X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fsvm%2Fsvm_fifo.c;h=c8fd263c09485cb26199ba3ac8e0a5423262e254;hb=b095a3cd221a142f7d2b4897b812b2781de05d29;hp=5c8f244ad2c5e88b6ca7afb2bec894950fa423d2;hpb=93992a9048cb6e5dcd22de5091e72de778122627;p=vpp.git diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c index 5c8f244ad2c..c8fd263c094 100644 --- a/src/svm/svm_fifo.c +++ b/src/svm/svm_fifo.c @@ -1,5 +1,9 @@ /* - * Copyright (c) 2016 Cisco and/or its affiliates. + * 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: @@ -14,19 +18,211 @@ */ #include +#include -#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) +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 (tail_idx >= c->start_byte && 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 (head_idx >= c->start_byte && 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 u8 +position_lt (svm_fifo_t * f, u32 a, u32 b, u32 tail) +{ + return (ooo_segment_distance_from_tail (f, a, tail) + < ooo_segment_distance_from_tail (f, b, tail)); +} + +static inline u8 +position_leq (svm_fifo_t * f, u32 a, u32 b, u32 tail) +{ + return (ooo_segment_distance_from_tail (f, a, tail) + <= ooo_segment_distance_from_tail (f, b, tail)); +} + +static inline u8 +position_gt (svm_fifo_t * f, u32 a, u32 b, u32 tail) +{ + return (ooo_segment_distance_from_tail (f, a, tail) + > ooo_segment_distance_from_tail (f, b, tail)); +} + +static inline u32 +position_diff (svm_fifo_t * f, u32 posa, u32 posb, u32 tail) +{ + return ooo_segment_distance_from_tail (f, posa, tail) + - ooo_segment_distance_from_tail (f, posb, tail); +} + +static inline u32 +ooo_segment_end_pos (svm_fifo_t * f, ooo_segment_t * s) +{ + return s->start + s->length; +} u8 * format_ooo_segment (u8 * s, va_list * args) { + svm_fifo_t *f = va_arg (*args, svm_fifo_t *); ooo_segment_t *seg = va_arg (*args, ooo_segment_t *); + u32 normalized_start = (seg->start + f->nitems - f->tail) % f->size; + s = format (s, "[%u, %u], len %u, next %d, prev %d", normalized_start, + (normalized_start + seg->length) % f->size, 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 *dummy_fifo; + + if (!f) + return s; + +#if SVM_FIFO_TRACE + trace = f->trace; + trace_len = vec_len (trace); +#else + trace = 0; + trace_len = 0; +#endif + + dummy_fifo = svm_fifo_create (f->size); + clib_memset (f->head_chunk->data, 0xFF, f->nitems); + vec_validate (data, f->nitems); + 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) % dummy_fifo->size); + svm_fifo_enqueue_with_offset (dummy_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_nowait (dummy_fifo, trace[i].len, &data[offset]); + } + else if (!no_read) + { + if (verbose) + s = format (s, "read: %u", trace[i].len); + svm_fifo_dequeue_drop (dummy_fifo, trace[i].len); + } + if (verbose) + s = format (s, "%U", format_svm_fifo, dummy_fifo, 1); + } + + s = format (s, "result: %U", format_svm_fifo, dummy_fifo, 1); - s = format (s, "pos %u, len %u, next %d, prev %d", - seg->start, seg->length, seg->next, seg->prev); return s; } @@ -34,15 +230,18 @@ 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\n", format_ooo_segment, seg); + s = format (s, "%U%U\n", format_white_space, indent, format_ooo_segment, + f, seg); ooo_segment_index = seg->next; } + return s; } @@ -51,50 +250,263 @@ 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\n", - f->cursize, f->nitems, f->has_event); - s = format (s, " head %d tail %d\n", f->head, f->tail); + svm_fifo_max_dequeue (f), f->nitems, f->has_event); + s = format (s, "%Uhead %u tail %u segment manager %u\n", format_white_space, + indent, (f->head % f->size), (f->tail % f->size), + f->segment_manager); 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); + 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, " ooo pool %d active elts\n", - pool_elts (f->ooo_segments)); + 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); + s = format (s, " %U", format_ooo_list, f, indent, verbose); } return s; } -/** create an svm fifo, in the current heap. Fails vs blow up the process */ +void +svm_fifo_init (svm_fifo_t * f, u32 size) +{ + f->size = size; + /* + * usable size of the fifo set to rounded_data_size - 1 + * to differentiate between free fifo and empty fifo. + */ + f->nitems = f->size - 1; + f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX; + f->ct_session_index = SVM_FIFO_INVALID_SESSION_INDEX; + f->segment_index = SVM_FIFO_INVALID_INDEX; + f->refcnt = 1; + f->default_chunk.start_byte = 0; + f->default_chunk.length = f->size; + f->default_chunk.next = f->start_chunk = f->end_chunk = &f->default_chunk; + f->head_chunk = f->tail_chunk = f->ooo_enq = f->ooo_deq = f->start_chunk; +} + +/** + * Creates a fifo in the current heap. Fails vs blow up the process + */ svm_fifo_t * svm_fifo_create (u32 data_size_in_bytes) { svm_fifo_t *f; + u32 rounded_data_size; - f = clib_mem_alloc_aligned_or_null (sizeof (*f) + data_size_in_bytes, + /* always round fifo data size to the next highest power-of-two */ + rounded_data_size = (1 << (max_log2 (data_size_in_bytes))); + f = clib_mem_alloc_aligned_or_null (sizeof (*f) + rounded_data_size, CLIB_CACHE_LINE_BYTES); if (f == 0) return 0; - memset (f, 0, sizeof (*f) + data_size_in_bytes); - f->nitems = data_size_in_bytes; - f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX; + clib_memset (f, 0, sizeof (*f)); + svm_fifo_init (f, data_size_in_bytes); + 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; +} + +static inline void +svm_fifo_size_update (svm_fifo_t * f, svm_fifo_chunk_t * c) +{ + svm_fifo_chunk_t *prev; + u32 add_bytes = 0; + + if (!c) + return; + + f->end_chunk->next = c; + while (c) + { + add_bytes += c->length; + prev = c; + c = c->next; + } + f->end_chunk = prev; + prev->next = f->start_chunk; + f->size += add_bytes; + f->nitems = f->size - 1; + f->new_chunks = 0; +} + +static void +svm_fifo_try_size_update (svm_fifo_t * f, u32 new_head) +{ + if (new_head % f->size > f->tail % f->size) + return; - return (f); + svm_fifo_size_update (f, f->new_chunks); + f->flags &= ~SVM_FIFO_F_SIZE_UPDATE; } void -svm_fifo_free (svm_fifo_t * f) +svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c) +{ + svm_fifo_chunk_t *cur, *prev; + + /* Initialize rbtree if needed and add default chunk to it */ + if (!(f->flags & SVM_FIFO_F_MULTI_CHUNK)) + { + rb_tree_init (&f->chunk_lookup); + rb_tree_add2 (&f->chunk_lookup, 0, pointer_to_uword (f->start_chunk)); + f->flags |= SVM_FIFO_F_MULTI_CHUNK; + } + + /* Initialize chunks and add to lookup rbtree. Expectation is that this is + * called with the heap where the rbtree's pool is pushed. */ + cur = c; + if (f->new_chunks) + { + prev = f->new_chunks; + while (prev->next) + prev = prev->next; + prev->next = c; + } + else + prev = f->end_chunk; + + while (cur) + { + cur->start_byte = prev->start_byte + prev->length; + rb_tree_add2 (&f->chunk_lookup, cur->start_byte, + pointer_to_uword (cur)); + prev = cur; + cur = cur->next; + } + + /* If fifo is not wrapped, update the size now */ + if (!svm_fifo_is_wrapped (f)) + { + ASSERT (!f->new_chunks); + svm_fifo_size_update (f, c); + return; + } + + /* Postpone size update */ + if (!f->new_chunks) + { + f->new_chunks = c; + f->flags |= SVM_FIFO_F_SIZE_UPDATE; + } +} + +static inline u8 +svm_fifo_chunk_includes_pos (svm_fifo_chunk_t * c, u32 pos) +{ + return (pos >= c->start_byte && pos < c->start_byte + c->length); +} + +/** + * 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) +{ + rb_tree_t *rt = &f->chunk_lookup; + rb_node_t *cur, *prev; + svm_fifo_chunk_t *c; + + cur = rb_node (rt, rt->root); + while (pos != cur->key) + { + prev = cur; + if (pos < cur->key) + cur = rb_node_left (rt, cur); + else + cur = rb_node_right (rt, cur); + + if (rb_node_is_tnil (rt, cur)) + { + /* Hit tnil as a left child. Find predecessor */ + if (pos < prev->key) + { + cur = rb_tree_predecessor (rt, prev); + c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *); + if (svm_fifo_chunk_includes_pos (c, pos)) + return c; + return 0; + } + /* Hit tnil as a right child. Check if this is the one, otherwise + * search for successor */ + c = uword_to_pointer (prev->opaque, svm_fifo_chunk_t *); + if (svm_fifo_chunk_includes_pos (c, pos)) + return c; + + cur = rb_tree_successor (rt, prev); + c = uword_to_pointer (cur->opaque, svm_fifo_chunk_t *); + if (svm_fifo_chunk_includes_pos (c, pos)) + return c; + return 0; + } + } + + if (!rb_node_is_tnil (rt, cur)) + return uword_to_pointer (cur->opaque, svm_fifo_chunk_t *); + return 0; +} + +void +svm_fifo_free_chunk_lookup (svm_fifo_t * f) +{ + rb_tree_free_nodes (&f->chunk_lookup); +} + +void +svm_fifo_free_ooo_data (svm_fifo_t * f) { pool_free (f->ooo_segments); - clib_mem_free (f); +} + +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); + } } always_inline ooo_segment_t * @@ -142,16 +554,23 @@ ooo_segment_del (svm_fifo_t * f, u32 index) * adjacent segments and removing overlapping ones. */ static void -ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) +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, end_offset, s_sof, s_eof, s_index; + u32 new_index, s_end_pos, s_index; + u32 offset_pos, offset_end_pos; + + ASSERT (offset + length <= ooo_segment_distance_from_tail (f, head, tail) + || head == tail); + + offset_pos = tail + offset; + offset_end_pos = tail + offset + length; - 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, offset, length); + s = ooo_segment_new (f, offset_pos, length); f->ooos_list_head = s - f->ooo_segments; f->ooos_newest = f->ooos_list_head; return; @@ -160,28 +579,30 @@ 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 - && offset_leq (ooo_segment_offset (f, s), offset)) + && position_lt (f, s->start, offset_pos, tail)) 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))) + if (prev + && position_leq (f, offset_pos, ooo_segment_end_pos (f, prev), tail)) { 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_end_pos = ooo_segment_end_pos (f, s); + + /* Since we have previous, offset start position cannot be smaller + * than prev->start. Check tail */ + ASSERT (position_lt (f, s->start, offset_pos, tail)); + 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 (offset_lt (end_offset, s_sof)) + if (position_lt (f, offset_end_pos, s->start, tail)) { - new_s = ooo_segment_new (f, offset, length); + new_s = ooo_segment_new (f, offset_pos, length); new_index = new_s - f->ooo_segments; /* Pool might've moved, get segment again */ @@ -198,28 +619,24 @@ 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 (offset_gt (offset, s_eof)) + else if (position_gt (f, offset_pos, s_end_pos, tail)) { - new_s = ooo_segment_new (f, offset, length); + new_s = ooo_segment_new (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->next != OOO_SEGMENT_INVALID_INDEX) - { - new_s->next = s->next; - next = pool_elt_at_index (f->ooo_segments, new_s->next); - next->prev = new_index; - } + /* Needs to be last */ + ASSERT (s->next == OOO_SEGMENT_INVALID_INDEX); - new_s->prev = s - f->ooo_segments; + new_s->prev = s_index; s->next = new_index; f->ooos_newest = new_index; @@ -230,52 +647,40 @@ ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length) * Merge needed */ -merge: - /* Merge at head */ - if (offset_lt (offset, s_sof)) - { - s->start = offset; - s->length = s_eof - ooo_segment_offset (f, s); - } - /* Last but overlapping previous */ - else if (offset_gt (end_offset, s_eof)) - { - s->length = end_offset - ooo_segment_offset (f, s); - } - /* New segment completely covered by current one */ - else + if (position_lt (f, offset_pos, s->start, tail)) { - /* Do Nothing */ - goto done; + s->start = offset_pos; + s->length = position_diff (f, s_end_pos, s->start, tail); + f->ooos_newest = s - f->ooo_segments; } - /* The new segment's tail may cover multiple smaller ones */ - if (offset_geq (end_offset, s_eof)) +check_tail: + + /* Overlapping tail */ + if (position_gt (f, offset_end_pos, s_end_pos, tail)) { - /* 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)) + s->length = position_diff (f, offset_end_pos, s->start, tail); + + /* Remove the completely overlapped segments in the tail */ + it = ooo_segment_next (f, s); + while (it && position_leq (f, ooo_segment_end_pos (f, it), + offset_end_pos, tail)) { - next = (it->next != OOO_SEGMENT_INVALID_INDEX) ? - pool_elt_at_index (f->ooo_segments, it->next) : 0; + next = ooo_segment_next (f, it); 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)) + if (it && position_leq (f, it->start, offset_end_pos, tail)) { - s->length = ooo_segment_end_offset (f, it) - - ooo_segment_offset (f, s); + s->length = position_diff (f, ooo_segment_end_pos (f, it), + s->start, tail); ooo_segment_del (f, it - f->ooo_segments); } + f->ooos_newest = s - f->ooo_segments; } - -done: - /* Most recently updated segment */ - f->ooos_newest = s - f->ooo_segments; } /** @@ -283,35 +688,30 @@ done: * advanced. Returns the number of bytes added to tail. */ static int -ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued) +ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued, u32 * tail) { ooo_segment_t *s; - u32 index, bytes = 0, diff; - u32 cursize, norm_start, nitems; - - /* current size has not yet been updated */ - cursize = svm_fifo_max_dequeue (f) + n_bytes_enqueued; - nitems = f->nitems; + 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, *tail); - norm_start = s->start % nitems; - diff = (f->nitems + (i32) (f->tail - norm_start)) % nitems; + ASSERT (diff != n_bytes_enqueued); - if (diff > cursize) + if (diff > n_bytes_enqueued) return 0; /* If last tail update overlaps one/multiple ooo segments, remove them */ - while (0 < diff && diff < cursize) + while (0 <= diff && diff < n_bytes_enqueued) { index = s - f->ooo_segments; /* Segment end is beyond the tail. Advance tail and remove segment */ - if (diff < s->length) + if (s->length > diff) { - f->tail += s->length - diff; - f->tail %= f->nitems; bytes = s->length - diff; + *tail = *tail + bytes; ooo_segment_del (f, index); break; } @@ -320,8 +720,7 @@ 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); - norm_start = s->start % nitems; - diff = (f->nitems + (i32) (f->tail - norm_start)) % nitems; + diff = ooo_segment_distance_to_tail (f, s->start, *tail); ooo_segment_del (f, index); } /* End of search */ @@ -332,82 +731,65 @@ 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 = ((nitems - cursize) >= s->length) ? s->length : - nitems - cursize; - - f->tail += bytes; - f->tail %= nitems; + ASSERT (bytes <= f->nitems); + return bytes; +} - ooo_segment_del (f, s - f->ooo_segments); +void +svm_fifo_overwrite_head (svm_fifo_t * f, u8 * data, u32 len) +{ + u32 n_chunk; + u32 head, tail, head_idx; + svm_fifo_chunk_t *c; + + ASSERT (len <= f->nitems); + + f_load_head_tail_cons (f, &head, &tail); + c = f->head_chunk; + head_idx = head % f->size; + head_idx -= c->start_byte; + n_chunk = c->length - head_idx; + if (len <= n_chunk) + clib_memcpy_fast (&c->data[head_idx], data, len); + else + { + clib_memcpy_fast (&c->data[head_idx], data, n_chunk); + clib_memcpy_fast (&c->next->data[0], data + n_chunk, len - n_chunk); } - - return bytes; } -static int -svm_fifo_enqueue_internal (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here) +int +svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 len, const u8 * src) { - u32 total_copy_bytes, first_copy_bytes, second_copy_bytes; - u32 cursize, nitems; + u32 tail, head, free_count; - /* read cursize, which can only increase while we're working */ - cursize = svm_fifo_max_dequeue (f); + f_load_head_tail_prod (f, &head, &tail); - if (PREDICT_FALSE (cursize == f->nitems)) - return -2; /* fifo stuffed */ + /* free space in fifo can only increase during enqueue: SPSC */ + free_count = f_free_count (f, head, tail); - nitems = f->nitems; + f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; - /* Number of bytes we're going to copy */ - total_copy_bytes = (nitems - cursize) < max_bytes ? - (nitems - cursize) : max_bytes; + if (PREDICT_FALSE (free_count == 0)) + return SVM_FIFO_FULL; - if (PREDICT_TRUE (copy_from_here != 0)) - { - /* Number of bytes in first copy segment */ - first_copy_bytes = ((nitems - f->tail) < total_copy_bytes) - ? (nitems - f->tail) : total_copy_bytes; + /* number of bytes we're going to copy */ + len = clib_min (free_count, len); - clib_memcpy (&f->data[f->tail], copy_from_here, first_copy_bytes); - f->tail += first_copy_bytes; - f->tail = (f->tail == nitems) ? 0 : f->tail; + svm_fifo_copy_to_chunk (f, f->tail_chunk, tail % f->size, src, len, + &f->tail_chunk); + tail += len; - /* Number of bytes in second copy segment, if any */ - second_copy_bytes = total_copy_bytes - first_copy_bytes; - if (second_copy_bytes) - { - clib_memcpy (&f->data[f->tail], copy_from_here + first_copy_bytes, - second_copy_bytes); - f->tail += second_copy_bytes; - f->tail = (f->tail == nitems) ? 0 : f->tail; - } - } - else - { - /* Account for a zero-copy enqueue done elsewhere */ - ASSERT (max_bytes <= (nitems - cursize)); - f->tail += max_bytes; - f->tail = f->tail % nitems; - total_copy_bytes = max_bytes; - } + svm_fifo_trace_add (f, head, n_total, 2); - /* Any out-of-order segments to collect? */ + /* collect out-of-order segments */ if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX)) - total_copy_bytes += ooo_segment_try_collect (f, total_copy_bytes); + len += ooo_segment_try_collect (f, len, &tail); - /* Atomically increase the queue length */ - __sync_fetch_and_add (&f->cursize, total_copy_bytes); + /* store-rel: producer owned index (paired with load-acq in consumer) */ + clib_atomic_store_rel_n (&f->tail, tail); - return (total_copy_bytes); -} - -int -svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here) -{ - return svm_fifo_enqueue_internal (f, max_bytes, copy_from_here); + return len; } /** @@ -417,193 +799,181 @@ svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_from_here) * Returns 0 of the entire segment was copied * Returns -1 if none of the segment was copied due to lack of space */ -static int -svm_fifo_enqueue_with_offset_internal (svm_fifo_t * f, - u32 offset, - u32 required_bytes, - u8 * copy_from_here) -{ - u32 total_copy_bytes, first_copy_bytes, second_copy_bytes; - u32 cursize, nitems; - 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? */ - offset_from_tail = (nitems + normalized_offset - f->tail) % nitems; - if ((required_bytes + offset_from_tail) > (nitems - cursize)) - return -1; +int +svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset, u32 len, u8 * src) +{ + u32 tail, head, free_count, tail_idx; - ooo_segment_add (f, offset, required_bytes); + f_load_head_tail_prod (f, &head, &tail); - /* Number of bytes we're going to copy */ - total_copy_bytes = required_bytes; + /* free space in fifo can only increase during enqueue: SPSC */ + free_count = f_free_count (f, head, tail); - /* Number of bytes in first copy segment */ - first_copy_bytes = ((nitems - normalized_offset) < total_copy_bytes) - ? (nitems - normalized_offset) : total_copy_bytes; + /* will this request fit? */ + if ((len + offset) > free_count) + return -1; - clib_memcpy (&f->data[normalized_offset], copy_from_here, first_copy_bytes); + f->ooos_newest = OOO_SEGMENT_INVALID_INDEX; - /* Number of bytes in second copy segment, if any */ - second_copy_bytes = total_copy_bytes - first_copy_bytes; - if (second_copy_bytes) - { - normalized_offset += first_copy_bytes; - normalized_offset %= nitems; + svm_fifo_trace_add (f, offset, len, 1); - ASSERT (normalized_offset == 0); + ooo_segment_add (f, offset, head, tail, len); - clib_memcpy (&f->data[normalized_offset], - copy_from_here + first_copy_bytes, second_copy_bytes); - } + tail_idx = (tail + offset) % f->size; - return (0); -} + if (!svm_fifo_chunk_includes_pos (f->ooo_enq, tail_idx)) + f->ooo_enq = svm_fifo_find_chunk (f, tail_idx); + svm_fifo_copy_to_chunk (f, f->ooo_enq, tail_idx, src, len, &f->ooo_enq); + + return 0; +} int -svm_fifo_enqueue_with_offset (svm_fifo_t * f, - u32 offset, - u32 required_bytes, u8 * copy_from_here) +svm_fifo_dequeue_nowait (svm_fifo_t * f, u32 len, u8 * dst) { - return svm_fifo_enqueue_with_offset_internal (f, offset, required_bytes, - copy_from_here); -} + u32 tail, head, cursize; + f_load_head_tail_cons (f, &head, &tail); -static int -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; + /* current size of fifo can only increase during dequeue: SPSC */ + cursize = f_cursize (f, head, tail); - /* read cursize, which can only increase while we're working */ - cursize = svm_fifo_max_dequeue (f); if (PREDICT_FALSE (cursize == 0)) return -2; /* nothing in the fifo */ - nitems = f->nitems; + len = clib_min (cursize, len); - /* Number of bytes we're going to copy */ - total_copy_bytes = (cursize < max_bytes) ? cursize : max_bytes; + svm_fifo_copy_from_chunk (f, f->head_chunk, head % f->size, dst, len, + &f->head_chunk); + head += len; - if (PREDICT_TRUE (copy_here != 0)) - { - /* Number of bytes in first copy segment */ - first_copy_bytes = ((nitems - f->head) < total_copy_bytes) - ? (nitems - f->head) : total_copy_bytes; - clib_memcpy (copy_here, &f->data[f->head], first_copy_bytes); - f->head += first_copy_bytes; - f->head = (f->head == nitems) ? 0 : f->head; - - /* Number of bytes in second copy segment, if any */ - second_copy_bytes = total_copy_bytes - first_copy_bytes; - if (second_copy_bytes) - { - clib_memcpy (copy_here + first_copy_bytes, - &f->data[f->head], second_copy_bytes); - f->head += second_copy_bytes; - f->head = (f->head == nitems) ? 0 : f->head; - } - } - else - { - /* Account for a zero-copy dequeue done elsewhere */ - ASSERT (max_bytes <= cursize); - f->head += max_bytes; - f->head = f->head % nitems; - cursize -= max_bytes; - total_copy_bytes = max_bytes; - } + if (PREDICT_FALSE (f->flags & SVM_FIFO_F_SIZE_UPDATE)) + svm_fifo_try_size_update (f, head); - __sync_fetch_and_sub (&f->cursize, total_copy_bytes); + /* store-rel: consumer owned index (paired with load-acq in producer) */ + clib_atomic_store_rel_n (&f->head, head); - return (total_copy_bytes); + return len; } int -svm_fifo_dequeue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_here) +svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 len, u8 * dst) { - return svm_fifo_dequeue_internal (f, max_bytes, copy_here); -} + u32 tail, head, cursize, head_idx; -int -svm_fifo_peek (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; + f_load_head_tail_cons (f, &head, &tail); - /* read cursize, which can only increase while we're working */ - cursize = svm_fifo_max_dequeue (f); - if (PREDICT_FALSE (cursize < relative_offset)) - return -2; /* nothing in the fifo */ + /* current size of fifo can only increase during peek: SPSC */ + cursize = f_cursize (f, head, tail); - nitems = f->nitems; - real_head = f->head + relative_offset; - real_head = real_head >= nitems ? real_head - nitems : real_head; + if (PREDICT_FALSE (cursize < offset)) + return -2; /* nothing in the fifo */ - /* Number of bytes we're going to copy */ - total_copy_bytes = (cursize - relative_offset < max_bytes) ? - cursize - relative_offset : max_bytes; + len = clib_min (cursize - offset, len); + 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); - if (PREDICT_TRUE (copy_here != 0)) - { - /* Number of bytes in first copy segment */ - first_copy_bytes = - ((nitems - real_head) < total_copy_bytes) ? - (nitems - real_head) : total_copy_bytes; - clib_memcpy (copy_here, &f->data[real_head], 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) - { - clib_memcpy (copy_here + first_copy_bytes, &f->data[0], - second_copy_bytes); - } - } - return total_copy_bytes; + 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 max_bytes) { - u32 total_drop_bytes, first_drop_bytes, second_drop_bytes; - u32 cursize, nitems; + u32 total_drop_bytes; + u32 tail, head, cursize; + + f_load_head_tail_cons (f, &head, &tail); + + /* number of bytes we're going to drop */ + cursize = f_cursize (f, head, tail); - /* read cursize, which can only increase while we're working */ - cursize = svm_fifo_max_dequeue (f); if (PREDICT_FALSE (cursize == 0)) return -2; /* nothing in the fifo */ - nitems = f->nitems; + svm_fifo_trace_add (f, tail, total_drop_bytes, 3); - /* Number of bytes we're going to drop */ + /* number of bytes we're going to drop */ total_drop_bytes = (cursize < max_bytes) ? cursize : max_bytes; - /* Number of bytes in first copy segment */ - first_drop_bytes = - ((nitems - f->head) < total_drop_bytes) ? - (nitems - f->head) : total_drop_bytes; - f->head += first_drop_bytes; - f->head = (f->head == nitems) ? 0 : f->head; + /* move head */ + head += total_drop_bytes; + + ASSERT (cursize >= total_drop_bytes); + /* store-rel: consumer owned index (paired with load-acq in producer) */ + clib_atomic_store_rel_n (&f->head, head); + + return total_drop_bytes; +} + +void +svm_fifo_dequeue_drop_all (svm_fifo_t * f) +{ + /* consumer foreign index */ + u32 tail = clib_atomic_load_acq_n (&f->tail); + /* store-rel: consumer owned index (paired with load-acq in producer) */ + clib_atomic_store_rel_n (&f->head, tail); +} + +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); - /* Number of bytes in second drop segment, if any */ - second_drop_bytes = total_drop_bytes - first_drop_bytes; - if (second_drop_bytes) + if (PREDICT_FALSE (cursize == 0)) + return -2; /* nothing in the fifo */ + + head_idx = head % f->size; + + if (tail < head) { - f->head += second_drop_bytes; - f->head = (f->head == nitems) ? 0 : f->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, head_idx; - __sync_fetch_and_sub (&f->cursize, total_drop_bytes); + /* consumer owned index */ + head = f->head; + head_idx = head % f->size; - return total_drop_bytes; + ASSERT (fs[0].data == f->head_chunk->data + head_idx); + 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); +} + +/* Assumption: no prod and cons are accessing either dest or src fifo */ +void +svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf) +{ + u32 head, tail; + 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 @@ -622,11 +992,46 @@ svm_fifo_first_ooo_segment (svm_fifo_t * f) * Set fifo pointers to requested offset */ void -svm_fifo_init_pointers (svm_fifo_t * f, u32 pointer) +svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail) +{ + 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); + ASSERT (c != 0); + f->head_chunk = f->ooo_deq = c; + c = svm_fifo_find_chunk (f, tail % f->size); + 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) { - f->head = f->tail = pointer % f->nitems; + 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; + } } +#endif /* * fd.io coding-style-patch-verification: ON *