linux-uconsole/kernel
Joonwoo Park ae0177aba1 sched: WALT: account cumulative window demand
Energy cost estimation has been a long lasting challenge for WALT
because WALT guides CPU frequency based on the CPU utilization of
previous window.  Consequently it's not possible to know newly
waking-up task's energy cost until WALT's end of the current window.

The WALT already tracks 'Previous Runnable Sum' (prev_runnable_sum)
and 'Cumulative Runnable Average' (cr_avg).  They are designed for
CPU frequency guidance and task placement but unfortunately both
are not suitable for the energy cost estimation.

It's because using prev_runnable_sum for energy cost calculation would
make us to account CPU and task's energy solely based on activity in the
previous window so for example, any task didn't have an activity in the
previous window will be accounted as a 'zero energy cost' task.
Energy estimation with cr_avg is what energy_diff() relies on at present.
However cr_avg can only represent instantaneous picture of energy cost
thus for example, if a CPU was fully occupied for an entire WALT window
and became idle just before window boundary, and if there is a wake-up,
energy_diff() accounts that CPU is a 'zero energy cost' CPU.

As a result, introduce a new accounting unit 'Cumulative Window Demand'.
The cumulative window demand tracks all the tasks' demands have seen in
current window which is neither instantaneous nor actual execution time.
Because task demand represents estimated scaled execution time when the
task runs a full window, accumulation of all the demands represents
predicted CPU load at the end of window.

Thus we can estimate CPU's frequency at the end of current WALT window
with the cumulative window demand.

The use of prev_runnable_sum for the CPU frequency guidance and cr_avg
for the task placement have not changed and these are going to be used
for both purpose while this patch aims to add an additional statistics.

Change-Id: I9908c77ead9973a26dea2b36c001c2baf944d4f5
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
2017-11-20 21:15:59 +05:30
..
bpf Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-11-20 20:53:19 +05:30
configs kconfig: tinyconfig: provide whole choice blocks to avoid warnings 2016-09-24 10:07:42 +02:00
debug UPSTREAM: module: use a structure to encapsulate layout. 2017-08-11 19:31:04 +05:30
events Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-11-20 20:53:19 +05:30
gcov Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-09-03 12:01:45 +08:00
irq genirq: Release resources in __setup_irq() error path 2017-06-26 07:13:10 +02:00
livepatch livepatch: x86: fix relocation computation with kASLR 2015-11-11 17:36:04 +01:00
locking Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-11-20 20:53:19 +05:30
power Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-10-13 23:14:45 +08:00
printk UPSTREAM: printk: when dumping regs, show the stack, not thread_info 2017-08-11 19:31:04 +05:30
rcu Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-11-20 20:53:19 +05:30
sched sched: WALT: account cumulative window demand 2017-11-20 21:15:59 +05:30
time Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-10-09 14:32:35 +08:00
trace FROMLIST: tracing: Add support for preempt and irq enable/disable events 2017-10-15 23:53:55 +05:30
.gitignore certs: add .gitignore to stop git nagging about x509_certificate_list 2015-10-21 15:18:35 +01:00
acct.c
async.c
audit.c BACKPORT: audit: consistently record PIDs with task_tgid_nr() 2016-10-12 17:34:22 +05:30
audit.h audit: audit_tree_match can be boolean 2015-11-04 08:23:51 -05:00
audit_fsnotify.c audit: clean simple fsnotify implementation 2015-08-06 16:14:53 -04:00
audit_tree.c audit: audit_tree_match can be boolean 2015-11-04 08:23:51 -05:00
audit_watch.c audit: Fix use after free in audit_remove_watch_rule() 2017-08-24 17:02:35 -07:00
auditfilter.c audit: fix comment block whitespace 2015-11-04 08:23:51 -05:00
auditsc.c BACKPORT: audit: consistently record PIDs with task_tgid_nr() 2016-10-12 17:34:22 +05:30
backtracetest.c
bounds.c
capability.c exec: Ensure mm->user_ns contains the execed files 2017-01-06 11:16:14 +01:00
cgroup.c Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-04-23 12:02:14 +08:00
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
compat.c
configs.c
context_tracking.c context_tracking: avoid irq_save/irq_restore on guest entry and exit 2015-11-10 12:06:23 +01:00
cpu.c Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-01-13 12:01:52 +08:00
cpu_pm.c kernel/cpu_pm: fix cpu_cluster_pm_exit comment 2015-09-03 02:42:20 +02:00
cpuset.c Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-10-13 23:14:45 +08:00
crash_dump.c
cred.c cred: Reject inodes with invalid ids in set_create_file_as() 2016-09-15 08:27:49 +02:00
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 kernel/extable.c: mark core_kernel_text notrace 2017-07-21 07:44:56 +02:00
fork.c BACKPORT: partial: mm, oom_reaper: do not mmput synchronously from the oom reaper context 2017-10-15 23:21:09 +05:30
freezer.c
futex.c Merge tag 'v4.4.56' into linux-linaro-lsk-v4.4 2017-03-23 12:00:54 +08:00
futex_compat.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
groups.c
hung_task.c
irq_work.c treewide: Remove old email address 2015-11-23 09:44:58 +01:00
jump_label.c jump_labels: API for flushing deferred jump label updates 2017-01-19 20:17:19 +01:00
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.c s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres() 2017-10-25 11:26:32 +08:00
kexec_core.c s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres() 2017-10-25 11:26:32 +08:00
kexec_file.c kexec: introduce a protection mechanism for the crashkernel reserved memory 2017-10-25 11:23:52 +08:00
kexec_internal.h kexec: split kexec_file syscall code to kexec_file.c 2015-09-10 13:29:01 -07:00
kmod.c kmod: don't run async usermode helper as a child of kworker thread 2015-10-23 17:55:10 +09:00
kprobes.c tracing/kprobes: Enforce kprobes teardown after testing 2017-05-25 14:30:17 +02:00
ksysfs.c kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
kthread.c UPSTREAM: kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function 2017-08-11 19:31:04 +05:30
latencytop.c
Makefile sys_membarrier(): system-wide memory barrier (generic, x86) 2015-09-11 15:21:34 -07:00
membarrier.c Fix: Disable sys_membarrier when nohz_full is enabled 2017-03-12 06:37:26 +01:00
memremap.c mm: fix devm_memremap_pages crash, use mem_hotplug_{begin, done} 2017-01-19 20:17:18 +01:00
module-internal.h
module.c UPSTREAM: modules: fix longstanding /proc/kallsyms vs module insertion race. 2017-08-11 19:31:04 +05:30
module_signing.c KEYS: Merge the type-specific data with the payload data 2015-10-21 15:18:36 +01:00
notifier.c Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 08:40:25 -07:00
nsproxy.c
padata.c padata: free correct variable 2017-05-20 14:27:02 +02:00
panic.c kernel/panic.c: add missing \n 2017-07-05 14:37:19 +02:00
params.c Nothing exciting, minor tweaks and cleanups. 2015-11-09 15:53:39 -08:00
pid.c pids: make task_tgid_nr_ns() safe 2017-08-24 17:02:36 -07:00
pid_namespace.c pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes 2017-05-25 14:30:11 +02:00
profile.c mm: rename alloc_pages_exact_node() to __alloc_pages_node() 2015-09-08 15:35:28 -07:00
ptrace.c ptrace: Properly initialize ptracer_cred on fork 2017-06-14 13:16:20 +02:00
range.c
reboot.c kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
relay.c kernel/relay.c: use kvfree() in relay_free_page_array() 2015-06-30 19:44:59 -07:00
resource.c /proc/iomem: only expose physical resource addresses to privileged users 2017-08-06 19:19:42 -07:00
seccomp.c seccomp: fix the usage of get/put_seccomp_filter() in seccomp_get_filter() 2017-10-05 09:41:46 +02:00
signal.c signal: protect SIGNAL_UNKILLABLE from unintentional clearing. 2017-08-11 09:08:59 -07:00
smp.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
smpboot.c stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark() 2015-10-20 10:23:55 +02:00
smpboot.h
softirq.c
stacktrace.c
stop_machine.c kernel: remove stop_machine() Kconfig dependency 2015-12-12 10:15:34 -08:00
sys.c BACKPORT: timer: convert timer_slack_ns from unsigned long to u64 2016-07-11 12:43:04 +05:30
sys_ni.c mm: mlock: add new mlock system call 2015-11-05 19:34:48 -08:00
sysctl.c Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-10-09 14:32:35 +08:00
sysctl_binary.c fs/coredump: prevent fsuid=0 dumps into user-controlled directories 2016-04-12 09:08:58 -07:00
task_work.c task_work: remove fifo ordering guarantee 2015-09-05 13:46:58 -07:00
taskstats.c
test_kprobes.c
torture.c torture: Consolidate cond_resched_rcu_qs() into stutter_wait() 2015-10-06 11:25:01 -07:00
tracepoint.c tracepoint: Give priority to probes of tracepoints 2015-10-25 21:33:54 -04:00
tsacct.c
uid16.c
up.c
user-return-notifier.c
user.c
user_namespace.c capabilities: ambient capabilities 2015-09-04 16:54:41 -07:00
utsname.c
utsname_sysctl.c
watchdog.c Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2017-01-09 12:01:35 +08:00
workqueue.c workqueue: replace pool->manager_arb mutex with a flag 2017-11-02 09:40:48 +01:00
workqueue_internal.h workqueue: Fix NULL pointer dereference 2017-11-15 17:13:11 +01:00