Re: [PATCH 3/5] lockstat: core infrastructure

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, 2007-05-29 at 14:52 +0200, Peter Zijlstra wrote:
> +       now = sched_clock();
> +       waittime = now - hlock->waittime_stamp;
> + 

It looks like your using sched_clock() through out .. It's a little
troubling considering the constraints on the function .. Most
architecture implement a jiffies sched_clock() w/ 1 millisecond or worse
resolution.. I'd imagine a millisecond hold time is pretty rare, even a
millisecond wait time might be fairly rare too ..  There's also no
guarantee that sched_clock timestamps off two different cpu's can be
compared (or at least that's my understanding) ..

Daniel

-
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/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux