* Andrew Morton [off-list ref] [180112 00:45]:

On Thu, 11 Jan 2018 16:23:22 -0800 Tony Lindgren [off-list ref] wrote:

quoted

* Andrew Morton [off-list ref] [180112 00:18]:

quoted

On Thu, 11 Jan 2018 16:01:13 -0800 Tony Lindgren [off-list ref] wrote:

quoted

Hi all,

I'm seeing a considerable idle power consumption regression in
Linux next, with power consumption for my idle test system going
to 17.5mW compared to the usual 8mW on my test device.

Git bisect points to merge commit e130bc1d00a4 ("Merge branch
'akpm-current/current'") being the first bad commit.

I have also verified that commit 70286688e5ad ("ipc/mqueue.c:
have RT tasks queue in by priority in wq_add()") is good, and
commit e2d7fe89e8ae ("Merge remote-tracking branch
'init_task/init_task'") is good.

Do you mean that everything up to and including 70286688e5ad
("ipc/mqueue.c: have RT tasks queue in by priority in wq_add()") is
good?

Yes I'm not seeing the regression in your branch at commit
70286688e5ad. I'm seeing it only with the merge commit
e130bc1d00a4.

That's weird.  All I'm seeing between 70286688e5ad and end-of-mm is:

tools-objtool-makefile-dont-assume-sync-checksh-is-executable.patch
ipc-mqueue-add-missing-error-code-in-init_mqueue_fs.patch

vfs-remove-might_sleep-from-clear_inode.patch

mm-remove-duplicate-includes.patch

mm-remove-unneeded-kallsyms-include.patch
hrtimer-remove-unneeded-kallsyms-include.patch
genirq-remove-unneeded-kallsyms-include.patch

mm-memblock-memblock_is_map-region_memory-can-be-boolean.patch
lib-lockref-__lockref_is_dead-can-be-boolean.patch
kernel-cpuset-current_cpuset_is_being_rebound-can-be-boolean.patch
kernel-resource-iomem_is_exclusive-can-be-boolean.patch
kernel-module-module_is_live-can-be-boolean.patch
kernel-mutex-mutex_is_locked-can-be-boolean.patch
crash_dump-is_kdump_kernel-can-be-boolean.patch

fix-const-confusion-in-certs-blacklist.patch
fix-read-buffer-overflow-in-delta-ipc.patch

kasan-rework-kconfig-settings.patch

sparc64-ng4-memset-32-bits-overflow.patch

lib-crc-ccitt-add-ccitt-false-crc16-variant.patch

Well there are some changes in merge commit e130bc1d00a4..

And I don't see how any of those can cause this.  Did anything else
change, like context switch rates, interrupt rates, etc?

Well I tried to measure suspend power consumption and noticed
that system suspend fails too hand hangs the network device:

# echo mem > /sys/power/state
[   32.577850] PM: suspend entry (deep)
[   32.582031] PM: Syncing filesystems ... done.
[   32.598083] Freezing user space processes ... (elapsed 0.002 seconds) done.
[   32.608398] OOM killer disabled.
[   32.611846] Freezing remaining freezable tasks ... (elapsed 0.002 seconds) done.
[   32.622192] Suspending console(s) (use no_console_suspend to debug)
[   32.651123] dpm_run_callback(): mdio_bus_suspend+0x0/0x24 returns 4352
[   32.651428] PM: Device 2c000000.ethernet-ffffffff:01 failed to suspend: error 4352
[   32.653289] PM: Some devices failed to suspend, or early wake event detected
[   32.685455] OOM killer enabled.
[   32.688629] Restarting tasks ... done.
[   32.695983] PM: suspend exit
ash: write error: Bad address

That too works just fine at commit 70286688e5ad.

Regards,

Tony