Re: [1/4] rcu: Detect uses of rcu read side in extended quiescent states

[Milton Miller <miltonm@bga.com>]

On Mon, 06 Jun 2011 about 03:10:55 -0000, Frederic Weisbecker wrote:
> @@ -3994,8 +3995,13 @@ void lockdep_rcu_dereference(const char *file, const int line)
>  	printk("\n===================================================\n");
>  	printk(  "[ INFO: suspicious rcu_dereference_check() usage. ]\n");
>  	printk(  "---------------------------------------------------\n");
> -	printk("%s:%d invoked rcu_dereference_check() without protection!\n",
> -			file, line);
> +	printk("%s:%d invoked rcu_dereference_check() ", file, line);
> +
> +	if (type == RCU_WARN_UNPROTECTED)
> +		printk("without protection!\n");
> +	else if (type == RCU_WARN_EXT_QS)
> +		printk("while in RCU extended quiescent state!\n");
> +
>  	printk("\nother info that might help us debug this:\n\n");
>  	printk("\nrcu_scheduler_active = %d, debug_locks = %d\n", rcu_scheduler_active, debug_locks);
>  	lockdep_print_held_locks(curr);

Can we keep the above in one printk?   That way the printing is
guaranteed to come out on one line.  Probably the easiest way would
be add char *why = "" then assign a string based on the current
conditions.  Do all of that before the first printk which gets the
a %s added.

Thanks,
milton