static guint32 _wapi_private_handle_slot_count = 0;
struct _WapiHandleSharedLayout *_wapi_shared_layout = NULL;
+
+/*
+ * If SHM is enabled, this will point to shared memory, otherwise it will be NULL.
+ */
struct _WapiFileShareLayout *_wapi_fileshare_layout = NULL;
+/*
+ * If SHM is disabled, this will point to a hash of _WapiFileShare structures, otherwise
+ * it will be NULL. We use this instead of _wapi_fileshare_layout to avoid allocating a
+ * 4MB array.
+ */
+static GHashTable *file_share_hash;
+static CRITICAL_SECTION file_share_hash_mutex;
+
+#define file_share_hash_lock() EnterCriticalSection (&file_share_hash_mutex)
+#define file_share_hash_unlock() LeaveCriticalSection (&file_share_hash_mutex)
+
guint32 _wapi_fd_reserve;
/*
}
_wapi_shm_semaphores_remove ();
+
+ _wapi_shm_detach (WAPI_SHM_DATA);
+ _wapi_shm_detach (WAPI_SHM_FILESHARE);
+
+ if (file_share_hash) {
+ g_hash_table_destroy (file_share_hash);
+ DeleteCriticalSection (&file_share_hash_mutex);
+ }
+
+ for (i = 0; i < _WAPI_PRIVATE_MAX_SLOTS; ++i)
+ g_free (_wapi_private_handles [i]);
}
void _wapi_cleanup ()
_wapi_shared_layout = _wapi_shm_attach (WAPI_SHM_DATA);
g_assert (_wapi_shared_layout != NULL);
- _wapi_fileshare_layout = _wapi_shm_attach (WAPI_SHM_FILESHARE);
- g_assert (_wapi_fileshare_layout != NULL);
+ if (_wapi_shm_enabled ()) {
+ /* This allocates a 4mb array, so do it only if SHM is enabled */
+ _wapi_fileshare_layout = _wapi_shm_attach (WAPI_SHM_FILESHARE);
+ g_assert (_wapi_fileshare_layout != NULL);
+ }
#if !defined (DISABLE_SHARED_HANDLES)
- if (!g_getenv ("MONO_DISABLE_SHM"))
+ if (_wapi_shm_enabled ())
_wapi_collection_init ();
#endif
}
}
+void
+_wapi_free_share_info (_WapiFileShare *share_info)
+{
+ if (!_wapi_shm_enabled ()) {
+ file_share_hash_lock ();
+ g_hash_table_remove (file_share_hash, share_info);
+ file_share_hash_unlock ();
+ } else {
+ memset (share_info, '\0', sizeof(struct _WapiFileShare));
+ }
+}
+
+static gint
+wapi_share_info_equal (gconstpointer ka, gconstpointer kb)
+{
+ const _WapiFileShare *s1 = ka;
+ const _WapiFileShare *s2 = kb;
+
+ return (s1->device == s2->device && s1->inode == s2->inode) ? 1 : 0;
+}
+
+static guint
+wapi_share_info_hash (gconstpointer data)
+{
+ const _WapiFileShare *s = data;
+
+ return s->inode;
+}
+
gboolean _wapi_handle_get_or_set_share (dev_t device, ino_t inode,
guint32 new_sharemode,
guint32 new_access,
/* Prevent new entries racing with us */
thr_ret = _wapi_shm_sem_lock (_WAPI_SHARED_SEM_FILESHARE);
g_assert (thr_ret == 0);
-
- /* If a linear scan gets too slow we'll have to fit a hash
- * table onto the shared mem backing store
- */
- *share_info = NULL;
- for (i = 0; i <= _wapi_fileshare_layout->hwm; i++) {
- file_share = &_wapi_fileshare_layout->share_info[i];
- /* Make a note of an unused slot, in case we need to
- * store share info
+ if (!_wapi_shm_enabled ()) {
+ _WapiFileShare tmp;
+
+ /*
+ * Instead of allocating a 4MB array, we use a hash table to keep track of this
+ * info. This is needed even if SHM is disabled, to track sharing inside
+ * the current process.
