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-rw-r--r--arch/powerpc/Kconfig1
-rw-r--r--arch/powerpc/include/asm/jump_label.h47
-rw-r--r--arch/powerpc/kernel/Makefile1
-rw-r--r--arch/powerpc/kernel/jump_label.c23
4 files changed, 72 insertions, 0 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 2729c6663d8..c15f2e61e4f 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -134,6 +134,7 @@ config PPC
select GENERIC_IRQ_SHOW_LEVEL
select HAVE_RCU_TABLE_FREE if SMP
select HAVE_SYSCALL_TRACEPOINTS
+ select HAVE_ARCH_JUMP_LABEL
config EARLY_PRINTK
bool
diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/asm/jump_label.h
new file mode 100644
index 00000000000..1f780b95c0f
--- /dev/null
+++ b/arch/powerpc/include/asm/jump_label.h
@@ -0,0 +1,47 @@
+#ifndef _ASM_POWERPC_JUMP_LABEL_H
+#define _ASM_POWERPC_JUMP_LABEL_H
+
+/*
+ * Copyright 2010 Michael Ellerman, IBM Corp.
+ *
+ * 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; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/types.h>
+
+#include <asm/feature-fixups.h>
+
+#define JUMP_ENTRY_TYPE stringify_in_c(FTR_ENTRY_LONG)
+#define JUMP_LABEL_NOP_SIZE 4
+
+static __always_inline bool arch_static_branch(struct jump_label_key *key)
+{
+ asm goto("1:\n\t"
+ "nop\n\t"
+ ".pushsection __jump_table, \"aw\"\n\t"
+ ".align 4\n\t"
+ JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t"
+ ".popsection \n\t"
+ : : "i" (key) : : l_yes);
+ return false;
+l_yes:
+ return true;
+}
+
+#ifdef CONFIG_PPC64
+typedef u64 jump_label_t;
+#else
+typedef u32 jump_label_t;
+#endif
+
+struct jump_entry {
+ jump_label_t code;
+ jump_label_t target;
+ jump_label_t key;
+ jump_label_t pad;
+};
+
+#endif /* _ASM_POWERPC_JUMP_LABEL_H */
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index e8b981897d4..ce4f7f17911 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -76,6 +76,7 @@ obj-$(CONFIG_MODULES) += module.o module_$(CONFIG_WORD_SIZE).o
obj-$(CONFIG_44x) += cpu_setup_44x.o
obj-$(CONFIG_PPC_FSL_BOOK3E) += cpu_setup_fsl_booke.o dbell.o
obj-$(CONFIG_PPC_BOOK3E_64) += dbell.o
+obj-$(CONFIG_JUMP_LABEL) += jump_label.o
extra-y := head_$(CONFIG_WORD_SIZE).o
extra-$(CONFIG_40x) := head_40x.o
diff --git a/arch/powerpc/kernel/jump_label.c b/arch/powerpc/kernel/jump_label.c
new file mode 100644
index 00000000000..368d158d665
--- /dev/null
+++ b/arch/powerpc/kernel/jump_label.c
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010 Michael Ellerman, IBM Corp.
+ *
+ * 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; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/jump_label.h>
+#include <asm/code-patching.h>
+
+void arch_jump_label_transform(struct jump_entry *entry,
+ enum jump_label_type type)
+{
+ u32 *addr = (u32 *)(unsigned long)entry->code;
+
+ if (type == JUMP_LABEL_ENABLE)
+ patch_branch(addr, entry->target, 0);
+ else
+ patch_instruction(addr, PPC_INST_NOP);
+}