[PATCH] ide_tape: convert jiffies with jiffies_to_msecs

[PATCH] ide_tape: convert jiffies with jiffies_to_msecs

[Nicholas Mc Guire]

Use jiffies_to_msecs for converting jiffies as it handles all of the corner
cases reliably and also helps readability. The printk format is fixed up 
as jiffies_to_msecs returns unsigned int not unsigned long.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
---

Note that this patch will give a checkpatch warning due to "quoted string 
split across lines" but thats not related to this change - not sure if this
should be fixed - looks intentional to me.

This was only compile tested with x86_64_defconfig + CONFIG_IDE=m,
CONFIG_BLK_DEV_IDETAPE=m

Patch is against 4.0-rc1 (localversion-next is -next-20150303)

 drivers/ide/ide-tape.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index 1793aea..d9ce376 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -1793,11 +1793,11 @@ static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
 	tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
 					 IDETAPE_DSC_RW_MAX);
 	printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
-		"%lums tDSC%s\n",
+		"%dms tDSC%s\n",
 		drive->name, tape->name, *(u16 *)&tape->caps[14],
 		(*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
 		tape->buffer_size / 1024,
-		tape->best_dsc_rw_freq * 1000 / HZ,
+		jiffies_to_msecs(tape->best_dsc_rw_freq),
 		(drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
 
 	ide_proc_register_driver(drive, tape->driver);
-- 
1.7.10.4

Re: [PATCH] ide_tape: convert jiffies with jiffies_to_msecs

[Joe Perches]

On Tue, 2015-03-03 at 05:23 -0500, Nicholas Mc Guire wrote:
> Use jiffies_to_msecs for converting jiffies as it handles all of the corner
> cases reliably and also helps readability. The printk format is fixed up 
> as jiffies_to_msecs returns unsigned int not unsigned long.

Then ideally you'd use %u not %d.

> Note that this patch will give a checkpatch warning due to "quoted string 
> split across lines" but thats not related to this change - not sure if this
> should be fixed - looks intentional to me.

It's not.  It'd be better coalesced.

> diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
[]
> @@ -1793,11 +1793,11 @@ static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
>  	tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
>  					 IDETAPE_DSC_RW_MAX);
>  	printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
> -		"%lums tDSC%s\n",
> +		"%dms tDSC%s\n",
>  		drive->name, tape->name, *(u16 *)&tape->caps[14],
>  		(*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
>  		tape->buffer_size / 1024,
> -		tape->best_dsc_rw_freq * 1000 / HZ,
> +		jiffies_to_msecs(tape->best_dsc_rw_freq),
>  		(drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");

Re: [PATCH] ide_tape: convert jiffies with jiffies_to_msecs

[Nicholas Mc Guire]

On Tue, 03 Mar 2015, Joe Perches wrote:

> On Tue, 2015-03-03 at 05:23 -0500, Nicholas Mc Guire wrote:
> > Use jiffies_to_msecs for converting jiffies as it handles all of the corner
> > cases reliably and also helps readability. The printk format is fixed up 
> > as jiffies_to_msecs returns unsigned int not unsigned long.
> 
> Then ideally you'd use %u not %d.
>

ok - was not clear about that as there are very many cases wher u32 
is printed with %d and compilers seem to be happy with this -
gcc (Debian 4.7.2-5) 4.7.2 in my case.
will fix that up and repost.
 
> > Note that this patch will give a checkpatch warning due to "quoted string 
> > split across lines" but thats not related to this change - not sure if this
> > should be fixed - looks intentional to me.
> 
> It's not.  It'd be better coalesced.

well it did seem quite systematic in this file, aside from it also needing
to move over the pr_* so thats going to need a few seperate cleanups.

> 
> > diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
> []
> > @@ -1793,11 +1793,11 @@ static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
> >  	tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
> >  					 IDETAPE_DSC_RW_MAX);
> >  	printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
> > -		"%lums tDSC%s\n",
> > +		"%dms tDSC%s\n",
> >  		drive->name, tape->name, *(u16 *)&tape->caps[14],
> >  		(*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
> >  		tape->buffer_size / 1024,
> > -		tape->best_dsc_rw_freq * 1000 / HZ,
> > +		jiffies_to_msecs(tape->best_dsc_rw_freq),
> >  		(drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
> 
>
thanks for the review notes!

thx!
hofrat 

Re: [PATCH] ide_tape: convert jiffies with jiffies_to_msecs

[Joe Perches]

On Tue, 2015-03-03 at 11:57 +0100, Nicholas Mc Guire wrote:
> On Tue, 03 Mar 2015, Joe Perches wrote:
> > On Tue, 2015-03-03 at 05:23 -0500, Nicholas Mc Guire wrote:
> > > Note that this patch will give a checkpatch warning due to "quoted string 
> > > split across lines" but thats not related to this change - not sure if this
> > > should be fixed - looks intentional to me.
> > 
> > It's not.  It'd be better coalesced.
> 
> well it did seem quite systematic in this file, aside from it also needing
> to move over the pr_* so thats going to need a few seperate cleanups.

Sure, no worries, whenever/ifever.

I'm pretty sure there aren't many active users
of ide-tape devices.

Re: [PATCH] ide_tape: convert jiffies with jiffies_to_msecs

[Nicholas Mc Guire]

On Tue, 03 Mar 2015, Joe Perches wrote:

> On Tue, 2015-03-03 at 11:57 +0100, Nicholas Mc Guire wrote:
> > On Tue, 03 Mar 2015, Joe Perches wrote:
> > > On Tue, 2015-03-03 at 05:23 -0500, Nicholas Mc Guire wrote:
> > > > Note that this patch will give a checkpatch warning due to "quoted string 
> > > > split across lines" but thats not related to this change - not sure if this
> > > > should be fixed - looks intentional to me.
> > > 
> > > It's not.  It'd be better coalesced.
> > 
> > well it did seem quite systematic in this file, aside from it also needing
> > to move over the pr_* so thats going to need a few seperate cleanups.
> 
> Sure, no worries, whenever/ifever.
> 
> I'm pretty sure there aren't many active users
> of ide-tape devices.
>
Im sure thats true - the motivation for cleanups though is that what ever
stays in old drivers - even if hardly in use- gets copied into new drivers
at some point...

thx!
hofrat