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4b20b07ce7
When bailing out early, teo will not query the sleep length anymore since commit 6da8f9ba5a87 ("cpuidle: teo: Skip tick_nohz_get_sleep_length() call in some cases") with an expected sleep_length_ns value of KTIME_MAX. This lead to state0 accumulating lots of 'intercepts' because the actually measured sleep length was < KTIME_MAX, so query the sleep length instead for teo to recognize if it still is in an intercept-likely scenario without alternating between the two modes. Fundamentally we can only do one of the two: 1. Skip sleep_length_ns query when we think intercept is likely. 2. Have accurate data if sleep_length_ns is actually intercepted when we believe it is currently intercepted. Previously teo did the former while this patch chooses the latter as the additional time it takes to query the sleep length was found to be negligible and the variants of option 1 (count all unknowns as misses or count all unknown as hits) had significant regressions (as misses had lots of too shallow idle state selections and as hits had terrible performance in intercept-heavy workloads). Fixes: 6da8f9ba5a87 ("cpuidle: teo: Skip tick_nohz_get_sleep_length() call in some cases") Link: https://patch.msgid.link/c40acf72-010f-4a8b-80e4-33f133ba266b@arm.com Signed-off-by: Christian Loehle <christian.loehle@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>