy_from_here + first_copy_bytes, second_copy_bytes);
+ while (cur)
+ {
+ cur->start_byte = prev->start_byte + prev->length;
+ rb_tree_add2 (&f->chunk_lookup, cur->start_byte,
+ pointer_to_uword (cur));
+ prev = cur;
+ cur = cur->next;
}
- return (0);
-}
+ /* If fifo is not wrapped, update the size now */
+ if (!svm_fifo_is_wrapped (f))
+ {
+ ASSERT (!f->new_chunks);
+ svm_fifo_grow (f, c);
+ return;
+ }
-#ifndef CLIB_MARCH_VARIANT
+ /* Postpone size update */
+ if (!f->new_chunks)
+ {
+ f->new_chunks = c;
+ f->flags |= SVM_FIFO_F_GROW;
+ }
+}
-int
-svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 required_bytes,
- u8 * copy_from_here)
+/**
+ * Removes chunks that are after fifo end byte
+ */
+svm_fifo_chunk_t *
+svm_fifo_collect_chunks (svm_fifo_t * f)
{
- return CLIB_MARCH_FN_SELECT (svm_fifo_enqueue_with_offset) (f, offset,
- required_bytes,
- copy_from_here);
+ svm_fifo_chunk_t *list, *cur;
+
+ f->flags &= ~SVM_FIFO_F_COLLECT_CHUNKS;
+
+ list = f->new_chunks;
+ f->new_chunks = 0;
+ cur = list;
+ while (cur)
+ {
+ rb_tree_del (&f->chunk_lookup, cur->start_byte);
+ cur = cur->next;
+ }
+
+ return list;
}
void
-svm_fifo_overwrite_head (svm_fifo_t * f, u8 * data, u32 len)
+svm_fifo_try_shrink (svm_fifo_t * f, u32 head, u32 tail)
{
- u32 first_chunk;
- first_chunk = f->nitems - f->head;
- ASSERT (len <= f->nitems);
- if (len <= first_chunk)
- clib_memcpy_fast (&f->data[f->head], data, len);
- else
+ u32 len_to_shrink = 0, tail_pos, len;
+ svm_fifo_chunk_t *cur, *prev, *next, *start;
+
+ tail_pos = tail;
+ if (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX)
+ {
+ ooo_segment_t *last = ooo_segment_last (f);
+ tail_pos = ooo_segment_end_pos (f, last);
+ }
+
+ if (f->size_decrement)
+ {
+ /* Figure out available free space considering that there may be
+ * ooo segments */
+ len = clib_min (f->size_decrement, f_free_count (f, head, tail_pos));
+ f->nitems -= len;
+ f->size_decrement -= len;
+ }
+
+ /* Remove tail chunks if the following hold:
+ * - not wrapped
+ * - last used byte less than start of last chunk
+ */
+ if (tail_pos >= head && tail_pos <= f->end_chunk->start_byte)
+ {
+ /* Lookup the last position not to be removed. Since size still needs
+ * to be nitems + 1, nitems must fall within the usable space */
+ tail_pos = tail_pos > 0 ? tail_pos - 1 : tail_pos;
+ prev = svm_fifo_find_chunk (f, clib_max (f->nitems, tail_pos));
+ next = prev->next;
+ while (next != f->start_chunk)
+ {
+ cur = next;
+ next = cur->next;
+ len_to_shrink += cur->length;
+ }
+ if (len_to_shrink)
+ {
+ f->size -= len_to_shrink;
+ start = prev->next;
+ prev->next = f->start_chunk;
+ f->end_chunk = prev;
+ cur->next = f->new_chunks;
+ f->new_chunks = start;
+ }
+ }
+
+ if (!f->size_decrement && f->size == f->nitems + 1)
{
- clib_memcpy_fast (&f->data[f->head], data, first_chunk);
- clib_memcpy_fast (&f->data[0], data + first_chunk, len - first_chunk);
+ f->flags &= ~SVM_FIFO_F_SHRINK;
+ f->flags |= SVM_FIFO_F_COLLECT_CHUNKS;
+ if (f->start_chunk == f->start_chunk->next)
+ f->flags &= ~SVM_FIFO_F_MULTI_CHUNK;
}
}
-#endif
-CLIB_MARCH_FN (svm_fifo_dequeue_nowait, int, svm_fifo_t * f, u32 max_bytes,
- u8 * copy_here)
+/**
+ * Request to reduce fifo size by amount of bytes
+ */
+int
+svm_fifo_reduce_size (svm_fifo_t * f, u32 len, u8 try_shrink)
{
- u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
- u32 cursize, nitems;
-
- /* read cursize, which can only increase while we're working */
- cursize = svm_fifo_max_dequeue (f);
- if (PREDICT_FALSE (cursize == 0))
- return -2; /* nothing in the fifo */
+ svm_fifo_chunk_t *cur;
+ u32 actual_len = 0;
- nitems = f->nitems;
+ /* Abort if trying to reduce by more than fifo size or if
+ * fifo is undergoing resizing already */
+ if (len >= f->size || f->size > f->nitems + 1
