def _from_target(
cls,
target: Target,
*,
res_dir: ArtifactPath = None,
collector=None,
) -> 'UtilTrackingBase':
plat_info = target.plat_info
rtapp_profile = cls.get_rtapp_profile(plat_info)
# After a bit of experimenting, it turns out that on some platforms
# misprediction of the idle time (which leads to a shallow idle state,
# a wakeup and another idle nap) can mess up the duty cycle of the
# rt-app task we're running. In our case, a 50% duty cycle, 16ms period
# task would always be active for 8ms, but it would sometimes sleep for
# only 5 or 6 ms.
# This is fine to do this here, as we only care about the proper
# behaviour of the signal on running/not-running tasks.
with target.disable_idle_states():
with target.cpufreq.use_governor('performance'):
cls.run_rtapp(target,
res_dir,
rtapp_profile,
collector=collector)
return cls(res_dir, plat_info)
def _from_target(cls,
target: Target,
*,
res_dir: ArtifactPath = None,
collector=None) -> 'EASBehaviour':
"""
:meta public:
Factory method to create a bundle using a live target
This will execute the rt-app workload described in
:meth:`lisa.tests.base.RTATestBundle.get_rtapp_profile`
"""
plat_info = target.plat_info
rtapp_profile = cls.get_rtapp_profile(plat_info)
# EAS doesn't make a lot of sense without schedutil,
# so make sure this is what's being used
with target.disable_idle_states():
with target.cpufreq.use_governor("schedutil"):
cls.run_rtapp(target,
res_dir,
rtapp_profile,
collector=collector)
return cls(res_dir, plat_info)
def _from_target(cls, target: Target, *, res_dir: ArtifactPath = None, ftrace_coll: FtraceCollector = None, cpu=None, nr_steps=1) -> 'LargeStepUp':
plat_info = target.plat_info
# Use a big CPU by default to allow maximum range of utilization
cpu = cpu if cpu is not None else plat_info["capacity-classes"][-1][0]
rtapp_profile = cls.get_rtapp_profile(plat_info, cpu=cpu, nr_steps=nr_steps)
# Ensure accurate duty cycle and idle state misprediction on some
# boards. This helps having predictable execution.
with target.disable_idle_states():
with target.cpufreq.use_governor("schedutil"):
cls.run_rtapp(target, res_dir, rtapp_profile, ftrace_coll=ftrace_coll)
return cls(res_dir, plat_info, cpu, nr_steps)