Re: [PATCH 1/1] kernel/workqueue.c: pr_warning/pr_warn & printk/pr_info

[Joe Perches <joe@perches.com>]

On Mon, 2014-05-12 at 19:56 +0200, Fabian Frederick wrote:
> Cc: Tejun Heo <tj@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Fabian Frederick <fabf@skynet.be>
> ---
>  kernel/workqueue.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index 0ee63af..6824afc 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -4098,8 +4098,8 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
>  	/* create a new pwq */
>  	pwq = alloc_unbound_pwq(wq, target_attrs);
>  	if (!pwq) {
> -		pr_warning("workqueue: allocation failed while updating NUMA affinity of \"%s\"\n",
> -			   wq->name);
> +		pr_warn("workqueue: allocation failed while updating NUMA affinity of \"%s\"\n",
> +			wq->name);
>  		goto out_unlock;
>  	}
>  
> @@ -4548,7 +4548,7 @@ void print_worker_info(const char *log_lvl, struct task_struct *task)
>  		probe_kernel_read(desc, worker->desc, sizeof(desc) - 1);
>  
>  	if (fn || name[0] || desc[0]) {
> -		printk("%sWorkqueue: %s %pf", log_lvl, name, fn);
> +		pr_info("%sWorkqueue: %s %pf", log_lvl, name, fn);

Not correct.

log_lvl already emits the appropriate level
and this overrides it with KERN_INFO.

The output will now be incorrect emitting
at KERN_INFO followed by an SOH and the
desired log level.

>  		if (desc[0])
>  			pr_cont(" (%s)", desc);
>  		pr_cont("\n");

Trivially, it likely would be a bit better to avoid
any possible output message interleaving by using:

	if (fn || name[0] || desc[0]) {
		if (desc[0])
			printk("%sWorkqueue: %s %pf (%s)\n",
			       log_lvl, name, fn, desc);
		else
			printk("%sWorkqueue: %s %pf\n",
			       log_lvl, name, fn);
	}