mono/io-layer/collection.c

   1 /*
   2  * collection.c:  Garbage collection for handles
   3  *
   4  * Author:
   5  *      Dick Porter (dick@ximian.com)
   6  *
   7  * (C) 2004-2006 Novell, Inc.
   8  */
   9
  10 #include <config.h>
  11 #include <glib.h>
  12 #include <pthread.h>
  13 #include <signal.h>
  14 #include <sys/types.h>
  15 #include <unistd.h>
  16
  17 #include <mono/io-layer/wapi.h>
  18 #include <mono/io-layer/collection.h>
  19 #include <mono/io-layer/handles-private.h>
  20
  21 #define LOGDEBUG(...)
  22 // #define LOGDEBUG(...) g_message(__VA_ARGS__)
  23
  24 static pthread_t collection_thread_id;
  25
  26 static gpointer collection_thread (gpointer unused G_GNUC_UNUSED)
  27 {
  28         struct timespec sleepytime;
  29
  30         sleepytime.tv_sec = _WAPI_HANDLE_COLLECTION_UPDATE_INTERVAL;
  31         sleepytime.tv_nsec = 0;
  32
  33         while (_wapi_has_shut_down == FALSE) {
  34                 nanosleep (&sleepytime, NULL);
  35
  36                 //_wapi_handle_dump ();
  37                 _wapi_handle_update_refs ();
  38         }
  39
  40         pthread_exit (NULL);
  41
  42         return(NULL);
  43 }
  44
  45 void _wapi_collection_init (void)
  46 {
  47         pthread_attr_t attr;
  48         int ret;
  49         int set_stacksize = 0;
  50
  51  retry:
  52         ret = pthread_attr_init (&attr);
  53         g_assert (ret == 0);
  54
  55 #if defined(HAVE_PTHREAD_ATTR_SETSTACKSIZE)
  56         if (set_stacksize == 0) {
  57                         ret = pthread_attr_setstacksize (&attr, MAX (65536, PTHREAD_STACK_MIN));
  58                         g_assert (ret == 0);
  59         } else if (set_stacksize == 1) {
  60                         ret = pthread_attr_setstacksize (&attr, 131072);
  61                         g_assert (ret == 0);
  62         }
  63 #endif
  64
  65         ret = pthread_create (&collection_thread_id, &attr, collection_thread,
  66                               NULL);
  67         if (ret != 0 && set_stacksize < 2) {
  68                 set_stacksize++;
  69                 goto retry;
  70         }
  71         if (ret != 0) {
  72                 g_error ("%s: Couldn't create handle collection thread: %s",
  73                          __func__, g_strerror (ret));
  74         }
  75 }
  76
  77 void _wapi_handle_collect (void)
  78 {
  79         guint32 count = _wapi_shared_layout->collection_count;
  80         int i, thr_ret;
  81
  82         if (!_wapi_shm_enabled ())
  83                 return;
  84
  85         LOGDEBUG ("%s: (%d) Starting a collection", __func__, _wapi_getpid ());
  86
  87         /* Become the collection master */
  88         thr_ret = _wapi_handle_lock_shared_handles ();
  89         g_assert (thr_ret == 0);
  90
  91         LOGDEBUG ("%s: (%d) Master set", __func__, _wapi_getpid ());
  92
  93         /* If count has changed, someone else jumped in as master */
  94         if (count == _wapi_shared_layout->collection_count) {
  95                 guint32 too_old = (guint32)(time(NULL) & 0xFFFFFFFF) - _WAPI_HANDLE_COLLECTION_EXPIRED_INTERVAL;
  96
  97                 for (i = 0; i < _WAPI_HANDLE_INITIAL_COUNT; i++) {
  98                         struct _WapiHandleShared *data;
  99
 100                         data = &_wapi_shared_layout->handles[i];
 101                         if (data->timestamp < too_old) {
 102                                 LOGDEBUG ("%s: (%d) Deleting handle 0x%x", __func__, _wapi_getpid (), i);
 103                                 memset (&_wapi_shared_layout->handles[i], '\0', sizeof(struct _WapiHandleShared));
 104                         }
 105                 }
 106
 107                 for (i = 0; i < _wapi_fileshare_layout->hwm; i++) {
 108                         struct _WapiFileShare *file_share = &_wapi_fileshare_layout->share_info[i];
 109
 110                         if (file_share->timestamp < too_old) {
 111                                 memset (file_share, '\0',
 112                                         sizeof(struct _WapiFileShare));
 113                         }
 114                 }
 115
 116                 InterlockedIncrement ((gint32 *)&_wapi_shared_layout->collection_count);
 117         }
 118
 119         _wapi_handle_unlock_shared_handles ();
 120
 121         LOGDEBUG ("%s: (%d) Collection done", __func__, _wapi_getpid ());
 122 }