Drop the redundant "Lock" suffix from LWLock wait event names.

This was mostly confusing, especially since some wait events in
this class had the suffix and some did not.

While at it, stop exposing MainLWLockNames[] as a globally visible
name; any code using that directly is almost certainly wrong, as
its name has been misleading for some time.
(GetLWLockIdentifier() is what to use instead.)

Discussion: https://postgr.es/m/28683.1589405363@sss.pgh.pa.us

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index e5b21cd8f61f9c05ce4e512f737e96cb41be44e8..42755659e1b3a712d3754feb43f072509fb48c87 100644 (file)
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -1750,31 +1750,31 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
 
     <tbody>
      <row>
-      <entry><literal>AddinShmemInitLock</literal></entry>
+      <entry><literal>AddinShmemInit</literal></entry>
       <entry>Waiting to manage an extension's space allocation in shared
        memory.</entry>
      </row>
      <row>
-      <entry><literal>AutoFileLock</literal></entry>
+      <entry><literal>AutoFile</literal></entry>
       <entry>Waiting to update the <filename>postgresql.auto.conf</filename>
        file.</entry>
      </row>
      <row>
-      <entry><literal>AutovacuumLock</literal></entry>
+      <entry><literal>Autovacuum</literal></entry>
       <entry>Waiting to read or update the current state of autovacuum
        workers.</entry>
      </row>
      <row>
-      <entry><literal>AutovacuumScheduleLock</literal></entry>
+      <entry><literal>AutovacuumSchedule</literal></entry>
       <entry>Waiting to ensure that a table selected for autovacuum
        still needs vacuuming.</entry>
      </row>
      <row>
-      <entry><literal>BackgroundWorkerLock</literal></entry>
+      <entry><literal>BackgroundWorker</literal></entry>
       <entry>Waiting to read or update background worker state.</entry>
      </row>
      <row>
-      <entry><literal>BtreeVacuumLock</literal></entry>
+      <entry><literal>BtreeVacuum</literal></entry>
       <entry>Waiting to read or update vacuum-related information for a
        B-tree index.</entry>
      </row>
@@ -1792,15 +1792,15 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        pool.</entry>
      </row>
      <row>
-      <entry><literal>CheckpointLock</literal></entry>
+      <entry><literal>Checkpoint</literal></entry>
       <entry>Waiting to begin a checkpoint.</entry>
      </row>
      <row>
-      <entry><literal>CheckpointerCommLock</literal></entry>
+      <entry><literal>CheckpointerComm</literal></entry>
       <entry>Waiting to manage fsync requests.</entry>
      </row>
      <row>
-      <entry><literal>CommitTsLock</literal></entry>
+      <entry><literal>CommitTs</literal></entry>
       <entry>Waiting to read or update the last value set for a
        transaction commit timestamp.</entry>
      </row>
@@ -1809,16 +1809,16 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       <entry>Waiting for I/O on a commit timestamp SLRU buffer.</entry>
      </row>
      <row>
-      <entry><literal>CommitTsSLRULock</literal></entry>
+      <entry><literal>CommitTsSLRU</literal></entry>
       <entry>Waiting to access the commit timestamp SLRU cache.</entry>
      </row>
      <row>
-      <entry><literal>ControlFileLock</literal></entry>
+      <entry><literal>ControlFile</literal></entry>
       <entry>Waiting to read or update the <filename>pg_control</filename>
        file or create a new WAL file.</entry>
      </row>
      <row>
-      <entry><literal>DynamicSharedMemoryControlLock</literal></entry>
+      <entry><literal>DynamicSharedMemoryControl</literal></entry>
       <entry>Waiting to read or update dynamic shared memory allocation
        information.</entry>
      </row>
@@ -1833,12 +1833,12 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        about <quote>heavyweight</quote> locks.</entry>
      </row>
      <row>
-      <entry><literal>LogicalRepWorkerLock</literal></entry>
+      <entry><literal>LogicalRepWorker</literal></entry>
       <entry>Waiting to read or update the state of logical replication
        workers.</entry>
      </row>
      <row>
-      <entry><literal>MultiXactGenLock</literal></entry>
