Morten Rasmussen 0c1dc6b27d sched: Make sched entity usage tracking scale-invariant ...

Apply frequency scale-invariance correction factor to usage tracking.

Each segment of the running_avg_sum geometric series is now scaled by the
current frequency so the utilization_avg_contrib of each entity will be
invariant with frequency scaling.

As a result, utilization_load_avg which is the sum of utilization_avg_contrib,
becomes invariant too. So the usage level that is returned by get_cpu_usage(),
stays relative to the max frequency as the cpu_capacity which is is compared against.

Then, we want the keep the load tracking values in a 32-bit type, which implies
that the max value of {runnable|running}_avg_sum must be lower than
2^32/88761=48388 (88761 is the max weigth of a task). As LOAD_AVG_MAX = 47742,
arch_scale_freq_capacity() must return a value less than
(48388/47742) << SCHED_CAPACITY_SHIFT = 1037 (SCHED_SCALE_CAPACITY = 1024).
So we define the range to [0..SCHED_SCALE_CAPACITY] in order to avoid overflow.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Morten.Rasmussen@arm.com
Cc: Paul Turner <pjt@google.com>
Cc: dietmar.eggemann@arm.com
Cc: efault@gmx.de
Cc: kamalesh@linux.vnet.ibm.com
Cc: linaro-kernel@lists.linaro.org
Cc: nicolas.pitre@linaro.org
Cc: preeti@linux.vnet.ibm.com
Cc: riel@redhat.com
Link: http://lkml.kernel.org/r/1425455186-13451-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2015-03-27 09:36:00 +01:00

..

bpf

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-01-27 13:55:36 -08:00

configs

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debug

debug: prevent entering debug mode on panic/exception.

2015-02-19 12:39:03 -06:00

events

perf: Fix context leak in put_event()

2015-03-13 10:02:18 +01:00

gcov

kbuild,gcov: simplify kernel/gcov/Makefile more

2015-01-09 17:25:44 +01:00

irq

genirq / PM: Add flag for shared NO_SUSPEND interrupt lines

2015-03-04 21:42:19 +01:00

livepatch

livepatch: Fix subtle race with coming and going modules

2015-03-17 10:31:54 +01:00

locking

locking/rtmutex: Set state back to running on error

2015-03-01 09:45:06 +01:00

power

PM / sleep: Re-implement suspend-to-idle handling

2015-02-13 23:49:36 +01:00

printk

console: Fix console name size mismatch

2015-03-07 03:39:55 +01:00

rcu

Merge branches 'core-urgent-for-linus' and 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-02-21 10:36:06 -08:00

sched

sched: Make sched entity usage tracking scale-invariant

2015-03-27 09:36:00 +01:00

time

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-02-21 11:05:22 -08:00

trace

ftrace: Fix ftrace enable ordering of sysctl ftrace_enabled

2015-03-09 10:55:34 -04:00

.gitignore

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acct.c

new fs_pin killing logics

2015-01-25 23:17:28 -05:00

async.c

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audit_tree.c

fsnotify: unify inode and mount marks handling

2014-12-13 12:42:53 -08:00

audit_watch.c

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audit.c

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2014-12-30 10:45:47 -08:00

audit.h

audit: replace getname()/putname() hacks with reference counters

2015-01-23 00:23:58 -05:00

auditfilter.c

Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit

2015-02-11 20:07:47 -08:00

auditsc.c

Merge branch 'getname2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2015-02-17 15:27:47 -08:00

