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dsm.h
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1 /*-------------------------------------------------------------------------
2  *
3  * dsm.h
4  * manage dynamic shared memory segments
5  *
6  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  * src/include/storage/dsm.h
10  *
11  *-------------------------------------------------------------------------
12  */
13 #ifndef DSM_H
14 #define DSM_H
15 
16 #include "storage/dsm_impl.h"
17 
18 typedef struct dsm_segment dsm_segment;
19 
20 #define DSM_CREATE_NULL_IF_MAXSEGMENTS 0x0001
21 
22 /* Startup and shutdown functions. */
23 struct PGShmemHeader; /* avoid including pg_shmem.h */
24 extern void dsm_cleanup_using_control_segment(dsm_handle old_control_handle);
25 extern void dsm_postmaster_startup(struct PGShmemHeader *);
26 extern void dsm_backend_shutdown(void);
27 extern void dsm_detach_all(void);
28 
29 extern size_t dsm_estimate_size(void);
30 extern void dsm_shmem_init(void);
31 
32 #ifdef EXEC_BACKEND
33 extern void dsm_set_control_handle(dsm_handle h);
34 #endif
35 
36 /* Functions that create or remove mappings. */
37 extern dsm_segment *dsm_create(Size size, int flags);
39 extern void dsm_detach(dsm_segment *seg);
40 
41 /* Resource management functions. */
42 extern void dsm_pin_mapping(dsm_segment *seg);
43 extern void dsm_unpin_mapping(dsm_segment *seg);
44 extern void dsm_pin_segment(dsm_segment *seg);
45 extern void dsm_unpin_segment(dsm_handle handle);
47 
48 /* Informational functions. */
49 extern void *dsm_segment_address(dsm_segment *seg);
52 
53 /* Cleanup hooks. */
55 extern void on_dsm_detach(dsm_segment *seg,
56  on_dsm_detach_callback function, Datum arg);
57 extern void cancel_on_dsm_detach(dsm_segment *seg,
58  on_dsm_detach_callback function, Datum arg);
59 extern void reset_on_dsm_detach(void);
60 
61 #endif /* DSM_H */
size_t Size
Definition: c.h:592
dsm_handle dsm_segment_handle(dsm_segment *seg)
Definition: dsm.c:1124
size_t dsm_estimate_size(void)
Definition: dsm.c:471
void * dsm_segment_address(dsm_segment *seg)
Definition: dsm.c:1096
void dsm_detach(dsm_segment *seg)
Definition: dsm.c:804
void on_dsm_detach(dsm_segment *seg, on_dsm_detach_callback function, Datum arg)
Definition: dsm.c:1133
dsm_segment * dsm_attach(dsm_handle h)
Definition: dsm.c:666
dsm_segment * dsm_create(Size size, int flags)
Definition: dsm.c:517
void dsm_pin_mapping(dsm_segment *seg)
Definition: dsm.c:916
void dsm_postmaster_startup(struct PGShmemHeader *)
Definition: dsm.c:178
void dsm_unpin_segment(dsm_handle handle)
Definition: dsm.c:989
void dsm_pin_segment(dsm_segment *seg)
Definition: dsm.c:956
void dsm_detach_all(void)
Definition: dsm.c:776
void dsm_cleanup_using_control_segment(dsm_handle old_control_handle)
Definition: dsm.c:239
void(* on_dsm_detach_callback)(dsm_segment *, Datum arg)
Definition: dsm.h:54
void dsm_shmem_init(void)
Definition: dsm.c:480
void dsm_backend_shutdown(void)
Definition: dsm.c:758
void cancel_on_dsm_detach(dsm_segment *seg, on_dsm_detach_callback function, Datum arg)
Definition: dsm.c:1148
void reset_on_dsm_detach(void)
Definition: dsm.c:1171
dsm_segment * dsm_find_mapping(dsm_handle handle)
Definition: dsm.c:1077
Size dsm_segment_map_length(dsm_segment *seg)
Definition: dsm.c:1106
void dsm_unpin_mapping(dsm_segment *seg)
Definition: dsm.c:935
uint32 dsm_handle
Definition: dsm_impl.h:55
void * arg
uintptr_t Datum
Definition: postgres.h:64
static pg_noinline void Size size
Definition: slab.c:607