Re: [PATCH 1/4] sd: fix cache flushing message

[Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>]

On Wednesday 29 April 2009 22:22:51 Jeff Garzik wrote:
> James Bottomley wrote:
> > On Wed, 2009-04-29 at 22:06 +0200, Bartlomiej Zolnierkiewicz wrote:
> >> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> >> ---
> >> some minor sd.c fixups against linux-next
> >>
> >>  drivers/scsi/sd.c |    4 ++--
> >>  1 file changed, 2 insertions(+), 2 deletions(-)
> >>
> >> Index: b/drivers/scsi/sd.c
> >> ===================================================================
> >> --- a/drivers/scsi/sd.c
> >> +++ b/drivers/scsi/sd.c
> >> @@ -2140,7 +2140,7 @@ static void sd_shutdown(struct device *d
> >>  		return;         /* this can happen */
> >>  
> >>  	if (sdkp->WCE) {
> >> -		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
> >> +		sd_printk(KERN_NOTICE, sdkp, "Synchronizing disk cache\n");
> >>  		sd_sync_cache(sdkp);
> >>  	}
> >>  
> >> @@ -2161,7 +2161,7 @@ static int sd_suspend(struct device *dev
> >>  		return 0;	/* this can happen */
> >>  
> >>  	if (sdkp->WCE) {
> >> -		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
> >> +		sd_printk(KERN_NOTICE, sdkp, "Synchronizing disk cache\n");
> >>  		ret = sd_sync_cache(sdkp);
> >>  		if (ret)
> >>  			goto done;
> > 
> > So you want it to say 
> > 
> > sda: synchronizing disk cache
> > 
> > instead of
> > 
> > sda: synchronizing SCSI cache
> > 
> > I don't really see that buying us anything in terms of clarity.  What's
> > the actual problem it solves?

Inconsistent kernel messages:

	if (sdkp->WCE) {
		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
		sd_sync_cache(sdkp);
	}

	if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
		sd_start_stop_device(sdkp, 0);
	}

> Indeed.
> 
> And we can argue for weeks about English text, too.  Non-disk devices 

Or we can just apply the patch and go back with the program.

> like SSDs have caches too, so I'd say "SCSI cache" is more accurate than 
> "disk cache".  But maybe "SCSI writeback cache" would be even better.

Could you please explain me what *SCSI* cache is?

Does ATA disks have *SCSI* cache (whatever it is)?

Please also note that sd.c uses "disk" all over the place.

Thanks,
Bart