+ || (f->flags & SVM_FIFO_F_SHRINK) || (f->flags & SVM_FIFO_F_GROW))
+ return 0;
- /* Number of bytes we're going to copy */
- total_copy_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+ /* last chunk that will not be removed */
+ cur = svm_fifo_find_chunk (f, f->nitems - len);
- if (PREDICT_TRUE (copy_here != 0))
+ /* sum length of chunks that will be removed */
+ cur = cur->next;
+ while (cur != f->start_chunk)
{
- /* Number of bytes in first copy segment */
- first_copy_bytes = ((nitems - f->head) < total_copy_bytes)
- ? (nitems - f->head) : total_copy_bytes;
- clib_memcpy_fast (copy_here, &f->data[f->head], first_copy_bytes);
- f->head += first_copy_bytes;
- f->head = (f->head == nitems) ? 0 : f->head;
-
- /* Number of bytes in second copy segment, if any */
- second_copy_bytes = total_copy_bytes - first_copy_bytes;
- if (second_copy_bytes)
- {
- clib_memcpy_fast (copy_here + first_copy_bytes,
- &f->data[f->head], second_copy_bytes);
- f->head += second_copy_bytes;
- f->head = (f->head == nitems) ? 0 : f->head;
- }
+ actual_len += cur->length;
+ cur = cur->next;
}
- else
+
+ ASSERT (actual_len <= len);
+ if (!actual_len)
+ return 0;
+
+ f->size_decrement = actual_len;
+ f->flags |= SVM_FIFO_F_SHRINK;
+
+ if (try_shrink)
{
- ASSERT (0);
- /* Account for a zero-copy dequeue done elsewhere */
- ASSERT (max_bytes <= cursize);
- f->head += max_bytes;
- f->head = f->head % nitems;
- cursize -= max_bytes;
- total_copy_bytes = max_bytes;
+ u32 head, tail;
+ f_load_head_tail_prod (f, &head, &tail);
+ svm_fifo_try_shrink (f, head, tail);
}
- ASSERT (f->head <= nitems);
- ASSERT (cursize >= total_copy_bytes);
- clib_atomic_fetch_sub (&f->cursize, total_copy_bytes);
+ return actual_len;
+}
- return (total_copy_bytes);
+void
+svm_fifo_free_chunk_lookup (svm_fifo_t * f)
+{
+ rb_tree_free_nodes (&f->chunk_lookup);
}
-#ifndef CLIB_MARCH_VARIANT
+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->nitems);
+
+ f_load_head_tail_cons (f, &head, &tail);
+ 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
+ {
+ clib_memcpy_fast (&c->data[head_idx], src, n_chunk);
+ clib_memcpy_fast (&c->next->data[0], src + n_chunk, len - n_chunk);
+ }
+}
int
-svm_fifo_dequeue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_here)
+svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src)
{
- return CLIB_MARCH_FN_SELECT (svm_fifo_dequeue_nowait) (f, max_bytes,
- copy_here);
+ u32 tail, head, free_count;
+
+ 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;
+
+ if (PREDICT_FALSE (free_count == 0))
+ return SVM_FIFO_EFULL;
+
+ /* number of bytes we're going to copy */
+ len = clib_min (free_count, len);
+ svm_fifo_copy_to_chunk (f, f->tail_chunk, tail, src, len, &f->tail_chunk);
+ tail = (tail + len) % f->size;
+
+ 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);
+
+ /* store-rel: producer owned index (paired with load-acq in consumer) */
+ clib_atomic_store_rel_n (&f->tail, tail);
+
+ return len;
}
-#endif
-CLIB_MARCH_FN (svm_fifo_peek, int, svm_fifo_t * f, u32 relative_offset,
- u32 max_bytes, u8 * copy_here)
+/**
+ * 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 total_copy_bytes, first_copy_bytes, second_copy_bytes;
- u32 cursize, nitems, real_head;
+ u32 tail, head, free_count, tail_idx;
- /* read cursize, which can only increase while we're working */
- cursize = svm_fifo_max_dequeue (f);
- if (PREDICT_FALSE (cursize < relative_offset))
- return -2; /* nothing in the fifo */
+ f_load_head_tail_prod (f, &head, &tail);
- nitems = f->nitems;
- real_head = f->head + relative_offset;
- real_head = real_head >= nitems ? real_head - nitems : real_head;
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SHRINK))
+ svm_fifo_try_shrink (f, head, tail);
- /* Number of bytes we're going to copy */
- total_copy_bytes = (cursize - relative_offset < max_bytes) ?
