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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/s390/include/asm/jump_label.h
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/s390/include/asm/jump_label.h')
-rw-r--r--kernel/arch/s390/include/asm/jump_label.h37
1 files changed, 37 insertions, 0 deletions
diff --git a/kernel/arch/s390/include/asm/jump_label.h b/kernel/arch/s390/include/asm/jump_label.h
new file mode 100644
index 000000000..69972b795
--- /dev/null
+++ b/kernel/arch/s390/include/asm/jump_label.h
@@ -0,0 +1,37 @@
+#ifndef _ASM_S390_JUMP_LABEL_H
+#define _ASM_S390_JUMP_LABEL_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+
+#define JUMP_LABEL_NOP_SIZE 6
+#define JUMP_LABEL_NOP_OFFSET 2
+
+/*
+ * We use a brcl 0,2 instruction for jump labels at compile time so it
+ * can be easily distinguished from a hotpatch generated instruction.
+ */
+static __always_inline bool arch_static_branch(struct static_key *key)
+{
+ asm_volatile_goto("0: brcl 0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n"
+ ".pushsection __jump_table, \"aw\"\n"
+ ".balign 8\n"
+ ".quad 0b, %l[label], %0\n"
+ ".popsection\n"
+ : : "X" (key) : : label);
+ return false;
+label:
+ return true;
+}
+
+typedef unsigned long jump_label_t;
+
+struct jump_entry {
+ jump_label_t code;
+ jump_label_t target;
+ jump_label_t key;
+};
+
+#endif /* __ASSEMBLY__ */
+#endif