ghc/rts/Storage.h

   1 /* -----------------------------------------------------------------------------
   2  * $Id: Storage.h,v 1.10 1999/11/02 15:06:05 simonmar Exp $
   3  *
   4  * (c) The GHC Team, 1998-1999
   5  *
   6  * External Storage Manger Interface
   7  *
   8  * ---------------------------------------------------------------------------*/
   9
  10 #ifndef STORAGE_H
  11 #define STORAGE_H
  12
  13 #include "Block.h"
  14 #include "BlockAlloc.h"
  15 #include "StoragePriv.h"
  16
  17 /* -----------------------------------------------------------------------------
  18    Initialisation / De-initialisation
  19    -------------------------------------------------------------------------- */
  20
  21 extern void initStorage(void);
  22 extern void exitStorage(void);
  23
  24 /* -----------------------------------------------------------------------------
  25    Generic allocation
  26
  27    StgPtr allocate(int n)       Allocates a chunk of contiguous store
  28                                 n words long, returning a pointer to
  29                                 the first word.  Always succeeds.
  30
  31                                 Don't forget to TICK_ALLOC_XXX(...)
  32                                 after calling allocate, for the
  33                                 benefit of the ticky-ticky profiler.
  34
  35    rtsBool doYouWantToGC(void)  Returns True if the storage manager is
  36                                 ready to perform a GC, False otherwise.
  37
  38    lnat  allocated_bytes(void)  Returns the number of bytes allocated
  39                                 via allocate() since the last GC.
  40                                 Used in the reoprting of statistics.
  41
  42    SMP: allocate and doYouWantToGC can be used from STG code, they are
  43    surrounded by a mutex.
  44    -------------------------------------------------------------------------- */
  45
  46 extern StgPtr  allocate(nat n);
  47 static inline rtsBool doYouWantToGC(void)
  48 {
  49   return (alloc_blocks >= alloc_blocks_lim);
  50 }
  51 extern lnat allocated_bytes(void);
  52
  53 /* -----------------------------------------------------------------------------
  54    ExtendNursery(hp,hplim)      When hplim is reached, try to grab
  55                                 some more allocation space.  Returns
  56                                 False if the allocation space is
  57                                 exhausted, and the application should
  58                                 call GarbageCollect().
  59   -------------------------------------------------------------------------- */
  60
  61 #define ExtendNursery(hp,hplim)                 \
  62   (CurrentNursery->free = (P_)(hp)+1,           \
  63    CurrentNursery->link == NULL ? rtsFalse :    \
  64    (CurrentNursery = CurrentNursery->link,      \
  65     OpenNursery(hp,hplim),                      \
  66     rtsTrue))
  67
  68 extern void PleaseStopAllocating(void);
  69
  70 /* -----------------------------------------------------------------------------
  71    Performing Garbage Collection
  72
  73    GarbageCollect(get_roots)    Performs a garbage collection.
  74                                 'get_roots' is called to find all the
  75                                 roots that the system knows about.
  76
  77    StgClosure                   Called by get_roots on each root.
  78    MarkRoot(StgClosure *p)      Returns the new location of the root.
  79    -------------------------------------------------------------------------- */
  80
  81 extern void   GarbageCollect(void (*get_roots)(void));
  82 extern StgClosure *MarkRoot(StgClosure *p);
  83
  84 /* -----------------------------------------------------------------------------
  85    Generational garbage collection support
  86
  87    recordMutable(StgPtr p)       Informs the garbage collector that a
  88                                  previously immutable object has
  89                                  become (permanently) mutable.  Used
  90                                  by thawArray and similar.
  91
  92    updateWithIndirection(p1,p2)  Updates the object at p1 with an
  93                                  indirection pointing to p2.  This is
  94                                  normally called for objects in an old
  95                                  generation (>0) when they are updated.
  96
  97    updateWithPermIndirection(p1,p2)  As above but uses a permanent indir.
  98
  99    -------------------------------------------------------------------------- */
 100
 101 static inline void
 102 recordMutable(StgMutClosure *p)
 103 {
 104   bdescr *bd;
 105
 106 #ifdef SMP
 107   ASSERT(p->header.info == &WHITEHOLE_info || closure_MUTABLE(p));
 108 #else
 109   ASSERT(closure_MUTABLE(p));
 110 #endif
 111
 112   bd = Bdescr((P_)p);
 113   if (bd->gen->no > 0) {
 114     p->mut_link = bd->gen->mut_list;
 115     bd->gen->mut_list = p;
 116   }
 117 }
 118
 119 static inline void
 120 recordOldToNewPtrs(StgMutClosure *p)
 121 {
 122   bdescr *bd;
 123
 124   bd = Bdescr((P_)p);
 125   if (bd->gen->no > 0) {
 126     p->mut_link = bd->gen->mut_once_list;
 127     bd->gen->mut_once_list = p;
 128   }
 129 }
 130
 131 #define updateWithIndirection(p1, p2)                           \
 132   {                                                             \
 133     bdescr *bd;                                                 \
 134                                                                 \
 135     bd = Bdescr((P_)p1);                                        \
 136     if (bd->gen->no == 0) {                                     \
 137       ((StgInd *)p1)->indirectee = p2;                          \
 138       SET_INFO(p1,&IND_info);                                   \
 139       TICK_UPD_NEW_IND();                                       \
 140     } else {                                                    \
 141       ((StgIndOldGen *)p1)->indirectee = p2;                    \
 142       ((StgIndOldGen *)p1)->mut_link = bd->gen->mut_once_list;  \
 143       bd->gen->mut_once_list = (StgMutClosure *)p1;             \
 144       SET_INFO(p1,&IND_OLDGEN_info);                            \
 145       TICK_UPD_OLD_IND();                                       \
 146     }                                                           \
 147   }
 148
 149 #if defined(TICKY_TICKY) || defined(PROFILING)
 150 static inline void
 151 updateWithPermIndirection(StgClosure *p1, StgClosure *p2)
 152 {
 153   bdescr *bd;
 154
 155   bd = Bdescr((P_)p1);
 156   if (bd->gen->no == 0) {
 157     ((StgInd *)p1)->indirectee = p2;
 158     SET_INFO(p1,&IND_PERM_info);
 159     TICK_UPD_NEW_PERM_IND(p1);
 160   } else {
 161     ((StgIndOldGen *)p1)->indirectee = p2;
 162     ((StgIndOldGen *)p1)->mut_link = bd->gen->mut_once_list;
 163     bd->gen->mut_once_list = (StgMutClosure *)p1;
 164     SET_INFO(p1,&IND_OLDGEN_PERM_info);
 165     TICK_UPD_OLD_PERM_IND();
 166   }
 167 }
 168 #endif
 169
 170 /* -----------------------------------------------------------------------------
 171    The CAF list - used to let us revert CAFs
 172
 173    -------------------------------------------------------------------------- */
 174
 175 extern StgCAF* enteredCAFs;
 176
 177 #endif STORAGE_H
 178