1 files changed, 110 insertions, 0 deletions
diff --git a/erts/emulator/beam/code_ix.c b/erts/emulator/beam/code_ix.c
new file mode 100644
index 0000000000..a8b6599e61
--- /dev/null
+++ b/erts/emulator/beam/code_ix.c
@@ -0,0 +1,110 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2012. All Rights Reserved.
+ *
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include "code_ix.h"
+#include "global.h"
+#include "beam_catches.h"
+
+
+
+#if 0
+# define CIX_TRACE(text) erts_fprintf(stderr, "CIX_TRACE: " text " act=%u load=%u\r\n", erts_active_code_ix(), erts_staging_code_ix())
+#else
+# define CIX_TRACE(text)
+#endif
+
+erts_smp_atomic32_t the_active_code_index;
+erts_smp_atomic32_t the_staging_code_index;
+
+static erts_smp_mtx_t sverk_code_ix_lock; /*SVERK FIXME */
+
+void erts_code_ix_init(void)
+{
+    /* We start emulator by initializing preloaded modules
+     * single threaded with active and staging set both to zero.
+     * Preloading is finished by a commit that will set things straight.
+     */
+    erts_smp_atomic32_init_nob(&the_active_code_index, 0);
+    erts_smp_atomic32_init_nob(&the_staging_code_index, 0);
+    erts_smp_mtx_init_x(&sverk_code_ix_lock, "sverk_code_ix_lock", NIL); /*SVERK FIXME */
+    CIX_TRACE("init");
+}
+
+void erts_start_staging_code_ix(void)
+{
+    beam_catches_start_staging();
+    export_start_staging();
+    module_start_staging();
+    erts_start_staging_ranges();
+    CIX_TRACE("start");
+}
+
+
+void erts_commit_staging_code_ix(void)
+{
+    beam_catches_end_staging(1);
+    export_end_staging(1);
+    module_end_staging(1);
+    erts_end_staging_ranges(1);
+    {
+	ErtsCodeIndex ix;
+	export_write_lock();
+	ix = erts_staging_code_ix();
+	erts_smp_atomic32_set_nob(&the_active_code_index, ix);
+	ix = (ix + 1) % ERTS_NUM_CODE_IX;
+	erts_smp_atomic32_set_nob(&the_staging_code_index, ix);
+	export_write_unlock();
+    }
+    CIX_TRACE("commit");
+}
+
+void erts_abort_staging_code_ix(void)
+{
+    beam_catches_end_staging(0);
+    export_end_staging(0);
+    module_end_staging(0);
+    erts_end_staging_ranges(0);
+    CIX_TRACE("abort");
+}
+
+
+/* Lock code_ix (enqueue and suspend until we get it)
+*/
+void erts_lock_code_ix(void)
+{
+    erts_smp_mtx_lock(&sverk_code_ix_lock); /*SVERK FIXME */
+}
+
+/* Unlock code_ix (resume first waiter)
+*/
+void erts_unlock_code_ix(void)
+{
+    erts_smp_mtx_unlock(&sverk_code_ix_lock); /*SVERK FIXME */
+}
+
+#ifdef ERTS_ENABLE_LOCK_CHECK
+int erts_is_code_ix_locked(void)
+{
+    return erts_smp_lc_mtx_is_locked(&sverk_code_ix_lock);
+}
+#endif