From: Eric Anholt Date: Wed, 27 Feb 2019 19:12:59 +0000 (-0800) Subject: util: Add a DAG datastructure. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0533d2d95c0df559e78de3bfeb8e8ae5b7fc8140;p=mesa.git util: Add a DAG datastructure. I keep writing this for various schedulers. Acked-by: Timothy Arceri --- diff --git a/src/util/Makefile.sources b/src/util/Makefile.sources index f09b89b3be5..541cb6b85be 100644 --- a/src/util/Makefile.sources +++ b/src/util/Makefile.sources @@ -7,6 +7,8 @@ MESA_UTIL_FILES := \ build_id.h \ crc32.c \ crc32.h \ + dag.c \ + dag.h \ debug.c \ debug.h \ disk_cache.c \ diff --git a/src/util/dag.c b/src/util/dag.c new file mode 100644 index 00000000000..8f7cdd6348e --- /dev/null +++ b/src/util/dag.c @@ -0,0 +1,154 @@ +/* + * Copyright © 2019 Broadcom + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include "util/set.h" +#include "util/dag.h" + +/** + * Adds a directed edge from the parent node to the child. + * + * Both nodes should have been initialized with dag_init_node(). The edge + * list may contain multiple edges to the same child with different data. + */ +void +dag_add_edge(struct dag_node *parent, struct dag_node *child, void *data) +{ + util_dynarray_foreach(&parent->edges, struct dag_edge, edge) { + if (edge->child == child && edge->data == data) + return; + } + /* Remove the child as a DAG head. */ + list_delinit(&child->link); + + struct dag_edge edge = { + .child = child, + .data = data, + }; + + util_dynarray_append(&parent->edges, struct dag_edge, edge); + child->parent_count++; +} + +/* Removes a single edge from the graph, promoting the child to a DAG head. + * + * Note that calling this other than through dag_prune_head() means that you + * need to be careful when iterating the edges of remaining nodes for NULL + * children. + */ +void +dag_remove_edge(struct dag *dag, struct dag_edge *edge) +{ + if (!edge->child) + return; + + struct dag_node *child = edge->child; + child->parent_count--; + if (child->parent_count == 0) + list_addtail(&child->link, &dag->heads); + + edge->child = NULL; + edge->data = NULL; +} + +/** + * Removes a DAG head from the graph, and moves any new dag heads into the + * heads list. + */ +void +dag_prune_head(struct dag *dag, struct dag_node *node) +{ + assert(!node->parent_count); + + list_delinit(&node->link); + + util_dynarray_foreach(&node->edges, struct dag_edge, edge) { + dag_remove_edge(dag, edge); + } +} + +/** + * Initializes DAG node (probably embedded in some other datastructure in the + * user). + */ +void +dag_init_node(struct dag *dag, struct dag_node *node) +{ + util_dynarray_init(&node->edges, dag); + list_addtail(&node->link, &dag->heads); +} + +struct dag_traverse_bottom_up_state { + struct set *seen; + void *data; +}; + +static void +dag_traverse_bottom_up_node(struct dag_node *node, + void (*cb)(struct dag_node *node, + void *data), + struct dag_traverse_bottom_up_state *state) +{ + if (_mesa_set_search(state->seen, node)) + return; + + util_dynarray_foreach(&node->edges, struct dag_edge, edge) { + dag_traverse_bottom_up_node(edge->child, cb, state); + } + + cb(node, state->data); + _mesa_set_add(state->seen, node); +} + +/** + * Walks the DAG from leaves to the root, ensuring that each node is only seen + * once its children have been, and each node is only traversed once. + */ +void +dag_traverse_bottom_up(struct dag *dag, void (*cb)(struct dag_node *node, + void *data), void *data) +{ + struct dag_traverse_bottom_up_state state = { + .seen = _mesa_pointer_set_create(NULL), + .data = data, + }; + + list_for_each_entry(struct dag_node, node, &dag->heads, link) { + dag_traverse_bottom_up_node(node, cb, &state); + } + + ralloc_free(state.seen); +} + +/** + * Creates an empty DAG datastructure. + */ +struct dag * +dag_create(void *mem_ctx) +{ + struct dag *dag = rzalloc(mem_ctx, struct dag); + + list_inithead(&dag->heads); + + return dag; +} + diff --git a/src/util/dag.h b/src/util/dag.h new file mode 100644 index 00000000000..bb46b483972 --- /dev/null +++ b/src/util/dag.h @@ -0,0 +1,65 @@ +/* + * Copyright © 2019 Broadcom + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#ifndef DAG_H +#define DAG_H + +#include +#include "util/list.h" +#include "util/u_dynarray.h" + +#ifdef __cplusplus +extern "C" { +#endif + +struct dag_edge { + struct dag_node *child; + /* User-defined data associated with the edge. */ + void *data; +}; + +struct dag_node { + /* Position in the DAG heads list (or a self-link) */ + struct list_head link; + /* Array struct edge to the children. */ + struct util_dynarray edges; + uint32_t parent_count; +}; + +struct dag { + struct list_head heads; +}; + +struct dag *dag_create(void *mem_ctx); +void dag_init_node(struct dag *dag, struct dag_node *node); +void dag_add_edge(struct dag_node *parent, struct dag_node *child, void *data); +void dag_remove_edge(struct dag *dag, struct dag_edge *edge); +void dag_traverse_bottom_up(struct dag *dag, void (*cb)(struct dag_node *node, + void *data), void *data); +void dag_prune_head(struct dag *dag, struct dag_node *node); + +#ifdef __cplusplus +} +#endif + +#endif diff --git a/src/util/meson.build b/src/util/meson.build index 4f64681f191..322c75e5985 100644 --- a/src/util/meson.build +++ b/src/util/meson.build @@ -31,6 +31,7 @@ files_mesa_util = files( 'build_id.h', 'crc32.c', 'crc32.h', + 'dag.c', 'debug.c', 'debug.h', 'disk_cache.c',