On Thu, Sep 26, 2013 at 07:52:23AM -0400, Peter Hurley wrote: > On 09/25/2013 11:20 PM, Andi Kleen wrote: > >Lin Ming <min...@gmail.com> writes: > >> > >>Would you like below patch? > > > >The loop body keeps rather complex state. It could easily > >get confused by parallel RCU changes. > > > >So if the list changes in parallel you may suddenly > >report very bogus values, as the va_start - prev_end > >computation may be bogus. > > > >Perhaps it's ok (may report bogus gaps), but it seems a bit risky. > > I don't understand how the computed gap would be bogus; there > _was_ a list state in which that particular gap existed. The fact
It could change any time as you don't have an atomic view of vm_end / vm_start. It is valid to change the fields with the lock held. -Andi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
