168  * sugov_iowait_reset() - Reset the IO boost status of a CPU.
169  * @sg_cpu: the sugov data for the CPU to boost
171  * @set_iowait_boost: true if an IO boost has been requested
173  * The IO wait boost of a task is disabled after a tick since the last update
174  * of a CPU. If a new IO wait boost is requested after more then a tick, then
175  * we enable the boost starting from IOWAIT_BOOST_MIN, which improves energy
183 	/* Reset boost only if a tick has elapsed since last request */  in sugov_iowait_reset()
194  * sugov_iowait_boost() - Updates the IO boost status of a CPU.
195  * @sg_cpu: the sugov data for the CPU to boost
204  * To keep doubling, an IO boost has to be requested at least once per tick,
212 	/* Reset boost if the CPU appears to have been idle enough */  in sugov_iowait_boost()
217 	/* Boost only tasks waking up after IO */  in sugov_iowait_boost()
221 	/* Ensure boost doubles only one time at each request */  in sugov_iowait_boost()
226 	/* Double the boost at each request */  in sugov_iowait_boost()
233 	/* First wakeup after IO: start with minimum boost */  in sugov_iowait_boost()
238  * sugov_iowait_apply() - Apply the IO boost to a CPU.
239  * @sg_cpu: the sugov data for the cpu to boost
244  * The IO boost value is increased each time a task wakes up from IO, in
249  * its IO boost utilization reset.
251  * This mechanism is designed to boost high frequently IO waiting tasks, while
256 	unsigned long boost;  in sugov_iowait_apply()  local
258 	/* No boost currently required */  in sugov_iowait_apply()
262 	/* Reset boost if the CPU appears to have been idle enough */  in sugov_iowait_apply()
268 		 * No boost pending; reduce the boost value.  in sugov_iowait_apply()
283 	boost = (sg_cpu->iowait_boost * sg_cpu->max) >> SCHED_CAPACITY_SHIFT;  in sugov_iowait_apply()
284 	boost = uclamp_rq_util_with(cpu_rq(sg_cpu->cpu), boost, NULL);  in sugov_iowait_apply()
285 	if (sg_cpu->util < boost)  in sugov_iowait_apply()
286 		sg_cpu->util = boost;  in sugov_iowait_apply()