Qemu just can't handle 1000 Hz ticks. On our CI machines, CONFIG_HZ
on the host (which is the limit of timing precision for things like
idle wakeups and signal delivery, both of which qemu seems to use for
timing) is 250. When the mismatch gets this large, we start seeing
artifacts like interrupts being delivered "in the past" (i.e. code
sees a z_clock_elapsed() value of "2" ticks before getting a
z_clock_announce() call for "1").
As it happens, this test doesn't actually require timing with that
precision, it just wants "lots of context switching" to exercise the
threadsafety of the mem_pool APIs. So decrease the tick rate to the
100Hz default, but put a loop counter in the worker threads to force
them to do 10x more work, keeping the number of preemptions constant.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
c4e2f1b217