[PATCH] Make the kernel NTP code hand 64-bit *unsigned* values to do_div() [try #3]

[PATCH] Make the kernel NTP code hand 64-bit *unsigned* values to do_div() [try #3]

[David Howells]

From: David Howells <dhowells@redhat.com>

The kernel NTP code shouldn't hand 64-bit *signed* values to do_div().  Make it
instead hand 64-bit unsigned values.  This gets rid of a couple of warnings.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 kernel/time/ntp.c |   12 +++++++-----
 1 files changed, 7 insertions(+), 5 deletions(-)


diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index c88b591..d4bca92 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -342,14 +342,16 @@ int do_adjtimex(struct timex *txc)
 		    freq_adj = shift_right(freq_adj, time_constant * 2 +
 					   (SHIFT_PLL + 2) * 2 - SHIFT_NSEC);
 		    if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) {
+			u64 utemp64;
 			temp64 = time_offset << (SHIFT_NSEC - SHIFT_FLL);
 			if (time_offset < 0) {
-			    temp64 = -temp64;
-			    do_div(temp64, mtemp);
-			    freq_adj -= temp64;
+			    utemp64 = -temp64;
+			    do_div(utemp64, mtemp);
+			    freq_adj -= utemp64;
 			} else {
-			    do_div(temp64, mtemp);
-			    freq_adj += temp64;
+			    utemp64 = temp64;
+			    do_div(utemp64, mtemp);
+			    freq_adj += utemp64;
 			}
 		    }
 		    freq_adj += time_freq;

Re: [PATCH] Make the kernel NTP code hand 64-bit *unsigned* values to do_div() [try #3]

[Andrew Morton]

On Thu, 21 Feb 2008 16:50:35 +0000 David Howells <dhowells@redhat.com> wrote:

> From: David Howells <dhowells@redhat.com>
> 
> The kernel NTP code shouldn't hand 64-bit *signed* values to do_div().  Make it
> instead hand 64-bit unsigned values.  This gets rid of a couple of warnings.

On certain architectures.  It would have bene nice to mention what those
architectures are, and to quote the warnings.  Next time, please ;)

> Signed-off-by: David Howells <dhowells@redhat.com>
> ---
> 
>  kernel/time/ntp.c |   12 +++++++-----

Thomas, do you consider ntp to fall under git-hrt?

Re: [PATCH] Make the kernel NTP code hand 64-bit *unsigned* values to do_div() [try #3]

[Thomas Gleixner]

On Sat, 23 Feb 2008, Andrew Morton wrote:

> On Thu, 21 Feb 2008 16:50:35 +0000 David Howells <dhowells@redhat.com> wrote:
> 
> > From: David Howells <dhowells@redhat.com>
> > 
> > The kernel NTP code shouldn't hand 64-bit *signed* values to do_div().  Make it
> > instead hand 64-bit unsigned values.  This gets rid of a couple of warnings.
> 
> On certain architectures.  It would have bene nice to mention what those
> architectures are, and to quote the warnings.  Next time, please ;)
> 
> > Signed-off-by: David Howells <dhowells@redhat.com>
> > ---
> > 
> >  kernel/time/ntp.c |   12 +++++++-----
> 
> Thomas, do you consider ntp to fall under git-hrt?

I'll pick it up.

Thanks,

	tglx

Re: [PATCH] Make the kernel NTP code hand 64-bit *unsigned* values to do_div() [try #3]

[Andrew Morton]

On Sat, 23 Feb 2008 22:01:55 +0100 (CET) Thomas Gleixner <tglx@linutronix.de> wrote:

> On Sat, 23 Feb 2008, Andrew Morton wrote:
> 
> > On Thu, 21 Feb 2008 16:50:35 +0000 David Howells <dhowells@redhat.com> wrote:
> > 
> > > From: David Howells <dhowells@redhat.com>
> > > 
> > > The kernel NTP code shouldn't hand 64-bit *signed* values to do_div().  Make it
> > > instead hand 64-bit unsigned values.  This gets rid of a couple of warnings.
> > 
> > On certain architectures.  It would have bene nice to mention what those
> > architectures are, and to quote the warnings.  Next time, please ;)
> > 
> > > Signed-off-by: David Howells <dhowells@redhat.com>
> > > ---
> > > 
> > >  kernel/time/ntp.c |   12 +++++++-----
> > 
> > Thomas, do you consider ntp to fall under git-hrt?
> 
> I'll pick it up.
> 


OK.  And this is still
git+ssh://master.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt.git#mm,
yes?

Can we please define the scope of that tree?

Please review

fix-shadowed-variables-in-kernel-posix-cpu-timersc.patch
timers-simplify-lockdep-stuff.patch
hrtimers-simplify-lockdep-stuff.patch
kill-double_spin_lock.patch
ntp-make-the-kernel-ntp-code-hand-64-bit-unsigned-values-to-do_div.patch

from http://userweb.kernel.org/~akpm/mmotm/broken-out/.  I think they're
all probably git-hrt material.

Can we get that tree into linux-next too please?

Re: [PATCH] Make the kernel NTP code hand 64-bit *unsigned* values to do_div() [try #3]

[Thomas Gleixner]

On Sat, 23 Feb 2008, Andrew Morton wrote:
> > > Thomas, do you consider ntp to fall under git-hrt?
> > 
> > I'll pick it up.
> > 
> OK.  And this is still
> git+ssh://master.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt.git#mm,
> yes?

Yes
 
> Can we please define the scope of that tree?

Primary scope is hrtimer, posixtimer, clockevents & Co.

In the last month I fed a lot of timekeeping/ntp stuff via -hrt as
well. If there is no objection, I'm happy to provide the sink for
those.

> Please review
> 
> fix-shadowed-variables-in-kernel-posix-cpu-timersc.patch
> timers-simplify-lockdep-stuff.patch
> hrtimers-simplify-lockdep-stuff.patch
> kill-double_spin_lock.patch
> ntp-make-the-kernel-ntp-code-hand-64-bit-unsigned-values-to-do_div.patch
> 
> from http://userweb.kernel.org/~akpm/mmotm/broken-out/.  I think they're
> all probably git-hrt material.

Will do tomorrow, when I'm more awake.

> Can we get that tree into linux-next too please?

Will contact Stephen.

Thanks,

	tglx