| Message ID | d42e98ff0760932cffb021eb680b76da74e4461f.1597184949.git.jonathantanmy@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Lazy fetch with subprocess | expand |
Jonathan Tan <jonathantanmy@google.com> writes: > Teach "fetch-pack" not to lazy fetch whenever iterating over > refs. Don't readers need the reason why is it a good thing to do explained here? > This > is done by using the raw form of ref iteration and by dereferencing tags > ourselves. Hmph. The way this patch implements deref_without_lazy_fetch() makes it hard to reuse in other contexts, as it mixes what is done by mark_complete(), which is very much "git fetch" specific. Would "git fetch" be the only user potentially benefit from being able to dereference a tag that already exists locally and ignore missing ones? I wonder if teaching deref_tag() a new flag would be a better alternative to keep the separation of concerns at different layers. > Signed-off-by: Jonathan Tan <jonathantanmy@google.com> > --- > fetch-pack.c | 79 ++++++++++++++++++++++------------------ > t/t5616-partial-clone.sh | 20 ++++++++++ > 2 files changed, 64 insertions(+), 35 deletions(-) > > diff --git a/fetch-pack.c b/fetch-pack.c > index 80fb3bd899..707bbc31fd 100644 > --- a/fetch-pack.c > +++ b/fetch-pack.c > @@ -108,24 +108,48 @@ static void for_each_cached_alternate(struct fetch_negotiator *negotiator, > cb(negotiator, cache.items[i]); > } > > +static struct commit *deref_without_lazy_fetch(const struct object_id *oid, > + int mark_tags_complete) > +{ > + enum object_type type; > + struct object_info info = { .typep = &type }; > + > + while (1) { > + if (oid_object_info_extended(the_repository, oid, &info, > + OBJECT_INFO_SKIP_FETCH_OBJECT | OBJECT_INFO_QUICK)) > + return NULL; > + if (type == OBJ_TAG) { > + struct tag *tag = (struct tag *) > + parse_object(the_repository, oid); > + > + if (!tag->tagged) > + return NULL; > + if (mark_tags_complete) > + tag->object.flags |= COMPLETE; > + oid = &tag->tagged->oid; > + } else { > + break; > + } > + } > + if (type == OBJ_COMMIT) > + return (struct commit *) parse_object(the_repository, oid); > + return NULL; > +} > + > static int rev_list_insert_ref(struct fetch_negotiator *negotiator, > - const char *refname, > const struct object_id *oid) > { > - struct object *o = deref_tag(the_repository, > - parse_object(the_repository, oid), > - refname, 0); > - > - if (o && o->type == OBJ_COMMIT) > - negotiator->add_tip(negotiator, (struct commit *)o); > + struct commit *c = deref_without_lazy_fetch(oid, 0); > > + if (c) > + negotiator->add_tip(negotiator, c); > return 0; > } > > static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid, > int flag, void *cb_data) > { > - return rev_list_insert_ref(cb_data, refname, oid); > + return rev_list_insert_ref(cb_data, oid); > } > > enum ack_type { > @@ -201,7 +225,7 @@ static void send_request(struct fetch_pack_args *args, > static void insert_one_alternate_object(struct fetch_negotiator *negotiator, > struct object *obj) > { > - rev_list_insert_ref(negotiator, NULL, &obj->oid); > + rev_list_insert_ref(negotiator, &obj->oid); > } > > #define INITIAL_FLUSH 16 > @@ -230,13 +254,12 @@ static void mark_tips(struct fetch_negotiator *negotiator, > int i; > > if (!negotiation_tips) { > - for_each_ref(rev_list_insert_ref_oid, negotiator); > + for_each_rawref(rev_list_insert_ref_oid, negotiator); > return; > } > > for (i = 0; i < negotiation_tips->nr; i++) > - rev_list_insert_ref(negotiator, NULL, > - &negotiation_tips->oid[i]); > + rev_list_insert_ref(negotiator, &negotiation_tips->oid[i]); > return; > } > > @@ -503,21 +526,11 @@ static struct commit_list *complete; > > static int mark_complete(const struct object_id *oid) > { > - struct object *o = parse_object(the_repository, oid); > - > - while (o && o->type == OBJ_TAG) { > - struct tag *t = (struct tag *) o; > - if (!t->tagged) > - break; /* broken repository */ > - o->flags |= COMPLETE; > - o = parse_object(the_repository, &t->tagged->oid); > - } > - if (o && o->type == OBJ_COMMIT) { > - struct commit *commit = (struct commit *)o; > - if (!