Re: [PATCH v3 2/5] fetch-pack: load tip_oids eagerly iff needed
- From
Jeff King <peff@peff.net>
- Date
- Oct 4, 2018, 22:07 UTC
- Message-ID
- <20181004220711.GA28287@sigill.intra.peff.net>
- In-Reply-To
- <9f51ac28-73e9-2855-c650-7d695945e286@web.de>
On Thu, Oct 04, 2018 at 05:09:39PM +0200, René Scharfe wrote:
Show 7 quoted lines
> tip_oids_contain() lazily loads refs into an oidset at its first call. > It abuses the internal (sub)member .map.tablesize of that oidset to > check if it has done that already. > > Determine if the oidset needs to be populated upfront and then do that > instead. This duplicates a loop, but simplifies the existing one by > separating concerns between the two.
I like this approach much better than what I showed earlier. But...
Show 18 quoted lines
> diff --git a/fetch-pack.c b/fetch-pack.c
> index 3b317952f0..53914563b5 100644
> --- a/fetch-pack.c
> +++ b/fetch-pack.c
> @@ -526,23 +526,6 @@ static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
> oidset_insert(oids, &refs->old_oid);
> }
>
> -static int tip_oids_contain(struct oidset *tip_oids,
> - struct ref *unmatched, struct ref *newlist,
> - const struct object_id *id)
> -{
> - /*
> - * Note that this only looks at the ref lists the first time it's
> - * called. This works out in filter_refs() because even though it may
> - * add to "newlist" between calls, the additions will always be for
> - * oids that are already in the set.
> - */I don't think the subtle point this comment is making goes away. We're still growing the list in the loop that calls tip_oids_contain() (and which now calls just oidset_contains). That's OK for the reasons given here, but I think that would need to be moved down to this code:
Show 11 quoted lines
> + if (strict) {
> + for (i = 0; i < nr_sought; i++) {
> + ref = sought[i];
> + if (!is_unmatched_ref(ref))
> + continue;
> +
> + add_refs_to_oidset(&tip_oids, unmatched);
> + add_refs_to_oidset(&tip_oids, newlist);
> + break;
> + }
> + }I.e., we need to say here why it's OK to summarize newlist in the oidset, even though we're adding to it later.
-Peff