Re: [Dle-develop] [RFC][PATCH -next] make pstore/kmsg_dump run after stopping other cpus in panic path

[Seiji A. <sei...@hd...>]

Hi,

Thank you for giving me a comment.

>I have a stupid question: since you have serialized the process procedure via
>smp_send_stop, why still using spin_lock_xxx? Maybe preempt_disable/enable is
>enough?


I added spin_lock_init() in panic path for sharing code with other triggers 
such as oops/reboot/emergency_restart because they still need spin_locks.

Do you suggest following code?

<snip>
If(!panic)
	spin_lock_irqsave();

     .
     .
If(!panic)
	spin_unlock_restore();
<snip>

I don't stick to current patch.
So I will resend a patch above if you request.

Regarding as preempt_disable/enable, we don't need to call them in panic path because they are
called at the beginning of panic().

	<snip>
	60 NORET_TYPE void panic(const char * fmt, ...)  
	61 {  
	62         static char buf[1024];  
	63         va_list args;  
	64         long i, i_next = 0;  
	65         int state = 0;  
	66   
	67         /*  
	68          * It's possible to come here directly from a panic-assertion and  
	69          * not have preempt disabled. Some functions called from here want  
	70          * preempt to be disabled. No point enabling it later though...  
	71          */  
	72         preempt_disable();
	<snip>

Seiji