Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1590242

Re: [PATCH v2 1/4] Revert"x86/acpi: Set persistent cpuid <-> nodeid mapping when booting"

Show all headers | View raw

On Mon, 20 Feb 2017, Dou Liyang wrote:

> Currently, We make the mapping of "cpuid <-> nodeid" fixed at the booting time.
> It keeps consistent with the WorkQueue and avoids some bugs which may be caused
> by the dynamic assignment.
> 
> But, The ACPI table is unreliable and it is very risky that we use the entity
> which isn't related to a physical device at booting time.
> 
> Now, we revert our patches. Do the last mapping of "cpuid <-> nodeid" at
> hot-plug time, not at booting time where we did some useless work.
> It also can make the mapping of "cpuid <-> nodeid" fixed and avoid excessive
> use of the ACPI table.
> 
> The patch revert the commit dc6db24d24:
>   "x86/acpi: Set persistent cpuid <-> nodeid mapping when booting".

That changelog needs some massaging. Something like this:

  The mapping of "cpuid <-> nodeid" is established at boot time via ACPI
  tables to keep associations of workqueues and other node related items
  consistent across cpu hotplug.

  But, ACPI tables are unreliable and failures with that boot time mapping
  have been reported on machines where the ACPI table and the physical
  information which is retrieved at actual hotplug is inconsistent.

  Revert the mapping implementation so it can be replaced with a less error
  prone approach.

This clearly describes:

  1) The context

  2) The problem

  3) The solution (revert)

You don't have to explain what the new solution will be in the changelog of
the revert. For the revert it's only relevant WHY we do the revert.

Please avoid writing changelogs in 'we' form. Write it pure technical, like
a manual.

Also avoid phrases like: "The patch/This patch". We all know already that
this is a patch, otherwise it wouldn't have been sent.

Documentation/process/submitting-patches.rst says:

  Describe your changes in imperative mood, e.g. "make xyzzy do frotz"
  instead of "[This patch] makes xyzzy do frotz" or "[I] changed xyzzy
  to do frotz", as if you are giving orders to the codebase to change
  its behaviour.

Thanks,

	tglx

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v2 0/4] Revert works for the mapping of cpuid <-> nodeid Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-02-20 09:50 +0100
  [PATCH v2 3/4] acpi: Fix the check handle in case of declaring processors using the Device operator Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-02-20 09:50 +0100
    Re: [PATCH v2 3/4] acpi: Fix the check handle in case of declaring  processors using the Device operator Thomas Gleixner <tglx@linutronix.de> - 2017-03-01 13:40 +0100
      Re: [PATCH v2 3/4] acpi: Fix the check handle in case of declaring  processors using the Device operator Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-03-02 09:20 +0100
  [PATCH v2 1/4] Revert"x86/acpi: Set persistent cpuid <-> nodeid mapping when booting" Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-02-20 09:50 +0100
    Re: [PATCH v2 1/4] Revert"x86/acpi: Set persistent cpuid <-> nodeid  mapping when booting" Thomas Gleixner <tglx@linutronix.de> - 2017-03-01 12:00 +0100
      Re: [PATCH v2 1/4] Revert"x86/acpi: Set persistent cpuid <-> nodeid  mapping when booting" Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-03-02 09:20 +0100
  [PATCH v2 2/4] Revert"x86/acpi: Enable MADT APIs to return disabled apicids" Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-02-20 09:50 +0100
    Re: [PATCH v2 2/4] Revert"x86/acpi: Enable MADT APIs to return  disabled apicids" Thomas Gleixner <tglx@linutronix.de> - 2017-03-01 12:00 +0100
      Re: [PATCH v2 2/4] Revert"x86/acpi: Enable MADT APIs to return  disabled apicids" Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-03-02 09:20 +0100
  Re: [PATCH v2 0/4] Revert works for the mapping of cpuid <-> nodeid Ye Xiaolong <xiaolong.ye@intel.com> - 2017-02-21 02:10 +0100
    Re: [PATCH v2 0/4] Revert works for the mapping of cpuid <-> nodeid Ye Xiaolong <xiaolong.ye@intel.com> - 2017-02-21 08:20 +0100
      Re: [PATCH v2 0/4] Revert works for the mapping of cpuid <-> nodeid Dou Liyang <douly.fnst@cn.fujitsu.com> - 2017-02-22 03:00 +0100

csiph-web