From d68faf8559da72aa6ad0526d5a86fb16587b1508 Mon Sep 17 00:00:00 2001 From: Florin Coras Date: Fri, 25 Sep 2020 15:18:13 -0700 Subject: vcl svm: provide apps access to fifo chunks Type: feature Signed-off-by: Florin Coras Change-Id: I2191b8594b1e87ecc00f237316457db249f73603 --- src/svm/svm_fifo.c | 49 ++++++++++++++++++++----------------------------- 1 file changed, 20 insertions(+), 29 deletions(-) (limited to 'src/svm/svm_fifo.c') diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c index fda9481e721..2cce2bf50b3 100644 --- a/src/svm/svm_fifo.c +++ b/src/svm/svm_fifo.c @@ -1136,9 +1136,11 @@ svm_fifo_fill_chunk_list (svm_fifo_t * f) } int -svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs) +svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs, u32 n_segs, + u32 max_bytes) { - u32 cursize, head, tail, head_idx; + u32 cursize, to_read, head, tail, fs_index = 1, n_bytes, head_pos, len; + svm_fifo_chunk_t *c; f_load_head_tail_cons (f, &head, &tail); @@ -1148,37 +1150,26 @@ svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs) if (PREDICT_FALSE (cursize == 0)) return SVM_FIFO_EEMPTY; - head_idx = head; + to_read = clib_min (cursize, max_bytes); - 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 + c = f->head_chunk; + head_pos = head - c->start_byte; + fs[0].data = c->data + head_pos; + fs[0].len = c->length - head_pos; + n_bytes = fs[0].len; + c = c->next; + + while (n_bytes < to_read && fs_index < n_segs) { - fs[0].len = cursize; - fs[0].data = f->head_chunk->data + head_idx; - fs[1].len = 0; - fs[1].data = 0; + len = clib_min (c->length, to_read - n_bytes); + fs[fs_index].data = c->data; + fs[fs_index].len = len; + n_bytes += len; + c = c->next; + fs_index += 1; } - 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); + return n_bytes; } /** -- cgit 1.2.3-korg