I was wondering if anyone could shed some light on how the ARM system clock
is implemented in the CPU models. I am trying to do some performance
monitoring, and I noticed there is a PMU interface for v8, which is
awesome. However, when I try to use jiffies in Linux to measure time in the
kernel, it appears that the value is rarely updated. I suspect there is
some shortcut being taken (to increase simulation performance) that causes
jiffies to stay mostly static. I would like to avoid having to hook into
the simulator to read 'ticks' as an alternative, but if that is necessary,
any information on the "correct" way to do this would be appreciated.
FYI, I have tried both Simple Atomic and Detailed O3 ARM CPUs, using the
legacy 32-bit Linux ARM kernel (that's linked on the wiki).
gem5-users mailing list