three-level timer wheel implementation w/ overflow vector
prep work for s/timing_wheel/tw_timer/ in the vlib process model
Change-Id: I763f4968a8fce1764a3778b12def0afbd30086b1
Signed-off-by: Dave Barach <dave@barachs.net>
diff --git a/src/vppinfra/tw_timer_4t_3w_256sl.h b/src/vppinfra/tw_timer_4t_3w_256sl.h
new file mode 100644
index 0000000..89adb7a
--- /dev/null
+++ b/src/vppinfra/tw_timer_4t_3w_256sl.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __included_tw_timer_4t_3w_256sl_h__
+#define __included_tw_timer_4t_3w_256sl_h__
+
+/* ... So that a client app can create multiple wheel geometries */
+#undef TW_TIMER_WHEELS
+#undef TW_SLOTS_PER_RING
+#undef TW_RING_SHIFT
+#undef TW_RING_MASK
+#undef TW_TIMERS_PER_OBJECT
+#undef LOG2_TW_TIMERS_PER_OBJECT
+#undef TW_SUFFIX
+#undef TW_OVERFLOW_VECTOR
+
+#define TW_TIMER_WHEELS 3
+#define TW_SLOTS_PER_RING 256
+#define TW_RING_SHIFT 8
+#define TW_RING_MASK (TW_SLOTS_PER_RING -1)
+#define TW_TIMERS_PER_OBJECT 4
+#define LOG2_TW_TIMERS_PER_OBJECT 2
+#define TW_SUFFIX _4t_3w_256sl
+
+#include <vppinfra/tw_timer_template.h>
+
+#endif /* __included_tw_timer_4t_3w_256sl_h__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */