diff options
Diffstat (limited to 'src/svm')
| -rw-r--r-- | src/svm/svm_fifo.c | 144 | ||||
| -rw-r--r-- | src/svm/svm_fifo.h | 1 |
2 files changed, 70 insertions, 75 deletions
diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c index 8f2ed0c9..9b09d0c2 100644 --- a/src/svm/svm_fifo.c +++ b/src/svm/svm_fifo.c @@ -17,6 +17,8 @@ #define offset_lt(_a, _b) ((i32)((_a)-(_b)) < 0) #define offset_leq(_a, _b) ((i32)((_a)-(_b)) <= 0) +#define offset_gt(_a, _b) ((i32)((_a)-(_b)) > 0) +#define offset_geq(_a, _b) ((i32)((_a)-(_b)) >= 0) u8 * format_ooo_segment (u8 * s, va_list * args) @@ -160,14 +162,23 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) && offset_leq (ooo_segment_offset (f, s), offset)) 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 && offset_leq (offset, ooo_segment_end_offset (f, prev))) + { + s = prev; + prev = ooo_segment_get_prev (f, s); + s_sof = ooo_segment_offset (f, s); + s_eof = ooo_segment_end_offset (f, s); + goto merge; + } + s_index = s - f->ooo_segments; s_sof = ooo_segment_offset (f, s); s_eof = ooo_segment_end_offset (f, s); - prev = ooo_segment_get_prev (f, s); /* No overlap, add before current segment */ - if (offset_lt (end_offset, s_sof) - && (!prev || offset_lt (prev->start + prev->length, offset))) + if (offset_lt (end_offset, s_sof)) { new_s = ooo_segment_new (f, offset, length); new_index = new_s - f->ooo_segments; @@ -192,7 +203,7 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) return; } /* No overlap, add after current segment */ - else if (offset_lt (s_eof, offset)) + else if (offset_gt (offset, s_eof)) { new_s = ooo_segment_new (f, offset, length); new_index = new_s - f->ooo_segments; @@ -218,62 +229,16 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) * Merge needed */ +merge: + /* Merge at head */ - if (offset_leq (offset, s_sof)) + if (offset_lt (offset, s_sof)) { - /* 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 = offset; + s->length = s_eof - ooo_segment_offset (f, s); } /* Last but overlapping previous */ - else if (offset_leq (s_eof, end_offset)) + else if (offset_gt (end_offset, s_eof)) { s->length = end_offset - ooo_segment_offset (f, s); } @@ -281,8 +246,33 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) else { /* Do Nothing */ + goto done; + } + + /* The new segment's tail may cover multiple smaller ones */ + if (offset_geq (end_offset, s_eof)) + { + /* Remove the completely overlapped segments */ + it = (s->next != OOO_SEGMENT_INVALID_INDEX) ? + pool_elt_at_index (f->ooo_segments, s->next) : 0; + while (it && offset_leq (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; + } + + /* If partial overlap with last, merge */ + if (it && offset_leq (ooo_segment_offset (f, it), end_offset)) + { + s->length = ooo_segment_end_offset (f, it) - + ooo_segment_offset (f, s); + ooo_segment_del (f, it - f->ooo_segments); + } } +done: /* Most recently updated segment */ f->ooos_newest = s - f->ooo_segments; } @@ -296,14 +286,17 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued) { ooo_segment_t *s; u32 index, bytes = 0, diff; - u32 cursize; + u32 cursize, norm_start, nitems; /* current size has not yet been updated */ cursize = svm_fifo_max_dequeue (f) + n_bytes_enqueued; + nitems = f->nitems; s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head); - diff = (f->nitems + (i32) (f->tail - s->start)) % f->nitems; + norm_start = s->start % nitems; + diff = (f->nitems + (i32) (f->tail - norm_start)) % nitems; + if (diff > cursize) return 0; @@ -326,7 +319,8 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued) 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; + norm_start = s->start % nitems; + diff = (f->nitems + (i32) (f->tail - norm_start)) % nitems; ooo_segment_del (f, index); } /* End of search */ @@ -340,11 +334,11 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued) /* If tail is adjacent to an ooo segment, 'consume' it */ if (diff == 0) { - bytes = ((f->nitems - cursize) >= s->length) ? s->length : - f->nitems - cursize; + bytes = ((nitems - cursize) >= s->length) ? s->length : + nitems - cursize; f->tail += bytes; - f->tail %= f->nitems; + f->tail %= nitems; ooo_segment_del (f, s - f->ooo_segments); } @@ -430,31 +424,22 @@ svm_fifo_enqueue_with_offset_internal (svm_fifo_t * f, { u32 total_copy_bytes, first_copy_bytes, second_copy_bytes; u32 cursize, nitems; - u32 normalized_offset; - int rv; - - /* 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; - } + u32 normalized_offset, offset_from_tail; /* read cursize, which can only increase while we're working */ cursize = svm_fifo_max_dequeue (f); nitems = f->nitems; + normalized_offset = 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) @@ -631,6 +616,15 @@ 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 pointer) +{ + f->head = f->tail = pointer % f->nitems; +} + /* * fd.io coding-style-patch-verification: ON * diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h index d67237c6..36158dc5 100644 --- a/src/svm/svm_fifo.h +++ b/src/svm/svm_fifo.h @@ -119,6 +119,7 @@ int svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 max_bytes, u8 * copy_here); int svm_fifo_dequeue_drop (svm_fifo_t * f, u32 max_bytes); u32 svm_fifo_number_ooo_segments (svm_fifo_t * f); ooo_segment_t *svm_fifo_first_ooo_segment (svm_fifo_t * f); +void svm_fifo_init_pointers (svm_fifo_t * f, u32 pointer); format_function_t format_svm_fifo; |