backtracetest.c

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bounds.c

…

capability.c

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cgroup_freezer.c

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cgroup.c

kernfs: remove KERNFS_STATIC_NAME

2015-02-13 21:21:36 -08:00

compat.c

all arches, signal: move restart_block to struct task_struct

2015-02-12 18:54:12 -08:00

configs.c

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context_tracking.c

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cpu_pm.c

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cpu.c

hotplugcpu: Avoid deadlocks by waking active_writer

2015-01-06 11:01:14 -08:00

cpuset.c

cpuset: Fix cpuset sched_relax_domain_level

2015-03-02 11:55:04 -05:00

crash_dump.c

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cred.c

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delayacct.c

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dma.c

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elfcore.c

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exec_domain.c

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exit.c

oom, PM: make OOM detection in the freezer path raceless

2015-02-11 17:06:03 -08:00

extable.c

ftrace/x86/extable: Add is_ftrace_trampoline() function

2014-11-19 15:25:26 -05:00

fork.c

mm: do not use mm->nr_pmds on !MMU configurations

2015-02-12 18:54:10 -08:00

freezer.c

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futex_compat.c

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futex.c

all arches, signal: move restart_block to struct task_struct

2015-02-12 18:54:12 -08:00

groups.c

userns: Don't allow setgroups until a gid mapping has been setablished

2014-12-09 16:58:40 -06:00

hung_task.c

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irq_work.c

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jump_label.c

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kallsyms.c

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kcmp.c

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Kconfig.freezer

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Kconfig.hz

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Kconfig.locks

locking/mcs: Better differentiate between MCS variants

2015-01-14 15:07:32 +01:00

Kconfig.preempt

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kexec.c

kexec: simplify conditional

2015-02-17 14:34:51 -08:00

kmod.c

usermodehelper: kill the kmod_thread_locker logic

2014-12-10 17:41:17 -08:00

kprobes.c

kprobes: makes kprobes/enabled works correctly for optimized kprobes.

2015-02-13 21:21:42 -08:00

ksysfs.c

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kthread.c

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latencytop.c

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Makefile

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2015-02-11 20:25:11 -08:00

module_signing.c

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module-internal.h

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module.c

kasan, module, vmalloc: rework shadow allocation for modules

2015-03-12 18:46:08 -07:00

notifier.c

rcu: Make SRCU optional by using CONFIG_SRCU

2015-01-06 11:04:29 -08:00

nsproxy.c

bury struct proc_ns in fs/proc

2014-12-04 14:34:54 -05:00

padata.c

padata: use %*pb[l] to print bitmaps including cpumasks and nodemasks

2015-02-13 21:21:38 -08:00

panic.c

livepatch: kernel: add TAINT_LIVEPATCH

2014-12-22 15:40:48 +01:00

params.c

param: fix uninitialized read with CONFIG_DEBUG_LOCK_ALLOC

2015-01-20 11:38:31 +10:30

pid_namespace.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2014-12-16 15:53:03 -08:00

pid.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2014-12-16 15:53:03 -08:00

profile.c

profile: use %*pb[l] to print bitmaps including cpumasks and nodemasks

2015-02-13 21:21:38 -08:00

ptrace.c

ptrace: remove linux/compat.h inclusion under CONFIG_COMPAT

2015-02-17 14:34:51 -08:00

range.c

kernel: avoid overflow in cmp_range

2015-01-17 10:02:23 +13:00

reboot.c

…

relay.c

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resource.c

resources: Move struct resource_list_entry from ACPI into resource core

2015-02-05 15:09:25 +01:00

seccomp.c

seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO

2015-02-17 14:34:55 -08:00

signal.c

signal: use current->state helpers

2015-02-17 14:34:51 -08:00

smp.c

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smpboot.c

smpboot: Add missing get_online_cpus() in smpboot_register_percpu_thread()

2015-01-23 11:33:51 +01:00

smpboot.h

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softirq.c

Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-02-09 15:24:03 -08:00

stacktrace.c

stacktrace: introduce snprint_stack_trace for buffer output

2014-12-13 12:42:48 -08:00

stop_machine.c

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sys_ni.c

syscalls: implement execveat() system call

2014-12-13 12:42:51 -08:00

sys.c

kernel/sys.c: fix UNAME26 for 4.0

2015-02-28 09:57:51 -08:00

sysctl_binary.c

kernel: add panic_on_warn

2014-12-10 17:41:10 -08:00

sysctl.c

mm, hugetlb: remove unnecessary lower bound on sysctl handlers"?

2015-02-10 14:30:34 -08:00

system_certificates.S

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system_keyring.c

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task_work.c

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taskstats.c

netlink: make nlmsg_end() and genlmsg_end() void

2015-01-18 01:03:45 -05:00

test_kprobes.c

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torture.c

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tracepoint.c

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tsacct.c

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uid16.c

groups: Consolidate the setgroups permission checks

2014-12-05 17:19:27 -06:00

up.c

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user_namespace.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2014-12-17 12:31:40 -08:00

user-return-notifier.c

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user.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2014-12-17 12:31:40 -08:00

utsname_sysctl.c

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utsname.c

copy address of proc_ns_ops into ns_common

2014-12-04 14:34:47 -05:00

watchdog.c

kernel/sched/clock.c: add another clock for use with the soft lockup watchdog

2015-02-12 18:54:13 -08:00

workqueue_internal.h

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workqueue.c

workqueue: fix hang involving racing cancel[_delayed]_work_sync()'s for PREEMPT_NONE

2015-03-05 08:04:13 -05:00