Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit2c6d96c

Browse files
committed
Add support for loadable modules to allocated shared memory and
lightweight locks.Marc Munro
1 parentc61607b commit2c6d96c

File tree

6 files changed

+261
-13
lines changed

6 files changed

+261
-13
lines changed

‎src/backend/storage/ipc/ipci.c‎

Lines changed: 21 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.86 2006/07/15 15:47:17 tgl Exp $
11+
* $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.87 2006/08/01 19:03:11 momjian Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -57,6 +57,7 @@ CreateSharedMemoryAndSemaphores(bool makePrivate, int port)
5757
{
5858
PGShmemHeader*seghdr;
5959
Sizesize;
60+
Sizesize_b4addins;
6061
intnumSemas;
6162

6263
/*
@@ -93,6 +94,15 @@ CreateSharedMemoryAndSemaphores(bool makePrivate, int port)
9394
/* might as well round it off to a multiple of a typical page size */
9495
size=add_size(size,8192- (size %8192));
9596

97+
/*
98+
* The shared memory for add-ins is treated as a separate
99+
* segment, but in reality it is not.
100+
*/
101+
size_b4addins=size;
102+
size=add_size(size,AddinShmemSize());
103+
/* round it off again */
104+
size=add_size(size,8192- (size %8192));
105+
96106
elog(DEBUG3,"invoking IpcMemoryCreate(size=%lu)",
97107
(unsigned long)size);
98108

@@ -101,6 +111,16 @@ CreateSharedMemoryAndSemaphores(bool makePrivate, int port)
101111
*/
102112
seghdr=PGSharedMemoryCreate(size,makePrivate,port);
103113

114+
/*
115+
* Modify hdr to show segment size before add-ins
116+
*/
117+
seghdr->totalsize=size_b4addins;
118+
119+
/*
120+
* Set up segment header sections in each Addin context
121+
*/
122+
InitAddinContexts((void*) ((char*)seghdr+size_b4addins));
123+
104124
InitShmemAccess(seghdr);
105125

106126
/*

‎src/backend/storage/ipc/shmem.c‎

Lines changed: 153 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/storage/ipc/shmem.c,v 1.94 2006/07/22 23:04:39 tgl Exp $
11+
* $PostgreSQL: pgsql/src/backend/storage/ipc/shmem.c,v 1.95 2006/08/01 19:03:11 momjian Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -61,6 +61,15 @@
6161
*cannot be redistributed to other tables. We could build a simple
6262
*hash bucket garbage collector if need be. Right now, it seems
6363
*unnecessary.
64+
*
65+
* (e) Add-ins can request their own logical shared memory segments
66+
* by calling RegisterAddinContext() from the preload-libraries hook.
67+
* Each call establishes a uniquely named add-in shared memopry
68+
* context which will be set up as part of postgres intialisation.
69+
* Memory can be allocated from these contexts using
70+
* ShmemAllocFromContext(), and can be reset to its initial condition
71+
* using ShmemResetContext(). Also, RegisterAddinLWLock(LWLockid *lock_ptr)
72+
* can be used to request that a LWLock be allocated, placed into *lock_ptr.
6473
*/
6574

6675
#include"postgres.h"
@@ -86,6 +95,19 @@ slock_t *ShmemLock;/* spinlock for shared memory and LWLock
8695

8796
staticHTAB*ShmemIndex=NULL;/* primary index hashtable for shmem */
8897

98+
/* Structures and globals for managing add-in shared memory contexts */
99+
typedefstructcontext
100+
{
101+
char*name;
102+
Sizesize;
103+
PGShmemHeader*seg_hdr;
104+
structcontext*next;
105+
}ContextNode;
106+
107+
staticContextNode*addin_contexts=NULL;
108+
staticSizeaddin_contexts_size=0;
109+
110+
89111

90112
/*
91113
*InitShmemAccess() --- set up basic pointers to shared memory.
@@ -135,12 +157,104 @@ InitShmemAllocation(void)
135157
* (This doesn't really belong here, but not worth moving.)
136158
*/
137159
ShmemVariableCache= (VariableCache)
138-
ShmemAlloc(sizeof(*ShmemVariableCache));
160+
ShmemAlloc(sizeof(*ShmemVariableCache));
139161
memset(ShmemVariableCache,0,sizeof(*ShmemVariableCache));
140162
}
141163

