Move ftrace over to using the generic x86 text_poke functions; this
avoids having a second/different copy of that code around.
Cc: Daniel Bristot de Oliveira
Cc: Steven Rostedt
Signed-off-by: Peter Zijlstra (Intel)
---
arch/x86/include/asm/ftrace.h |2
arch/x86/kernel/ftrace.c | 571 +++---
arch/x86/kernel/traps.c |9
3 files changed, 51 insertions(+), 531 deletions(-)
--- a/arch/x86/include/asm/ftrace.h
+++ b/arch/x86/include/asm/ftrace.h
@@ -35,8 +35,6 @@ struct dyn_arch_ftrace {
/* No extra data needed for x86 */
};
-int ftrace_int3_handler(struct pt_regs *regs);
-
#define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR
#endif /* CONFIG_DYNAMIC_FTRACE */
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -43,16 +43,17 @@ int ftrace_arch_code_modify_prepare(void
* ftrace has it set to "read/write".
*/
mutex_lock(_mutex);
- set_kernel_text_rw();
- set_all_modules_text_rw();
+ WARN_ON_ONCE(tp_vec_nr);
return 0;
}
int ftrace_arch_code_modify_post_process(void)
__releases(_mutex)
{
- set_all_modules_text_ro();
- set_kernel_text_ro();
+ if (tp_vec_nr) {
+ text_poke_bp_batch(tp_vec, tp_vec_nr);
+ tp_vec_nr = 0;
+ }
mutex_unlock(_mutex);
return 0;
}
@@ -60,67 +61,36 @@ int ftrace_arch_code_modify_post_process
union ftrace_code_union {
char code[MCOUNT_INSN_SIZE];
struct {
- unsigned char op;
+ char op;
int offset;
} __attribute__((packed));
};
-static int ftrace_calc_offset(long ip, long addr)
-{
- return (int)(addr - ip);
-}
-
-static unsigned char *
-ftrace_text_replace(unsigned char op, unsigned long ip, unsigned long addr)
+static char *ftrace_text_replace(char op, unsigned long ip, unsigned long addr)
{
static union ftrace_code_union calc;
- calc.op = op;
- calc.offset = ftrace_calc_offset(ip + MCOUNT_INSN_SIZE, addr);
+ calc.op = op;
+ calc.offset = (int)(addr - (ip + MCOUNT_INSN_SIZE));
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)
+static char *ftrace_nop_replace(void)
{
- return addr >= start && addr < end;
-}
-
-static unsigned long text_ip_addr(unsigned long ip)
-{
- /*
-* On x86_64, kernel text mappings are mapped read-only, so we use
-* the kernel identity mapping instead of the kernel text mapping
-* to modify the kernel text.
-*
-* For 32bit kernels, these mappings are same and we can use
-* kernel identity mapping to modify code.
-*/
- if (within(ip, (unsigned long)_text, (unsigned long)_etext))
- ip = (unsigned long)__va(__pa_symbol(ip));
-
- return ip;
+ return ideal_nops[NOP_ATOMIC5];
}
-static const unsigned char *ftrace_nop_replace(void)
+static char *ftrace_call_replace(unsigned long ip, unsigned long addr)
{
- return ideal_nops[NOP_ATOMIC5];
+ return ftrace_text_replace(CALL_INSN_OPCODE, ip, addr);
}
-static int
-ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code,
- unsigned const char *new_code)
+static int;
+ftrace_modify_code_direct(unsigned long ip, const char *old_code,
+ const char *new_code)
{
- unsigned char replaced[MCOUNT_INSN_SIZE];
-
- ftrace_expected = old_code;
+ char cur_code[MCOUNT_INSN_SIZE];
/*
* Note:
@@ -129,31 +99,23 @@ ftrace_modify_code_direct(unsigned long
* Carefully read and modify the code with probe_kernel_*(), and make
* sure what we read is what we expected it to be before modifying it.
*/
-
/* read the text we want to modify */
- if (probe_kernel_read(replaced, (void *)ip, MCOUNT_INSN_SIZE))
+ if (probe_kernel_read(cur_code, (void *)ip, MCOUNT_INSN_SIZE))
return -EFAULT;
/* Make sure it is what we expect it to be */
- if (memcmp(replaced, old_code, MCOUNT_INSN_SIZE) != 0)
+ if (memcmp(cur_code, old_code, MCOUNT_INSN_SIZE) != 0)
return -EINVAL;
- ip = text_ip_addr(ip);
-
/* replace the text with the new text */
- if (probe_kernel_write((void *)ip, new_code, MCOUNT_INSN_SIZE))
- return -EPERM;
-
- sync_core();
-
+ text_poke_early((void *)ip, new_code, MCOUNT_INSN_SIZE);
return 0;
}
-int ftrace_make_nop(struct module *mod,
- struct dyn_ftrace *rec, unsigned long addr)
+int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long
addr)
{
- unsigned const char *new, *old;
unsigned long
