diff options
| -rw-r--r-- | src/plugins/unittest/svm_fifo_test.c | 9 | ||||
| -rw-r--r-- | src/svm/svm_fifo.c | 44 | ||||
| -rw-r--r-- | src/svm/svm_fifo.h | 48 |
3 files changed, 48 insertions, 53 deletions
diff --git a/src/plugins/unittest/svm_fifo_test.c b/src/plugins/unittest/svm_fifo_test.c index 99f0e5044d6..d2afc36e0d0 100644 --- a/src/plugins/unittest/svm_fifo_test.c +++ b/src/plugins/unittest/svm_fifo_test.c @@ -806,7 +806,7 @@ sfifo_test_fifo4 (vlib_main_t * vm, unformat_input_t * input) static u32 fifo_pos (svm_fifo_t * f, u32 pos) { - return pos; + return pos % f->size; } /* Avoids exposing svm_fifo.c internal function */ @@ -1194,6 +1194,7 @@ sfifo_test_fifo_grow (vlib_main_t * vm, unformat_input_t * input) svm_fifo_chunk_t *c, *next, *prev; u8 *test_data = 0, *data_buf = 0; svm_fifo_t *f; + u32 old_tail; while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT) { @@ -1288,10 +1289,14 @@ sfifo_test_fifo_grow (vlib_main_t * vm, unformat_input_t * input) SFIFO_TEST (f->size == fifo_size + 200, "size expected %u is %u", fifo_size + 200, f->size); - svm_fifo_dequeue (f, 201, data_buf); + old_tail = f->tail; + svm_fifo_dequeue (f, 101, data_buf); SFIFO_TEST (f->size == fifo_size + 200 + 10 * 100, "size expected %u is %u", fifo_size + 200 + 10 * 100, f->size); + SFIFO_TEST (f->tail == old_tail, "new tail expected %u is %u", old_tail, + f->tail); + /* * Enqueue/dequeue tests */ diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c index 3512c72d9f1..d5638777290 100644 --- a/src/svm/svm_fifo.c +++ b/src/svm/svm_fifo.c @@ -125,7 +125,7 @@ position_diff (svm_fifo_t * f, u32 a, u32 b, u32 tail) static inline u32 ooo_segment_end_pos (svm_fifo_t * f, ooo_segment_t * s) { - return s->start + s->length; + return (s->start + s->length) % f->size; } void @@ -202,8 +202,8 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 head, u32 tail, u32 length) ASSERT (offset + length <= f_distance_to (f, head, tail) || head == tail); - offset_pos = tail + offset; - offset_end_pos = tail + offset + length; + offset_pos = (tail + offset) % f->size; + offset_end_pos = (tail + offset + length) % f->size; f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; @@ -350,7 +350,7 @@ ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail) if (s->length > diff) { bytes = s->length - diff; - *tail = *tail + bytes; + *tail = (*tail + bytes) % f->size; ooo_segment_free (f, s_index); break; } @@ -460,7 +460,7 @@ svm_fifo_size_update (svm_fifo_t * f, svm_fifo_chunk_t * c) static void svm_fifo_try_size_update (svm_fifo_t * f, u32 new_head) { - if (new_head % f->size > f->tail % f->size) + if (new_head > f->tail) return; svm_fifo_size_update (f, f->new_chunks); @@ -603,8 +603,7 @@ svm_fifo_overwrite_head (svm_fifo_t * f, u8 * src, u32 len) f_load_head_tail_cons (f, &head, &tail); c = f->head_chunk; - head_idx = head % f->size; - head_idx -= c->start_byte; + 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); @@ -632,9 +631,8 @@ svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src) /* number of bytes we're going to copy */ len = clib_min (free_count, len); - svm_fifo_copy_to_chunk (f, f->tail_chunk, tail % f->size, src, len, - &f->tail_chunk); - tail += 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); @@ -672,7 +670,7 @@ svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src) 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 % f->size + offset) % f->size; + 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); @@ -696,9 +694,8 @@ svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst) return SVM_FIFO_EEMPTY; len = clib_min (cursize, len); - svm_fifo_copy_from_chunk (f, f->head_chunk, head % f->size, dst, len, - &f->head_chunk); - head += 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_SIZE_UPDATE)) svm_fifo_try_size_update (f, head); @@ -723,7 +720,7 @@ svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst) return SVM_FIFO_EEMPTY; len = clib_min (cursize - offset, len); - head_idx = (head % f->size + offset) % f->size; + 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); @@ -749,7 +746,7 @@ svm_fifo_dequeue_drop (svm_fifo_t * f, u32 len) total_drop_bytes = clib_min (cursize, len); /* move head */ - head += total_drop_bytes; + head = (head + total_drop_bytes) % f->size; /* store-rel: consumer owned index (paired with load-acq in producer) */ clib_atomic_store_rel_n (&f->head, head); @@ -779,7 +776,7 @@ svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs) if (PREDICT_FALSE (cursize == 0)) return SVM_FIFO_EEMPTY; - head_idx = head % f->size; + head_idx = head; if (tail < head) { @@ -801,14 +798,13 @@ svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs) void svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs) { - u32 head, head_idx; + u32 head; /* consumer owned index */ head = f->head; - head_idx = head % f->size; - ASSERT (fs[0].data == f->head_chunk->data + head_idx); - head += fs[0].len + fs[1].len; + 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); } @@ -849,15 +845,17 @@ svm_fifo_first_ooo_segment (svm_fifo_t * f) void svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail) { + 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 % f->size); + c = svm_fifo_find_chunk (f, head); ASSERT (c != 0); f->head_chunk = f->ooo_deq = c; - c = svm_fifo_find_chunk (f, tail % f->size); + c = svm_fifo_find_chunk (f, tail); ASSERT (c != 0); f->tail_chunk = f->ooo_enq = c; } diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h index 96ca3ee01c6..390e1170e27 100644 --- a/src/svm/svm_fifo.h +++ b/src/svm/svm_fifo.h @@ -186,47 +186,47 @@ f_load_head_tail_all_acq (svm_fifo_t * f, u32 * head, u32 * tail) } /** - * Fifo free bytes, i.e., number of free bytes + * Distance to a from b, i.e., a - b in the fifo * - * Internal function + * Internal function. */ static inline u32 -f_free_count (svm_fifo_t * f, u32 head, u32 tail) +f_distance_to (svm_fifo_t * f, u32 a, u32 b) { - return (f->nitems + head - tail); + return ((f->size + a - b) % f->size); } /** - * Fifo current size, i.e., number of bytes enqueued + * Distance from a to b, i.e., b - a in the fifo * * Internal function. */ static inline u32 -f_cursize (svm_fifo_t * f, u32 head, u32 tail) +f_distance_from (svm_fifo_t * f, u32 a, u32 b) { - return (f->nitems - f_free_count (f, head, tail)); + return ((f->size + b - a) % f->size); } /** - * Distance to a from b, i.e., a - b in the fifo + * Fifo current size, i.e., number of bytes enqueued * * Internal function. */ static inline u32 -f_distance_to (svm_fifo_t * f, u32 a, u32 b) +f_cursize (svm_fifo_t * f, u32 head, u32 tail) { - return ((f->size + a - b) % f->size); + return (head <= tail ? tail - head : f->size + tail - head); } /** - * Distance from a to b, i.e., b - a in the fifo + * Fifo free bytes, i.e., number of free bytes * - * Internal function. + * Internal function */ static inline u32 -f_distance_from (svm_fifo_t * f, u32 a, u32 b) +f_free_count (svm_fifo_t * f, u32 head, u32 tail) { - return ((f->size + b - a) % f->size); + return (f->nitems - f_cursize (f, head, tail)); } /** @@ -535,7 +535,7 @@ svm_fifo_is_wrapped (svm_fifo_t * f) { u32 head, tail; f_load_head_tail_all_acq (f, &head, &tail); - return head % f->size > tail % f->size; + return head > tail; } /** @@ -575,11 +575,8 @@ static inline u32 svm_fifo_max_read_chunk (svm_fifo_t * f) { u32 head, tail; - u32 head_idx, tail_idx; f_load_head_tail_cons (f, &head, &tail); - head_idx = head % f->size; - tail_idx = tail % f->size; - return tail_idx > head_idx ? (tail_idx - head_idx) : (f->size - head_idx); + return tail >= head ? (tail - head) : (f->size - head); } /** @@ -589,11 +586,8 @@ static inline u32 svm_fifo_max_write_chunk (svm_fifo_t * f) { u32 head, tail; - u32 head_idx, tail_idx; f_load_head_tail_prod (f, &head, &tail); - head_idx = head % f->size; - tail_idx = tail % f->size; - return tail_idx >= head_idx ? (f->size - tail_idx) : (head_idx - tail_idx); + return tail > head ? f->size - tail : f_free_count (f, head, tail); } /** @@ -610,7 +604,7 @@ svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len) ASSERT (len <= svm_fifo_max_enqueue_prod (f)); /* load-relaxed: producer owned index */ u32 tail = f->tail; - tail += len; + tail = (tail + len) % f->size; /* store-rel: producer owned index (paired with load-acq in consumer) */ clib_atomic_store_rel_n (&f->tail, tail); } @@ -619,16 +613,14 @@ static inline u8 * svm_fifo_head (svm_fifo_t * f) { /* load-relaxed: consumer owned index */ - return (f->head_chunk->data - + ((f->head % f->size) - f->head_chunk->start_byte)); + return (f->head_chunk->data + (f->head - f->head_chunk->start_byte)); } static inline u8 * svm_fifo_tail (svm_fifo_t * f) { /* load-relaxed: producer owned index */ - return (f->tail_chunk->data - + ((f->tail % f->size) - f->tail_chunk->start_byte)); + return (f->tail_chunk->data + (f->tail - f->tail_chunk->start_byte)); } static inline u8 |