diff options
Diffstat (limited to 'src/include/storage/proc.h')
| -rw-r--r-- | src/include/storage/proc.h | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h index 65308d71ada..1007013a9df 100644 --- a/src/include/storage/proc.h +++ b/src/include/storage/proc.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2000, PostgreSQL, Inc * Portions Copyright (c) 1994, Regents of the University of California * - * $Id: proc.h,v 1.34 2001/01/14 05:08:16 tgl Exp $ + * $Id: proc.h,v 1.35 2001/01/16 06:11:34 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -27,13 +27,20 @@ typedef struct } SEMA; /* - * Each backend has: + * Each backend has a PROC struct in shared memory. There is also a list + * of currently-unused PROC structs that will be reallocated to new backends + * (a fairly pointless optimization, but it's there anyway). + * + * links: list link for any list the PROC is in. When waiting for a lock, + * the PROC is linked into that lock's waitProcs queue. A recycled PROC + * is linked into ProcGlobal's freeProcs list. */ struct proc { /* proc->links MUST BE THE FIRST ELEMENT OF STRUCT (see ProcWakeup()) */ - SHM_QUEUE links; /* proc can be waiting for one event(lock) */ + SHM_QUEUE links; /* list link if process is in a list */ + SEMA sem; /* ONE semaphore to sleep on */ int errType; /* error code tells why we woke up */ @@ -48,16 +55,17 @@ struct proc /* Info about lock the process is currently waiting for, if any */ LOCK *waitLock; /* Lock object we're sleeping on ... */ - HOLDER *waitHolder; /* Per-holder info for our lock */ + HOLDER *waitHolder; /* Per-holder info for awaited lock */ LOCKMODE waitLockMode; /* type of lock we're waiting for */ - LOCKMASK holdLock; /* bitmask for lock types already held */ + LOCKMASK heldLocks; /* bitmask for lock types already held on + * this lock object by this backend */ int pid; /* This backend's process id */ Oid databaseId; /* OID of database this backend is using */ short sLocks[MAX_SPINS]; /* Spin lock stats */ - SHM_QUEUE lockQueue; /* locks associated with current - * transaction */ + SHM_QUEUE holderQueue; /* list of HOLDER objects for locks held or + * awaited by this backend */ }; /* NOTE: "typedef struct proc PROC" appears in storage/lock.h. */ |