Messages in this thread | | | Date | Mon, 7 Jul 2014 14:44:09 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH] sched: fix possible divide by zero in avg_atom calculation |
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On Sat, Jun 14, 2014 at 03:00:09PM +0200, Mateusz Guzik wrote: > proc_sched_show_task does: > if (nr_switches) > do_div(avg_atom, nr_switches); > > nr_switches is unsigned long and do_div truncates it to 32 bits, which > means it can test non-zero on e.g. x86-64 and be truncated to zero for > division. > > Fix the problem by using div64_ul instead. > > As a side effect calculations of avg_atom for big nr_switches are now correct. > > Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Thanks. [unhandled content-type:application/pgp-signature] | |