linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Kai-Heng Feng <kai.heng.feng@canonical.com>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Mario Limonciello <Mario.Limonciello@dell.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Keith Busch <keith.busch@intel.com>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	linux-nvme <linux-nvme@lists.infradead.org>,
	Linux PM <linux-pm@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Rajat Jain <rajatja@google.com>
Subject: Re: [Regression] Commit "nvme/pci: Use host managed power state for suspend" has problems
Date: Fri, 26 Jul 2019 02:20:19 +0800	[thread overview]
Message-ID: <46857EDA-081E-4622-A8D7-D337127A38DE@canonical.com> (raw)
In-Reply-To: <CAJZ5v0iDQ4=kTUgW94tKGt7oJzA_3uVU_M6HAMbNCRXwp_do8A@mail.gmail.com>

at 01:03, Rafael J. Wysocki <rafael@kernel.org> wrote:

> On Thu, Jul 25, 2019 at 6:24 PM <Mario.Limonciello@dell.com> wrote:
>> +Rajat
>>
>>> -----Original Message-----
>>> From: Kai-Heng Feng <kai.heng.feng@canonical.com>
>>> Sent: Thursday, July 25, 2019 9:03 AM
>>> To: Rafael J. Wysocki
>>> Cc: Keith Busch; Christoph Hellwig; Sagi Grimberg; linux-
>>> nvme@lists.infradead.org; Limonciello, Mario; Linux PM; LKML
>>> Subject: Re: [Regression] Commit "nvme/pci: Use host managed power  
>>> state for
>>> suspend" has problems
>>>
>>>
>>> [EXTERNAL EMAIL]
>>>
>>> Hi Rafael,
>>>
>>> at 17:51, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
>>>
>>>> Hi Keith,
>>>>
>>>> Unfortunately,
>>>>
>>>> commit d916b1be94b6dc8d293abed2451f3062f6af7551
>>>> Author: Keith Busch <keith.busch@intel.com>
>>>> Date:   Thu May 23 09:27:35 2019 -0600
>>>>
>>>>     nvme-pci: use host managed power state for suspend
>>>>
>>>> doesn't universally improve things.  In fact, in some cases it makes
>>>> things worse.
>>>>
>>>> For example, on the Dell XPS13 9380 I have here it prevents the  
>>>> processor
>>>> package
>>>> from reaching idle states deeper than PC2 in suspend-to-idle (which, of
>>>> course, also
>>>> prevents the SoC from reaching any kind of S0ix).
>>>>
>>>> That can be readily explained too.  Namely, with the commit above the
>>>> NVMe device
>>>> stays in D0 over suspend/resume, so the root port it is connected to  
>>>> also
>>>> has to stay in
>>>> D0 and that "blocks" package C-states deeper than PC2.
>>>>
>>>> In order for the root port to be able to go to D3, the device connected
>>>> to it also needs
>>>> to go into D3, so it looks like (at least on this particular machine,  
>>>> but
>>>> maybe in
>>>> general), both D3 and the NVMe-specific PM are needed.
>>
>> Well this is really unfortunate to hear.  I recall that with some disks  
>> we were
>> seeing problems where NVME specific PM wasn't working when the disk was  
>> in D3.
>>
>> On your specific disk, it would be good to know if just removing the  
>> pci_save_state(pdev)
>> call helps.
>
> Yes, it does help.
>
>> If so, :
>> * that might be a better option to add as a parameter.
>> * maybe we should double check all the disks one more time with that  
>> tweak.
>
> At this point it seems so.
>
>>>> I'm not sure what to do here, because evidently there are systems where
>>>> that commit
>>>> helps.  I was thinking about adding a module option allowing the user to
>>>> override the
>>>> default behavior which in turn should be compatible with 5.2 and earlier
>>>> kernels.
>>>
>>> I just briefly tested s2i on XPS 9370, and the power meter shows a  
>>> 0.8~0.9W
>>> power consumption so at least I don’t see the issue on XPS 9370.
>>
>> To me that confirms NVME is down, but it still seems higher than I would  
>> have
>> expected.  We should be more typically in the order of ~0.3W I think.

 From what I’ve observed, ~0.8W s2idle is already better than Windows (~1W).
0.3W is what I see during S5.

>
> It may go to PC10, but not reach S0ix.
>
> Anyway, I run the s2idle tests under turbostat which then tells me
> what has happened more precisely.

The XPS 9370 at my hand does reach to s0ix during s2idle:
# cat /sys/kernel/debug/pmc_core/slp_s0_residency_usec
15998400

So I think keep the root port in D0 is not the culprit here.
Maybe something is wrong on the ASPM settings?

