Hi Stephen, On Sat, Apr 20, 2013 at 01:29:05AM +0100, Stephen Boyd wrote: > The arm architected system counter has at least 56 bits of > useable bits. Add support to ARM's sched_clock implementation for > counters with more than 32 bits so we can avoid the complexity of > dealing with wraparound on these devices while benefiting from > the irqtime accounting and suspend/resume handling that the ARM > sched_clock code already has. > > Signed-off-by: Stephen Boyd <sb...@codeaurora.org> > --- > > Maybe we need a union for the epoch_ns usage? > > arch/arm/include/asm/sched_clock.h | 2 + > arch/arm/kernel/sched_clock.c | 101 > +++++++++++++++++++++++++++---------- > 2 files changed, 77 insertions(+), 26 deletions(-) > > diff --git a/arch/arm/include/asm/sched_clock.h > b/arch/arm/include/asm/sched_clock.h > index 3d520dd..7fcd2ee 100644 > --- a/arch/arm/include/asm/sched_clock.h > +++ b/arch/arm/include/asm/sched_clock.h > @@ -13,4 +13,6 @@ extern void setup_sched_clock(u32 (*read)(void), int bits, > unsigned long rate); > > extern unsigned long long (*sched_clock_func)(void); > > +extern void setup_sched_clock_64(u64 (*read)(void), int bits, > + unsigned long rate);
Curious, but why do we need two setup_sched_clock functions, where the bits are passed as a parameter? Can't we just do the right thing if the clock claims to be more than 32 bits wide (and get rid of the BUG_ONs at the same time)? Will -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
