Re: [PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread john stultz
On Tue, 2007-03-20 at 11:04 -0700, Daniel Walker wrote: > On Tue, 2007-03-20 at 10:58 -0700, john stultz wrote: > > > > /* timekeeping specific data, ignore */ > > > - cycle_t cycle_last, cycle_interval; > > > - u64 xtime_nsec, xtime_interval; > > > + cycle_t cycle_interval; > > > + u64

Re: [PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread Daniel Walker
On Tue, 2007-03-20 at 10:58 -0700, john stultz wrote: > > /* timekeeping specific data, ignore */ > > - cycle_t cycle_last, cycle_interval; > > - u64 xtime_nsec, xtime_interval; > > + cycle_t cycle_interval; > > + u64 xtime_interval; > > + /* > > +* Second part is written at

Re: [PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread john stultz
On Tue, 2007-03-20 at 11:09 +0100, Eric Dumazet wrote: > struct clocksource is a critical data structure. > > Most of its fields are read only, some of them are heavily modified at each > timer interrupt. > > It makes sense to separate those fields and make sure they all share one > cache

[PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread Eric Dumazet
struct clocksource is a critical data structure. Most of its fields are read only, some of them are heavily modified at each timer interrupt. It makes sense to separate those fields and make sure they all share one cache line, or at least the minimum for machines with small cache lines.

[PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread Eric Dumazet
struct clocksource is a critical data structure. Most of its fields are read only, some of them are heavily modified at each timer interrupt. It makes sense to separate those fields and make sure they all share one cache line, or at least the minimum for machines with small cache lines.

Re: [PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread john stultz
On Tue, 2007-03-20 at 11:09 +0100, Eric Dumazet wrote: struct clocksource is a critical data structure. Most of its fields are read only, some of them are heavily modified at each timer interrupt. It makes sense to separate those fields and make sure they all share one cache line, or at

Re: [PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread Daniel Walker
On Tue, 2007-03-20 at 10:58 -0700, john stultz wrote: /* timekeeping specific data, ignore */ - cycle_t cycle_last, cycle_interval; - u64 xtime_nsec, xtime_interval; + cycle_t cycle_interval; + u64 xtime_interval; + /* +* Second part is written at each timer

Re: [PATCH] time : SMP friendly alignment of struct clocksource

2007-03-20 Thread john stultz
On Tue, 2007-03-20 at 11:04 -0700, Daniel Walker wrote: On Tue, 2007-03-20 at 10:58 -0700, john stultz wrote: /* timekeeping specific data, ignore */ - cycle_t cycle_last, cycle_interval; - u64 xtime_nsec, xtime_interval; + cycle_t cycle_interval; + u64 xtime_interval; +