Re: [PATCH 09/11] drivers/scsi: Convert #ifdef DEBUG printk(KERN_DEBUG to pr_debug(

Joe Perches
2009-05-15T19:05:06Z

On Fri, 2009-05-15 at 18:56 +0000, James Bottomley wrote:
> On Fri, 2009-05-15 at 10:59 -0700, Joe Perches wrote:
> > diff --git a/drivers/scsi/aha1542.c b/drivers/scsi/aha1542.c
> > index 8059494..29d5118 100644
> > --- a/drivers/scsi/aha1542.c
> > +++ b/drivers/scsi/aha1542.c
> > @@ -509,9 +509,7 @@ static void aha1542_intr_handle(struct Scsi_Host *shost)
> > if (mbistatus == 3)
> > continue; /* Aborted command not found */
> >
> > -#ifdef DEBUG
> > - printk(KERN_DEBUG "...done %d %d\n", mbo, mbi);
> > -#endif
> > + pr_debug("...done %d %d\n", mbo, mbi);
>
> This one looks dangerous ... that's a per trigger printk from interrupt
> context. That's a lot of stuff to bung in the log buffer for a normal
> operating case (which is pretty interrupt heavy). What does this do to
> system responsiveness?

The normal operating case is not to define DEBUG.

Hmm, if CONFIG_DYNAMIC_DEBUG is enabled, it is a functional change.
Maybe the changes should be to pr_devel?