]> git.ipfire.org Git - thirdparty/git.git/blobdiff - revision.c
Merge branch 'jt/t5500-unflake'
[thirdparty/git.git] / revision.c
index 58f5826df0cce4c22e5813f3475d7d8a9b12bdb0..60cca8c0b9660e5c3e9927da99dee1fcda1c0069 100644 (file)
@@ -29,6 +29,8 @@
 #include "prio-queue.h"
 #include "hashmap.h"
 #include "utf8.h"
+#include "bloom.h"
+#include "json-writer.h"
 
 volatile show_early_output_fn_t show_early_output;
 
@@ -624,11 +626,133 @@ static void file_change(struct diff_options *options,
        options->flags.has_changes = 1;
 }
 
+static int bloom_filter_atexit_registered;
+static unsigned int count_bloom_filter_maybe;
+static unsigned int count_bloom_filter_definitely_not;
+static unsigned int count_bloom_filter_false_positive;
+static unsigned int count_bloom_filter_not_present;
+static unsigned int count_bloom_filter_length_zero;
+
+static void trace2_bloom_filter_statistics_atexit(void)
+{
+       struct json_writer jw = JSON_WRITER_INIT;
+
+       jw_object_begin(&jw, 0);
+       jw_object_intmax(&jw, "filter_not_present", count_bloom_filter_not_present);
+       jw_object_intmax(&jw, "zero_length_filter", count_bloom_filter_length_zero);
+       jw_object_intmax(&jw, "maybe", count_bloom_filter_maybe);
+       jw_object_intmax(&jw, "definitely_not", count_bloom_filter_definitely_not);
+       jw_object_intmax(&jw, "false_positive", count_bloom_filter_false_positive);
+       jw_end(&jw);
+
+       trace2_data_json("bloom", the_repository, "statistics", &jw);
+
+       jw_release(&jw);
+}
+
+static int forbid_bloom_filters(struct pathspec *spec)
+{
+       if (spec->has_wildcard)
+               return 1;
+       if (spec->nr > 1)
+               return 1;
+       if (spec->magic & ~PATHSPEC_LITERAL)
+               return 1;
+       if (spec->nr && (spec->items[0].magic & ~PATHSPEC_LITERAL))
+               return 1;
+
+       return 0;
+}
+
+static void prepare_to_use_bloom_filter(struct rev_info *revs)
+{
+       struct pathspec_item *pi;
+       char *path_alloc = NULL;
+       const char *path;
+       int last_index;
+       int len;
+
+       if (!revs->commits)
+               return;
+
+       if (forbid_bloom_filters(&revs->prune_data))
+               return;
+
+       repo_parse_commit(revs->repo, revs->commits->item);
+
+       if (!revs->repo->objects->commit_graph)
+               return;
+
+       revs->bloom_filter_settings = revs->repo->objects->commit_graph->bloom_filter_settings;
+       if (!revs->bloom_filter_settings)
+               return;
+
+       pi = &revs->pruning.pathspec.items[0];
+       last_index = pi->len - 1;
+
+       /* remove single trailing slash from path, if needed */
+       if (pi->match[last_index] == '/') {
+           path_alloc = xstrdup(pi->match);
+           path_alloc[last_index] = '\0';
+           path = path_alloc;
+       } else
+           path = pi->match;
+
+       len = strlen(path);
+
+       revs->bloom_key = xmalloc(sizeof(struct bloom_key));
+       fill_bloom_key(path, len, revs->bloom_key, revs->bloom_filter_settings);
+
+       if (trace2_is_enabled() && !bloom_filter_atexit_registered) {
+               atexit(trace2_bloom_filter_statistics_atexit);
+               bloom_filter_atexit_registered = 1;
+       }
+
+       free(path_alloc);
+}
+
+static int check_maybe_different_in_bloom_filter(struct rev_info *revs,
+                                                struct commit *commit)
+{
+       struct bloom_filter *filter;
+       int result;
+
+       if (!revs->repo->objects->commit_graph)
+               return -1;
+
+       if (commit->generation == GENERATION_NUMBER_INFINITY)
+               return -1;
+
+       filter = get_bloom_filter(revs->repo, commit, 0);
+
+       if (!filter) {
+               count_bloom_filter_not_present++;
+               return -1;
+       }
+
+       if (!filter->len) {
+               count_bloom_filter_length_zero++;
+               return -1;
+       }
+
+       result = bloom_filter_contains(filter,
+                                      revs->bloom_key,
+                                      revs->bloom_filter_settings);
+
+       if (result)
+               count_bloom_filter_maybe++;
+       else
+               count_bloom_filter_definitely_not++;
+
+       return result;
+}
+
 static int rev_compare_tree(struct rev_info *revs,
-                           struct commit *parent, struct commit *commit)
+                           struct commit *parent, struct commit *commit, int nth_parent)
 {
        struct tree *t1 = get_commit_tree(parent);
        struct tree *t2 = get_commit_tree(commit);
+       int bloom_ret = 1;
 
        if (!t1)
                return REV_TREE_NEW;
@@ -653,11 +777,23 @@ static int rev_compare_tree(struct rev_info *revs,
                        return REV_TREE_SAME;
        }
 