142164
/*
143-
* ShmemAlloc -- allocate max-aligned chunk from shared memory
165+
* RegisterAddinContext -- Register the requirement for a named shared
166+
* memory context.
167+
*/
168+
void
169+
RegisterAddinContext(constchar*name,Sizesize)
170+
{
171+
char*newstr=malloc(strlen(name)+1);
172+
ContextNode*node=malloc(sizeof(ContextNode));
173+
174+
strcpy(newstr,name);
175+
node->name=newstr;
176+
177+
/* Round up to typical page size */
178+
node->size=add_size(size,8192- (size %8192));
179+
node->next=addin_contexts;
180+
181+
addin_contexts=node;
182+
addin_contexts_size=add_size(addin_contexts_size,node->size);
183+
}
184+
185+
186+
/*
187+
* ContextFromName -- Return the ContextNode for the given named
188+
* context, or NULL if not found.
189+
*/
190+
staticContextNode*
191+
ContextFromName(constchar*name)
192+
{
193+
ContextNode*context=addin_contexts;
194+
195+
while (context)
196+
{
197+
if (strcmp(name,context->name)==0)
198+
returncontext;
199+
context=context->next;
200+
}
201+
returnNULL;
202+
}
203+
204+
/*
205+
* InitAddinContexts -- Initialise the registered addin shared memory
206+
* contexts.
207+
*/
208+
void
209+
InitAddinContexts(void*start)
210+
{
211+
PGShmemHeader*next_segment= (PGShmemHeader*)start;
212+
ContextNode*context=addin_contexts;
213+
214+
while (context)
215+
{
216+
context->seg_hdr=next_segment;
217+
218+
next_segment->totalsize=context->size;
219+
next_segment->freeoffset=MAXALIGN(sizeof(PGShmemHeader));
220+
221+
next_segment= (PGShmemHeader*)
222+
((char*)next_segment+context->size);
223+
context=context->next;
224+
}
225+
}
226+
227+
/*
228+
* ShmemResetContext -- Re-initialise the named addin shared memory context.
229+
*/
230+
void
231+
ShmemResetContext(constchar*name)
232+
{
233+
PGShmemHeader*segment;
234+
ContextNode*context=ContextFromName(name);
235+
236+
if (!context)
237+
ereport(ERROR,
238+
(errcode(ERRCODE_INTERNAL_ERROR),
239+
errmsg("cannot reset unknown shared memory context %s",
240+
name)));
241+
242+
segment=context->seg_hdr;
243+
segment->freeoffset=MAXALIGN(sizeof(PGShmemHeader));
244+
}
245+
246+
/*
247+
* AddinShmemSize -- Report how much shared memory has been registered
248+
* for add-ins.
249+
*/
250+
Size
251+
AddinShmemSize(void)
252+
{
253+
returnaddin_contexts_size;
254+
}
255+
256+
/*
257+
* ShmemAllocFromContext -- allocate max-aligned chunk from shared memory
144258
*
145259
* Assumes ShmemLock and ShmemSegHdr are initialized.
146260
*
@@ -149,15 +263,30 @@ InitShmemAllocation(void)
149263
*to be compatible with malloc().
150264
*/
151265
void*
152-
ShmemAlloc(Sizesize)
266+
ShmemAllocFromContext(Sizesize,constchar*context_name)
153267
{
154-
SizenewStart;
155-
SizenewFree;
156-
void*newSpace;
268+
SizenewStart;
269+
SizenewFree;
270+
void*newSpace;
271+
ContextNode*context;
157272

158273
/* use volatile pointer to prevent code rearrangement */
159274
volatilePGShmemHeader*shmemseghdr=ShmemSegHdr;
160275

276+
/*
277+
* if context_name is provided, allocate from the named context
278+
*/
279+
if (context_name)
280+
{
281+
context=ContextFromName(context_name);
282+
if (!context)
283+
ereport(ERROR,
284+
(errcode(ERRCODE_INTERNAL_ERROR),
285+
errmsg("cannot reset unknown shared memory context %s",
286+
context_name)));
287+
shmemseghdr=context->seg_hdr;
288+
}
289+
161290
/*
162291
* ensure all space is adequately aligned.
163292
*/
@@ -176,7 +305,7 @@ ShmemAlloc(Size size)
176305
newFree=newStart+size;
177306
if (newFree <=shmemseghdr->totalsize)
178307
{
179-
newSpace= (void*)MAKE_PTR(newStart);
308+
newSpace= (void*)MAKE_PTRFROM((SHMEM_OFFSET)shmemseghdr,newStart);
180309
shmemseghdr->freeoffset=newFree;
181310
}
182311
else
@@ -192,6 +321,22 @@ ShmemAlloc(Size size)
192321
returnnewSpace;
193322
}
194323

324+
/*
325+
* ShmemAlloc -- allocate max-aligned chunk from shared memory
326+
*
327+
* Assumes ShmemLock and ShmemSegHdr are initialized.
328+
*
329+
* Returns: real pointer to memory or NULL if we are out
330+
*of space. Has to return a real pointer in order
331+
*to be compatible with malloc().
332+
*/
333+
334+
void*
335+
ShmemAlloc(Sizesize)
336+
{
337+
returnShmemAllocFromContext(size,NULL);
338+
}
339+
195340
/*
196341
* ShmemIsValid -- test if an offset refers to valid shared memory
197342
*

