x86: move deeply indented code to reenter_kprobe

Move some deeply indented code related to re-entrance processing
from kprobe_handler() to reenter_kprobe().

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 23 insertions, 23 deletions

diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 7dd918633c30..4e33329ce8a3 100644
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -432,14 +432,32 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
  * within the handler. We save the original kprobes variables and just single
  * step on the instruction of the new probe without calling any user handlers.
  */
-static void __kprobes reenter_kprobe(struct kprobe *p, struct pt_regs *regs,
-                                     struct kprobe_ctlblk *kcb)
+static int __kprobes reenter_kprobe(struct kprobe *p, struct pt_regs *regs,
+                                    struct kprobe_ctlblk *kcb)
 {
+        if (kcb->kprobe_status == KPROBE_HIT_SS &&
+            *p->ainsn.insn == BREAKPOINT_INSTRUCTION) {
+                regs->flags &= ~X86_EFLAGS_TF;
+                regs->flags |= kcb->kprobe_saved_flags;
+                return 0;
+#ifdef CONFIG_X86_64
+        } else if (kcb->kprobe_status == KPROBE_HIT_SSDONE) {
+                /* TODO: Provide re-entrancy from post_kprobes_handler() and
+                 * avoid exception stack corruption while single-stepping on
+                 * the instruction of the new probe.
+                 */
+                arch_disarm_kprobe(p);
+                regs->ip = (unsigned long)p->addr;
+                reset_current_kprobe();
+                return 1;
+#endif
+        }
         save_previous_kprobe(kcb);
         set_current_kprobe(p, regs, kcb);
         kprobes_inc_nmissed_count(p);
         prepare_singlestep(p, regs);
         kcb->kprobe_status = KPROBE_REENTER;
+        return 1;
 }
 
 /*
@@ -466,27 +484,9 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
         if (kprobe_running()) {
                 p = get_kprobe(addr);
                 if (p) {
-                        if (kcb->kprobe_status == KPROBE_HIT_SS &&
-                                *p->ainsn.insn == BREAKPOINT_INSTRUCTION) {
-                                regs->flags &= ~X86_EFLAGS_TF;
-                                regs->flags |= kcb->kprobe_saved_flags;
-                                goto no_kprobe;
-#ifdef CONFIG_X86_64
-                        } else if (kcb->kprobe_status == KPROBE_HIT_SSDONE) {
-                                /* TODO: Provide re-entrancy from
-                                 * post_kprobes_handler() and avoid exception
-                                 * stack corruption while single-stepping on
-                                 * the instruction of the new probe.
-                                 */
-                                arch_disarm_kprobe(p);
-                                regs->ip = (unsigned long)p->addr;
-                                reset_current_kprobe();
-                                ret = 1;
-                                goto no_kprobe;
-#endif
-                        }
-                        reenter_kprobe(p, regs, kcb);
-                        return 1;
+                        ret = reenter_kprobe(p, regs, kcb);
+                        if (kcb->kprobe_status == KPROBE_REENTER)
+                                return 1;
                 } else {
                         if (*addr != BREAKPOINT_INSTRUCTION) {
                         /* The breakpoint instruction was removed by