On 29/05/18 12:56, Geert Uytterhoeven wrote:

Hi Sudeep,

On Tue, May 29, 2018 at 1:14 PM, Sudeep Holla [off-list ref] wrote:

quoted

On 29/05/18 11:48, Geert Uytterhoeven wrote:

quoted

On Thu, May 17, 2018 at 7:05 PM, Catalin Marinas
[off-list ref] wrote:

quoted

On Fri, May 11, 2018 at 06:57:55PM -0500, Jeremy Linton wrote:

quoted

Jeremy Linton (12):
  drivers: base: cacheinfo: move cache_setup_of_node()
  drivers: base: cacheinfo: setup DT cache properties early
  cacheinfo: rename of_node to fw_token
  arm64/acpi: Create arch specific cpu to acpi id helper
  ACPI/PPTT: Add Processor Properties Topology Table parsing
  ACPI: Enable PPTT support on ARM64
  drivers: base cacheinfo: Add support for ACPI based firmware tables
  arm64: Add support for ACPI based firmware tables
  arm64: topology: rename cluster_id
  arm64: topology: enable ACPI/PPTT based CPU topology
  ACPI: Add PPTT to injectable table list
  arm64: topology: divorce MC scheduling domain from core_siblings

Queued for 4.18 (without Sudeep's latest property_read_u64 cacheinfo
patch - http://lkml.kernel.org/r/20180517154701.GA20281 at e107155-lin; I
can add it separately).

This is now commit 37c3ec2d810f87ea ("arm64: topology: divorce MC
scheduling domain from core_siblings") in arm64/for-next/core, causing
system suspend on big.LITTLE systems to hang after shutting down the first
CPU:

    $ echo mem > /sys/power/state
    PM: suspend entry (deep)
    PM: Syncing filesystems ... done.
    Freezing user space processes ... (elapsed 0.001 seconds) done.
    OOM killer disabled.
    Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
    Disabling non-boot CPUs ...
    CPU1: shutdown
    psci: CPU1 killed.

Is it OK to assume the suspend failed just after shutting down one CPU
or it's failing during resume ? It depends on whether you had console
disabled or not.

I have no-console-suspend enabled.
It's failing during suspend, the next lines should be:

    CPU2: shutdown
    psci: CPU2 killed.
    ...

OK, I was hoping to be something during resume as this patch has nothing
executed during suspend. Do you see any change in topology before and
after this patch applied. I am interested in the output of:

$ grep "" /sys/devices/system/cpu/cpu*/topology/*

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For me, it fails on the following big.LITTLE systems:

    R-Car H3 ES2.0 (4xCA57 + 4xCA53)
    R-Car M3-W (2xCA57 + 4xCA53)

Interesting, is it PSCI based system suspend ?

Yes it is.

Suspend-to-idle, which doesn't offline CPUs, still works.

From DT, I guess this platform doesn't have any idle states.

Does this use genpd power domains ? I see power-domains in the DT, so
asking to get more info. Do you have any out of tree patches especially
if they are depending on some topology cpumasks ?

quoted

quoted

System supend still works fine on systems with big cores only:

    R-Car H3 ES1.0 (4xCA57 (4xCA53 disabled in firmware))
    R-Car M3-N (2xCA57)

Reverting this commit fixes the issue for me.

I can't find anything that relates to system suspend in these patches
unless they are messing with something during CPU hot plug-in back
during resume.

It's only the last patch that introduces the breakage.

As specified in the commit log, it won't change any behavior for DT
systems if it's non-NUMA or single node system. So I am still wondering
what could trigger this regression.

-- 
Regards,
Sudeep