‎src/backend/storage/lmgr/lwlock.c‎

Lines changed: 70 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -15,7 +15,7 @@
1515
* Portions Copyright (c) 1994, Regents of the University of California
1616
*
1717
* IDENTIFICATION
18-
* $PostgreSQL: pgsql/src/backend/storage/lmgr/lwlock.c,v 1.42 2006/07/24 16:32:45 petere Exp $
18+
* $PostgreSQL: pgsql/src/backend/storage/lmgr/lwlock.c,v 1.43 2006/08/01 19:03:11 momjian Exp $
1919
*
2020
*-------------------------------------------------------------------------
2121
*/
@@ -29,6 +29,10 @@
2929
#include"storage/spin.h"
3030

3131

32+
staticintNumAddinLWLocks(void);
33+
staticvoidAssignAddinLWLocks(void);
34+
35+
3236
/* We use the ShmemLock spinlock to protect LWLockAssign */
3337
externslock_t*ShmemLock;
3438

@@ -90,6 +94,62 @@ static int *ex_acquire_counts;
9094
staticint*block_counts;
9195
#endif
9296

97+
/*
98+
* Structures and globals to allow add-ins to register for their own
99+
* lwlocks from the preload-libraries hook.
100+
*/
101+
typedefstructLWLockNode
102+
{
103+
LWLockId*lock;
104+
structLWLockNode*next;
105+
}LWLockNode;
106+
107+
staticLWLockNode*addin_locks=NULL;
108+
staticintnum_addin_locks=0;
109+
110+
111+
/*
112+
*RegisterAddinLWLock() --- Allow an andd-in to request a LWLock
113+
* from the preload-libraries hook.
114+
*/
115+
void
116+
RegisterAddinLWLock(LWLockId*lock)
117+
{
118+
LWLockNode*locknode=malloc(sizeof(LWLockNode));
119+
120+
locknode->next=addin_locks;
121+
locknode->lock=lock;
122+
123+
addin_locks=locknode;
124+
num_addin_locks++;
125+
}
126+
127+
/*
128+
*NumAddinLWLocks() --- Return the number of LWLocks requested by add-ins.
129+
*/
130+
int
131+
NumAddinLWLocks()
132+
{
133+
returnnum_addin_locks;
134+
}
135+
136+
/*
137+
*AssignAddinLWLocks() --- Assign LWLocks previously requested by add-ins.
138+
*/
139+
void
140+
AssignAddinLWLocks()
141+
{
142+
LWLockNode*node=addin_locks;
143+
144+
while (node)
145+
{
146+
*(node->lock)=LWLockAssign();
147+
node=node->next;
148+
}
149+
}
150+
151+
152+
93153

94154
#ifdefLOCK_DEBUG
95155
boolTrace_lwlocks= false;
@@ -174,6 +234,9 @@ NumLWLocks(void)
174234
/* Leave a few extra for use by user-defined modules. */
175235
numLocks+=NUM_USER_DEFINED_LWLOCKS;
176236

237+
/* Add the number that have been explicitly requested by add-ins. */
238+
numLocks+=NumAddinLWLocks();
239+
177240
returnnumLocks;
178241
}
179242

@@ -241,6 +304,12 @@ CreateLWLocks(void)
241304
LWLockCounter= (int*) ((char*)LWLockArray-2*sizeof(int));
242305
LWLockCounter[0]= (int)NumFixedLWLocks;
243306
LWLockCounter[1]=numLocks;
307+
308+
/*
309+
* Allocate LWLocks for those add-ins that have explicitly requested
310+
* them.
311+
*/
312+
AssignAddinLWLocks();
244313
}
245314

246315

‎src/include/storage/lwlock.h‎

Lines changed: 3 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@
77
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
88
* Portions Copyright (c) 1994, Regents of the University of California
99
*
10-
* $PostgreSQL: pgsql/src/include/storage/lwlock.h,v 1.30 2006/07/23 23:08:46 tgl Exp $
10+
* $PostgreSQL: pgsql/src/include/storage/lwlock.h,v 1.31 2006/08/01 19:03:11 momjian Exp $
1111
*
1212
*-------------------------------------------------------------------------
1313
*/
@@ -92,4 +92,6 @@ extern intNumLWLocks(void);
9292
externSizeLWLockShmemSize(void);
9393
externvoidCreateLWLocks(void);
9494

95+
externvoidRegisterAddinLWLock(LWLockId*lock);
96+
9597
#endif/* LWLOCK_H */

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp