From patchwork Mon Aug 30 14:57:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Han-Wen Nienhuys X-Patchwork-Id: 12465407 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=-12.8 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 8BF9AC432BE for ; Mon, 30 Aug 2021 14:58:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6DB6860E77 for ; Mon, 30 Aug 2021 14:58:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237358AbhH3O7I (ORCPT ); Mon, 30 Aug 2021 10:59:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55552 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237305AbhH3O66 (ORCPT ); Mon, 30 Aug 2021 10:58:58 -0400 Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A818C06175F for ; Mon, 30 Aug 2021 07:58:04 -0700 (PDT) Received: by mail-wr1-x42f.google.com with SMTP id d26so22974490wrc.0 for ; Mon, 30 Aug 2021 07:58:04 -0700 (PDT) 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=FrBrCx9Fa7CZ3etygCJp/FvxBrRfhn+6RYsFjEAmHJc=; b=LS+3dFa5XtWi73UsdfV8Yl2j5YDsrm25HxS6bewxhuygD3wcNI8DEk7QCHxmYJWMFS jyFwYtOClrg8up8QjU2turO+LaJAkNEqC5A2Mh39ilfdAScnuXxitKPJU9F9CDSGsSDE kZn/LuuXzYTFC/6waeejj9g5W9aMM9KVlzNSU5VRN1eJQCdVs2EI166AAoZ85SkNzGCL BhhZJWnOSIFhtwmzT782CzZyJGey/jSoqN6xyrxbdj7aPtrCsEWbuZigVBr60WXxrXb5 ZdpgujrgRhKJJ6wCeFLVCgiCzSr85r+m/CjV48c5NcIPSV/jxnKoyvjDgel3VNRyOpn8 EbjA== 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=FrBrCx9Fa7CZ3etygCJp/FvxBrRfhn+6RYsFjEAmHJc=; b=Ks1ucAoBrmTv6ddraFkFVUUDilparVrKSR/2fYs1DlEsP7KkKtZLnAb1fOQvS3jXaI nuXyPnI1PS3ST2s2ilP27CJL4fFzJcaRys1AAmYqN4jRnGFZLspTUoQG7yTmC1l26loh nNG+Ha7PM5UY+ywG4+LwKrNPy/PcoT1qPfKART78SiD9SsYgKr65X2yxF7QB+eeGAUXI jx3DKvi+FFpcSTqmIGVzCYg+2zgH1jlaGKruugMMQYCCvo/oy/6YSM478WNDV6XRGApa +9lBSa1/dpDHGRPHSGQ/4mMTovRJh4Llboai1zblH6mLpuAZppa8pK5ESaaXMn6am+18 zfCQ== X-Gm-Message-State: AOAM5314xgV0tnleb9PrT1uSYtJl3/tnUHRBY9p/HRgB//VYinpf9MdH rN8YIqtbQji8flIDOfhZ3k8moyqWXiY= X-Google-Smtp-Source: ABdhPJzjebeQrryFgn8U7hdCJCc7gx770ouNEX8N357dLCd9bU/48sjaliv9H+IRR22VqofDSFA8pA== X-Received: by 2002:adf:e68b:: with SMTP id r11mr26488586wrm.394.1630335482758; Mon, 30 Aug 2021 07:58:02 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id m3sm19888760wrg.45.2021.08.30.07.58.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Aug 2021 07:58:02 -0700 (PDT) Message-Id: <49a9a00465dc65463eec44089f9b571a2145901d.1630335476.git.gitgitgadget@gmail.com> In-Reply-To: References: Date: Mon, 30 Aug 2021 14:57:45 +0000 Subject: [PATCH 09/19] reftable: a generic binary tree implementation Fcc: Sent MIME-Version: 1.0 To: git@vger.kernel.org Cc: 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 65bd39ecdc0..2e5a9f40ed1 100644 --- a/Makefile +++ b/Makefile @@ -2462,11 +2462,13 @@ 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_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)) diff --git a/reftable/tree.c b/reftable/tree.c new file mode 100644 index 00000000000..82db7995dd6 --- /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) { + infix_walk(t->left, action, arg); + } + action(arg, t->key); + if (t->right) { + infix_walk(t->right, action, arg); + } +} + +void tree_free(struct tree_node *t) +{ + if (t == NULL) { + return; + } + if (t->left) { + tree_free(t->left); + } + if (t->right) { + 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..09a970e17b9 --- /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 = arg; + if (c->last) { + 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; }