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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/x86/lib/cmpxchg8b_emu.S
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/x86/lib/cmpxchg8b_emu.S')
-rw-r--r--kernel/arch/x86/lib/cmpxchg8b_emu.S55
1 files changed, 55 insertions, 0 deletions
diff --git a/kernel/arch/x86/lib/cmpxchg8b_emu.S b/kernel/arch/x86/lib/cmpxchg8b_emu.S
new file mode 100644
index 000000000..b4807fce5
--- /dev/null
+++ b/kernel/arch/x86/lib/cmpxchg8b_emu.S
@@ -0,0 +1,55 @@
+/*
+ * 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
+ * of the License.
+ *
+ */
+
+#include <linux/linkage.h>
+#include <asm/dwarf2.h>
+
+.text
+
+/*
+ * Inputs:
+ * %esi : memory location to compare
+ * %eax : low 32 bits of old value
+ * %edx : high 32 bits of old value
+ * %ebx : low 32 bits of new value
+ * %ecx : high 32 bits of new value
+ */
+ENTRY(cmpxchg8b_emu)
+CFI_STARTPROC
+
+#
+# Emulate 'cmpxchg8b (%esi)' on UP except we don't
+# set the whole ZF thing (caller will just compare
+# eax:edx with the expected value)
+#
+ pushfl_cfi
+ cli
+
+ cmpl (%esi), %eax
+ jne .Lnot_same
+ cmpl 4(%esi), %edx
+ jne .Lhalf_same
+
+ movl %ebx, (%esi)
+ movl %ecx, 4(%esi)
+
+ CFI_REMEMBER_STATE
+ popfl_cfi
+ ret
+
+ CFI_RESTORE_STATE
+.Lnot_same:
+ movl (%esi), %eax
+.Lhalf_same:
+ movl 4(%esi), %edx
+
+ popfl_cfi
+ ret
+
+CFI_ENDPROC
+ENDPROC(cmpxchg8b_emu)