*/
- if (first_unused == -1 && file_share->handle_refs == 0) {
- first_unused = i;
- continue;
+ if (!file_share_hash) {
+ file_share_hash = g_hash_table_new_full (wapi_share_info_hash, wapi_share_info_equal, NULL, g_free);
+ InitializeCriticalSection (&file_share_hash_mutex);
}
-
- if (file_share->handle_refs == 0) {
- continue;
- }
-
- if (file_share->device == device &&
- file_share->inode == inode) {
+
+ tmp.device = device;
+ tmp.inode = inode;
+
+ file_share_hash_lock ();
+
+ file_share = g_hash_table_lookup (file_share_hash, &tmp);
+ if (file_share) {
*old_sharemode = file_share->sharemode;
*old_access = file_share->access;
*share_info = file_share;
- /* Increment the reference count while we
- * still have sole access to the shared area.
- * This makes the increment atomic wrt
- * collections
- */
InterlockedIncrement ((gint32 *)&file_share->handle_refs);
-
exists = TRUE;
- break;
- }
- }
-
- if (!exists) {
- if (i == _WAPI_FILESHARE_SIZE && first_unused == -1) {
- /* No more space */
} else {
- if (first_unused == -1) {
- file_share = &_wapi_fileshare_layout->share_info[++i];
- _wapi_fileshare_layout->hwm = i;
- } else {
- file_share = &_wapi_fileshare_layout->share_info[first_unused];
- }
-
+ file_share = g_new0 (_WapiFileShare, 1);
+
file_share->device = device;
file_share->inode = inode;
file_share->opened_by_pid = _wapi_getpid ();
file_share->access = new_access;
file_share->handle_refs = 1;
*share_info = file_share;
+
+ g_hash_table_insert (file_share_hash, file_share, file_share);
}
- }
- if (*share_info != NULL) {
- InterlockedExchange ((gint32 *)&(*share_info)->timestamp, now);
+ file_share_hash_unlock ();
+ } else {
+ /* If a linear scan gets too slow we'll have to fit a hash
+ * table onto the shared mem backing store
+ */
+ *share_info = NULL;
+ for (i = 0; i <= _wapi_fileshare_layout->hwm; i++) {
+ file_share = &_wapi_fileshare_layout->share_info[i];
+
+ /* Make a note of an unused slot, in case we need to
+ * store share info
+ */
+ if (first_unused == -1 && file_share->handle_refs == 0) {
+ first_unused = i;
+ continue;
+ }
+
+ if (file_share->handle_refs == 0) {
+ continue;
+ }
+
+ if (file_share->device == device &&
+ file_share->inode == inode) {
+ *old_sharemode = file_share->sharemode;
+ *old_access = file_share->access;
+ *share_info = file_share;
+
+ /* Increment the reference count while we
+ * still have sole access to the shared area.
+ * This makes the increment atomic wrt
+ * collections
+ */
+ InterlockedIncrement ((gint32 *)&file_share->handle_refs);
+
+ exists = TRUE;
+ break;
+ }
+ }
+
+ if (!exists) {
+ if (i == _WAPI_FILESHARE_SIZE && first_unused == -1) {
+ /* No more space */
+ } else {
+ if (first_unused == -1) {
+ file_share = &_wapi_fileshare_layout->share_info[++i];
+ _wapi_fileshare_layout->hwm = i;
+ } else {
+ file_share = &_wapi_fileshare_layout->share_info[first_unused];
+ }
+
+ file_share->device = device;
+ file_share->inode = inode;
+ file_share->opened_by_pid = _wapi_getpid ();
+ file_share->sharemode = new_sharemode;
+ file_share->access = new_access;
+ file_share->handle_refs = 1;
+ *share_info = file_share;
+ }
+ }
+
+ if (*share_info != NULL) {
+ InterlockedExchange ((gint32 *)&(*share_info)->timestamp, now);
+ }
}
thr_ret = _wapi_shm_sem_unlock (_WAPI_SHARED_SEM_FILESHARE);
projects / mono.git / blobdiff