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Previously, libports used a hash table per port bucket. This makes
looking up a port difficult if one does not know the port bucket, as
one has to iterate over all buckets and do a hash table lookup each.
Having to iterate over the buckets makes it necessary to keep a list
of all buckets, which has to be updated and protected by a lock as
well.
Also, the current code in _ports_bucket_class_iterate iterates over
the hash table associated with the bucket given. When
ports_class_iterate calls this common function, it obtains a reference
to the bucket from one of the ports in the given class. This will not
work if a class contains ports in different port buckets. This
limitation is not documented as far as I can see. Again, having to
maintain this list has its cost and requires serialization.
Use a global hash table for lookups instead. Keep the per-bucket hash
tables for efficient iteration over buckets. Furthermore, serialize
access to all hash tables using a separate lock. Remove the linked
lists of all buckets and all ports in a class.
* libports/bucket-iterate.c (ports_bucket_iterate): Acquire
_ports_htable_lock. Also, generalize ports_bucket_iterate so that it
takes a pointer to a hash table as first argument.
(ports_bucket_iterate): Ajust call to former function accordingly.
* libports/class-iterate.c (ports_class_iterate): Just call the
generalized _ports_bucket_class_iterate with the global hash table as
argument.
* libports/ports.h (struct port_info): Remove the port class links.
(struct port_bucket): Remove the hash table, and the all buckets link.
(_ports_all_buckets): Remove declaration.
(_ports_htable): New global hash table.
(_ports_htable_lock): Protected by this lock.
* libports/claim-right.c: Adjust accordingly.
* libports/complete-deallocate.c: Likewise.
* libports/create-bucket.c: Likewise.
* libports/create-class.c: Likewise.
* libports/create-internal.c: Likewise.
* libports/destroy-right.c: Likewise.
* libports/import-port.c: Likewise.
* libports/lookup-port.c: Likewise.
* libports/reallocate-from-external.c: Likewise.
* libports/reallocate-port.c: Likewise.
* libports/transfer-right.c: Likewise.
* libports/inhibit-all-rpcs.c: Iterate over the hash table.
* libports/inhibit-bucket-rpcs.c: Likewise, but filter using bucket.
* libports/inhibit-class-rpcs.c: Likewise, but filter using class.
* libports/init.c (_ports_htable): Initialize.
(_ports_htable_lock): Likewise.
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