cpuidle: Eliminate the CPUIDLE_DRIVER_STATE_START symbol
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 23 Aug 2017 21:19:57 +0000 (23:19 +0200)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 30 Aug 2017 01:05:29 +0000 (03:05 +0200)
commitdc2251bf98c66db3f4e055b751968f0871037ae4
treea18ffbaae6dc1e54069fd19ebcfc93b88d42a9fa
parent84dc4141f0353bada6af53d32730f3e47e579bc0
cpuidle: Eliminate the CPUIDLE_DRIVER_STATE_START symbol

On some architectures the first (index 0) idle state is a polling
one and it doesn't really save energy, so there is the
CPUIDLE_DRIVER_STATE_START symbol allowing some pieces of
cpuidle code to avoid using that state.

However, this makes the code rather hard to follow.  It is better
to explicitly avoid the polling state, so add a new cpuidle state
flag CPUIDLE_FLAG_POLLING to mark it and make the relevant code
check that flag for the first state instead of using the
CPUIDLE_DRIVER_STATE_START symbol.

In the ACPI processor driver that cannot always rely on the state
flags (like before the states table has been set up) define
a new internal symbol ACPI_IDLE_STATE_START equivalent to the
CPUIDLE_DRIVER_STATE_START one and drop the latter.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
drivers/acpi/processor_idle.c
drivers/cpuidle/driver.c
drivers/cpuidle/governors/ladder.c
drivers/cpuidle/governors/menu.c
include/linux/cpuidle.h