X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=libringbuffer%2Fbackend_internal.h;h=373e3147e383c143dc7273253d584f922a421a50;hb=refs%2Fheads%2Fstable-2.0;hp=f61d1d61bc0a2cce0ca84469aa79093960937e7a;hpb=a3f61e7f689a5fc60b833a773f462989dc6cc78f;p=lttng-ust.git

diff --git a/libringbuffer/backend_internal.h b/libringbuffer/backend_internal.h
index f61d1d61..373e3147 100644
--- a/libringbuffer/backend_internal.h
+++ b/libringbuffer/backend_internal.h
@@ -1,14 +1,26 @@
-#ifndef _LINUX_RING_BUFFER_BACKEND_INTERNAL_H
-#define _LINUX_RING_BUFFER_BACKEND_INTERNAL_H
+#ifndef _LTTNG_RING_BUFFER_BACKEND_INTERNAL_H
+#define _LTTNG_RING_BUFFER_BACKEND_INTERNAL_H
 
 /*
- * linux/ringbuffer/backend_internal.h
- *
- * Copyright (C) 2008-2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * libringbuffer/backend_internal.h
  *
  * Ring buffer backend (internal helpers).
  *
- * Dual LGPL v2.1/GPL v2 license.
+ * Copyright (C) 2005-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <unistd.h>
@@ -416,6 +428,10 @@ int update_read_sb_index(const struct lttng_ust_lib_ring_buffer_config *config,
 	return 0;
 }
 
+#ifndef inline_memcpy
+#define inline_memcpy(dest, src, n)	memcpy(dest, src, n)
+#endif
+
 /*
  * Use the architecture-specific memcpy implementation for constant-sized
  * inputs, but rely on an inline memcpy for length statically unknown.
@@ -430,4 +446,45 @@ do {								\
 		inline_memcpy(dest, src, __len);		\
 } while (0)
 
-#endif /* _LINUX_RING_BUFFER_BACKEND_INTERNAL_H */
+/* arch-agnostic implementation */
+
+static inline int fls(unsigned int x)
+{
+	int r = 32;
+
+	if (!x)
+		return 0;
+	if (!(x & 0xFFFF0000U)) {
+		x <<= 16;
+		r -= 16;
+	}
+	if (!(x & 0xFF000000U)) {
+		x <<= 8;
+		r -= 8;
+	}
+	if (!(x & 0xF0000000U)) {
+		x <<= 4;
+		r -= 4;
+	}
+	if (!(x & 0xC0000000U)) {
+		x <<= 2;
+		r -= 2;
+	}
+	if (!(x & 0x80000000U)) {
+		x <<= 1;
+		r -= 1;
+	}
+	return r;
+}
+
+static inline int get_count_order(unsigned int count)
+{
+	int order;
+
+	order = fls(count) - 1;
+	if (count & (count - 1))
+		order++;
+	return order;
+}
+
+#endif /* _LTTNG_RING_BUFFER_BACKEND_INTERNAL_H */