Kai-Heng

  parent reply	other threads:[~2019-07-25 18:20 UTC|newest]

Thread overview: 75+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-25  9:51 Rafael J. Wysocki
2019-07-25 14:02 ` Kai-Heng Feng
2019-07-25 16:23   ` Mario.Limonciello
2019-07-25 17:03     ` Rafael J. Wysocki
2019-07-25 17:23       ` Mario.Limonciello
2019-07-25 18:20       ` Kai-Heng Feng [this message]
2019-07-25 19:09         ` Mario.Limonciello
2019-07-30 10:45       ` Rafael J. Wysocki
2019-07-30 14:41         ` Keith Busch
2019-07-30 17:14           ` Mario.Limonciello
2019-07-30 18:50             ` Kai-Heng Feng
2019-07-30 19:19               ` Keith Busch
2019-07-30 21:05                 ` Mario.Limonciello
2019-07-30 21:31                   ` Keith Busch
2019-07-31 21:25                     ` Rafael J. Wysocki
2019-07-31 22:19                       ` Keith Busch
2019-07-31 22:33                         ` Rafael J. Wysocki
2019-08-01  9:05                           ` Kai-Heng Feng
2019-08-01 17:29                             ` Rafael J. Wysocki
2019-08-01 19:05                               ` Mario.Limonciello
2019-08-01 22:26                                 ` Rafael J. Wysocki
2019-08-02 10:55                                   ` Kai-Heng Feng
2019-08-02 11:04                                     ` Rafael J. Wysocki
2019-08-05 19:13                                       ` Kai-Heng Feng
2019-08-05 21:28                                         ` Rafael J. Wysocki
2019-08-06 14:02                                           ` Mario.Limonciello
2019-08-06 15:00                                             ` Rafael J. Wysocki
2019-08-07 10:29                                               ` Rafael J. Wysocki
2019-08-01 20:22                             ` Keith Busch
2019-08-07  9:48                         ` Rafael J. Wysocki
2019-08-07 10:45                           ` Christoph Hellwig
2019-08-07 10:54                             ` Rafael J. Wysocki
2019-08-07  9:53                         ` [PATCH] nvme-pci: Do not prevent PCI bus-level PM from being used Rafael J. Wysocki
2019-08-07 10:14                           ` Rafael J. Wysocki
2019-08-07 10:43                           ` Christoph Hellwig
2019-08-07 14:37                           ` Keith Busch
2019-08-08  8:36                         ` [PATCH] nvme-pci: Allow PCI bus-level PM to be used if ASPM is disabled Rafael J. Wysocki
2019-08-08  8:48                           ` Christoph Hellwig
2019-08-08  9:06                             ` Rafael J. Wysocki
2019-08-08 10:03                         ` [PATCH v2 0/2] " Rafael J. Wysocki
2019-08-08 10:06                           ` [PATCH v2 1/2] PCI: PCIe: ASPM: Introduce pcie_aspm_enabled_mask() Rafael J. Wysocki
2019-08-08 13:15                             ` Bjorn Helgaas
2019-08-08 14:48                               ` Rafael J. Wysocki
2019-08-08 10:10                           ` [PATCH v2 2/2] nvme-pci: Allow PCI bus-level PM to be used if ASPM is disabled Rafael J. Wysocki
2019-08-08 13:43                             ` Bjorn Helgaas
2019-08-08 14:47                               ` Rafael J. Wysocki
2019-08-08 17:06                                 ` Rafael J. Wysocki
2019-08-08 18:39                                 ` Bjorn Helgaas
2019-08-08 20:01                                   ` Keith Busch
2019-08-08 20:05                                   ` Mario.Limonciello
2019-08-08 20:41                                   ` Rafael J. Wysocki
2019-08-09  4:47                                     ` Bjorn Helgaas
2019-08-09  8:04                                       ` Rafael J. Wysocki
2019-08-08 21:51                         ` [PATCH v3 0/2] " Rafael J. Wysocki
2019-08-08 21:55                           ` [PATCH v3 1/2] PCI: PCIe: ASPM: Introduce pcie_aspm_enabled() Rafael J. Wysocki
2019-08-09  4:50                             ` Bjorn Helgaas
2019-08-09  8:00                               ` Rafael J. Wysocki
2019-10-07 22:34                             ` Bjorn Helgaas
2019-10-08  9:27                               ` Rafael J. Wysocki
2019-10-08 21:16                                 ` Bjorn Helgaas
2019-10-08 22:54                                   ` Rafael J. Wysocki
2019-10-09 12:49                                     ` Bjorn Helgaas
2019-08-08 21:58                           ` [PATCH v3 2/2] nvme-pci: Allow PCI bus-level PM to be used if ASPM is disabled Rafael J. Wysocki
2019-08-08 22:13                           ` [PATCH v3 0/2] " Keith Busch
2019-08-09  8:05                             ` Rafael J. Wysocki
2019-08-09 14:52                               ` Keith Busch
2019-07-25 16:59   ` [Regression] Commit "nvme/pci: Use host managed power state for suspend" has problems Rafael J. Wysocki
2019-07-25 14:52 ` Keith Busch
2019-07-25 19:48   ` Rafael J. Wysocki
2019-07-25 19:52     ` Keith Busch
2019-07-25 20:02       ` Rafael J. Wysocki
2019-07-26 14:02         ` Kai-Heng Feng
2019-07-27 12:55           ` Rafael J. Wysocki
2019-07-29 15:51             ` Mario.Limonciello
2019-07-29 22:05               ` Rafael J. Wysocki

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=46857EDA-081E-4622-A8D7-D337127A38DE@canonical.com \
    --to=kai.heng.feng@canonical.com \
    --cc=Mario.Limonciello@dell.com \
    --cc=hch@lst.de \
    --cc=keith.busch@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nvme@lists.infradead.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=rafael@kernel.org \
    --cc=rajatja@google.com \
    --cc=rjw@rjwysocki.net \
    --cc=sagi@grimberg.me \
    --subject='Re: [Regression] Commit "nvme/pci: Use host managed power state for suspend" has problems' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).