/* * Copyright (c) 2016-2019 Cisco and/or its affiliates. * Copyright (c) 2019 Arm Limited * Copyright (c) 2010-2017 Intel Corporation and/or its affiliates. * Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org * Inspired from DPDK rte_ring.h (SPSC only) (derived from freebsd bufring.h). * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <svm/svm_fifo.h> #include <svm/fifo_segment.h> #include <vppinfra/cpu.h> CLIB_MARCH_FN (svm_fifo_copy_to_chunk, void, svm_fifo_t * f, svm_fifo_chunk_t * c, u32 tail_idx, const u8 * src, u32 len, svm_fifo_chunk_t ** last) { u32 n_chunk; ASSERT (f_pos_geq (tail_idx, c->start_byte) && f_pos_lt (tail_idx, c->start_byte + c->length)); tail_idx -= c->start_byte; n_chunk = c->length - tail_idx; if (n_chunk <= len) { u32 to_copy = len; clib_memcpy_fast (&c->data[tail_idx], src, n_chunk); c = c->next; while ((to_copy -= n_chunk)) { n_chunk = clib_min (c->length, to_copy); clib_memcpy_fast (&c->data[0], src + (len - to_copy), n_chunk); c = c->length <= to_copy ? c->next : c; } if (*last) *last = c; } else { clib_memcpy_fast (&c->data[tail_idx], src, len); } } CLIB_MARCH_FN (svm_fifo_copy_from_chunk, void, svm_fifo_t * f, svm_fifo_chunk_t * c, u32 head_idx, u8 * dst, u32 len, svm_fifo_chunk_t ** last) { u32 n_chunk; ASSERT (f_pos_geq (head_idx, c->start_byte) && f_pos_lt (head_idx, c->start_byte + c->length)); head_idx -= c->start_byte; n_chunk = c->length - head_idx; if (n_chunk <= len) { u32 to_copy = len; clib_memcpy_fast (dst, &c->data[head_idx], n_chunk); c = c->next; while ((to_copy -= n_chunk)) { n_chunk = clib_min (c->length, to_copy); clib_memcpy_fast (dst + (len - to_copy), &c->data[0], n_chunk); c = c->length <= to_copy ? c->next : c; } if (*last) *last = c; } else { clib_memcpy_fast (dst, &c->data[head_idx], len); } } #ifndef CLIB_MARCH_VARIANT static inline void svm_fifo_copy_to_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c, u32 tail_idx, const u8 * src, u32 len, svm_fifo_chunk_t ** last) { CLIB_MARCH_FN_SELECT (svm_fifo_copy_to_chunk) (f, c, tail_idx, src, len, last); } static inline void svm_fifo_copy_from_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c, u32 head_idx, u8 * dst, u32 len, svm_fifo_chunk_t ** last) { CLIB_MARCH_FN_SELECT (svm_fifo_copy_from_chunk) (f, c, head_idx, dst, len, last); } static inline u32 ooo_segment_end_pos (ooo_segment_t * s) { return (s->start + s->length); } void svm_fifo_free_ooo_data (svm_fifo_t * f) { pool_free (f->ooo_segments); } static inline ooo_segment_t * ooo_segment_prev (svm_fifo_t * f, ooo_segment_t * s) { if (s->prev == OOO_SEGMENT_INVALID_INDEX) return 0; return pool_elt_at_index (f->ooo_segments, s->prev); } static inline ooo_segment_t * ooo_segment_next (svm_fifo_t * f, ooo_segment_t * s) { if (s->next == OOO_SEGMENT_INVALID_INDEX) return 0; return pool_elt_at_index (f->ooo_segments, s->next); } static inline ooo_segment_t * ooo_segment_alloc (svm_fifo_t * f, u32 start, u32 length) { ooo_segment_t *s; pool_get (f->ooo_segments, s); s->start = start; s->length = length; s->prev = s->next = OOO_SEGMENT_INVALID_INDEX; return s; } static inline void ooo_segment_free (svm_fifo_t * f, u32 index) { ooo_segment_t *cur, *prev = 0, *next = 0; cur = pool_elt_at_index (f->ooo_segments, index); if (cur->next != OOO_SEGMENT_INVALID_INDEX) { next = pool_elt_at_index (f->ooo_segments, cur->next); next->prev = cur->prev; } if (cur->prev != OOO_SEGMENT_INVALID_INDEX) { prev = pool_elt_at_index (f->ooo_segments, cur->prev); prev->next = cur->next; } else { f->ooos_list_head = cur->next; } pool_put (f->ooo_segments, cur); } /** * Add segment to fifo's out-of-order segment list. Takes care of merging * adjacent segments and removing overlapping ones. */ static void ooo_segment_add (svm_fifo_t * f, u32 offset, u32 head, u32 tail, u32 length) { ooo_segment_t *s, *new_s, *prev, *next, *it; u32 new_index, s_end_pos, s_index; u32 offset_pos, offset_end_pos; ASSERT (offset + length <= f_free_count (f, head, tail)); offset_pos = tail + offset; offset_end_pos = tail + offset + length; f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX) { s = ooo_segment_alloc (f, offset_pos, 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 && f_pos_lt (s->start, offset_pos)) 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_prev (f, s); if (prev && f_pos_leq (offset_pos, ooo_segment_end_pos (prev))) { s = prev; s_end_pos = ooo_segment_end_pos (s); /* Since we have previous, offset start position cannot be smaller * than prev->start. Check tail */ ASSERT (f_pos_lt (s->start, offset_pos)); goto check_tail; } s_index = s - f->ooo_segments; s_end_pos = ooo_segment_end_pos (s); /* No overlap, add before current segment */ if (f_pos_lt (offset_end_pos, s->start)) { new_s = ooo_segment_alloc (f, offset_pos, 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; } else { /* New head */ f->ooos_list_head = new_index; } new_s->next = s_index; s->prev = new_index; f->ooos_newest = new_index; return; } /* No overlap, add after current segment */ else if (f_pos_gt (offset_pos, s_end_pos)) { new_s = ooo_segment_alloc (f, offset_pos, 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); /* Needs to be last */ ASSERT (s->next == OOO_SEGMENT_INVALID_INDEX); new_s->prev = s_index; s->next = new_index; f->ooos_newest = new_index; return; } /* * Merge needed */ /* Merge at head */ if (f_pos_lt (offset_pos, s->start)) { s->start = offset_pos; s->length = s_end_pos - s->start; f->ooos_newest = s - f->ooo_segments; } check_tail: /* Overlapping tail */ if (f_pos_gt (offset_end_pos, s_end_pos)) { s->length = offset_end_pos - s->start; /* Remove the completely overlapped segments in the tail */ it = ooo_segment_next (f, s); while (it && f_pos_leq (ooo_segment_end_pos (it), offset_end_pos)) { next = ooo_segment_next (f, it); ooo_segment_free (f, it - f->ooo_segments); it = next; } /* If partial overlap with last, merge */ if (it && f_pos_leq (it->start, offset_end_pos)) { s->length = ooo_segment_end_pos (it) - s->start; ooo_segment_free (f, it - f->ooo_segments); } f->ooos_newest = s - f->ooo_segments; } } /** * Removes segments that can now be enqueued because the fifo's tail has * advanced. Returns the number of bytes added to tail. */ static int ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail) { u32 s_index, bytes = 0; ooo_segment_t *s; i32 diff; s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head); diff = *tail - 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 */ while (0 <= diff && diff < n_bytes_enqueued) { s_index = s - f->ooo_segments; /* Segment end is beyond the tail. Advance tail and remove segment */ if (s->length > diff) { bytes = s->length - diff; *tail = *tail + bytes; ooo_segment_free (f, s_index); break; } /* If we have next go on */ if (s->next != OOO_SEGMENT_INVALID_INDEX) { s = pool_elt_at_index (f->ooo_segments, s->next); diff = *tail - s->start; ooo_segment_free (f, s_index); } /* End of search */ else { ooo_segment_free (f, s_index); break; } } ASSERT (bytes <= f->size); return bytes; } __clib_unused static ooo_segment_t * ooo_segment_last (svm_fifo_t * f) { ooo_segment_t *s; if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX) return 0; s = svm_fifo_first_ooo_segment (f); while (s->next != OOO_SEGMENT_INVALID_INDEX) s = pool_elt_at_index (f->ooo_segments, s->next); return s; } void svm_fifo_init (svm_fifo_t * f, u32 size) { svm_fifo_chunk_t *c, *prev; u32 min_alloc; f->size = size; f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX; f->segment_index = SVM_FIFO_INVALID_INDEX; f->refcnt = 1; f->head = f->tail = f->flags = 0; f->head_chunk = f->tail_chunk = f->start_chunk; f->ooo_deq = f->ooo_enq = 0; min_alloc = size > 32 << 10 ? size >> 3 : 4096; min_alloc = clib_min (min_alloc, 64 << 10); f->min_alloc = min_alloc; /* * Initialize chunks */ f->start_chunk->start_byte = 0; prev = f->start_chunk; c = prev->next; while (c) { c->start_byte = prev->start_byte + prev->length; prev = c; c = c->next; } } void svm_fifo_init_ooo_lookup (svm_fifo_t * f, u8 ooo_type) { if (ooo_type == 0) { ASSERT (!rb_tree_is_init (&f->ooo_enq_lookup)); rb_tree_init (&f->ooo_enq_lookup); } else { ASSERT (!rb_tree_is_init (&f->ooo_deq_lookup)); rb_tree_init (&f->ooo_deq_lookup); } } /** * Creates a fifo in the current heap. Fails vs blow up the process */ svm_fifo_t * svm_fifo_alloc (u32 data_size_in_bytes) { u32 rounded_data_size; svm_fifo_chunk_t *c; svm_fifo_t *f; f = clib_mem_alloc_aligned_or_null (sizeof (*f), CLIB_CACHE_LINE_BYTES); if (f == 0) return 0; clib_memset (f, 0, sizeof (*f)); /* always round fifo data size to the next highest power-of-two */ rounded_data_size = (1 << (max_log2 (data_size_in_bytes))); c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_data_size, CLIB_CACHE_LINE_BYTES); if (!c) { clib_mem_free (f); return 0; } clib_memset (c, 0, sizeof (*c)); c->start_byte = 0; c->length = data_size_in_bytes; c->enq_rb_index = RBTREE_TNIL_INDEX; c->deq_rb_index = RBTREE_TNIL_INDEX; f->start_chunk = f->end_chunk = c; return f; } /** * Creates a fifo chunk in the current heap */ svm_fifo_chunk_t * svm_fifo_chunk_alloc (u32 size) { svm_fifo_chunk_t *c; u32 rounded_size; /* round chunk size to the next highest power-of-two */ rounded_size = (1 << (max_log2 (size))); c = clib_mem_alloc_aligned_or_null (sizeof (*c) + rounded_size, CLIB_CACHE_LINE_BYTES); if (c == 0) return 0; clib_memset (c, 0, sizeof (*c)); c->length = rounded_size; return c; } /** * Find chunk for given byte position * * @param f fifo * @param pos normalized position in fifo * * @return chunk that includes given position or 0 */ static svm_fifo_chunk_t * svm_fifo_find_chunk (svm_fifo_t * f, u32 pos) { svm_fifo_chunk_t *c; c = f->start_chunk; while (c && !f_chunk_includes_pos (c, pos)) c = c->next; return c; } static svm_fifo_chunk_t * svm_fifo_find_next_chunk (svm_fifo_t * f, svm_fifo_chunk_t * start, u32 pos) { svm_fifo_chunk_t *c; ASSERT (start != 0); c = start; while (c && !f_chunk_includes_pos (c, pos)) c = c->next; return c; } u32 svm_fifo_max_read_chunk (svm_fifo_t * f) { u32 head, tail, end_chunk; f_load_head_tail_cons (f, &head, &tail); ASSERT (!f->head_chunk || f_chunk_includes_pos (f->head_chunk, head)); if (!f->head_chunk) { f->head_chunk = svm_fifo_find_chunk (f, head); if (PREDICT_FALSE (!f->head_chunk)) return 0; } end_chunk = f_chunk_end (f->head_chunk); return f_pos_lt (end_chunk, tail) ? end_chunk - head : tail - head; } u32 svm_fifo_max_write_chunk (svm_fifo_t * f) { u32 head, tail; f_load_head_tail_prod (f, &head, &tail); ASSERT (!f->tail_chunk || f_chunk_includes_pos (f->tail_chunk, tail)); return f->tail_chunk ? f_chunk_end (f->tail_chunk) - tail : 0; } static rb_node_t * f_find_node_rbtree (rb_tree_t * rt, u32 pos) { rb_node_t *cur, *prev; cur = rb_node (rt, rt->root); if (PREDICT_FALSE (rb_node_is_tnil (rt, cur))) return 0; while (pos != cur->key) { prev = cur; if (f_pos_lt (pos, cur->key)) { cur = rb_node_left (rt, cur); if (rb_node_is_tnil (rt, cur)) { cur = rb_tree_predecessor (rt, prev); break; } } else { cur = rb_node_right (rt, cur); if (rb_node_is_tnil (rt, cur)) { cur = prev; break; } } } if (rb_node_is_tnil (rt, cur)) return 0; return cur; } static svm_fifo_chunk_t * f_find_chunk_rbtree (rb_tree_t * rt, u32 pos) { svm_fifo_chunk_t *c; rb_node_t *n; if (!rb_tree_is_init (rt)) return 0; n = f_find_node_rbtree (rt, pos); if (!n) return 0; c = uword_to_pointer (n->opaque, svm_fifo_chunk_t *); if (f_chunk_includes_pos (c, pos)) return c; return 0; } static void f_update_ooo_enq (svm_fifo_t * f, u32 start_pos, u32 end_pos) { rb_tree_t *rt = &f->ooo_enq_lookup; svm_fifo_chunk_t *c; rb_node_t *cur; /* Use linear search if rbtree is not initialized */ if (PREDICT_FALSE (!rb_tree_is_init (rt))) { f->ooo_enq = svm_fifo_find_next_chunk (f, f->tail_chunk, start_pos); return; } if (rt->root == RBTREE_TNIL_INDEX) { c = f->tail_chunk; ASSERT (c->enq_rb_index == RBTREE_TNIL_INDEX); c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte, pointer_to_uword (c), f_pos_lt); } else { cur = f_find_node_rbtree (rt, start_pos); c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *); ASSERT (f_pos_leq (c->start_byte, start_pos)); } if (f_chunk_includes_pos (c, start_pos)) f->ooo_enq = c; if (f_chunk_includes_pos (c, end_pos)) return; do { c = c->next; if (!c || c->enq_rb_index != RBTREE_TNIL_INDEX) break; c->enq_rb_index = rb_tree_add_custom (rt, c->start_byte, pointer_to_uword (c), f_pos_lt); if (f_chunk_includes_pos (c, start_pos)) f->ooo_enq = c; } while (!f_chunk_includes_pos (c, end_pos)); } static void f_update_ooo_deq (svm_fifo_t * f, u32 start_pos, u32 end_pos) { rb_tree_t *rt = &f->ooo_deq_lookup; rb_node_t *cur; svm_fifo_chunk_t *c; /* Use linear search if rbtree is not initialized */ if (PREDICT_FALSE (!rb_tree_is_init (rt))) { f->ooo_deq = svm_fifo_find_chunk (f, start_pos); return; } if (rt->root == RBTREE_TNIL_INDEX) { c = f->start_chunk; ASSERT (c->deq_rb_index == RBTREE_TNIL_INDEX); c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte, pointer_to_uword (c), f_pos_lt); } else { cur = f_find_node_rbtree (rt, start_pos); c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *); ASSERT (f_pos_leq (c->start_byte, start_pos)); } if (f_chunk_includes_pos (c, start_pos)) f->ooo_deq = c; if (f_chunk_includes_pos (c, end_pos)) return; do { c = c->next; if (!c || c->deq_rb_index != RBTREE_TNIL_INDEX) break; c->deq_rb_index = rb_tree_add_custom (rt, c->start_byte, pointer_to_uword (c), f_pos_lt); if (f_chunk_includes_pos (c, start_pos)) f->ooo_deq = c; } while (!f_chunk_includes_pos (c, end_pos)); } static svm_fifo_chunk_t * f_lookup_clear_enq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start, u32 end_pos) { rb_tree_t *rt = &f->ooo_enq_lookup; svm_fifo_chunk_t *c; rb_node_t *n; c = start; while (c && !f_chunk_includes_pos (c, end_pos)) { if (c->enq_rb_index != RBTREE_TNIL_INDEX) { n = rb_node (rt, c->enq_rb_index); rb_tree_del_node (rt, n); c->enq_rb_index = RBTREE_TNIL_INDEX; } c = c->next; } /* No ooo segments left, so make sure the current chunk * is not tracked in the enq rbtree */ if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX && c && c->enq_rb_index != RBTREE_TNIL_INDEX) { n = rb_node (rt, c->enq_rb_index); rb_tree_del_node (rt, n); c->enq_rb_index = RBTREE_TNIL_INDEX; } return c; } static svm_fifo_chunk_t * f_lookup_clear_deq_chunks (svm_fifo_t * f, svm_fifo_chunk_t * start, u32 end_pos) { rb_tree_t *rt = &f->ooo_deq_lookup; svm_fifo_chunk_t *c; rb_node_t *n; c = start; while (c && !f_chunk_includes_pos (c, end_pos)) { if (c->deq_rb_index != RBTREE_TNIL_INDEX) { n = rb_node (rt, c->deq_rb_index); rb_tree_del_node (rt, n); c->deq_rb_index = RBTREE_TNIL_INDEX; } c = c->next; } return c; } void svm_fifo_free_chunk_lookup (svm_fifo_t * f) { rb_tree_free_nodes (&f->ooo_enq_lookup); rb_tree_free_nodes (&f->ooo_deq_lookup); } void svm_fifo_free (svm_fifo_t * f) { ASSERT (f->refcnt > 0); if (--f->refcnt == 0) { /* ooo data is not allocated on