Preemption-safe kprobe-booster(Re: [PATCH]kprobe booster for IA64)

[Masami Hiramatsu]

Hi, Anil

Keshavamurthy Anil S wrote:
> --Comment here please 
>  /* Booster probe is not support for preemptable kernel */
>> +#ifdef CONFIG_PREEMPT
>    ^^^^^^ Should be #ifndef

That's for sure, I fixed it.

>> +	if (p->ainsn.boostable == 1 && !p->post_handler){
>>  		/* Boost up -- we can execute copied instructions directly */
>>  		reset_current_kprobe();
>>  		regs->eip = (unsigned long)p->ainsn.insn;
>>  		preempt_enable_no_resched();
>>  		return 1;
>>  	}
>> +#endif
>>  	prepare_singlestep(p, regs);
>>  	kcb->kprobe_status = KPROBE_HIT_SS;
>>  	return 1;
> 
> Also you may want to do the same thing for kretprobe booster.

I think the kretprobe booster is not affected by kernel preemption.
Because all codes on the execution path of kretprobe-booster
are the static assembly codes. These codes are never removed.

> 
> Thanks,
> Anil
> 
> 

Thanks,

-- 
Masami HIRAMATSU
2nd Research Dept.
Hitachi, Ltd., Systems Development Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com