X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fsvm%2Fsvm_fifo.c;h=da60fee51ec2477bd97b7b5d0dfae5485e2f1ea0;hb=2c25a62cc1cc4937165de740a3b32d78429c72d6;hp=097bab77c9c6322ceebd66f683d1eae2c15c0f32;hpb=6cf30adc2cd3aa818e5d97cf71ea8b2fc2aaefa7;p=vpp.git diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c index 097bab77c9c..da60fee51ec 100644 --- a/src/svm/svm_fifo.c +++ b/src/svm/svm_fifo.c @@ -14,6 +14,93 @@ */ #include +#include + +static inline u8 +position_lt (svm_fifo_t * f, u32 a, u32 b) +{ + return (ooo_segment_distance_from_tail (f, a) + < ooo_segment_distance_from_tail (f, b)); +} + +static inline u8 +position_leq (svm_fifo_t * f, u32 a, u32 b) +{ + return (ooo_segment_distance_from_tail (f, a) + <= ooo_segment_distance_from_tail (f, b)); +} + +static inline u8 +position_gt (svm_fifo_t * f, u32 a, u32 b) +{ + return (ooo_segment_distance_from_tail (f, a) + > ooo_segment_distance_from_tail (f, b)); +} + +static inline u32 +position_diff (svm_fifo_t * f, u32 posa, u32 posb) +{ + return ooo_segment_distance_from_tail (f, posa) + - ooo_segment_distance_from_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) +{ + ooo_segment_t *seg = va_arg (*args, ooo_segment_t *); + + s = format (s, "pos %u, len %u, next %d, prev %d", + seg->start, seg->length, seg->next, seg->prev); + return s; +} + +u8 * +format_ooo_list (u8 * s, va_list * args) +{ + svm_fifo_t *f = va_arg (*args, svm_fifo_t *); + 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\n", format_ooo_segment, 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); + + 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); + + if (verbose > 1) + s = format + (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", + pool_elts (f->ooo_segments)); + if (svm_fifo_has_ooo_data (f)) + s = format (s, " %U", format_ooo_list, f); + } + return s; +} /** create an svm fifo, in the current heap. Fails vs blow up the process */ svm_fifo_t * @@ -26,7 +113,7 @@ svm_fifo_create (u32 data_size_in_bytes) if (f == 0) return 0; - memset (f, 0, sizeof (*f) + data_size_in_bytes); + memset (f, 0, sizeof (*f)); f->nitems = data_size_in_bytes; f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX; @@ -47,7 +134,7 @@ ooo_segment_new (svm_fifo_t * f, u32 start, u32 length) pool_get (f->ooo_segments, s); - s->fifo_position = start; + s->start = start; s->length = length; s->prev = s->next = OOO_SEGMENT_INVALID_INDEX; @@ -88,14 +175,17 @@ static void ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) { ooo_segment_t *s, *new_s, *prev, *next, *it; - u32 new_index, position, end_offset, s_sof, s_eof, s_index; + u32 new_index, s_end_pos, s_index; + u32 normalized_position, normalized_end_position; + + normalized_position = (f->tail + offset) % f->nitems; + normalized_end_position = (f->tail + offset + length) % f->nitems; - position = (f->tail + offset) % f->nitems; - end_offset = offset + length; + f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX) { - s = ooo_segment_new (f, position, 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; @@ -104,26 +194,45 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) /* 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 - && ooo_segment_offset (f, s) <= offset) + && position_lt (f, s->start, normalized_position)) 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); + if (prev + && position_leq (f, normalized_position, ooo_segment_end_pos (f, prev))) + { + s = prev; + s_end_pos = ooo_segment_end_pos (f, s); + + /* Check head and tail now since segment may be wider at both ends so + * merge tests lower won't work */ + if (position_lt (f, normalized_position, s->start)) + { + s->start = normalized_position; + s->length = position_diff (f, s_end_pos, s->start); + } + if (position_gt (f, normalized_end_position, s_end_pos)) + { + s->length = position_diff (f, normalized_end_position, s->start); + } + goto check_tail; + } + s_index = s - f->ooo_segments; - s_sof = ooo_segment_offset (f, s); - s_eof = ooo_segment_end_offset (f, s); + s_end_pos = ooo_segment_end_pos (f, s); /* No overlap, add before current segment */ - if (end_offset < s_sof) + if (position_lt (f, normalized_end_position, s->start)) { - new_s = ooo_segment_new (f, position, 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->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; } @@ -133,29 +242,23 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) 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 (s_eof < offset) + else if (position_gt (f, normalized_position, s_end_pos)) { - new_s = ooo_segment_new (f, position, 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; + ASSERT (s->next == OOO_SEGMENT_INVALID_INDEX); - next = pool_elt_at_index (f->ooo_segments, new_s->next); - next->prev = new_index; - } - - new_s->prev = s - f->ooo_segments; + new_s->prev = s_index; s->next = new_index; f->ooos_newest = new_index; @@ -167,67 +270,53 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) */ /* Merge at head */ - if (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 (ooo_segment_end_offset (f, prev) >= offset) - { - s->fifo_position = prev->fifo_position; - s->length = s_eof - ooo_segment_offset (f, prev); - ooo_segment_del (f, s->prev); - } - } - else - { - s->fifo_position = position; - s->length = s_eof - ooo_segment_offset (f, s); - } - - /* The new segment's tail may cover multiple smaller ones */ - if (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 && 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 && 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 (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; } +check_tail: + /* 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 = + position_diff (f, 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; } /** @@ -238,64 +327,60 @@ static int ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued) { ooo_segment_t *s; - u32 index, bytes = 0, diff; - u32 cursize; - - /* read cursize, which can only increase while we're working */ - cursize = svm_fifo_max_dequeue (f); + 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); + + ASSERT (diff != n_bytes_enqueued); + + if (diff > n_bytes_enqueued) + return 0; /* If last tail update overlaps one/multiple ooo segments, remove them */ - diff = (f->nitems + f->tail - s->fifo_position) % f->nitems; - while (0 < diff && diff < n_bytes_enqueued) + while (0 <= diff && diff < n_bytes_enqueued) { - /* Segment end is beyond the tail. Advance tail and be done */ - if (diff < s->length) + index = s - f->ooo_segments; + + /* Segment end is beyond the tail. Advance tail and remove segment */ + if (s->length > diff) { - f->tail += s->length - diff; + bytes = s->length - diff; + f->tail += bytes; f->tail %= f->nitems; + ooo_segment_del (f, index); break; } + /* If we have next go on */ - else if (s->next != OOO_SEGMENT_INVALID_INDEX) + if (s->next != OOO_SEGMENT_INVALID_INDEX) { - index = s - f->ooo_segments; s = pool_elt_at_index (f->ooo_segments, s->next); - diff = (f->nitems + f->tail - s->fifo_position) % f->nitems; + diff = ooo_segment_distance_to_tail (f, s->start); ooo_segment_del (f, index); } /* End of search */ else { + ooo_segment_del (f, index); break; } } - /* 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); - } - + ASSERT (bytes >= 0 && bytes <= f->nitems); return bytes; } static int -svm_fifo_enqueue_internal (svm_fifo_t * f, - int pid, u32 max_bytes, u8 * copy_from_here) +svm_fifo_enqueue_internal (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here) { 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 -2; /* fifo stuffed */ @@ -328,6 +413,8 @@ svm_fifo_enqueue_internal (svm_fifo_t * f, } else { + ASSERT (0); + /* Account for a zero-copy enqueue done elsewhere */ ASSERT (max_bytes <= (nitems - cursize)); f->tail += max_bytes; @@ -340,16 +427,44 @@ svm_fifo_enqueue_internal (svm_fifo_t * f, total_copy_bytes += ooo_segment_try_collect (f, total_copy_bytes); /* Atomically increase the queue length */ + ASSERT (cursize + total_copy_bytes <= nitems); __sync_fetch_and_add (&f->cursize, total_copy_bytes); return (total_copy_bytes); } +#define SVM_ENQUEUE_CLONE_TEMPLATE(arch, fn, tgt) \ + uword \ + __attribute__ ((flatten)) \ + __attribute__ ((target (tgt))) \ + CLIB_CPU_OPTIMIZED \ + fn ## _ ## arch ( svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here) \ + { return fn (f, max_bytes, copy_from_here);} + +static int +svm_fifo_enqueue_nowait_ma (svm_fifo_t * f, u32 max_bytes, + u8 * copy_from_here) +{ + return svm_fifo_enqueue_internal (f, max_bytes, copy_from_here); +} + +foreach_march_variant (SVM_ENQUEUE_CLONE_TEMPLATE, + svm_fifo_enqueue_nowait_ma); +CLIB_MULTIARCH_SELECT_FN (svm_fifo_enqueue_nowait_ma); + int -svm_fifo_enqueue_nowait (svm_fifo_t * f, - int pid, u32 max_bytes, u8 * copy_from_here) +svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here) { - return svm_fifo_enqueue_internal (f, pid, max_bytes, copy_from_here); +#if CLIB_DEBUG > 0 + return svm_fifo_enqueue_nowait_ma (f, max_bytes, copy_from_here); +#else + static int (*fp) (svm_fifo_t *, u32, u8 *); + + if (PREDICT_FALSE (fp == 0)) + fp = (void *) svm_fifo_enqueue_nowait_ma_multiarch_select (); + + return (*fp) (f, max_bytes, copy_from_here); +#endif } /** @@ -361,47 +476,50 @@ svm_fifo_enqueue_nowait (svm_fifo_t * f, */ static int svm_fifo_enqueue_with_offset_internal (svm_fifo_t * f, - int pid, u32 offset, u32 required_bytes, u8 * copy_from_here) { u32 total_copy_bytes, first_copy_bytes, second_copy_bytes; - u32 cursize, nitems; - u32 tail_plus_offset; + u32 cursize, nitems, normalized_offset; + u32 offset_from_tail; - ASSERT (offset > 0); + 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; + ASSERT (required_bytes < nitems); + + normalized_offset = (f->tail + offset) % nitems; + /* Will this request fit? */ - if ((required_bytes + offset) > (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; - tail_plus_offset = (f->tail + offset) % nitems; /* Number of bytes in first copy segment */ - first_copy_bytes = ((nitems - tail_plus_offset) < total_copy_bytes) - ? (nitems - tail_plus_offset) : total_copy_bytes; + first_copy_bytes = ((nitems - normalized_offset) < total_copy_bytes) + ? (nitems - normalized_offset) : total_copy_bytes; - clib_memcpy (&f->data[tail_plus_offset], copy_from_here, first_copy_bytes); + clib_memcpy (&f->data[normalized_offset], copy_from_here, first_copy_bytes); /* Number of bytes in second copy segment, if any */ second_copy_bytes = total_copy_bytes - first_copy_bytes; if (second_copy_bytes) { - tail_plus_offset += first_copy_bytes; - tail_plus_offset %= nitems; + normalized_offset += first_copy_bytes; + normalized_offset %= nitems; - ASSERT (tail_plus_offset == 0); + ASSERT (normalized_offset == 0); - clib_memcpy (&f->data[tail_plus_offset], + clib_memcpy (&f->data[normalized_offset], copy_from_here + first_copy_bytes, second_copy_bytes); } @@ -411,18 +529,16 @@ svm_fifo_enqueue_with_offset_internal (svm_fifo_t * f, int svm_fifo_enqueue_with_offset (svm_fifo_t * f, - int pid, u32 offset, u32 required_bytes, u8 * copy_from_here) { - return svm_fifo_enqueue_with_offset_internal - (f, pid, offset, required_bytes, copy_from_here); + return svm_fifo_enqueue_with_offset_internal (f, offset, required_bytes, + copy_from_here); } static int -svm_fifo_dequeue_internal (svm_fifo_t * f, - int pid, u32 max_bytes, u8 * copy_here) +svm_fifo_dequeue_internal (svm_fifo_t * f, u32 max_bytes, u8 * copy_here) { u32 total_copy_bytes, first_copy_bytes, second_copy_bytes; u32 cursize, nitems; @@ -458,6 +574,7 @@ svm_fifo_dequeue_internal (svm_fifo_t * f, } else { + ASSERT (0); /* Account for a zero-copy dequeue done elsewhere */ ASSERT (max_bytes <= cursize); f->head += max_bytes; @@ -466,36 +583,66 @@ svm_fifo_dequeue_internal (svm_fifo_t * f, total_copy_bytes = max_bytes; } + ASSERT (f->head <= nitems); + ASSERT (cursize >= total_copy_bytes); __sync_fetch_and_sub (&f->cursize, total_copy_bytes); return (total_copy_bytes); } -int -svm_fifo_dequeue_nowait (svm_fifo_t * f, - int pid, u32 max_bytes, u8 * copy_here) +static int +svm_fifo_dequeue_nowait_ma (svm_fifo_t * f, u32 max_bytes, u8 * copy_here) { - return svm_fifo_dequeue_internal (f, pid, max_bytes, copy_here); + return svm_fifo_dequeue_internal (f, max_bytes, copy_here); } +#define SVM_FIFO_DEQUEUE_CLONE_TEMPLATE(arch, fn, tgt) \ + uword \ + __attribute__ ((flatten)) \ + __attribute__ ((target (tgt))) \ + CLIB_CPU_OPTIMIZED \ + fn ## _ ## arch ( svm_fifo_t * f, u32 max_bytes, \ + u8 * copy_here) \ + { return fn (f, max_bytes, copy_here);} + +foreach_march_variant (SVM_FIFO_DEQUEUE_CLONE_TEMPLATE, + svm_fifo_dequeue_nowait_ma); +CLIB_MULTIARCH_SELECT_FN (svm_fifo_dequeue_nowait_ma); + int -svm_fifo_peek (svm_fifo_t * f, int pid, u32 offset, u32 max_bytes, - u8 * copy_here) +svm_fifo_dequeue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_here) +{ +#if CLIB_DEBUG > 0 + return svm_fifo_dequeue_nowait_ma (f, max_bytes, copy_here); +#else + static int (*fp) (svm_fifo_t *, u32, u8 *); + + if (PREDICT_FALSE (fp == 0)) + fp = (void *) svm_fifo_dequeue_nowait_ma_multiarch_select (); + + return (*fp) (f, max_bytes, copy_here); +#endif +} + +static int +svm_fifo_peek_ma (svm_fifo_t * f, u32 relative_offset, u32 max_bytes, + u8 * copy_here) { u32 total_copy_bytes, first_copy_bytes, second_copy_bytes; u32 cursize, nitems, real_head; /* 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 = f->head + offset; + real_head = f->head + relative_offset; 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)) { @@ -516,8 +663,36 @@ svm_fifo_peek (svm_fifo_t * f, int pid, u32 offset, u32 max_bytes, return total_copy_bytes; } +#define SVM_FIFO_PEEK_CLONE_TEMPLATE(arch, fn, tgt) \ + uword \ + __attribute__ ((flatten)) \ + __attribute__ ((target (tgt))) \ + CLIB_CPU_OPTIMIZED \ + fn ## _ ## arch ( svm_fifo_t * f, u32 relative_offset, u32 max_bytes, \ + u8 * copy_here) \ + { return fn (f, relative_offset, max_bytes, copy_here);} + +foreach_march_variant (SVM_FIFO_PEEK_CLONE_TEMPLATE, svm_fifo_peek_ma); +CLIB_MULTIARCH_SELECT_FN (svm_fifo_peek_ma); + +int +svm_fifo_peek (svm_fifo_t * f, u32 relative_offset, u32 max_bytes, + u8 * copy_here) +{ +#if CLIB_DEBUG > 0 + return svm_fifo_peek_ma (f, relative_offset, max_bytes, copy_here); +#else + static int (*fp) (svm_fifo_t *, u32, u32, u8 *); + + if (PREDICT_FALSE (fp == 0)) + fp = (void *) svm_fifo_peek_ma_multiarch_select (); + + return (*fp) (f, relative_offset, max_bytes, copy_here); +#endif +} + int -svm_fifo_dequeue_drop (svm_fifo_t * f, int pid, u32 max_bytes) +svm_fifo_dequeue_drop (svm_fifo_t * f, u32 max_bytes) { u32 total_drop_bytes, first_drop_bytes, second_drop_bytes; u32 cursize, nitems; @@ -547,46 +722,32 @@ svm_fifo_dequeue_drop (svm_fifo_t * f, int pid, u32 max_bytes) f->head = (f->head == nitems) ? 0 : f->head; } + ASSERT (f->head <= nitems); + ASSERT (cursize >= total_drop_bytes); __sync_fetch_and_sub (&f->cursize, total_drop_bytes); return total_drop_bytes; } -u8 * -format_svm_fifo (u8 * s, va_list * args) +u32 +svm_fifo_number_ooo_segments (svm_fifo_t * f) { - svm_fifo_t *f = va_arg (*args, svm_fifo_t *); - int verbose = va_arg (*args, int); - - 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); - - if (verbose > 1) - s = format - (s, "server session %d thread %d client session %d thread %d\n", - f->server_session_index, f->server_thread_index, - f->client_session_index, f->client_thread_index); - - if (verbose) - { - ooo_segment_t *seg; - u32 seg_index; - - s = - format (s, "ooo pool %d active elts\n", pool_elts (f->ooo_segments)); + return pool_elts (f->ooo_segments); +} - seg_index = f->ooos_list_head; +ooo_segment_t * +svm_fifo_first_ooo_segment (svm_fifo_t * f) +{ + return pool_elt_at_index (f->ooo_segments, f->ooos_list_head); +} - while (seg_index != OOO_SEGMENT_INVALID_INDEX) - { - seg = pool_elt_at_index (f->ooo_segments, seg_index); - s = format (s, " pos %u, len %u next %d\n", - seg->fifo_position, seg->length, seg->next); - seg_index = seg->next; - } - } - return s; +/** + * Set fifo pointers to requested offset + */ +void +svm_fifo_init_pointers (svm_fifo_t * f, u32 pointer) +{ + f->head = f->tail = pointer % f->nitems; } /*