This array of tranche names is looking pretty ugly these days, and it'll get worse as we add more members to it. I propose to use C99 designated initializers, like we've done for other arrays. Patch attached.
The way I've coded in this patch, it means the array will now have 52 NULL pointers at the beginning. I don't think this is a big deal and makes the code prettier. I see two alternatives: 1. Avoid all those NULLs by making each definition uglier (subtract NUM_INDIVIDUAL_LWLOCKS from each array index) _and_ the usage of the array by subtracting the same amount. This saves 208 bytes at the expense of making the code worse. 2. More invasively, rework generate-lwlocknames.pl so that both lwlocks and these builtin tranche names appear in a single array. (We could do so by #include'ing lwlocknames.c at the top of the array). Now, having written this proposal, I'm leaning towards idea 2 myself, but since the patch here is less invasive, it seems worth having as evidence. -- Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/ "People get annoyed when you try to debug them." (Larry Wall)
>From 037fc293b359fbe7dfffcdaf8d5816daa82c0ddd Mon Sep 17 00:00:00 2001 From: Alvaro Herrera <alvhe...@alvh.no-ip.org> Date: Tue, 23 Jan 2024 10:36:14 +0100 Subject: [PATCH] Use designated initializers for BuiltinTrancheNames --- src/backend/storage/lmgr/lwlock.c | 97 +++++++++++-------------------- 1 file changed, 33 insertions(+), 64 deletions(-) diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c index 2f2de5a562..98fa6035cc 100644 --- a/src/backend/storage/lmgr/lwlock.c +++ b/src/backend/storage/lmgr/lwlock.c @@ -132,72 +132,41 @@ StaticAssertDecl(LW_VAL_EXCLUSIVE > (uint32) MAX_BACKENDS, extern const char *const IndividualLWLockNames[]; /* in lwlocknames.c */ static const char *const BuiltinTrancheNames[] = { - /* LWTRANCHE_XACT_BUFFER: */ - "XactBuffer", - /* LWTRANCHE_COMMITTS_BUFFER: */ - "CommitTsBuffer", - /* LWTRANCHE_SUBTRANS_BUFFER: */ - "SubtransBuffer", - /* LWTRANCHE_MULTIXACTOFFSET_BUFFER: */ - "MultiXactOffsetBuffer", - /* LWTRANCHE_MULTIXACTMEMBER_BUFFER: */ - "MultiXactMemberBuffer", - /* LWTRANCHE_NOTIFY_BUFFER: */ - "NotifyBuffer", - /* LWTRANCHE_SERIAL_BUFFER: */ - "SerialBuffer", - /* LWTRANCHE_WAL_INSERT: */ - "WALInsert", - /* LWTRANCHE_BUFFER_CONTENT: */ - "BufferContent", - /* LWTRANCHE_REPLICATION_ORIGIN_STATE: */ - "ReplicationOriginState", - /* LWTRANCHE_REPLICATION_SLOT_IO: */ - "ReplicationSlotIO", - /* LWTRANCHE_LOCK_FASTPATH: */ - "LockFastPath", - /* LWTRANCHE_BUFFER_MAPPING: */ - "BufferMapping", - /* LWTRANCHE_LOCK_MANAGER: */ - "LockManager", - /* LWTRANCHE_PREDICATE_LOCK_MANAGER: */ - "PredicateLockManager", - /* LWTRANCHE_PARALLEL_HASH_JOIN: */ - "ParallelHashJoin", - /* LWTRANCHE_PARALLEL_QUERY_DSA: */ - "ParallelQueryDSA", - /* LWTRANCHE_PER_SESSION_DSA: */ - "PerSessionDSA", - /* LWTRANCHE_PER_SESSION_RECORD_TYPE: */ - "PerSessionRecordType", - /* LWTRANCHE_PER_SESSION_RECORD_TYPMOD: */ - "PerSessionRecordTypmod", - /* LWTRANCHE_SHARED_TUPLESTORE: */ - "SharedTupleStore", - /* LWTRANCHE_SHARED_TIDBITMAP: */ - "SharedTidBitmap", - /* LWTRANCHE_PARALLEL_APPEND: */ - "ParallelAppend", - /* LWTRANCHE_PER_XACT_PREDICATE_LIST: */ - "PerXactPredicateList", - /* LWTRANCHE_PGSTATS_DSA: */ - "PgStatsDSA", - /* LWTRANCHE_PGSTATS_HASH: */ - "PgStatsHash", - /* LWTRANCHE_PGSTATS_DATA: */ - "PgStatsData", - /* LWTRANCHE_LAUNCHER_DSA: */ - "LogicalRepLauncherDSA", - /* LWTRANCHE_LAUNCHER_HASH: */ - "LogicalRepLauncherHash", - /* LWTRANCHE_DSM_REGISTRY_DSA: */ - "DSMRegistryDSA", - /* LWTRANCHE_DSM_REGISTRY_HASH: */ - "DSMRegistryHash", + [LWTRANCHE_XACT_BUFFER] = "XactBuffer", + [LWTRANCHE_COMMITTS_BUFFER] = "CommitTsBuffer", + [LWTRANCHE_SUBTRANS_BUFFER] = "SubtransBuffer", + [LWTRANCHE_MULTIXACTOFFSET_BUFFER] = "MultiXactOffsetBuffer", + [LWTRANCHE_MULTIXACTMEMBER_BUFFER] = "MultiXactMemberBuffer", + [LWTRANCHE_NOTIFY_BUFFER] = "NotifyBuffer", + [LWTRANCHE_SERIAL_BUFFER] = "SerialBuffer", + [LWTRANCHE_WAL_INSERT] = "WALInsert", + [LWTRANCHE_BUFFER_CONTENT] = "BufferContent", + [LWTRANCHE_REPLICATION_ORIGIN_STATE] = "ReplicationOriginState", + [LWTRANCHE_REPLICATION_SLOT_IO] = "ReplicationSlotIO", + [LWTRANCHE_LOCK_FASTPATH] = "LockFastPath", + [LWTRANCHE_BUFFER_MAPPING] = "BufferMapping", + [LWTRANCHE_LOCK_MANAGER] = "LockManager", + [LWTRANCHE_PREDICATE_LOCK_MANAGER] = "PredicateLockManager", + [LWTRANCHE_PARALLEL_HASH_JOIN] = "ParallelHashJoin", + [LWTRANCHE_PARALLEL_QUERY_DSA] = "ParallelQueryDSA", + [LWTRANCHE_PER_SESSION_DSA] = "PerSessionDSA", + [LWTRANCHE_PER_SESSION_RECORD_TYPE] = "PerSessionRecordType", + [LWTRANCHE_PER_SESSION_RECORD_TYPMOD] = "PerSessionRecordTypmod", + [LWTRANCHE_SHARED_TUPLESTORE] = "SharedTupleStore", + [LWTRANCHE_SHARED_TIDBITMAP] = "SharedTidBitmap", + [LWTRANCHE_PARALLEL_APPEND] = "ParallelAppend", + [LWTRANCHE_PER_XACT_PREDICATE_LIST] = "PerXactPredicateList", + [LWTRANCHE_PGSTATS_DSA] = "PgStatsDSA", + [LWTRANCHE_PGSTATS_HASH] = "PgStatsHash", + [LWTRANCHE_PGSTATS_DATA] = "PgStatsData", + [LWTRANCHE_LAUNCHER_DSA] = "LogicalRepLauncherDSA", + [LWTRANCHE_LAUNCHER_HASH] = "LogicalRepLauncherHash", + [LWTRANCHE_DSM_REGISTRY_DSA] = "DSMRegistryDSA", + [LWTRANCHE_DSM_REGISTRY_HASH] = "DSMRegistryHash", }; StaticAssertDecl(lengthof(BuiltinTrancheNames) == - LWTRANCHE_FIRST_USER_DEFINED - NUM_INDIVIDUAL_LWLOCKS, + LWTRANCHE_FIRST_USER_DEFINED, "missing entries in BuiltinTrancheNames[]"); /* @@ -775,7 +744,7 @@ GetLWTrancheName(uint16 trancheId) /* Built-in tranche? */ if (trancheId < LWTRANCHE_FIRST_USER_DEFINED) - return BuiltinTrancheNames[trancheId - NUM_INDIVIDUAL_LWLOCKS]; + return BuiltinTrancheNames[trancheId]; /* * It's an extension tranche, so look in LWLockTrancheNames[]. However, -- 2.39.2