From: Masami Hiramatsu Date: Wed, 30 Jan 2008 12:32:02 +0000 (+0100) Subject: x86: move deeply indented code to reenter_kprobe X-Git-Tag: v2.6.25-rc1~1143^2~485 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=59e87cdcd268daa85c0732e147c59e0c1bacd704;p=linux-2.6 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 Cc: Ananth N Mavinakayanahalli Cc: Jim Keniston Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c index 7dd918633c..4e33329ce8 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