linux/kernel
Patrick Bellasi 3a7e623182 sched/tune: fix PB and PC cuts indexes definition
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>
2016-09-14 14:59:32 +05:30
..
bpf bpf, inode: disallow userns mounts 2016-06-24 10:18:17 -07:00
configs
debug Merge remote-tracking branch 'lsk/linux-linaro-lsk-v4.4-android' into linux-linaro-lsk-v4.4-android 2016-03-18 09:50:49 +00:00
events Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-08-30 10:27:13 +08:00
gcov
irq genirq: Validate action before dereferencing it in handle_irq_event_percpu() 2016-03-03 15:07:11 -08:00
livepatch
locking RFC: FROMLIST: locking/percpu-rwsem: Optimize readers and reduce global impact 2016-09-14 14:26:20 +05:30
power Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-04-13 12:02:21 +08:00
printk Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-02-29 10:18:54 +08:00
rcu ANDROID: rcu_sync: Export rcu_sync_lockdep_assert 2016-09-14 14:26:20 +05:30
sched sched/tune: fix PB and PC cuts indexes definition 2016-09-14 14:59:32 +05:30
time Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-08-11 12:15:55 +08:00
trace Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-07-29 21:38:37 +01:00
.gitignore
acct.c
async.c
audit_fsnotify.c
audit_tree.c
audit_watch.c
audit.c
audit.h
auditfilter.c
auditsc.c
backtracetest.c
bounds.c
capability.c
cgroup_freezer.c cgroup: fix handling of multi-destination migration from subtree_control enabling 2015-12-03 10:18:21 -05:00
cgroup_pids.c cgroup_pids: don't account for the root cgroup 2015-12-03 10:18:21 -05:00
cgroup.c RFC: FROMLIST: cgroup: avoid synchronize_sched() in __cgroup_procs_write() 2016-09-14 14:26:20 +05:30
compat.c
configs.c
context_tracking.c
cpu_pm.c
cpu.c ANDROID: cpu: send KOBJ_ONLINE event when enabling cpus 2016-07-11 12:42:46 +05:30
cpuset.c cpuset: Make cpusets restore on hotplug 2016-09-14 14:44:29 +05:30
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c FIXUP: sched/tune: fix accounting for runnable tasks 2016-09-14 14:59:32 +05:30
extable.c
fork.c RFC: FROMLIST: cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork 2016-09-14 14:26:20 +05:30
freezer.c
futex_compat.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
futex.c x86: remove more uaccess_32.h complexity 2016-08-27 11:23:38 +08:00
groups.c
hung_task.c
irq_work.c
jump_label.c locking/static_key: Fix concurrent static_key_slow_inc() 2016-07-27 09:47:29 -07:00
kallsyms.c
kcmp.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec_core.c
kexec_file.c
kexec_internal.h
kexec.c
kmod.c
kprobes.c
ksysfs.c
kthread.c
latencytop.c
Makefile
membarrier.c
memremap.c devm_memremap: Fix error value when memremap failed 2016-03-03 15:07:08 -08:00
module_signing.c
module-internal.h
module.c modules: fix longstanding /proc/kallsyms vs module insertion race. 2016-03-09 15:34:56 -08:00
notifier.c
nsproxy.c
padata.c
panic.c Revert "panic: Add board ID to panic output" 2016-08-18 18:56:03 +05:30
params.c
pid_namespace.c
pid.c pidns: fix NULL dereference in __task_pid_nr_ns() 2015-11-24 12:03:55 -08:00
profile.c
ptrace.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
range.c
reboot.c
relay.c
resource.c kernel/resource.c: fix muxed resource handling in __request_region() 2016-03-03 15:07:29 -08:00
seccomp.c seccomp: always propagate NO_NEW_PRIVS on tsync 2016-03-03 15:07:25 -08:00
signal.c
smp.c
smpboot.c
smpboot.h
softirq.c
stacktrace.c
stop_machine.c kernel: remove stop_machine() Kconfig dependency 2015-12-12 10:15:34 -08:00
sys_ni.c
sys.c BACKPORT: timer: convert timer_slack_ns from unsigned long to u64 2016-07-11 12:43:04 +05:30
sysctl_binary.c fs/coredump: prevent fsuid=0 dumps into user-controlled directories 2016-04-12 09:08:58 -07:00
sysctl.c sched/fair: add tunable to set initial task load 2016-09-14 14:59:32 +05:30
task_work.c
taskstats.c
test_kprobes.c
torture.c
tracepoint.c
tsacct.c
uid16.c
up.c
user_namespace.c
user-return-notifier.c
user.c
utsname_sysctl.c
utsname.c
watchdog.c Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-04-13 12:02:21 +08:00
workqueue_internal.h
workqueue.c workqueue: fix rebind bound workers warning 2016-05-18 17:06:50 -07:00