The cached devfreq->cur may become stale when the hardware frequency is
changed externally (e.g. by another core or governor). This causes
driver_target to incorrectly skip frequency transitions when the target
matches the cached value but differs from the actual hardware frequency.
Use driver->get_frequency() to read the real hardware frequency for the
unchanged check, and sync devfreq->cur on match to keep the cache correct.
Signed-off-by: guanyi3 <guanyi3@xiaomi.com>
When devfreq_gov_ondemand_stop() is called from idle task context,
work_cancel() is used instead of work_cancel_sync(), which does not
wait for the currently running worker to complete. If
devfreq_gov_ondemand_exit() then frees governor_data, the worker
may still be accessing it, causing a use-after-free crash.
Fix this by:
- Nullifying dev->governor_data under dev->lock in exit before freeing.
- Moving the governor_data read inside dev->lock in the worker and
adding a NULL check to bail out early if data has been freed.
Signed-off-by: guanyi3 <guanyi3@xiaomi.com>
Add devfreq ondemand governor that scales device frequency based on CPU load. When CPU load exceeds the configured threshold, frequency is set to maximum; otherwise it is scaled proportionally.
Signed-off-by: guanyi3 <guanyi3@xiaomi.com>