From patchwork Wed Dec 9 14:00:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Han-Wen Nienhuys X-Patchwork-Id: 11961579 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5EC5C4361B for ; Wed, 9 Dec 2020 14:03:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2AC823B31 for ; Wed, 9 Dec 2020 14:03:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727906AbgLIOC7 (ORCPT ); Wed, 9 Dec 2020 09:02:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732781AbgLIOB5 (ORCPT ); Wed, 9 Dec 2020 09:01:57 -0500 Received: from mail-wr1-x433.google.com (mail-wr1-x433.google.com [IPv6:2a00:1450:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E3EB2C061285 for ; Wed, 9 Dec 2020 06:00:40 -0800 (PST) Received: by mail-wr1-x433.google.com with SMTP id x6so1846816wro.11 for ; Wed, 09 Dec 2020 06:00:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=kmTaSl1V6fQm6G4+IW71nCIJW8ZmPn8MUkbzlmuR2Xs=; b=gJ082F5Tsh4XyieqCY8/DO34R5mjM6uAFYCxN3+praKZbim8uOvaCaCFP4cVT2Azc0 mHYHFj0/AHeET0UZYJqj8oDRdD/GQfiY4TG7vlJFu0+zLwDIY7dUYwcl+flfr3rv2q5A u6zCroeKw+nsb2I4+PaQE+xaNvoa4Qqp0w0UQc21zH+AnZ0N0J51WLicFhGnSHj2IrX8 dL2cPmw9C4BeElhptfVJU4HiYmfD86xtUN2Oaji87/bZvVVEA/6NvNrdCazYiE/6Xrwk x1ZJTX9CB5LGFl3L5RA0yPXZDMfJVjyu+35j1O+/cty6+ZYXAr7Znlo6EJgEkU31LwQQ 5JDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=kmTaSl1V6fQm6G4+IW71nCIJW8ZmPn8MUkbzlmuR2Xs=; b=MbGwV40grmg6689FNQ0AbYcG7iqH/aVpZEGo321QIGKLLre+Mi/TQJXfJQEtCaREo/ xqKdSzX1p1k06V+1t9e29lfHIMHW6NEBfpVkoF88HmEULZMdyuK+KhWMdHfqTIEOTJj+ Rjmd55fqW8hvjMyn2EmtkN1yqV9fxKLH1jN+EjTxp89r5w/NFP7NSRgvpaNJ+m3X4QYQ HSFT3Jrbi23gNVLWohQ2q8fosoxOX73Hiau0QwhC+pZs4M9cgYzMg7ljgMWfWoPqToVf Iklnau1NT6MsfJzO5sRDliER7M14M91pnb4vBRNnE1qCssz4L9SHVp3cW7jX8+l3RFaT Uxhg== X-Gm-Message-State: AOAM531lsx0hkjk4vEbEtIs9RTUFszq4BR3xUAmeY8Y9MBHWnwF8LzzU 5tIUf7VMtTs0it5BB8736zLy7RNqIuI= X-Google-Smtp-Source: ABdhPJy+fFN4k4NYbAJW+51wFFpKbj0H3cNVQgf6/EiEJEQwujlSVQFr/243LCgvyagUu8fbtreo5w== X-Received: by 2002:adf:9b91:: with SMTP id d17mr2887751wrc.32.1607522439399; Wed, 09 Dec 2020 06:00:39 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id h5sm4003637wrp.56.2020.12.09.06.00.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Dec 2020 06:00:38 -0800 (PST) Message-Id: <6968dbc3828f22369cc92bf56e3a7855769415fa.1607522429.git.gitgitgadget@gmail.com> In-Reply-To: References: Date: Wed, 09 Dec 2020 14:00:22 +0000 Subject: [PATCH v4 08/15] reftable: a generic binary tree implementation Fcc: Sent MIME-Version: 1.0 To: git@vger.kernel.org Cc: Han-Wen Nienhuys , Jeff King , Ramsay Jones , Jonathan Nieder , Johannes Schindelin , Jonathan Tan , Josh Steadmon , Emily Shaffer , Patrick Steinhardt , =?utf-8?b?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason , Felipe Contreras , Han-Wen Nienhuys , Han-Wen Nienhuys Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Han-Wen Nienhuys From: Han-Wen Nienhuys The reftable format includes support for an (OID => ref) map. This map can speed up visibility and reachability checks. In particular, various operations along the fetch/push path within Gerrit have ben sped up by using this structure. The map is constructed with help of a binary tree. Object IDs are hashes, so they are uniformly distributed. Hence, the tree does not attempt forced rebalancing. Signed-off-by: Han-Wen Nienhuys --- Makefile | 4 ++- reftable/tree.c | 63 ++++++++++++++++++++++++++++++++++++++++ reftable/tree.h | 34 ++++++++++++++++++++++ reftable/tree_test.c | 61 ++++++++++++++++++++++++++++++++++++++ t/helper/test-reftable.c | 1 + 5 files changed, 162 insertions(+), 1 deletion(-) create mode 100644 reftable/tree.c create mode 100644 reftable/tree.h create mode 100644 reftable/tree_test.c diff --git a/Makefile b/Makefile index abe0dda5777..734c05655b2 100644 --- a/Makefile +++ b/Makefile @@ -2395,12 +2395,14 @@ REFTABLE_OBJS += reftable/block.o REFTABLE_OBJS += reftable/blocksource.o REFTABLE_OBJS += reftable/publicbasics.o REFTABLE_OBJS += reftable/record.o +REFTABLE_OBJS += reftable/tree.o REFTABLE_OBJS += reftable/zlib-compat.o +REFTABLE_TEST_OBJS += reftable/basics_test.o REFTABLE_TEST_OBJS += reftable/block_test.o REFTABLE_TEST_OBJS += reftable/record_test.o REFTABLE_TEST_OBJS += reftable/test_framework.o -REFTABLE_TEST_OBJS += reftable/basics_test.o +REFTABLE_TEST_OBJS += reftable/tree_test.o TEST_OBJS := $(patsubst %$X,%.o,$(TEST_PROGRAMS)) $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS)) OBJECTS := $(LIB_OBJS) $(BUILTIN_OBJS) $(PROGRAM_OBJS) $(TEST_OBJS) \ diff --git a/reftable/tree.c b/reftable/tree.c new file mode 100644 index 00000000000..0061d14e306 --- /dev/null +++ b/reftable/tree.c @@ -0,0 +1,63 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "tree.h" + +#include "basics.h" +#include "system.h" + +struct tree_node *tree_search(void *key, struct tree_node **rootp, + int (*compare)(const void *, const void *), + int insert) +{ + int res; + if (*rootp == NULL) { + if (!insert) { + return NULL; + } else { + struct tree_node *n = + reftable_calloc(sizeof(struct tree_node)); + n->key = key; + *rootp = n; + return *rootp; + } + } + + res = compare(key, (*rootp)->key); + if (res < 0) + return tree_search(key, &(*rootp)->left, compare, insert); + else if (res > 0) + return tree_search(key, &(*rootp)->right, compare, insert); + return *rootp; +} + +void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key), + void *arg) +{ + if (t->left != NULL) { + infix_walk(t->left, action, arg); + } + action(arg, t->key); + if (t->right != NULL) { + infix_walk(t->right, action, arg); + } +} + +void tree_free(struct tree_node *t) +{ + if (t == NULL) { + return; + } + if (t->left != NULL) { + tree_free(t->left); + } + if (t->right != NULL) { + tree_free(t->right); + } + reftable_free(t); +} diff --git a/reftable/tree.h b/reftable/tree.h new file mode 100644 index 00000000000..fbdd002e23a --- /dev/null +++ b/reftable/tree.h @@ -0,0 +1,34 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef TREE_H +#define TREE_H + +/* tree_node is a generic binary search tree. */ +struct tree_node { + void *key; + struct tree_node *left, *right; +}; + +/* looks for `key` in `rootp` using `compare` as comparison function. If insert + * is set, insert the key if it's not found. Else, return NULL. + */ +struct tree_node *tree_search(void *key, struct tree_node **rootp, + int (*compare)(const void *, const void *), + int insert); + +/* performs an infix walk of the tree. */ +void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key), + void *arg); + +/* + * deallocates the tree nodes recursively. Keys should be deallocated separately + * by walking over the tree. */ +void tree_free(struct tree_node *t); + +#endif diff --git a/reftable/tree_test.c b/reftable/tree_test.c new file mode 100644 index 00000000000..26d1e694252 --- /dev/null +++ b/reftable/tree_test.c @@ -0,0 +1,61 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "tree.h" + +#include "basics.h" +#include "record.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static int test_compare(const void *a, const void *b) +{ + return (char *)a - (char *)b; +} + +struct curry { + void *last; +}; + +static void check_increasing(void *arg, void *key) +{ + struct curry *c = (struct curry *)arg; + if (c->last != NULL) { + assert(test_compare(c->last, key) < 0); + } + c->last = key; +} + +static void test_tree(void) +{ + struct tree_node *root = NULL; + + void *values[11] = { NULL }; + struct tree_node *nodes[11] = { NULL }; + int i = 1; + struct curry c = { NULL }; + do { + nodes[i] = tree_search(values + i, &root, &test_compare, 1); + i = (i * 7) % 11; + } while (i != 1); + + for (i = 1; i < ARRAY_SIZE(nodes); i++) { + assert(values + i == nodes[i]->key); + assert(nodes[i] == + tree_search(values + i, &root, &test_compare, 0)); + } + + infix_walk(root, check_increasing, &c); + tree_free(root); +} + +int tree_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_tree); + return 0; +} diff --git a/t/helper/test-reftable.c b/t/helper/test-reftable.c index c9deeaf08c7..050551fa698 100644 --- a/t/helper/test-reftable.c +++ b/t/helper/test-reftable.c @@ -6,5 +6,6 @@ int cmd__reftable(int argc, const char **argv) basics_test_main(argc, argv); block_test_main(argc, argv); record_test_main(argc, argv); + tree_test_main(argc, argv); return 0; }