1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/*-------------------------------------------------------------------------
*
* proc.h--
*
*
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: proc.h,v 1.1.1.1 1996/07/09 06:21:53 scrappy Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef _PROC_H_
#define _PROC_H_
#include "storage/ipc.h"
#include "storage/lock.h"
#ifndef WIN32
#include <sys/sem.h>
#else
/* This is because WIN32 already defines PROC */
#define PROC PGL_PROC
#endif /* WIN32 */
#include "storage/shmem.h"
typedef struct {
int sleeplock;
int semNum;
IpcSemaphoreId semId;
IpcSemaphoreKey semKey;
} SEMA;
/*
* Each backend has:
*/
typedef struct proc {
/* proc->links MUST BE THE FIRST ELEMENT OF STRUCT (see ProcWakeup()) */
SHM_QUEUE links; /* proc can be waiting for one event(lock) */
SEMA sem; /* ONE semaphore to sleep on */
int errType; /* error code tells why we woke up */
int procId; /* unique number for this structure
* NOT unique per backend, these things
* are reused after the backend dies.
*/
int critSects; /* If critSects > 0, we are in sensitive
* routines that cannot be recovered when
* the process fails.
*/
int prio; /* priority for sleep queue */
TransactionId xid; /* transaction currently being executed
* by this proc
*/
LOCK * waitLock; /* Lock we're sleeping on */
int token; /* info for proc wakeup routines */
int pid; /* This procs process id */
short sLocks[MAX_SPINS]; /* Spin lock stats */
SHM_QUEUE lockQueue; /* locks associated with current transaction */
} PROC;
/*
* MAX_PROC_SEMS is the maximum number of per-process semaphores (those used
* by the lock mgr) we can keep track of. PROC_NSEMS_PER_SET is the number
* of semaphores in each (sys-V) semaphore set allocated. (Be careful not
* to set it to greater 32. Otherwise, the bitmap will overflow.)
*/
#define MAX_PROC_SEMS 128
#define PROC_NSEMS_PER_SET 16
typedef struct procglobal {
SHMEM_OFFSET freeProcs;
int numProcs;
IPCKey currKey;
int32 freeSemMap[MAX_PROC_SEMS/PROC_NSEMS_PER_SET];
} PROC_HDR;
extern PROC *MyProc;
#define PROC_INCR_SLOCK(lock) if (MyProc) (MyProc->sLocks[(lock)])++
#define PROC_DECR_SLOCK(lock) if (MyProc) (MyProc->sLocks[(lock)])--
/*
* flags explaining why process woke up
*/
#define NO_ERROR 0
#define ERR_TIMEOUT 1
#define ERR_BUFFER_IO 2
#define MAX_PRIO 50
#define MIN_PRIO (-1)
extern SPINLOCK ProcStructLock;
/*
* Function Prototypes
*/
extern void InitProcess(IPCKey key);
extern void ProcReleaseLocks(void);
extern bool ProcRemove(int pid);
/* extern bool ProcKill(int exitStatus, int pid); */
/* make static in storage/lmgr/proc.c -- jolly */
extern PROC_QUEUE *ProcQueueAlloc(char *name);
extern void ProcQueueInit(PROC_QUEUE *queue);
extern int ProcSleep(PROC_QUEUE *queue, SPINLOCK spinlock, int token,
int prio, LOCK *lock);
extern PROC *ProcWakeup(PROC *proc, int errType);
extern int ProcGetId(void);
extern int ProcLockWakeup(PROC_QUEUE *queue, char * ltable, char * lock);
extern void ProcAddLock(SHM_QUEUE *elem);
#if defined(PORTNAME_linux)
extern int HandleDeadLock(int);
#else
extern int HandleDeadLock(void);
#endif
extern void ProcReleaseSpins(PROC *proc);
extern void ProcFreeAllSemaphores(void);
#endif /* PROC_H */
|
