| Date | Fri, 19 Jul 2013 10:03:28 +0100 | From | Will Deacon <> | Subject | Re: [PATCH v4 02/17] sched_clock: Use seqcount instead of rolling our own |
| |
On Fri, Jul 19, 2013 at 12:21:15AM +0100, Stephen Boyd wrote: > We're going to increase the cyc value to 64 bits in the near > future. Doing that is going to break the custom seqcount > implementation in the sched_clock code because 64 bit numbers > aren't guaranteed to be atomic. Replace the cyc_copy with a > seqcount to avoid this problem. > > Cc: Russell King <linux@arm.linux.org.uk> > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > --- > kernel/time/sched_clock.c | 27 ++++++++------------------- > 1 file changed, 8 insertions(+), 19 deletions(-)
Looks good to me. The current scheme would be very fiddly to extend to 64-bit values on 32-bit architectures without cheap atomic doubleword accesses.
Acked-by: Will Deacon <will.deacon@arm.com>
Will
|