+       if (revs->bloom_key && !nth_parent) {
+               bloom_ret = check_maybe_different_in_bloom_filter(revs, commit);
+
+               if (bloom_ret == 0)
+                       return REV_TREE_SAME;
+       }
+
        tree_difference = REV_TREE_SAME;
        revs->pruning.flags.has_changes = 0;
        if (diff_tree_oid(&t1->object.oid, &t2->object.oid, "",
                           &revs->pruning) < 0)
                return REV_TREE_DIFFERENT;
+
+       if (!nth_parent)
+               if (bloom_ret == 1 && tree_difference == REV_TREE_SAME)
+                       count_bloom_filter_false_positive++;
+
        return tree_difference;
 }
 
@@ -855,7 +991,7 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
                        die("cannot simplify commit %s (because of %s)",
                            oid_to_hex(&commit->object.oid),
                            oid_to_hex(&p->object.oid));
-               switch (rev_compare_tree(revs, p, commit)) {
+               switch (rev_compare_tree(revs, p, commit, nth_parent)) {
                case REV_TREE_SAME:
                        if (!revs->simplify_history || !relevant_commit(p)) {
                                /* Even if a merge with an uninteresting
@@ -870,7 +1006,19 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
                        }
                        parent->next = NULL;
                        commit->parents = parent;
-                       commit->object.flags |= TREESAME;
+
+                       /*
+                        * A merge commit is a "diversion" if it is not
+                        * TREESAME to its first parent but is TREESAME
+                        * to a later parent. In the simplified history,
+                        * we "divert" the history walk to the later
+                        * parent. These commits are shown when "show_pulls"
+                        * is enabled, so do not mark the object as
+                        * TREESAME here.
+                        */
+                       if (!revs->show_pulls || !nth_parent)
+                               commit->object.flags |= TREESAME;
+
                        return;
 
                case REV_TREE_NEW:
@@ -897,6 +1045,10 @@ static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
                                relevant_change = 1;
                        else
                                irrelevant_change = 1;
+
+                       if (!nth_parent)
+                               commit->object.flags |= PULL_MERGE;
+
                        continue;
                }
                die("bad tree compare for commit %s", oid_to_hex(&commit->object.oid));
@@ -2269,6 +2421,8 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
        } else if (!strcmp(arg, "--full-diff")) {
                revs->diff = 1;
                revs->full_diff = 1;
+       } else if (!strcmp(arg, "--show-pulls")) {
+               revs->show_pulls = 1;
        } else if (!strcmp(arg, "--full-history")) {
                revs->simplify_history = 0;
        } else if (!strcmp(arg, "--relative-date")) {
@@ -3023,7 +3177,8 @@ static struct commit_list **simplify_one(struct rev_info *revs, struct commit *c
        if (!cnt ||
            (commit->object.flags & UNINTERESTING) ||
            !(commit->object.flags & TREESAME) ||
-           (parent = one_relevant_parent(revs, commit->parents)) == NULL)
+           (parent = one_relevant_parent(revs, commit->parents)) == NULL ||
+           (revs->show_pulls && (commit->object.flags & PULL_MERGE)))
                st->simplified = commit;
        else {
                pst = locate_simplify_state(revs, parent);
@@ -3366,6 +3521,8 @@ int prepare_revision_walk(struct rev_info *revs)
                                       FOR_EACH_OBJECT_PROMISOR_ONLY);
        }
 
+       if (revs->pruning.pathspec.nr == 1 && !revs->reflog_info)
+               prepare_to_use_bloom_filter(revs);
        if (revs->no_walk != REVISION_WALK_NO_WALK_UNSORTED)
                commit_list_sort_by_date(&revs->commits);
        if (revs->no_walk)
@@ -3383,6 +3540,7 @@ int prepare_revision_walk(struct rev_info *revs)
                simplify_merges(revs);
        if (revs->children.name)
                set_children(revs);
+
        return 0;
 }
 
@@ -3606,6 +3764,10 @@ enum commit_action get_commit_action(struct rev_info *revs, struct commit *commi
                        /* drop merges unless we want parenthood */
                        if (!want_ancestry(revs))
                                return commit_ignore;
+
+                       if (revs->show_pulls && (commit->object.flags & PULL_MERGE))
+                               return commit_show;
+
                        /*
                         * If we want ancestry, then need to keep any merges
                         * between relevant commits to tie together topology.