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authorPekka Enberg <penberg@kernel.org>2010-10-24 19:57:05 +0300
committerPekka Enberg <penberg@kernel.org>2010-10-24 19:57:05 +0300
commit6d4121f6c20a0e86231d52f535f1c82423b3326f (patch)
tree5c235cac699ca86b504850aa663ddadde0455a61 /arch/x86/kernel/jump_label.c
parent92a5bbc11ff2442a54b2f1d313088c245828ef4e (diff)
parent35da7a307c535f9c2929cae277f3df425c9f9b1e (diff)
Merge branch 'master' into for-linus
Conflicts: include/linux/percpu.h mm/percpu.c
Diffstat (limited to 'arch/x86/kernel/jump_label.c')
-rw-r--r--arch/x86/kernel/jump_label.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
new file mode 100644
index 00000000000..961b6b30ba9
--- /dev/null
+++ b/arch/x86/kernel/jump_label.c
@@ -0,0 +1,50 @@
+/*
+ * jump label x86 support
+ *
+ * Copyright (C) 2009 Jason Baron <jbaron@redhat.com>
+ *
+ */
+#include <linux/jump_label.h>
+#include <linux/memory.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/jhash.h>
+#include <linux/cpu.h>
+#include <asm/kprobes.h>
+#include <asm/alternative.h>
+
+#ifdef HAVE_JUMP_LABEL
+
+union jump_code_union {
+ char code[JUMP_LABEL_NOP_SIZE];
+ struct {
+ char jump;
+ int offset;
+ } __attribute__((packed));
+};
+
+void arch_jump_label_transform(struct jump_entry *entry,
+ enum jump_label_type type)
+{
+ union jump_code_union code;
+
+ if (type == JUMP_LABEL_ENABLE) {
+ code.jump = 0xe9;
+ code.offset = entry->target -
+ (entry->code + JUMP_LABEL_NOP_SIZE);
+ } else
+ memcpy(&code, ideal_nop5, JUMP_LABEL_NOP_SIZE);
+ get_online_cpus();
+ mutex_lock(&text_mutex);
+ text_poke_smp((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE);
+ mutex_unlock(&text_mutex);
+ put_online_cpus();
+}
+
+void arch_jump_label_text_poke_early(jump_label_t addr)
+{
+ text_poke_early((void *)addr, ideal_nop5, JUMP_LABEL_NOP_SIZE);
+}
+
+#endif