MBlock.c 6.05 KB
Newer Older
1
/* -----------------------------------------------------------------------------
sof's avatar
sof committed
2
 * $Id: MBlock.c,v 1.28 2002/04/12 04:00:35 sof Exp $
3
4
 *
 * (c) The GHC Team 1998-1999
5
6
7
8
9
10
11
 *
 * MegaBlock Allocator Interface.  This file contains all the dirty
 * architecture-dependent hackery required to get a chunk of aligned
 * memory from the operating system.
 *
 * ---------------------------------------------------------------------------*/

12
13
/* This is non-posix compliant. */
/* #include "PosixSource.h" */
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

#include "Rts.h"
#include "RtsUtils.h"
#include "RtsFlags.h"
#include "MBlock.h"
#include "BlockAlloc.h"

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif

sof's avatar
sof committed
29
30
31
32
#ifndef mingw32_TARGET_OS
# ifdef HAVE_SYS_MMAN_H
# include <sys/mman.h>
# endif
33
34
35
36
37
38
#endif

#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif

sof's avatar
sof committed
39
#if HAVE_WINDOWS_H
40
41
42
#include <windows.h>
#endif

43
44
lnat mblocks_allocated = 0;

45
46
47
48
49
50
void *
getMBlock(void)
{
  return getMBlocks(1);
}

sof's avatar
sof committed
51
#if !defined(mingw32_TARGET_OS) && !defined(cygwin32_TARGET_OS)
52
53
54
void *
getMBlocks(nat n)
{
55
  static caddr_t next_request = (caddr_t)HEAP_BASE;
56
57
58
59
60
61
62
63
64
65
  caddr_t ret;
  lnat size = MBLOCK_SIZE * n;
 
#ifdef solaris2_TARGET_OS
  { 
      int fd = open("/dev/zero",O_RDONLY);
      ret = mmap(next_request, size, PROT_READ | PROT_WRITE, 
		 MAP_FIXED | MAP_PRIVATE, fd, 0);
      close(fd);
  }
66
67
68
#elif hpux_TARGET_OS
 ret = mmap(next_request, size, PROT_READ | PROT_WRITE, 
	     MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
sebc's avatar
sebc committed
69
#elif darwin_TARGET_OS
70
71
 ret = mmap(next_request, size, PROT_READ | PROT_WRITE, 
            MAP_FIXED | MAP_ANON | MAP_PRIVATE, -1, 0);
72
73
74
75
76
77
78
#else
  ret = mmap(next_request, size, PROT_READ | PROT_WRITE, 
	     MAP_ANON | MAP_PRIVATE, -1, 0);
#endif
  
  if (ret == (void *)-1) {
    if (errno == ENOMEM) {
sof's avatar
sof committed
79
      barf("getMBlock: out of memory (blocks requested: %d)", n);
80
81
82
83
84
85
    } else {
      barf("GetMBlock: mmap failed");
    }
  }

  if (((W_)ret & MBLOCK_MASK) != 0) {
86
    barf("GetMBlock: misaligned block %p returned when allocating %d megablock(s) at %p", ret, n, next_request);
87
88
  }

ken's avatar
ken committed
89
  IF_DEBUG(gc,fprintf(stderr,"Allocated %d megablock(s) at %p\n",n,ret));
90
91
92

  next_request += size;

93
94
  mblocks_allocated += n;
  
95
96
  return ret;
}
sof's avatar
sof committed
97

sof's avatar
sof committed
98
#else /* defined(mingw32_TARGET_OS) || defined(cygwin32_TARGET_OS) */
sof's avatar
sof committed
99
100
101
102
103

/*
 On Win32 platforms we make use of the two-phased virtual memory API
 to allocate mega blocks. We proceed as follows:

sof's avatar
sof committed
104
105
106
107
108
 Reserve a large chunk of VM (256M at the time, or what the user asked
 for via the -M option), but don't supply a base address that's aligned on
 a MB boundary. Instead we round up to the nearest mblock from the chunk of
 VM we're handed back from the OS (at the moment we just leave the 'slop' at
 the beginning of the reserved chunk unused - ToDo: reuse it .)
sof's avatar
sof committed
109
110

