1 files changed, 99 insertions, 0 deletions
diff --git a/src/vppinfra/lock.h b/src/vppinfra/lock.h
new file mode 100644
index 00000000..7d241675
--- /dev/null
+++ b/src/vppinfra/lock.h
@@ -0,0 +1,99 @@
+/*
+ * 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_clib_lock_h
+#define included_clib_lock_h
+
+#include <vppinfra/clib.h>
+
+typedef struct
+{
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+  u32 lock;
+#if CLIB_DEBUG > 0
+  pid_t pid;
+  uword thread_index;
+  void *frame_address;
+#endif
+} *clib_spinlock_t;
+
+static inline void
+clib_spinlock_init (clib_spinlock_t * p)
+{
+  *p = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES, CLIB_CACHE_LINE_BYTES);
+  memset ((void *) *p, 0, CLIB_CACHE_LINE_BYTES);
+}
+
+static inline void
+clib_spinlock_free (clib_spinlock_t * p)
+{
+  if (*p)
+    {
+      clib_mem_free ((void *) *p);
+      *p = 0;
+    }
+}
+
+static_always_inline void
+clib_spinlock_lock (clib_spinlock_t * p)
+{
+  while (__sync_lock_test_and_set (&(*p)->lock, 1))
+#if __x86_64__
+    __builtin_ia32_pause ()
+#endif
+      ;
+#if CLIB_DEBUG > 0
+  (*p)->frame_address = __builtin_frame_address (0);
+  (*p)->pid = getpid ();
+  (*p)->thread_index = os_get_thread_index ();
+#endif
+}
+
+static_always_inline void
+clib_spinlock_lock_if_init (clib_spinlock_t * p)
+{
+  if (PREDICT_FALSE (*p != 0))
+    clib_spinlock_lock (p);
+}
+
+static_always_inline void
+clib_spinlock_unlock (clib_spinlock_t * p)
+{
+#if CLIB_DEBUG > 0
+  (*p)->frame_address = 0;
+  (*p)->pid = 0;
+  (*p)->thread_index = 0;
+#endif
+  /* Make sure all writes are complete before releasing the lock */
+  CLIB_MEMORY_BARRIER ();
+  (*p)->lock = 0;
+}
+
+static_always_inline void
+clib_spinlock_unlock_if_init (clib_spinlock_t * p)
+{
+  if (PREDICT_FALSE (*p != 0))
+    clib_spinlock_unlock (p);
+}
+
+#endif
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */