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s390/ftrace: fix compile error if CONFIG_KPROBES is disabled 

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
hifive-unleashed-5.1
Heiko Carstens 2015-03-13 10:31:42 +01:00 committed by Martin Schwidefsky
parent 0a64815091
commit 20e76ee184
1 changed files with 45 additions and 16 deletions
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61
arch/s390/kernel/ftrace.c
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@ -57,6 +57,44 @@
unsigned long ftrace_plt;
static inline void ftrace_generate_orig_insn(struct ftrace_insn *insn)
{
#ifdef CC_USING_HOTPATCH
/* brcl 0,0 */
insn->opc = 0xc004;
insn->disp = 0;
#else
/* stg r14,8(r15) */
insn->opc = 0xe3e0;
insn->disp = 0xf0080024;
#endif
}
static inline int is_kprobe_on_ftrace(struct ftrace_insn *insn)
{
#ifdef CONFIG_KPROBES
if (insn->opc == BREAKPOINT_INSTRUCTION)
return 1;
#endif
return 0;
}
static inline void ftrace_generate_kprobe_nop_insn(struct ftrace_insn *insn)
{
#ifdef CONFIG_KPROBES
insn->opc = BREAKPOINT_INSTRUCTION;
insn->disp = KPROBE_ON_FTRACE_NOP;
#endif
}
static inline void ftrace_generate_kprobe_call_insn(struct ftrace_insn *insn)
{
#ifdef CONFIG_KPROBES
insn->opc = BREAKPOINT_INSTRUCTION;
insn->disp = KPROBE_ON_FTRACE_CALL;
#endif
}
int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
unsigned long addr)
{
@ -72,16 +110,9 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
return -EFAULT;
if (addr == MCOUNT_ADDR) {
/* Initial code replacement */
#ifdef CC_USING_HOTPATCH
/* We expect to see brcl 0,0 */
ftrace_generate_nop_insn(&orig);
#else
/* We expect to see stg r14,8(r15) */
orig.opc = 0xe3e0;
orig.disp = 0xf0080024;
#endif
ftrace_generate_orig_insn(&orig);
ftrace_generate_nop_insn(&new);
} else if (old.opc == BREAKPOINT_INSTRUCTION) {
} else if (is_kprobe_on_ftrace(&old)) {
/*
* If we find a breakpoint instruction, a kprobe has been
* placed at the beginning of the function. We write the
@ -89,9 +120,8 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
* bytes of the original instruction so that the kprobes
* handler can execute a nop, if it reaches this breakpoint.
*/
new.opc = orig.opc = BREAKPOINT_INSTRUCTION;
orig.disp = KPROBE_ON_FTRACE_CALL;
new.disp = KPROBE_ON_FTRACE_NOP;
ftrace_generate_kprobe_call_insn(&orig);
ftrace_generate_kprobe_nop_insn(&new);
} else {
/* Replace ftrace call with a nop. */
ftrace_generate_call_insn(&orig, rec->ip);
@ -111,7 +141,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
if (probe_kernel_read(&old, (void *) rec->ip, sizeof(old)))
return -EFAULT;
if (old.opc == BREAKPOINT_INSTRUCTION) {
if (is_kprobe_on_ftrace(&old)) {
/*
* If we find a breakpoint instruction, a kprobe has been
* placed at the beginning of the function. We write the
@ -119,9 +149,8 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
* bytes of the original instruction so that the kprobes
* handler can execute a brasl if it reaches this breakpoint.
*/
new.opc = orig.opc = BREAKPOINT_INSTRUCTION;
orig.disp = KPROBE_ON_FTRACE_NOP;
new.disp = KPROBE_ON_FTRACE_CALL;
ftrace_generate_kprobe_nop_insn(&orig);
ftrace_generate_kprobe_call_insn(&new);
} else {
/* Replace nop with an ftrace call. */
ftrace_generate_nop_insn(&orig);