Re: [PATCH 0/8] Cpufreq, cpu hotplug, suspend/resume related fixes

[Lan Tianyu <tianyu.lan@intel.com>]

On 2013年07月12日 06:15, Srivatsa S. Bhat wrote:
> 
> Hi,
> 
> Commit a66b2e (cpufreq: Preserve sysfs files across suspend/resume) caused
> some subtle regressions in the cpufreq subsystem during suspend/resume.
> This patchset is aimed at rectifying those problems, by fixing the regression
> as well as achieving the original goal of that commit in a proper way.
> 
> Patch 1 reverts the above commit, and is CC'ed to stable.
> 
> Patches 2 - 5 reorganize the code and have no functional impact, and can go
> in as general cleanups as well. This reorganization builds a base that the
> rest of the patches will make use of.
> 
> Patch 6 and 7 add a mechanism to perform light-weight init/tear-down of CPUs
> in the cpufreq subsystem and finally patch 8 uses it to preserve sysfs files
> across suspend/resume.
> 
> All the patches apply on current mainline.
> 
> 
> Robert, Durgadoss, it would be great if you could try it out and see if it works
> well for your usecase. I tested it locally and cpufreq related files did retain
> their permissions across suspend/resume. Let me know if it works fine in your
> setup too.
> 
> And I'd of course appreciate to hear from Dirk, Tianyu and Toralf to know
> whether their systems work fine after:
> a. applying only the first commit (this is what gets backported to stable)
> b. applying all the commits

Hi, I tested this patchset on my machine and the issue in bug 59781 has
been resolved.

Tested-by: Tianyu Lan <tianyu.lan@intel.com>


> 
> (Note: I had to use Michael's fix[1] to avoid CPU hotplug deadlock while
> testing this patchset. Though that patch also touches cpufreq subsystem, it
> doesn't affect this patchset in any way and there is absolutely no dependency
> between the two in terms of code. That fix just makes basic CPU hotplug work
> without locking up on current mainline).
> 
> [1]. https://lkml.org/lkml/2013/7/10/611
> 
> 
> Thank you very much!
> 
> 
>  Srivatsa S. Bhat (8):
>       cpufreq: Revert commit a66b2e to fix cpufreq regression during suspend/resume
>       cpufreq: Fix misplaced call to cpufreq_update_policy()
>       cpufreq: Add helper to perform alloc/free of policy structure
>       cpufreq: Extract non-interface related stuff from cpufreq_add_dev_interface
>       cpufreq: Extract the handover of policy cpu to a helper function
>       cpufreq: Introduce a flag ('frozen') to separate full vs temporary init/teardown
>       cpufreq: Preserve policy structure across suspend/resume
>       cpufreq: Perform light-weight init/teardown during suspend/resume
> 
>  drivers/cpufreq/cpufreq.c       |  297 ++++++++++++++++++++++++++-------------
>  drivers/cpufreq/cpufreq_stats.c |   10 -
>  2 files changed, 199 insertions(+), 108 deletions(-)
> 
> 
> Thanks,
> Srivatsa S. Bhat
> IBM Linux Technology Center
> 


-- 
Best regards
Tianyu Lan