boehm-gc/include/private/pthread_support.h

   1 #ifndef GC_PTHREAD_SUPPORT_H
   2 #define GC_PTHREAD_SUPPORT_H
   3
   4 # include "private/gc_priv.h"
   5
   6 # if defined(GC_PTHREADS) && !defined(GC_SOLARIS_THREADS) \
   7      && !defined(GC_WIN32_THREADS)
   8
   9 #if defined(GC_DARWIN_THREADS)
  10 # include "private/darwin_stop_world.h"
  11 #else
  12 # include "private/pthread_stop_world.h"
  13 #endif
  14
  15 /* We use the allocation lock to protect thread-related data structures. */
  16
  17 /* The set of all known threads.  We intercept thread creation and      */
  18 /* joins.                                                               */
  19 /* Protected by allocation/GC lock.                                     */
  20 /* Some of this should be declared volatile, but that's inconsistent    */
  21 /* with some library routine declarations.                              */
  22 typedef struct GC_Thread_Rep {
  23     struct GC_Thread_Rep * next;  /* More recently allocated threads    */
  24                                   /* with a given pthread id come       */
  25                                   /* first.  (All but the first are     */
  26                                   /* guaranteed to be dead, but we may  */
  27                                   /* not yet have registered the join.) */
  28     pthread_t id;
  29     /* Extra bookkeeping information the stopping code uses */
  30     struct thread_stop_info stop_info;
  31
  32     short flags;
  33 #       define FINISHED 1       /* Thread has exited.   */
  34 #       define DETACHED 2       /* Thread is intended to be detached.   */
  35 #       define MAIN_THREAD 4    /* True for the original thread only.   */
  36 #       define SUSPENDED 8      /* True if thread was suspended externally */
  37     short thread_blocked;       /* Protected by GC lock.                */
  38                                 /* Treated as a boolean value.  If set, */
  39                                 /* thread will acquire GC lock before   */
  40                                 /* doing any pointer manipulations, and */
  41                                 /* has set its sp value.  Thus it does  */
  42                                 /* not need to be sent a signal to stop */
  43                                 /* it.                                  */
  44     ptr_t stack_end;            /* Cold end of the stack.               */
  45 #   ifdef IA64
  46         ptr_t backing_store_end;
  47         ptr_t backing_store_ptr;
  48 #   endif
  49     void * status;              /* The value returned from the thread.  */
  50                                 /* Used only to avoid premature         */
  51                                 /* reclamation of any data it might     */
  52                                 /* reference.                           */
  53 #   ifdef THREAD_LOCAL_ALLOC
  54 #       if CPP_WORDSZ == 64 && defined(ALIGN_DOUBLE)
  55 #           define GRANULARITY 16
  56 #           define NFREELISTS 49
  57 #       else
  58 #           define GRANULARITY 8
  59 #           define NFREELISTS 65
  60 #       endif
  61         /* The ith free list corresponds to size i*GRANULARITY */
  62 #       define INDEX_FROM_BYTES(n) ((ADD_SLOP(n) + GRANULARITY - 1)/GRANULARITY)
  63 #       define BYTES_FROM_INDEX(i) ((i) * GRANULARITY - EXTRA_BYTES)
  64 #       define SMALL_ENOUGH(bytes) (ADD_SLOP(bytes) <= \
  65                                     (NFREELISTS-1)*GRANULARITY)
  66         ptr_t ptrfree_freelists[NFREELISTS];
  67         ptr_t normal_freelists[NFREELISTS];
  68 #       ifdef GC_GCJ_SUPPORT
  69           ptr_t gcj_freelists[NFREELISTS];
  70 #       endif
  71                 /* Free lists contain either a pointer or a small count */
  72                 /* reflecting the number of granules allocated at that  */
  73                 /* size.                                                */
  74                 /* 0 ==> thread-local allocation in use, free list      */
  75                 /*       empty.                                         */
  76                 /* > 0, <= DIRECT_GRANULES ==> Using global allocation, */
  77                 /*       too few objects of this size have been         */
  78                 /*       allocated by this thread.                      */
  79                 /* >= HBLKSIZE  => pointer to nonempty free list.       */
  80                 /* > DIRECT_GRANULES, < HBLKSIZE ==> transition to      */
  81                 /*    local alloc, equivalent to 0.                     */
  82 #       define DIRECT_GRANULES (HBLKSIZE/GRANULARITY)
  83                 /* Don't use local free lists for up to this much       */
  84                 /* allocation.                                          */
  85 #   endif
  86 } * GC_thread;
  87
  88 # define THREAD_TABLE_SZ 128    /* Must be power of 2   */
  89 extern volatile GC_thread GC_threads[THREAD_TABLE_SZ];
  90
  91 extern GC_bool GC_thr_initialized;
  92
  93 GC_thread GC_lookup_thread(pthread_t id);
  94
  95 void GC_stop_init();
  96
  97 extern GC_bool GC_in_thread_creation;
  98         /* We may currently be in thread creation or destruction.       */
  99         /* Only set to TRUE while allocation lock is held.              */
 100         /* When set, it is OK to run GC from unknown thread.            */
 101
 102 #endif /* GC_PTHREADS && !GC_SOLARIS_THREADS.... etc */
 103 #endif /* GC_PTHREAD_SUPPORT_H */