On Fri, Feb 22, 2013 at 06:21:31AM -0800, Eric Dumazet wrote: > On Fri, 2013-02-22 at 15:09 +0100, Peter Zijlstra wrote: > > On Fri, 2013-02-22 at 13:50 +0100, Frederic Weisbecker wrote: > > > > Argh!! at what cost? 64bit atomics are like expensive. Wouldn't > > > adding > > > > a seqlock be saner? > > > > > > Not sure. This requires a spinlock in the write side which is called > > > from > > > fast path like the timer interrupt. > > > > A single spinlock is _way_ cheaper than a ton of cmpxchg8b()s to update > > a few variables. > > We also have include/linux/u64_stats_sync.h since 2.6.36
Interesting, we should probably use that instead. -- 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/