segment heap */ svm_fifo_free_chunk_lookup (f); clib_mem_free (f); } } void svm_fifo_overwrite_head (svm_fifo_t * f, u8 * src, u32 len) { u32 n_chunk; u32 head, tail, head_idx; svm_fifo_chunk_t *c; ASSERT (len <= f->size); f_load_head_tail_cons (f, &head, &tail); if (!f->head_chunk) f->head_chunk = svm_fifo_find_chunk (f, head); c = f->head_chunk; 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); else { ASSERT (len - n_chunk <= c->next->length); clib_memcpy_fast (&c->data[head_idx], src, n_chunk); clib_memcpy_fast (&c->next->data[0], src + n_chunk, len - n_chunk); } } static int f_try_chunk_alloc (svm_fifo_t * f, u32 head, u32 tail, u32 len) { svm_fifo_chunk_t *c, *cur, *prev; u32 alloc_size, free_alloced; free_alloced = f_chunk_end (f->end_chunk) - tail; alloc_size = clib_min (f->min_alloc, f->size - (tail - head)); alloc_size = clib_max (alloc_size, len - free_alloced); c = fsh_alloc_chunk (f->fs_hdr, f->slice_index, alloc_size); if (PREDICT_FALSE (!c)) return -1; cur = c; prev = f->end_chunk; while (cur) { cur->start_byte = prev->start_byte + prev->length; cur->enq_rb_index = RBTREE_TNIL_INDEX; cur->deq_rb_index = RBTREE_TNIL_INDEX; prev = cur; cur = cur->next; } prev->next = 0; f->end_chunk->next = c; f->end_chunk = prev; if (!f->tail_chunk) f->tail_chunk = c; return 0; } int svm_fifo_enqueue (svm_fifo_t * f, u32 len, const u8 * src) { u32 tail, head, free_count; svm_fifo_chunk_t *old_tail_c; f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; f_load_head_tail_prod (f, &head, &tail); /* free space in fifo can only increase during enqueue: SPSC */ free_count = f_free_count (f, head, tail); if (PREDICT_FALSE (free_count == 0)) return SVM_FIFO_EFULL; /* number of bytes we're going to copy */ len = clib_min (free_count, len); if (f_pos_gt (tail + len, f_chunk_end (f->end_chunk))) { if (PREDICT_FALSE (f_try_chunk_alloc (f, head, tail, len))) { len = f_chunk_end (f->end_chunk) - tail; if (!len) return SVM_FIFO_EGROW; } } old_tail_c = f->tail_chunk; svm_fifo_copy_to_chunk (f, f->tail_chunk, tail, src, len, &f->tail_chunk); tail = tail + len; svm_fifo_trace_add (f, head, len, 2); /* collect out-of-order segments */ if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX)) { len += ooo_segment_try_collect (f, len, &tail); /* Tail chunk might've changed even if nothing was collected */ f->tail_chunk = f_lookup_clear_enq_chunks (f, old_tail_c, tail); f->ooo_enq = 0; } /* store-rel: producer owned index (paired with load-acq in consumer) */ clib_atomic_store_rel_n (&f->tail, tail); return len; } /** * Enqueue a future segment. * * Two choices: either copies the entire segment, or copies nothing * Returns 0 of the entire segment was copied * Returns -1 if none of the segment was copied due to lack of space */ int svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src) { u32 tail, head, free_count, enq_pos; f_load_head_tail_prod (f, &head, &tail); /* free space in fifo can only increase during enqueue: SPSC */ free_count = f_free_count (f, head, tail); f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; /* will this request fit? */ if ((len + offset) > free_count) return SVM_FIFO_EFULL; enq_pos = tail + offset; if (f_pos_gt (enq_pos + len, f_chunk_end (f->end_chunk))) { if (PREDICT_FALSE (f_try_chunk_alloc (f, head, tail, offset + len))) return SVM_FIFO_EGROW; } svm_fifo_trace_add (f, offset, len, 1); ooo_segment_add (f, offset, head, tail, len); if (!f->ooo_enq || !f_chunk_includes_pos (f->ooo_enq, enq_pos)) f_update_ooo_enq (f, enq_pos, enq_pos + len); svm_fifo_copy_to_chunk (f, f->ooo_enq, enq_pos, src, len, &f->ooo_enq); return 0; } /** * Advance tail */ void svm_fifo_enqueue_nocopy (svm_fifo_t * f, u32 len) { u32 tail; ASSERT (len <= svm_fifo_max_enqueue_prod (f)); /* load-relaxed: producer owned index */ tail = f->tail; tail = tail + len; if (rb_tree_is_init (&f->ooo_enq_lookup)) { f->tail_chunk = f_lookup_clear_enq_chunks (f, f->tail_chunk, tail); f->ooo_enq = 0; } else { f->tail_chunk = svm_fifo_find_next_chunk (f, f->tail_chunk, tail); } /* store-rel: producer owned index (paired with load-acq in consumer) */ clib_atomic_store_rel_n (&f->tail, tail); } always_inline svm_fifo_chunk_t * f_unlink_chunks (svm_fifo_t * f, u32 end_pos, u8 maybe_ooo) { svm_fifo_chunk_t *start, *prev = 0, *c; rb_tree_t *rt; rb_node_t *n; ASSERT (!f_chunk_includes_pos (f->start_chunk, end_pos)); if (maybe_ooo) rt = &f->ooo_deq_lookup; c = f->start_chunk; do { if (maybe_ooo && c->deq_rb_index != RBTREE_TNIL_INDEX) { n = rb_node (rt, c->deq_rb_index); ASSERT (n == f_find_node_rbtree (rt, c->start_byte)); rb_tree_del_node (rt, n); c->deq_rb_index = RBTREE_TNIL_INDEX; } if (!c->next) break; prev = c; c = c->next; } while (!f_chunk_includes_pos (c, end_pos)); if (maybe_ooo) { if (f->ooo_deq && f_pos_lt (f->ooo_deq->start_byte, f_chunk_end (c))) f->ooo_deq = 0; } else { if (PREDICT_FALSE (f->ooo_deq != 0)) f->ooo_deq = 0; } /* Avoid unlinking the last chunk */ if (!prev) return 0; prev->next = 0; start = f->start_chunk; f->start_chunk = c; return start; } int svm_fifo_dequeue (svm_fifo_t * f, u32 len, u8 * dst) { u32 tail, head, cursize; f_load_head_tail_cons (f, &head, &tail); /* current size of fifo can only increase during dequeue: SPSC */ cursize = f_cursize (f, head, tail); if (PREDICT_FALSE (cursize == 0)) return SVM_FIFO_EEMPTY; len = clib_min (cursize, len); if (!f->head_chunk) f->head_chunk = svm_fifo_find_chunk (f, head); svm_fifo_copy_from_chunk (f, f->head_chunk, head, dst, len, &f->head_chunk); head = head + len; /* In order dequeues are not supported in combination with ooo peeking. * Use svm_fifo_dequeue_drop instead. */ ASSERT (rb_tree_n_nodes (&f->ooo_deq_lookup) <= 1); if (f_pos_geq (head, f_chunk_end (f->start_chunk))) fsh_collect_chunks (f->fs_hdr, f->slice_index, f_unlink_chunks (f, head, 0)); /* store-rel: consumer owned index (paired with load-acq in producer) */ clib_atomic_store_rel_n (&f->head, head); return len; } int svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst) { u32 tail, head, cursize, head_idx; f_load_head_tail_cons (f, &head, &tail); /* current size of fifo can only increase during peek: SPSC */ cursize = f_cursize (f, head, tail); if (PREDICT_FALSE (cursize < offset)) return SVM_FIFO_EEMPTY; len = clib_min (cursize - offset, len); head_idx = head + offset; if (!f->ooo_deq || !f_chunk_includes_pos (f->ooo_deq, head_idx)) f_update_ooo_deq (f, head_idx, head_idx + len); svm_fifo_copy_from_chunk (f, f->ooo_deq, head_idx, dst, len, &f->ooo_deq); return len; } int svm_fifo_dequeue_drop (svm_fifo_t * f, u32 len) { u32 total_drop_bytes, tail, head, cursize; f_load_head_tail_cons (f, &head, &tail); /* number of bytes available */ cursize = f_cursize (f, head, tail); if (PREDICT_FALSE (cursize == 0)) return SVM_FIFO_EEMPTY; /* number of bytes we're going to drop */ total_drop_bytes = clib_min (cursize, len); svm_fifo_trace_add (f, tail, total_drop_bytes, 3); /* move head */ head = head + total_drop_bytes; if (f_pos_geq (head, f_chunk_end (f->start_chunk))) { fsh_collect_chunks (f->fs_hdr, f->slice_index, f_unlink_chunks (f, head, 1)); f->head_chunk = f_chunk_includes_pos (f->start_chunk, head) ? f->start_chunk : 0; } /* store-rel: consumer owned index (paired with load-acq in producer) */ clib_atomic_store_rel_n (&f->head, head); return total_drop_bytes; } /** * Drop all data from fifo * */ void svm_fifo_dequeue_drop_all (svm_fifo_t * f) { u32 head, tail; f_load_head_tail_all_acq (f, &head, &tail); if (!f->head_chunk || !f_chunk_includes_pos (f->head_chunk, head)) f->head_chunk = svm_fifo_find_chunk (f, head); f->head_chunk = f_lookup_clear_deq_chunks (f, f->head_chunk, tail); if (f_pos_geq (tail, f_chunk_end (f->start_chunk))) fsh_collect_chunks (f->fs_hdr, f->slice_index, f_unlink_chunks (f, tail, 0)); /* store-rel: consumer owned index (paired with load-acq in producer) */ clib_atomic_store_rel_n (&f->head, tail); } int svm_fifo_fill_chunk_list (svm_fifo_t * f) { u32 head, tail; f_load_head_tail_prod (f, &head, &tail); if (f_chunk_end (f->end_chunk) - head >= f->size) return 0; if (f_try_chunk_alloc (f, head, tail, f->size - (tail - head))) return SVM_FIFO_EGROW; return 0; } int svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs) { u32 cursize, head, tail, head_idx; f_load_head_tail_cons (f, &head, &tail); /* consumer function, cursize can only increase while we're working */ cursize = f_cursize (f, head, tail); if (PREDICT_FALSE (cursize == 0)) return SVM_FIFO_EEMPTY; head_idx = head; 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 { fs[0].len = cursize; fs[0].data = f->head_chunk->data + head_idx; fs[1].len = 0; fs[1].data = 0; } 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); } /** * Clones fifo * * Assumptions: * - no prod and cons are accessing either dest or src fifo * - fifo is not multi chunk */ void svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf) { u32 head, tail; /* Support only single chunk clones for now */ ASSERT (svm_fifo_n_chunks (sf) == 1); clib_memcpy_fast (df->head_chunk->data, sf->head_chunk->data, sf->size); f_load_head_tail_all_acq (sf, &head, &tail); clib_atomic_store_rel_n (&df->head, head); clib_atomic_store_rel_n (&df->tail, tail); } u32 svm_fifo_n_ooo_segments (svm_fifo_t * f) { return pool_elts (f->ooo_segments); } ooo_segment_t * 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 head, u32 tail) { svm_fifo_chunk_t *c; clib_atomic_store_rel_n (&f->head, head); clib_atomic_store_rel_n (&f->tail, tail); c = svm_fifo_find_chunk (f, head); ASSERT (c != 0); f->head_chunk = f->ooo_deq = c; c = svm_fifo_find_chunk (f, tail); ASSERT (c != 0); f->tail_chunk = f->ooo_enq = c; } void svm_fifo_add_subscriber (svm_fifo_t * f, u8 subscriber) { if (f->n_subscribers >= SVM_FIFO_MAX_EVT_SUBSCRIBERS) return; f->subscribers[f->n_subscribers++] = subscriber; } void svm_fifo_del_subscriber (svm_fifo_t * f, u8 subscriber) { int i; for (i = 0; i < f->n_subscribers; i++) { if (f->subscribers[i] != subscriber) continue; f->subscribers[i] = f->subscribers[f->n_subscribers - 1]; f->n_subscribers--; break; } } u8 svm_fifo_is_sane (svm_fifo_t * f) { svm_fifo_chunk_t *tmp; if (f->head_chunk && !f_chunk_includes_pos (f->head_chunk, f->head)) return 0; if (f->tail_chunk && !f_chunk_includes_pos (f->tail_chunk, f->tail)) return 0; if (f->ooo_deq) { if (rb_tree_is_init (&f->ooo_deq_lookup)) { if (f_pos_lt (f->ooo_deq->start_byte, f->start_chunk->start_byte) || f_pos_gt (f->ooo_deq->start_byte, f_chunk_end (f->end_chunk))) return 0; tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup, f->ooo_deq->start_byte); } else tmp = svm_fifo_find_chunk (f, f->ooo_deq->start_byte); if (tmp != f->ooo_deq) return 0; } if (f->ooo_enq) { if (rb_tree_is_init (&f->ooo_enq_lookup)) { if (f_pos_lt (f->ooo_enq->start_byte, f->start_chunk->start_byte) || f_pos_gt (f->ooo_enq->start_byte, f_chunk_end (f->end_chunk))) return 0; tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup, f->ooo_enq->start_byte); } else { tmp = svm_fifo_find_next_chunk (f, f->tail_chunk, f->ooo_enq->start_byte); } if (tmp != f->ooo_enq) return 0; } if (f->start_chunk->next) { svm_fifo_chunk_t *c, *prev = 0, *tmp; u32 chunks_bytes = 0; c = f->start_chunk; do { tmp = svm_fifo_find_chunk (f, c->start_byte); if (tmp != c) return 0; if (prev && (prev->start_byte + prev->length != c->start_byte)) return 0; if (c->enq_rb_index != RBTREE_TNIL_INDEX) { tmp = f_find_chunk_rbtree (&f->ooo_enq_lookup, c->start_byte); if (tmp) { if (tmp != c) return 0; } } if (c->deq_rb_index != RBTREE_TNIL_INDEX) { tmp = f_find_chunk_rbtree (&f->ooo_deq_lookup, c->start_byte); if (tmp) { if (tmp != c) return 0; } } chunks_bytes += c->length; prev = c; c = c->next; } while (c); if (chunks_bytes < f->tail - f->head) return 0; } return 1; } u32 svm_fifo_n_chunks (svm_fifo_t * f) { svm_fifo_chunk_t *c; int n_chunks = 0; c = f->start_chunk; while (c) { n_chunks++; c = c->next; } return n_chunks; } u8 * format_ooo_segment (u8 * s, va_list * args) { svm_fifo_t __clib_unused *f = va_arg (*args, svm_fifo_t *); ooo_segment_t *seg = va_arg (*args, ooo_segment_t *); s = format (s, "[%u, %u], len %u, next %d, prev %d", seg->start, seg->start + seg->length, seg->length, seg->next, seg->prev); return s; } u8 * svm_fifo_dump_trace (u8 * s, svm_fifo_t * f) { #if SVM_FIFO_TRACE svm_fifo_trace_elem_t *seg = 0; int i = 0; if (f->trace) { vec_foreach (seg, f->trace) { s = format (s, "{%u, %u, %u}, ", seg->offset, seg->len, seg->action); i++; if (i % 5 == 0) s = format (s, "\n"); } s = format (s, "\n"); } return s; #else return 0; #endif } u8 * svm_fifo_replay (u8 * s, svm_fifo_t * f, u8 no_read, u8 verbose) { int i, trace_len; u8 *data = 0; svm_fifo_trace_elem_t *trace; u32 offset; svm_fifo_t *placeholder_fifo; if (!f) return s; #if SVM_FIFO_TRACE trace = f->trace; trace_len = vec_len (trace); #else trace = 0; trace_len = 0; #endif placeholder_fifo = svm_fifo_alloc (f->size); svm_fifo_init (f, f->size); clib_memset (f->head_chunk->data, 0xFF, f->size); vec_validate (data, f->size); for (i = 0; i < vec_len (data); i++) data[i] = i; for (i = 0; i < trace_len; i++) { offset = trace[i].offset; if (trace[i].action == 1) { if (verbose) s = format (s, "adding [%u, %u]:", trace[i].offset, (trace[i].offset + trace[i].len)); svm_fifo_enqueue_with_offset (placeholder_fifo, trace[i].offset, trace[i].len, &data[offset]); } else if (trace[i].action == 2) { if (verbose) s = format (s, "adding [%u, %u]:", 0, trace[i].len); svm_fifo_enqueue (placeholder_fifo, trace[i].len, &data[offset]); } else if (!no_read) { if (verbose) s = format (s, "read: %u", trace[i].len); svm_fifo_dequeue_drop (placeholder_fifo, trace[i].len); } if (verbose) s = format (s, "%U", format_svm_fifo, placeholder_fifo, 1); } s = format (s, "result: %U", format_svm_fifo, placeholder_fifo, 1); return s; } u8 * format_ooo_list (u8 * s, va_list * args) { svm_fifo_t *f = va_arg (*args, svm_fifo_t *); u32 indent = va_arg (*args, u32); 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%U\n", format_white_space, indent, format_ooo_segment, f, 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); u32 indent; if (!s) return s; indent = format_get_indent (s); s = format (s, "cursize %u nitems %u has_event %d min_alloc %u\n", svm_fifo_max_dequeue (f), f->size, f->has_event, f->min_alloc); s = format (s, "%Uhead %u tail %u segment manager %u\n", format_white_space, indent, f->head, f->tail, f->segment_manager); if (verbose > 1) s = format (s, "%Uvpp session %d thread %d app session %d thread %d\n", format_white_space, indent, f->master_session_index, f->master_thread_index, f->client_session_index, f->client_thread_index); if (verbose) { s = format (s, "%Uooo pool %d active elts newest %u\n", format_white_space, indent, pool_elts (f->ooo_segments), f->ooos_newest); if (svm_fifo_has_ooo_data (f)) s = format (s, " %U", format_ooo_list, f, indent, verbose); } return s; } #endif /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */