On Fri, 2014-10-03 at 06:54 -0500, Christoph Lameter wrote: > On Fri, 3 Oct 2014, Thomas Gleixner wrote: > > > > Is this the way its intended or should the counters be expanded to 64 bit? > > > > There is no reason why we cannot or should not expand them. > > Ok here is a patch to do just that: > > > Subject: Increase irq counters to 64 bit > > > Irq counters can overflow easily if they are just 32 bit. > > For example the timer interrupt occurs 1000 times per second, so > it is predictable that the timer interrupt will overflow in > > > 2^ 32 / 1000 [interrupts per second] / 86400 [seconds in a day] > > which results in 46 days.
dc -e "1 k 2 32 ^ 1000 / 86400 / p" 49.7 (That was the number I remembered from stories about a ancient Windows lockup.) > Other irq counters for devices may wrap even faster for example > those for high speed networking devices. > > This patch is needed to avoid the counter overflow by increasing > the counters to 64 bit. > > Signed-off-by: Christoph Lameter <c...@linux.com> Paul Bolle -- 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/
