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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/tile/lib/memmove.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/tile/lib/memmove.c')
-rw-r--r--kernel/arch/tile/lib/memmove.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/kernel/arch/tile/lib/memmove.c b/kernel/arch/tile/lib/memmove.c
new file mode 100644
index 000000000..fd615ae6a
--- /dev/null
+++ b/kernel/arch/tile/lib/memmove.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program 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, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/module.h>
+
+void *memmove(void *dest, const void *src, size_t n)
+{
+ if ((const char *)src >= (char *)dest + n
+ || (char *)dest >= (const char *)src + n) {
+ /* We found no overlap, so let memcpy do all the heavy
+ * lifting (prefetching, etc.)
+ */
+ return memcpy(dest, src, n);
+ }
+
+ if (n != 0) {
+ const uint8_t *in;
+ uint8_t x;
+ uint8_t *out;
+ int stride;
+
+ if (src < dest) {
+ /* copy backwards */
+ in = (const uint8_t *)src + n - 1;
+ out = (uint8_t *)dest + n - 1;
+ stride = -1;
+ } else {
+ /* copy forwards */
+ in = (const uint8_t *)src;
+ out = (uint8_t *)dest;
+ stride = 1;
+ }
+
+ /* Manually software-pipeline this loop. */
+ x = *in;
+ in += stride;
+
+ while (--n != 0) {
+ *out = x;
+ out += stride;
+ x = *in;
+ in += stride;
+ }
+
+ *out = x;
+ }
+
+ return dest;
+}
+EXPORT_SYMBOL(memmove);