 Reserving memory doesn't allocate physical storage (not even in the
sof's avatar
sof committed
111
 page file), this is done later on by committing pages (or mega-blocks in
sof's avatar
sof committed
112
113
114
 our case).
*/

sof's avatar
sof committed
115
char* base_non_committed = (char*)0;
sof's avatar
sof committed
116
char* end_non_committed = (char*)0;
sof's avatar
sof committed
117

sof's avatar
sof committed
118
/* Default is to reserve 256M of VM to minimise the slop cost. */
119
#define SIZE_RESERVED_POOL  ( 256 * 1024 * 1024 )
sof's avatar
sof committed
120

sof's avatar
sof committed
121
122
123
/* Number of bytes reserved */
static unsigned long size_reserved_pool = SIZE_RESERVED_POOL;

sof's avatar
sof committed
124
/* This predicate should be inlined, really. */
rrt's avatar
rrt committed
125
/* TODO: this only works for a single chunk */
sof's avatar
sof committed
126
127
128
129
int
is_heap_alloced(const void* x)
{
  return (((char*)(x) >= base_non_committed) && 
sof's avatar
sof committed
130
          ((char*)(x) <= end_non_committed));
sof's avatar
sof committed
131
132
}

sof's avatar
sof committed
133
134
135
136
137
138
139
140
void *
getMBlocks(nat n)
{
  static char* base_mblocks       = (char*)0;
  static char* next_request       = (char*)0;
  void* ret                       = (void*)0;

  lnat size = MBLOCK_SIZE * n;
sof's avatar
sof committed
141
142
143
144
145
146
147
148
149
150
151
  
  if ( (base_non_committed == 0) || (next_request + size > end_non_committed) ) {
    if (base_non_committed) {
      barf("RTS exhausted max heap size (%d bytes)\n", size_reserved_pool);
    }
    if (RtsFlags.GcFlags.maxHeapSize != 0) {
      size_reserved_pool = BLOCK_SIZE * RtsFlags.GcFlags.maxHeapSize;
      if (size_reserved_pool < MBLOCK_SIZE) {
	size_reserved_pool = 2*MBLOCK_SIZE;
      }
    }
sof's avatar
sof committed
152
    base_non_committed = VirtualAlloc ( NULL
sof's avatar
sof committed
153
                                      , size_reserved_pool
sof's avatar
sof committed
154
155
156
157
				      , MEM_RESERVE
				      , PAGE_READWRITE
				      );
    if ( base_non_committed == 0 ) {
158
         fprintf(stderr, "getMBlocks: VirtualAlloc failed with: %ld\n", GetLastError());
sof's avatar
sof committed
159
160
         ret=(void*)-1;
    } else {
sof's avatar
sof committed
161
162
163
      end_non_committed = (char*)base_non_committed + (unsigned long)size_reserved_pool;
      /* The returned pointer is not aligned on a mega-block boundary. Make it. */
      base_mblocks = (char*)((unsigned long)base_non_committed & (unsigned long)0xfff00000) + MBLOCK_SIZE;
164
165
#      if 0
       fprintf(stderr, "getMBlocks: Dropping %d bytes off of 256M chunk\n", 
sof's avatar
sof committed
166
	               (unsigned)base_mblocks - (unsigned)base_non_committed);
167
#      endif
sof's avatar
sof committed
168

sof's avatar
sof committed
169
       if ( ((char*)base_mblocks + size) > end_non_committed ) {
170
          fprintf(stderr, "getMBlocks: oops, committed too small a region to start with.");
sof's avatar
sof committed
171
172
173
174
175
176
177
178
179
180
	  ret=(void*)-1;
       } else {
          next_request = base_mblocks;
       }
    }
  }
  /* Commit the mega block(s) to phys mem */
  if ( ret != (void*)-1 ) {
     ret = VirtualAlloc(next_request, size, MEM_COMMIT, PAGE_READWRITE);
     if (ret == NULL) {
181
        fprintf(stderr, "getMBlocks: VirtualAlloc failed with: %ld\n", GetLastError());
sof's avatar
sof committed
182
183
184
185
186
        ret=(void*)-1;
     }
  }

  if (((W_)ret & MBLOCK_MASK) != 0) {
187
    barf("getMBlocks: misaligned block returned");
sof's avatar
sof committed
188
189
  }

190
191
192
  if (ret == (void*)-1) {
     barf("getMBlocks: unknown memory allocation failure on Win32.");
  }
sof's avatar
sof committed
193

194
  IF_DEBUG(gc,fprintf(stderr,"Allocated %d megablock(s) at 0x%x\n",n,(nat)ret));
sof's avatar
sof committed
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
  next_request = (char*)next_request + size;

  mblocks_allocated += n;
  
  return ret;
}

/* Hand back the physical memory that is allocated to a mega-block. 
   ToDo: chain the released mega block onto some list so that
         getMBlocks() can get at it.

   Currently unused.
*/
#if 0
void
freeMBlock(void* p, nat n)
{
  BOOL rc;

  rc = VirtualFree(p, n * MBLOCK_SIZE , MEM_DECOMMIT );
  
  if (rc == FALSE) {
217
#    ifdef DEBUG
sof's avatar
sof committed
218
     fprintf(stderr, "freeMBlocks: VirtualFree failed with: %d\n", GetLastError());
219
#    endif
sof's avatar
sof committed
220
221
222
223
224
225
  }

}
#endif

#endif