- cursize - relative_offset : max_bytes;
+ /* free space in fifo can only increase during enqueue: SPSC */
+ free_count = f_free_count (f, head, tail);
- if (PREDICT_TRUE (copy_here != 0))
- {
- /* Number of bytes in first copy segment */
- first_copy_bytes =
- ((nitems - real_head) < total_copy_bytes) ?
- (nitems - real_head) : total_copy_bytes;
- clib_memcpy_fast (copy_here, &f->data[real_head], first_copy_bytes);
+ /* will this request fit? */
+ if ((len + offset) > free_count)
+ return SVM_FIFO_EFULL;
- /* Number of bytes in second copy segment, if any */
- second_copy_bytes = total_copy_bytes - first_copy_bytes;
- if (second_copy_bytes)
- {
- clib_memcpy_fast (copy_here + first_copy_bytes, &f->data[0],
- second_copy_bytes);
- }
- }
- return total_copy_bytes;
+ f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
+ svm_fifo_trace_add (f, offset, len, 1);
+ ooo_segment_add (f, offset, head, tail, len);
+ tail_idx = (tail + offset) % f->size;
+
+ if (!svm_fifo_chunk_includes_pos (f->ooo_enq, tail_idx))
+ f->ooo_enq = svm_fifo_find_chunk (f, tail_idx);
+
+ svm_fifo_copy_to_chunk (f, f->ooo_enq, tail_idx, src, len, &f->ooo_enq);
+
+ return 0;
}
-#ifndef CLIB_MARCH_VARIANT
+/**
+ * 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) % f->size;
+ /* store-rel: producer owned index (paired with load-acq in consumer) */
+ clib_atomic_store_rel_n (&f->tail, tail);
+}
int
-svm_fifo_peek (svm_fifo_t * f, u32 relative_offset, u32 max_bytes,
- u8 * copy_here)
+svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst)
{
- return CLIB_MARCH_FN_SELECT (svm_fifo_peek) (f, relative_offset, max_bytes,
- copy_here);
+ 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);
+ svm_fifo_copy_from_chunk (f, f->head_chunk, head, dst, len, &f->head_chunk);
+ head = (head + len) % f->size;
+
+ if (PREDICT_FALSE (f->flags & SVM_FIFO_F_GROW))
+ svm_fifo_try_grow (f, head);
+
+ /* store-rel: consumer owned index (paired with load-acq in producer) */
+ clib_atomic_store_rel_n (&f->head, head);
+
+ return len;
}
int
-svm_fifo_dequeue_drop (svm_fifo_t * f, u32 max_bytes)
+svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst)
{
- u32 total_drop_bytes, first_drop_bytes, second_drop_bytes;
- u32 cursize, nitems;
+ u32 tail, head, cursize, head_idx;
- /* read cursize, which can only increase while we're working */
- cursize = svm_fifo_max_dequeue (f);
- if (PREDICT_FALSE (cursize == 0))
- return -2; /* nothing in the fifo */
+ f_load_head_tail_cons (f, &head, &tail);
- nitems = f->nitems;
+ /* current size of fifo can only increase during peek: SPSC */
+ cursize = f_cursize (f, head, tail);
- /* Number of bytes we're going to drop */
- total_drop_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+ if (PREDICT_FALSE (cursize < offset))
+ return SVM_FIFO_EEMPTY;
- svm_fifo_trace_add (f, f->tail, total_drop_bytes, 3);
+ len = clib_min (cursize - offset, len);
+ head_idx = (head + offset) % f->size;
+ if (!svm_fifo_chunk_includes_pos (f->ooo_deq, head_idx))
+ f->ooo_deq = svm_fifo_find_chunk (f, head_idx);
- /* Number of bytes in first copy segment */
- first_drop_bytes =
- ((nitems - f->head) < total_drop_bytes) ?
- (nitems - f->head) : total_drop_bytes;
- f->head += first_drop_bytes;
- f->head = (f->head == nitems) ? 0 : f->head;
+ svm_fifo_copy_from_chunk (f, f->ooo_deq, head_idx, dst, len, &f->ooo_deq);
+ return len;
+}
- /* Number of bytes in second drop segment, if any */
- second_drop_bytes = total_drop_bytes - first_drop_bytes;
- if (second_drop_bytes)
- {
- f->head += second_drop_bytes;
- f->head = (f->head == nitems) ? 0 : f->head;
- }
+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;
+
+ svm_fifo_trace_add (f, tail, total_drop_bytes, 3);
+
+ /* number of bytes we're going to drop */
+ total_drop_bytes = clib_min (cursize, len);
+
+ /* move head */
+ head = (head + total_drop_bytes) % f->size;
- ASSERT (f->head <= nitems);
- ASSERT (cursize >= total_drop_bytes);
- clib_atomic_fetch_sub (&f->cursize, total_drop_bytes);
+ /* store-rel: consumer owned index (paired with load-acq in producer) */
+ clib_atomic_store_rel_n (&f->head, head);
return total_drop_bytes;
}
void
svm_fifo_dequeue_drop_all (svm_fifo_t * f)
{
- f->head = f->tail;
- clib_atomic_fetch_sub (&f->cursize, f->cursize);
+ /* consumer foreign index */
+ u32 tail = clib_atomic_load_acq_n (&f->tail);
+ /* store-rel: consumer owned index (paired with load-acq in producer) */
+ clib_atomic_store_rel_n (&f->head, tail);
}
int
-svm_fifo_segments (svm_fifo_t * f, svm_fifo_segment_t * fs)
+svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs)
{
- u32 cursize, nitems;
+ u32 cursize, head, tail, head_idx;
- /* read cursize, which can only increase while we're working */
- cursize = svm_fifo_max_dequeue (f);
- if (PREDICT_FALSE (cursize == 0))
- return -2;
+ f_load_head_tail_cons (f, &head, &tail);
+
+ /* consumer function, cursize can only increase while we're working */
+ cursize = f_cursize (f, head, tail);
- nitems = f->nitems;
+ if (PREDICT_FALSE (cursize == 0))
+ return SVM_FIFO_EEMPTY;
- fs[0].len = ((nitems - f->head) < cursize) ? (nitems - f->head) : cursize;
- fs[0].data = f->data + f->head;
+ head_idx = head;
- if (fs[0].len < cursize)
+ 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->data;
+ 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;
}
}
void
-svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_segment_t * fs)
+svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs)
{
- u32 total_drop_bytes;
+ u32 head;
- ASSERT (fs[0].data == f->data + f->head);
- if (fs[1].len)
- {
- f->head = fs[1].len;
- total_drop_bytes = fs[0].len + fs[1].len;
- }
- else
- {
- f->head = (f->head + fs[0].len) % f->nitems;
- total_drop_bytes = fs[0].len;
- }
- clib_atomic_fetch_sub (&f->cursize, total_drop_bytes);
+ /* consumer owned index */
+ head = f->head;
+
+ ASSERT (fs[0].data == f->head_chunk->data + head);
+ head = (head + fs[0].len + fs[1].len) % f->size;
+ /* 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;
+ 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_number_ooo_segments (svm_fifo_t * f)
+svm_fifo_n_ooo_segments (svm_fifo_t * f)
{
return pool_elts (f->ooo_segments);
}
* Set fifo pointers to requested offset
*/
void
-svm_fifo_init_pointers (svm_fifo_t * f, u32 pointer)
+svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail)
{
- f->head = f->tail = pointer % f->nitems;
+ head = head % f->size;
+ tail = tail % f->size;
+ clib_atomic_store_rel_n (&f->head, head);
+ clib_atomic_store_rel_n (&f->tail, tail);
+ if (f->flags & SVM_FIFO_F_MULTI_CHUNK)
+ {
+ svm_fifo_chunk_t *c;
+ 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 *
+format_ooo_segment (u8 * s, va_list * args)
+{
+ svm_fifo_t *f = va_arg (*args, svm_fifo_t *);
+ ooo_segment_t *seg = va_arg (*args, ooo_segment_t *);
+ u32 normalized_start = (seg->start + f->nitems - f->tail) % f->size;
+ s = format (s, "[%u, %u], len %u, next %d, prev %d", normalized_start,
+ (normalized_start + seg->length) % f->size, 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 *dummy_fifo;
+
+ if (!f)
+ return s;
+
+#if SVM_FIFO_TRACE
+ trace = f->trace;
+ trace_len = vec_len (trace);
+#else
+ trace = 0;
+ trace_len = 0;
+#endif
+
+ dummy_fifo = svm_fifo_create (f->size);
+ clib_memset (f->head_chunk->data, 0xFF, f->nitems);
+ vec_validate (data, f->nitems);
+ 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) % dummy_fifo->size);
+ svm_fifo_enqueue_with_offset (dummy_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 (dummy_fifo, trace[i].len, &data[offset]);
+ }
+ else if (!no_read)
+ {
+ if (verbose)
+ s = format (s, "read: %u", trace[i].len);
+ svm_fifo_dequeue_drop (dummy_fifo, trace[i].len);
+ }
+ if (verbose)
+ s = format (s, "%U", format_svm_fifo, dummy_fifo, 1);
+ }
+
+ s = format (s, "result: %U", format_svm_fifo, dummy_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\n",
+ svm_fifo_max_dequeue (f), f->nitems, f->has_event);
+ s = format (s, "%Uhead %u tail %u segment manager %u\n", format_white_space,
+ indent, (f->head % f->size), (f->tail % f->size),
+ 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