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3a7e623182
The current definition of the Performance Boost (PB) and Performance Constraint (PC) regions is has two main issues: 1) in the computation of the boost index we overflow the thresholds_gains table for boost=100 2) the two cuts had _NOT_ the same ratio The last point means that when boost=0 we do _not_ have a "standard" EAS behaviour, i.e. accepting all candidate which decrease energy regardless of their impact on performances. Instead, we accept only schedule candidate which are in the Optimal region, i.e. decrease energy while increasing performances. This behaviour can have a negative impact also on CPU selection policies which tries to spread tasks to reduce latencies. Indeed, for example we could end up rejecting a schedule candidate which want to move a task from a congested CPU to an idle one while, specifically in the case where the target CPU will be running on a lower OPP. This patch fixes these two issues by properly clamping the boost value in the appropriate range to compute the threshold indexes as well as by using the same threshold index for both cuts. Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com> Signed-off-by: Srinath Sridharan <srinathsr@google.com> sched/tune: fix update of threshold index for boost groups When SchedTune is configured to work with CGroup mode, each time we update the boost value of a group we do not update the threshed indexes for the definition of the Performance Boost (PC) and Performance Constraint (PC) region. This means that while the OPP boosting and CPU biasing selection is working as expected, the __schedtune_accept_deltas function is always using the initial values for these cuts. This patch ensure that each time a new boost value is configured for a boost group, the cuts for the PB and PC region are properly updated too. Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com> Signed-off-by: Srinath Sridharan <srinathsr@google.com> sched/tune: update PC and PB cuts definition The current definition of Performance Boost (PB) and Performance Constraint (PC) cuts defines two "dead regions": - up to 20% boost: we are in energy-reduction only mode, i.e. accept all candidate which reduce energy - over 70% boost: we are in performance-increase only mode, i.e. accept only sched candidate which do not reduce performances This patch uses a more fine grained configuration where these two "dead regions" are reduced to: up to 10% and over 90%. This should allow to have some boosting benefits starting from 10% boost values as well as not being to much permissive starting from boost values of 80%. Suggested-by: Leo Yan <leo.yan@linaro.org> Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com> Signed-off-by: Srinath Sridharan <srinathsr@google.com> bug: 28312446 Change-Id: Ia326c66521e38c98e7a7eddbbb7c437875efa1ba Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com> |
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| .. | ||
| auto_group.c | ||
| auto_group.h | ||
| clock.c | ||
| completion.c | ||
| core.c | ||
| cpuacct.c | ||
| cpuacct.h | ||
| cpudeadline.c | ||
| cpudeadline.h | ||
| cpufreq_sched.c | ||
| cpupri.c | ||
| cpupri.h | ||
| cputime.c | ||
| deadline.c | ||
| debug.c | ||
| energy.c | ||
| fair.c | ||
| features.h | ||
| idle_task.c | ||
| idle.c | ||
| loadavg.c | ||
| Makefile | ||
| rt.c | ||
| sched.h | ||
| stats.c | ||
| stats.h | ||
| stop_task.c | ||
| tune.c | ||
| tune.h | ||
| wait.c | ||