#include <svm/svm_fifo.h>
-#define offset_lt(_a, _b) ((i32)((_a)-(_b)) < 0)
-#define offset_leq(_a, _b) ((i32)((_a)-(_b)) <= 0)
+static inline u8
+position_lt (svm_fifo_t * f, u32 a, u32 b)
+{
+ return (ooo_segment_distance_to_tail (f, a)
+ < ooo_segment_distance_to_tail (f, b));
+}
+
+static inline u8
+position_leq (svm_fifo_t * f, u32 a, u32 b)
+{
+ return (ooo_segment_distance_to_tail (f, a)
+ <= ooo_segment_distance_to_tail (f, b));
+}
+
+static inline u8
+position_gt (svm_fifo_t * f, u32 a, u32 b)
+{
+ return (ooo_segment_distance_to_tail (f, a)
+ > ooo_segment_distance_to_tail (f, b));
+}
+
+static inline u32
+position_diff (svm_fifo_t * f, u32 posa, u32 posb)
+{
+ return ooo_segment_distance_to_tail (f, posa)
+ - ooo_segment_distance_to_tail (f, posb);
+}
+
+static inline u32
+ooo_segment_end_pos (svm_fifo_t * f, ooo_segment_t * s)
+{
+ return (s->start + s->length) % f->nitems;
+}
u8 *
format_ooo_segment (u8 * s, va_list * args)
s = format (s, "cursize %u nitems %u has_event %d\n",
f->cursize, f->nitems, f->has_event);
- s = format (s, "head %d tail %d\n", f->head, f->tail);
+ s = format (s, " head %d tail %d\n", f->head, f->tail);
if (verbose > 1)
s = format
- (s, "server session %d thread %d client session %d thread %d\n",
+ (s, " server session %d thread %d client session %d thread %d\n",
f->master_session_index, f->master_thread_index,
f->client_session_index, f->client_thread_index);
if (verbose)
{
- s = format (s, "ooo pool %d active elts\n",
+ s = format (s, " ooo pool %d active elts\n",
pool_elts (f->ooo_segments));
- s = format (s, "%U", format_ooo_list, f);
+ if (svm_fifo_has_ooo_data (f))
+ s = format (s, " %U", format_ooo_list, f);
}
return s;
}
ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length)
{
ooo_segment_t *s, *new_s, *prev, *next, *it;
- u32 new_index, end_offset, s_sof, s_eof, s_index;
+ u32 new_index, s_end_pos, s_index;
+ u32 normalized_position, normalized_end_position;
- end_offset = offset + length;
+ normalized_position = (f->tail + offset) % f->nitems;
+ normalized_end_position = (f->tail + offset + length) % f->nitems;
+
+ f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
{
- s = ooo_segment_new (f, offset, length);
+ s = ooo_segment_new (f, normalized_position, 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
- && offset_leq (ooo_segment_offset (f, s), offset))
+ && position_lt (f, s->start, normalized_position))
s = pool_elt_at_index (f->ooo_segments, s->next);
- s_index = s - f->ooo_segments;
- s_sof = ooo_segment_offset (f, s);
- s_eof = ooo_segment_end_offset (f, s);
+ /* If we have a previous and we overlap it, use it as starting point */
prev = ooo_segment_get_prev (f, s);
+ if (prev
+ && position_leq (f, normalized_position, ooo_segment_end_pos (f, prev)))
+ {
+ s = prev;
+ s_end_pos = ooo_segment_end_pos (f, s);
+ goto merge;
+ }
+
+ s_index = s - f->ooo_segments;
+ s_end_pos = ooo_segment_end_pos (f, s);
/* No overlap, add before current segment */
- if (offset_lt (end_offset, s_sof)
- && (!prev || offset_lt (prev->start + prev->length, offset)))
+ if (position_lt (f, normalized_end_position, s->start))
{
- new_s = ooo_segment_new (f, offset, length);
+ new_s = ooo_segment_new (f, normalized_position, length);
new_index = new_s - f->ooo_segments;
