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Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kernel/ftrace.c42
1 files changed, 17 insertions, 25 deletions
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 3e3789c8f8e1..ef49517f6bb2 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -49,7 +49,7 @@ int ftrace_arch_code_modify_post_process(void)
union ftrace_code_union {
char code[MCOUNT_INSN_SIZE];
struct {
- unsigned char e8;
+ unsigned char op;
int offset;
} __attribute__((packed));
};
@@ -59,20 +59,23 @@ static int ftrace_calc_offset(long ip, long addr)
return (int)(addr - ip);
}
-static unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+static unsigned char *
+ftrace_text_replace(unsigned char op, unsigned long ip, unsigned long addr)
{
static union ftrace_code_union calc;
- calc.e8 = 0xe8;
+ calc.op = op;
calc.offset = ftrace_calc_offset(ip + MCOUNT_INSN_SIZE, addr);
- /*
- * No locking needed, this must be called via kstop_machine
- * which in essence is like running on a uniprocessor machine.
- */
return calc.code;
}
+static unsigned char *
+ftrace_call_replace(unsigned long ip, unsigned long addr)
+{
+ return ftrace_text_replace(0xe8, ip, addr);
+}
+
static inline int
within(unsigned long addr, unsigned long start, unsigned long end)
{
@@ -665,22 +668,6 @@ int __init ftrace_dyn_arch_init(void)
return 0;
}
-#if defined(CONFIG_X86_64) || defined(CONFIG_FUNCTION_GRAPH_TRACER)
-static unsigned char *ftrace_jmp_replace(unsigned long ip, unsigned long addr)
-{
- static union ftrace_code_union calc;
-
- /* Jmp not a call (ignore the .e8) */
- calc.e8 = 0xe9;
- calc.offset = ftrace_calc_offset(ip + MCOUNT_INSN_SIZE, addr);
-
- /*
- * ftrace external locks synchronize the access to the static variable.
- */
- return calc.code;
-}
-#endif
-
/* Currently only x86_64 supports dynamic trampolines */
#ifdef CONFIG_X86_64
@@ -892,8 +879,8 @@ static void *addr_from_call(void *ptr)
return NULL;
/* Make sure this is a call */
- if (WARN_ON_ONCE(calc.e8 != 0xe8)) {
- pr_warn("Expected e8, got %x\n", calc.e8);
+ if (WARN_ON_ONCE(calc.op != 0xe8)) {
+ pr_warn("Expected e8, got %x\n", calc.op);
return NULL;
}
@@ -964,6 +951,11 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops)
#ifdef CONFIG_DYNAMIC_FTRACE
extern void ftrace_graph_call(void);
+static unsigned char *ftrace_jmp_replace(unsigned long ip, unsigned long addr)
+{
+ return ftrace_text_replace(0xe9, ip, addr);
+}
+
static int ftrace_mod_jmp(unsigned long ip, void *func)
{
unsigned char *new;