(commit->object.flags & COMPLETE)) { > - commit->object.flags |= COMPLETE; > - commit_list_insert(commit, &complete); > - } > + struct commit *commit = deref_without_lazy_fetch(oid, 1); > + > + if (commit && !(commit->object.flags & COMPLETE)) { > + commit->object.flags |= COMPLETE; > + commit_list_insert(commit, &complete); > } > return 0; > } > @@ -702,7 +715,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator, > */ > trace2_region_enter("fetch-pack", "mark_complete_local_refs", NULL); > if (!args->deepen) { > - for_each_ref(mark_complete_oid, NULL); > + for_each_rawref(mark_complete_oid, NULL); > for_each_cached_alternate(NULL, mark_alternate_complete); > commit_list_sort_by_date(&complete); > if (cutoff) > @@ -716,16 +729,12 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator, > */ > trace2_region_enter("fetch-pack", "mark_common_remote_refs", NULL); > for (ref = *refs; ref; ref = ref->next) { > - struct object *o = deref_tag(the_repository, > - lookup_object(the_repository, > - &ref->old_oid), > - NULL, 0); > + struct commit *c = deref_without_lazy_fetch(&ref->old_oid, 0); > > - if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE)) > + if (!c || !(c->object.flags & COMPLETE)) > continue; > > - negotiator->known_common(negotiator, > - (struct commit *)o); > + negotiator->known_common(negotiator, c); > } > trace2_region_leave("fetch-pack", "mark_common_remote_refs", NULL); > > diff --git a/t/t5616-partial-clone.sh b/t/t5616-partial-clone.sh > index 8a27452a51..e53492d595 100755 > --- a/t/t5616-partial-clone.sh > +++ b/t/t5616-partial-clone.sh > @@ -384,6 +384,26 @@ test_expect_success 'fetch lazy-fetches only to resolve deltas, protocol v2' ' > grep "want $(cat hash)" trace > ' > > +test_expect_success 'fetch does not lazy-fetch missing targets of its refs' ' > + rm -rf server client trace && > + > + test_create_repo server && > + test_config -C server uploadpack.allowfilter 1 && > + test_config -C server uploadpack.allowanysha1inwant 1 && > + test_commit -C server foo && > + > + git clone --filter=blob:none "file://$(pwd)/server" client && > + # Make all refs point to nothing by deleting all objects. > + rm client/.git/objects/pack/* && > + > + test_commit -C server bar && > + GIT_TRACE_PACKET="$(pwd)/trace" git -C client fetch \ > + --no-tags --recurse-submodules=no \ > + origin refs/tags/bar && > + FOO_HASH=$(git -C server rev-parse foo) && > + ! grep "want $FOO_HASH" trace > +' > + > # The following two tests must be in this order. It is important that > # the srv.bare repository did not have tags during clone, but has tags > # in the fetch.
diff --git a/fetch-pack.c b/fetch-pack.c index 80fb3bd899..707bbc31fd 100644 --- a/fetch-pack.c +++ b/fetch-pack.c @@ -108,24 +108,48 @@ static void for_each_cached_alternate(struct fetch_negotiator *negotiator, cb(negotiator, cache.items[i]); } +static struct commit *deref_without_lazy_fetch(const struct object_id *oid, + int mark_tags_complete) +{ + enum object_type type; + struct object_info info = { .typep = &type }; + + while (1) { + if (oid_object_info_extended(the_repository, oid, &info, + OBJECT_INFO_SKIP_FETCH_OBJECT | OBJECT_INFO_QUICK)) + return NULL; + if (type == OBJ_TAG) { + struct tag *tag = (struct tag *) + parse_object(the_repository, oid); + + if (!tag->tagged) + return NULL; + if (mark_tags_complete) + tag->object.flags |= COMPLETE; + oid = &tag->tagged->oid; + } else { + break; + } + } + if (type == OBJ_COMMIT) + return (struct commit *) parse_object(the_repository, oid); + return NULL; +} + static int rev_list_insert_ref(struct fetch_negotiator *negotiator, - const char *refname, const struct object_id *oid) { - struct object *o = deref_tag(the_repository, - parse_object(the_repository, oid), - refname, 0); - - if (o && o->type == OBJ_COMMIT) - negotiator->add_tip(negotiator, (struct commit *)o); + struct commit *c = deref_without_lazy_fetch(oid, 0); + if (c) + negotiator->add_tip(negotiator, c); return 0; } static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid, int flag, void *cb_data) { - return rev_list_insert_ref(cb_data, refname, oid); + return rev_list_insert_ref(cb_data, oid); } enum ack_type { @@ -201,7 +225,7 @@ static void send_request(struct fetch_pack_args *args, static void insert_one_alternate_object(struct fetch_negotiator *negotiator, struct object *obj) { - rev_list_insert_ref(negotiator, NULL, &obj->oid); + rev_list_insert_ref(negotiator, &obj->oid); } #define INITIAL_FLUSH 16 @@ -230,13 +254,12 @@ static void mark_tips(struct fetch_negotiator *negotiator, int i; if (!negotiation_tips) { - for_each_ref(rev_list_insert_ref_oid, negotiator); + for_each_rawref(rev_list_insert_ref_oid, negotiator); return; } for (i = 0; i < negotiation_tips->nr; i++) - rev_list_insert_ref(negotiator, NULL, - &negotiation_tips->oid[i]); + rev_list_insert_ref(negotiator, &negotiation_tips->oid[i]); return; } @@ -503,21 +526,11 @@ static struct commit_list *complete; static int mark_complete(const struct object_id *oid) { - struct object *o = parse_object(the_repository, oid); - - while (o && o->type == OBJ_TAG) { - struct tag *t = (struct tag *) o; - if (!t->tagged) - break; /* broken repository */ - o->flags |= COMPLETE; - o = parse_object(the_repository, &t->tagged->oid); - } - if (o && o->type == OBJ_COMMIT) { - struct commit *commit = (struct commit *)o; - if (!(commit->object.flags & COMPLETE)) { - commit->object.flags |= COMPLETE; - commit_list_insert(commit, &complete); - } + struct commit *commit = deref_without_lazy_fetch(oid, 1); + + if (commit && !(commit->object.flags & COMPLETE)) { + commit->object.flags |= COMPLETE; + commit_list_insert(commit, &complete); } return 0; } @@ -702,7 +715,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator, */ trace2_region_enter("fetch-pack", "mark_complete_local_refs", NULL); if (!args->deepen) { - for_each_ref(mark_complete_oid, NULL); + for_each_rawref(mark_complete_oid, NULL); for_each_cached_alternate(NULL, mark_alternate_complete); commit_list_sort_by_date(&complete); if (cutoff) @@ -716,16 +729,12 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator, */ trace2_region_enter("fetch-pack", "mark_common_remote_refs", NULL); for (ref = *refs; ref; ref = ref->next) { - struct object *o = deref_tag(the_repository, - lookup_object(the_repository, - &ref->old_oid), - NULL, 0); + struct commit *c = deref_without_lazy_fetch(&ref->old_oid, 0); - if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE)) + if (!c || !(c->object.flags & COMPLETE)) continue; - negotiator->known_common(negotiator, - (struct commit *)o); + negotiator->known_common(negotiator, c); } trace2_region_leave("fetch-pack", "mark_common_remote_refs", NULL); diff --git a/t/t5616-partial-clone.sh b/t/t5616-partial-clone.sh index 8a27452a51..e53492d595 100755 --- a/t/t5616-partial-clone.sh +++ b/t/t5616-partial-clone.sh @@ -384,6 +384,26 @@ test_expect_success 'fetch lazy-fetches only to resolve deltas, protocol v2' ' grep "want $(cat hash)" trace ' +test_expect_success 'fetch does not lazy-fetch missing targets of its refs' ' + rm -rf server client trace && + + test_create_repo server && + test_config -C server uploadpack.allowfilter 1 && + test_config -C server uploadpack.allowanysha1inwant 1 && + test_commit -C server foo && + + git clone --filter=blob:none "file://$(pwd)/server" client && + # Make all refs point to nothing by deleting all objects. + rm client/.git/objects/pack/* && + + test_commit -C server bar && + GIT_TRACE_PACKET="$(pwd)/trace" git -C client fetch \ + --no-tags --recurse-submodules=no \ + origin refs/tags/bar && + FOO_HASH=$(git -C server rev-parse foo) && + ! grep "want $FOO_HASH" trace +' + # The following two tests must be in this order. It is important that # the srv.bare repository did not have tags during clone, but has tags # in the fetch.
Teach "fetch-pack" not to lazy fetch whenever iterating over refs. This is done by using the raw form of ref iteration and by dereferencing tags ourselves. Signed-off-by: Jonathan Tan <jonathantanmy@google.com> --- fetch-pack.c | 79 ++++++++++++++++++++++------------------ t/t5616-partial-clone.sh | 20 ++++++++++ 2 files changed, 64 insertions(+), 35 deletions(-)