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                 /* This is an abuse of the collection thread, but it's
  40                  * better than creating a new thread just for one more
  41                  * function.
  42                  */
  43                 _wapi_process_reap ();
  44         }
  45
  46         pthread_exit (NULL);
  47
  48         return(NULL);
  49 }
  50
  51 void _wapi_collection_init (void)
  52 {
  53         pthread_attr_t attr;
  54         int ret;
  55         int set_stacksize = 0;
  56
  57  retry:
  58         ret = pthread_attr_init (&attr);
  59         g_assert (ret == 0);
  60
  61 #ifdef HAVE_PTHREAD_ATTR_SETSTACKSIZE
  62         if (set_stacksize == 0) {
  63 #if defined(__FreeBSD__) || defined(__NetBSD__)
  64                 ret = pthread_attr_setstacksize (&attr, 65536);
  65 #else
  66                 ret = pthread_attr_setstacksize (&attr, PTHREAD_STACK_MIN);
  67 #endif
  68                 g_assert (ret == 0);
  69         } else if (set_stacksize == 1) {
  70                 ret = pthread_attr_setstacksize (&attr, 131072);
  71                 g_assert (ret == 0);
  72         }
  73 #endif
  74
  75         ret = pthread_create (&collection_thread_id, &attr, collection_thread,
  76                               NULL);
  77         if (ret != 0 && set_stacksize < 2) {
  78                 set_stacksize++;
  79                 goto retry;
  80         }
  81         if (ret != 0) {
  82                 g_error ("%s: Couldn't create handle collection thread: %s",
  83                          __func__, g_strerror (ret));
  84         }
  85 }
  86
  87 void _wapi_handle_collect (void)
  88 {
  89         guint32 count = _wapi_shared_layout->collection_count;
  90         int i, thr_ret;
  91
  92         LOGDEBUG ("%s: (%d) Starting a collection", __func__, _wapi_getpid ());
  93
  94         /* Become the collection master */
  95         thr_ret = _wapi_handle_lock_shared_handles ();
  96         g_assert (thr_ret == 0);
  97
  98         LOGDEBUG ("%s: (%d) Master set", __func__, _wapi_getpid ());
  99
 100         /* If count has changed, someone else jumped in as master */
 101         if (count == _wapi_shared_layout->collection_count) {
 102                 guint32 too_old = (guint32)(time(NULL) & 0xFFFFFFFF) - _WAPI_HANDLE_COLLECTION_EXPIRED_INTERVAL;
 103
 104                 for (i = 0; i < _WAPI_HANDLE_INITIAL_COUNT; i++) {
 105                         struct _WapiHandleShared *data;
 106
 107                         data = &_wapi_shared_layout->handles[i];
 108                         if (data->timestamp < too_old) {
 109                                 LOGDEBUG ("%s: (%d) Deleting handle 0x%x", __func__, _wapi_getpid (), i);
 110                                 memset (&_wapi_shared_layout->handles[i], '\0', sizeof(struct _WapiHandleShared));
 111                         }
 112                 }
 113
 114                 for (i = 0; i < _wapi_fileshare_layout->hwm; i++) {
 115                         struct _WapiFileShare *file_share = &_wapi_fileshare_layout->share_info[i];
 116
 117                         if (file_share->timestamp < too_old) {
 118                                 memset (file_share, '\0',
 119                                         sizeof(struct _WapiFileShare));
 120                         }
 121                 }
 122
 123                 InterlockedIncrement ((gint32 *)&_wapi_shared_layout->collection_count);
 124         }
 125
 126         _wapi_handle_unlock_shared_handles ();
 127
 128         LOGDEBUG ("%s: (%d) Collection done", __func__, _wapi_getpid ());
 129 }