+      <entry><literal>MultiXactGen</literal></entry>
       <entry>Waiting to read or update shared multixact state.</entry>
      </row>
      <row>
@@ -1846,7 +1846,7 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       <entry>Waiting for I/O on a multixact member SLRU buffer.</entry>
      </row>
      <row>
-      <entry><literal>MultiXactMemberSLRULock</literal></entry>
+      <entry><literal>MultiXactMemberSLRU</literal></entry>
       <entry>Waiting to access the multixact member SLRU cache.</entry>
      </row>
      <row>
@@ -1854,11 +1854,11 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       <entry>Waiting for I/O on a multixact offset SLRU buffer.</entry>
      </row>
      <row>
-      <entry><literal>MultiXactOffsetSLRULock</literal></entry>
+      <entry><literal>MultiXactOffsetSLRU</literal></entry>
       <entry>Waiting to access the multixact offset SLRU cache.</entry>
      </row>
      <row>
-      <entry><literal>MultiXactTruncationLock</literal></entry>
+      <entry><literal>MultiXactTruncation</literal></entry>
       <entry>Waiting to read or truncate multixact information.</entry>
      </row>
      <row>
@@ -1867,20 +1867,20 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        buffer.</entry>
      </row>
      <row>
-      <entry><literal>NotifyQueueLock</literal></entry>
+      <entry><literal>NotifyQueue</literal></entry>
       <entry>Waiting to read or update <command>NOTIFY</command> messages.</entry>
      </row>
      <row>
-      <entry><literal>NotifySLRULock</literal></entry>
+      <entry><literal>NotifySLRU</literal></entry>
       <entry>Waiting to access the <command>NOTIFY</command> message SLRU
        cache.</entry>
      </row>
      <row>
-      <entry><literal>OidGenLock</literal></entry>
+      <entry><literal>OidGen</literal></entry>
       <entry>Waiting to allocate a new OID.</entry>
      </row>
      <row>
-      <entry><literal>OldSnapshotTimeMapLock</literal></entry>
+      <entry><literal>OldSnapshotTimeMap</literal></entry>
       <entry>Waiting to read or update old snapshot control information.</entry>
      </row>
      <row>
@@ -1922,24 +1922,24 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        serializable transactions.</entry>
      </row>
      <row>
-      <entry><literal>ProcArrayLock</literal></entry>
+      <entry><literal>ProcArray</literal></entry>
       <entry>Waiting to access the shared per-process data structures
        (typically, to get a snapshot or report a session's transaction
        ID).</entry>
      </row>
      <row>
-      <entry><literal>RelationMappingLock</literal></entry>
+      <entry><literal>RelationMapping</literal></entry>
       <entry>Waiting to read or update
        a <filename>pg_filenode.map</filename> file (used to track the
        filenode assignments of certain system catalogs).</entry>
      </row>
      <row>
-      <entry><literal>RelCacheInitLock</literal></entry>
+      <entry><literal>RelCacheInit</literal></entry>
       <entry>Waiting to read or update a <filename>pg_internal.init</filename>
        relation cache initialization file.</entry>
      </row>
      <row>
-      <entry><literal>ReplicationOriginLock</literal></entry>
+      <entry><literal>ReplicationOrigin</literal></entry>
       <entry>Waiting to create, drop or use a replication origin.</entry>
      </row>
      <row>
@@ -1948,11 +1948,11 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        origin.</entry>
      </row>
      <row>
-      <entry><literal>ReplicationSlotAllocationLock</literal></entry>
+      <entry><literal>ReplicationSlotAllocation</literal></entry>
       <entry>Waiting to allocate or free a replication slot.</entry>
      </row>
      <row>
-      <entry><literal>ReplicationSlotControlLock</literal></entry>
+      <entry><literal>ReplicationSlotControl</literal></entry>
       <entry>Waiting to read or update replication slot state.</entry>
      </row>
      <row>
@@ -1965,22 +1965,22 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        buffer.</entry>
      </row>
      <row>
-      <entry><literal>SerializableFinishedListLock</literal></entry>
+      <entry><literal>SerializableFinishedList</literal></entry>
       <entry>Waiting to access the list of finished serializable
