On Fri, 2007-08-24 at 08:46 -0400, Bob Picco wrote: > john stultz wrote: [Thu Aug 23 2007, 05:41:45PM EDT] > > On Thu, 2007-08-23 at 14:05 -0700, john stultz wrote: > > > On Thu, 2007-08-23 at 13:41 -0700, Luck, Tony wrote: > > > > > I have a double "hpet" entry in "available_clocksource": > > > > > $ cat > > > > > /sys/devices/system/clocksource/clocksource0/available_clocksource > > > > > tsc hpet hpet acpi_pm jiffies > > > > > > > > Oops. If seems that both drivers/char/hpet.c and > > > > arch/x86_64/kernel/hpet.c > > > > both register a clocksource named "hpet". Probably a result of bringing > > > > back to life a long lost patch, and having someone else (John Stultz, > > > > according > > > > to git blame) make a similar change to a different file in the > > > > intervening > > > > time. > > > > > > > > Presumably the thing to do would be merge the x86_64 specific version > > > > into the drivers/char/hpet.c version? > > > > > > Ugh. Yea. i386 has an hpet clocksource as well. We should kill the > > > duplication, but at the moment I'm not comfortable that the > > > driver/char/hpet.c is ok to be used for i386/x86_64 (Bob: Do you know > > > why the shift value is only 10?). > > > > > > > > > I'm a little surprised by this, as the clocksource code use to prevent > > > duplicate named clocksources from being registered, so I'm not sure how > > > that check got dropped. Also I'm not quite sure I see where the hard > > > freeze is coming from. > > > > > > My initial reaction would be to either ifdef ia64 implementation in > > > drivers/char/hpet.c or move the code under the ia64 arch dir until it is > > > really usable by all arches. > > > > Here is a possible quick fix. I'm open to other approaches, but I also > > want to avoid too much churn before 2.6.23 goes out. > > > > Paolo, could you verify this fixes the issue for you? > > > > thanks > > -john > > > [snip] > > I saw what was missed by me in my brief examination of this last night. > The platform registers the hpet clocksource too. > > Instead of adding the config flag to hpet driver, how about the patch > below? Since you already check for duplication by address then adding > a check for by name too seems okay to me. > > bob > > > Prevent duplicate names being registered with clocksource. This also > eliminates the duplication of hpet clock registration when the arch > uses the hpet timer and the hpet driver does too. The patch was > compile and link tested.
Yea. While I'm still not completely comfortable leaving this up to boot order alone (the ia64 hpet clocksource is clearly causing issues on x86_64), I think this patch is something we need as well. > > Signed-off-by: Bob Picco <[EMAIL PROTECTED]> Acked-by: John Stultz <[EMAIL PROTECTED]> > kernel/time/clocksource.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: linux-2.6.23-rc3/kernel/time/clocksource.c > =================================================================== > --- linux-2.6.23-rc3.orig/kernel/time/clocksource.c 2007-08-23 > 16:44:03.000000000 -0400 > +++ linux-2.6.23-rc3/kernel/time/clocksource.c 2007-08-24 > 08:36:41.000000000 -0400 > @@ -281,7 +281,7 @@ static int clocksource_enqueue(struct cl > struct clocksource *cs; > > cs = list_entry(tmp, struct clocksource, list); > - if (cs == c) > + if (cs == c || !strcmp(cs->name, c->name)) > return -EBUSY; > /* Keep track of the place, where to insert */ > if (cs->rating >= c->rating) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