/* Pool might've moved, get segment again */
f->ooos_list_head = new_index;
}
- new_s->next = s - f->ooo_segments;
+ new_s->next = s_index;
s->prev = new_index;
f->ooos_newest = new_index;
return;
}
/* No overlap, add after current segment */
- else if (offset_lt (s_eof, offset))
+ else if (position_gt (f, normalized_position, s_end_pos))
{
- new_s = ooo_segment_new (f, offset, length);
+ new_s = ooo_segment_new (f, normalized_position, 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->next != OOO_SEGMENT_INVALID_INDEX)
- {
- new_s->next = s->next;
- next = pool_elt_at_index (f->ooo_segments, new_s->next);
- next->prev = new_index;
- }
+ ASSERT (s->next == OOO_SEGMENT_INVALID_INDEX);
- new_s->prev = s - f->ooo_segments;
+ new_s->prev = s_index;
s->next = new_index;
f->ooos_newest = new_index;
* Merge needed
*/
+merge:
+
/* Merge at head */
- if (offset_leq (offset, s_sof))
+ if (position_lt (f, normalized_position, s->start))
{
- /* If we have a previous, check if we overlap */
- if (s->prev != OOO_SEGMENT_INVALID_INDEX)
- {
- prev = pool_elt_at_index (f->ooo_segments, s->prev);
-
- /* New segment merges prev and current. Remove previous and
- * update position of current. */
- if (offset_leq (offset, ooo_segment_end_offset (f, prev)))
- {
- s->start = prev->start;
- s->length = s_eof - ooo_segment_offset (f, prev);
- ooo_segment_del (f, s->prev);
- }
- else
- {
- s->start = offset;
- s->length = s_eof - ooo_segment_offset (f, s);
- }
- }
- else
- {
- s->start = offset;
- s->length = s_eof - ooo_segment_offset (f, s);
- }
-
- /* The new segment's tail may cover multiple smaller ones */
- if (offset_lt (s_eof, end_offset))
- {
- /* Remove segments completely covered */
- it = (s->next != OOO_SEGMENT_INVALID_INDEX) ?
- pool_elt_at_index (f->ooo_segments, s->next) : 0;
- while (it && offset_lt (ooo_segment_end_offset (f, it), end_offset))
- {
- next = (it->next != OOO_SEGMENT_INVALID_INDEX) ?
- pool_elt_at_index (f->ooo_segments, it->next) : 0;
- ooo_segment_del (f, it - f->ooo_segments);
- it = next;
- }
-
- /* Update length. Segment's start might have changed. */
- s->length = end_offset - ooo_segment_offset (f, s);
-
- /* If partial overlap with last, merge */
- if (it && offset_lt (ooo_segment_offset (f, it), end_offset))
- {
- s->length +=
- it->length - (ooo_segment_offset (f, it) - end_offset);
- ooo_segment_del (f, it - f->ooo_segments);
- }
- }
+ s->start = normalized_position;
+ s->length = position_diff (f, s_end_pos, s->start);
}
- /* Last but overlapping previous */
- else if (offset_leq (s_eof, end_offset))
+ /* Overlapping tail */
+ else if (position_gt (f, normalized_end_position, s_end_pos))
{
- s->length = end_offset - ooo_segment_offset (f, s);
+ s->length = position_diff (f, normalized_end_position, s->start);
}
/* New segment completely covered by current one */
else
{
/* Do Nothing */
+ s = 0;
+ goto done;
+ }
+
+ /* The new segment's tail may cover multiple smaller ones */
+ if (position_gt (f, normalized_end_position, s_end_pos))
+ {
+ /* Remove the completely overlapped segments */
+ it = (s->next != OOO_SEGMENT_INVALID_INDEX) ?
+ pool_elt_at_index (f->ooo_segments, s->next) : 0;
+ while (it && position_leq (f, ooo_segment_end_pos (f, it),
+ normalized_end_position))
+ {
+ next = (it->next != OOO_SEGMENT_INVALID_INDEX) ?