        transactions.</entry>
      </row>
      <row>
-      <entry><literal>SerializablePredicateListLock</literal></entry>
+      <entry><literal>SerializablePredicateList</literal></entry>
       <entry>Waiting to access the list of predicate locks held by
        serializable transactions.</entry>
      </row>
      <row>
-      <entry><literal>SerializableXactHashLock</literal></entry>
+      <entry><literal>SerializableXactHash</literal></entry>
       <entry>Waiting to read or update information about serializable
        transactions.</entry>
      </row>
      <row>
-      <entry><literal>SerialSLRULock</literal></entry>
+      <entry><literal>SerialSLRU</literal></entry>
       <entry>Waiting to access the serializable transaction conflict SLRU
        cache.</entry>
      </row>
@@ -1995,16 +1995,16 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        query.</entry>
      </row>
      <row>
-      <entry><literal>ShmemIndexLock</literal></entry>
+      <entry><literal>ShmemIndex</literal></entry>
       <entry>Waiting to find or allocate space in shared memory.</entry>
      </row>
      <row>
-      <entry><literal>SInvalReadLock</literal></entry>
+      <entry><literal>SInvalRead</literal></entry>
       <entry>Waiting to retrieve messages from the shared catalog invalidation
        queue.</entry>
      </row>
      <row>
-      <entry><literal>SInvalWriteLock</literal></entry>
+      <entry><literal>SInvalWrite</literal></entry>
       <entry>Waiting to add a message to the shared catalog invalidation
       queue.</entry>
      </row>
@@ -2013,29 +2013,29 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       <entry>Waiting for I/O on a sub-transaction SLRU buffer.</entry>
      </row>
      <row>
-      <entry><literal>SubtransSLRULock</literal></entry>
+      <entry><literal>SubtransSLRU</literal></entry>
       <entry>Waiting to access the sub-transaction SLRU cache.</entry>
      </row>
      <row>
-      <entry><literal>SyncRepLock</literal></entry>
+      <entry><literal>SyncRep</literal></entry>
       <entry>Waiting to read or update information about the state of
        synchronous replication.</entry>
      </row>
      <row>
-      <entry><literal>SyncScanLock</literal></entry>
+      <entry><literal>SyncScan</literal></entry>
       <entry>Waiting to select the starting location of a synchronized table
        scan.</entry>
      </row>
      <row>
-      <entry><literal>TablespaceCreateLock</literal></entry>
+      <entry><literal>TablespaceCreate</literal></entry>
       <entry>Waiting to create or drop a tablespace.</entry>
      </row>
      <row>
-      <entry><literal>TwoPhaseStateLock</literal></entry>
+      <entry><literal>TwoPhaseState</literal></entry>
       <entry>Waiting to read or update the state of prepared transactions.</entry>
      </row>
      <row>
-      <entry><literal>WALBufMappingLock</literal></entry>
+      <entry><literal>WALBufMapping</literal></entry>
       <entry>Waiting to replace a page in WAL buffers.</entry>
      </row>
      <row>
@@ -2043,7 +2043,7 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       <entry>Waiting to insert WAL data into a memory buffer.</entry>
      </row>
      <row>
-      <entry><literal>WALWriteLock</literal></entry>
+      <entry><literal>WALWrite</literal></entry>
       <entry>Waiting for WAL buffers to be written to disk.</entry>
      </row>
      <row>
@@ -2051,16 +2051,16 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       <entry>Waiting for I/O on a transaction status SLRU buffer.</entry>
      </row>
      <row>
-      <entry><literal>XactSLRULock</literal></entry>
+      <entry><literal>XactSLRU</literal></entry>
       <entry>Waiting to access the transaction status SLRU cache.</entry>
      </row>
      <row>
-      <entry><literal>XactTruncationLock</literal></entry>
+      <entry><literal>XactTruncation</literal></entry>
       <entry>Waiting to execute <function>pg_xact_status</function> or update
        the oldest transaction ID available to it.</entry>
      </row>
      <row>
-      <entry><literal>XidGenLock</literal></entry>
+      <entry><literal>XidGen</literal></entry>
       <entry>Waiting to allocate a new transaction ID.</entry>
      </row>
     </tbody>

diff --git a/src/backend/storage/lmgr/generate-lwlocknames.pl b/src/backend/storage/lmgr/generate-lwlocknames.pl
index 50fb8625cad9a1304064c983f53c9fedb0f55d5e..ca54acdfb0f88b8cbc18d070481a0e6adb94dbe9 100644 (file)
--- a/src/backend/storage/lmgr/generate-lwlocknames.pl
+++ b/src/backend/storage/lmgr/generate-lwlocknames.pl
@@ -23,7 +23,7 @@ print $h $autogen;
 print $h "/* there is deliberately not an #ifndef LWLOCKNAMES_H here */\n\n";
 print $c $autogen, "\n";
 
-print $c "const char *const MainLWLockNames[] = {";
+print $c "const char *const IndividualLWLockNames[] = {";
 
 while (<$lwlocknames>)
 {
@@ -38,6 +38,10 @@ while (<$lwlocknames>)
 
        (my $lockname, my $lockidx) = ($1, $2);
 
+       my $trimmedlockname = $lockname;
+       $trimmedlockname =~ s/Lock$//;
+       die "lock names must end with 'Lock'" if $trimmedlockname eq $lockname;
+
        die "lwlocknames.txt not in order"   if $lockidx < $lastlockidx;
        die "lwlocknames.txt has duplicates" if $lockidx == $lastlockidx;
 
@@ -47,7 +51,7 @@ while (<$lwlocknames>)
                printf $c "%s   \"<unassigned:%d>\"", $continue, $lastlockidx;
                $continue = ",\n";
        }
-       printf $c "%s   \"%s\"", $continue, $lockname;
+       printf $c "%s   \"%s\"", $continue, $trimmedlockname;
        $lastlockidx = $lockidx;
        $continue    = ",\n";
 

diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 0bdc8e0499da33b416bd24d26efd8987d89d8de9..2fa90cc0954d9e58f311c18d0e7e402ec900f16e 100644 (file)
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -111,7 +111,7 @@ extern slock_t *ShmemLock;
  * There are three sorts of LWLock "tranches":
  *
  * 1. The individually-named locks defined in lwlocknames.h each have their
- * own tranche.  The names of these tranches appear in MainLWLockNames[]
+ * own tranche.  The names of these tranches appear in IndividualLWLockNames[]
  * in lwlocknames.c.
  *
  * 2. There are some predefined tranches for built-in groups of locks.
@@ -125,6 +125,7 @@ extern slock_t *ShmemLock;
  * All these names are user-visible as wait event names, so choose with care
  * ... and do not forget to update the documentation's list of wait events.
  */
+extern const char *const IndividualLWLockNames[];      /* in lwlocknames.c */
 
 static const char *const BuiltinTrancheNames[] = {
        /* LWTRANCHE_XACT_BUFFER: */
@@ -781,7 +782,7 @@ GetLWTrancheName(uint16 trancheId)
 {
        /* Individual LWLock? */
        if (trancheId < NUM_INDIVIDUAL_LWLOCKS)
-               return MainLWLockNames[trancheId];
+               return IndividualLWLockNames[trancheId];
 
        /* Built-in tranche? */
        if (trancheId < LWTRANCHE_FIRST_USER_DEFINED)

diff --git a/src/include/storage/lwlock.h b/src/include/storage/lwlock.h
index d8e1b5c493eb707a0910503c18e0e5249fe7eec3..c04ae971485e311c741c6332232382e39573422f 100644 (file)
--- a/src/include/storage/lwlock.h
+++ b/src/include/storage/lwlock.h
@@ -88,7 +88,6 @@ typedef union LWLockMinimallyPadded
 } LWLockMinimallyPadded;
 
 extern PGDLLIMPORT LWLockPadded *MainLWLockArray;
-extern const char *const MainLWLockNames[];
 
 /* struct for storing named tranche information */
 typedef struct NamedLWLockTranche