+ pool_elt_at_index (f->ooo_segments, it->next) : 0;
+ ooo_segment_del (f, it - f->ooo_segments);
+ it = next;
+ }
+
+ /* If partial overlap with last, merge */
+ if (it && position_leq (f, it->start, normalized_end_position))
+ {
+ s->length = ooo_segment_end_pos (f, it) - s->start;
+ ooo_segment_del (f, it - f->ooo_segments);
+ }
}
+done:
/* Most recently updated segment */
- f->ooos_newest = s - f->ooo_segments;
+ if (s)
+ f->ooos_newest = s - f->ooo_segments;
}
/**
ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued)
{
ooo_segment_t *s;
- u32 index, bytes = 0, diff;
- u32 cursize;
-
- /* current size has not yet been updated */
- cursize = svm_fifo_max_dequeue (f) + n_bytes_enqueued;
+ u32 index, bytes = 0;
+ i32 diff;
s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
- diff = (f->nitems + (i32) (f->tail - s->start)) % f->nitems;
- if (diff > cursize)
+ diff = (f->tail >= s->start) ?
+ f->tail - s->start : f->nitems + f->tail - s->start;
+
+ if (diff > n_bytes_enqueued)
return 0;
/* If last tail update overlaps one/multiple ooo segments, remove them */
- while (0 < diff && diff < cursize)
+ while (0 <= diff && diff < n_bytes_enqueued)
{
index = s - f->ooo_segments;
/* Segment end is beyond the tail. Advance tail and remove segment */
- if (diff < s->length)
+ if (s->length > diff)
{
- f->tail += s->length - diff;
- f->tail %= f->nitems;
bytes = s->length - diff;
+ f->tail += bytes;
+ f->tail %= f->nitems;
ooo_segment_del (f, index);
break;
}
if (s->next != OOO_SEGMENT_INVALID_INDEX)
{
s = pool_elt_at_index (f->ooo_segments, s->next);
- diff = (f->nitems + (i32) (f->tail - s->start)) % f->nitems;
+ diff = (f->tail >= s->start) ?
+ f->tail - s->start : f->nitems + f->tail - s->start;
ooo_segment_del (f, index);
}
/* End of search */
}
}
- /* If tail is adjacent to an ooo segment, 'consume' it */
- if (diff == 0)
- {
- bytes = ((f->nitems - cursize) >= s->length) ? s->length :
- f->nitems - cursize;
-
- f->tail += bytes;
- f->tail %= f->nitems;
-
- ooo_segment_del (f, s - f->ooo_segments);
- }
-
return bytes;
}
/* 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 -2; /* fifo stuffed */
u8 * copy_from_here)
{
u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
- u32 cursize, nitems;
- u32 normalized_offset;
- int rv;
+ u32 cursize, nitems, normalized_offset;
+ u32 offset_from_tail;
- /* Users would do well to avoid this */
- if (PREDICT_FALSE (f->tail == (offset % f->nitems)))
- {
- rv = svm_fifo_enqueue_internal (f, required_bytes, copy_from_here);
- if (rv > 0)
- return 0;
- return -1;
- }
+ f->ooos_newest = OOO_SEGMENT_INVALID_INDEX;
/* read cursize, which can only increase while we're working */
cursize = svm_fifo_max_dequeue (f);
nitems = f->nitems;
+ normalized_offset = (f->tail + offset) % nitems;
+
/* Will this request fit? */
- if ((required_bytes + (offset - f->tail) % nitems) > (nitems - cursize))
+ offset_from_tail = (nitems + normalized_offset - f->tail) % nitems;
+ if ((required_bytes + offset_from_tail) > (nitems - cursize))
return -1;
ooo_segment_add (f, offset, required_bytes);
/* Number of bytes we're going to copy */
total_copy_bytes = required_bytes;
- normalized_offset = offset % nitems;
/* Number of bytes in first copy segment */
first_copy_bytes = ((nitems - normalized_offset) < total_copy_bytes)
/* read cursize, which can only increase while we're working */
cursize = svm_fifo_max_dequeue (f);
- if (PREDICT_FALSE (cursize == 0))
+ if (PREDICT_FALSE (cursize < relative_offset))
return -2; /* nothing in the fifo */
nitems = f->nitems;
real_head = real_head >= nitems ? real_head - nitems : real_head;
/* Number of bytes we're going to copy */
- total_copy_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+ total_copy_bytes = (cursize - relative_offset < max_bytes) ?
+ cursize - relative_offset : max_bytes;
if (PREDICT_TRUE (copy_here != 0))
{
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 pointer)
+{
+ f->head = f->tail = pointer % f->nitems;
+}
+
/*
* fd.io coding-style-patch-verification: ON
*
Code Review / vpp.git / blobdiff