[v4] x86: Cleanups around slow_down_io()

[PATCH v4 0/6] x86: Cleanups around slow_down_io()

Posted by Juergen Gross 4 months, 3 weeks ago

While looking at paravirt cleanups I stumbled over slow_down_io() and
the related REALLY_SLOW_IO define.

Do several cleanups, resulting in a deletion of REALLY_SLOW_IO and the
io_delay() paravirt function hook.

Patch 4 is removing the config options for selecting the default delay
mechanism and sets the default to "no delay". This is in preparation of
removing the io_delay() functionality completely, as suggested by Ingo
Molnar.

Patch 5 is adding an additional config option allowing to avoid
building io_delay.c (default is still to build it).

Changes in V2:
- patches 2 and 3 of V1 have been applied
- new patches 4 and 5

Changes in V3:
- rebase to tip/master kernel branch

Changes in V4:
- add patch 1 as prereq patch to the series

Juergen Gross (6):
  x86/irqflags: Fix build failure
  x86/paravirt: Replace io_delay() hook with a bool
  block/floppy: Don't use REALLY_SLOW_IO for delays
  x86/io: Remove REALLY_SLOW_IO handling
  x86/io_delay: Switch io_delay() default mechanism to "none"
  x86/io_delay: Add config option for controlling build of io_delay.

 arch/x86/Kconfig                      |  8 +++
 arch/x86/Kconfig.debug                | 30 ----------
 arch/x86/include/asm/floppy.h         | 31 ++++++++--
 arch/x86/include/asm/io.h             | 19 ++++---
 arch/x86/include/asm/irqflags.h       |  6 +-
 arch/x86/include/asm/paravirt-base.h  |  6 ++
 arch/x86/include/asm/paravirt.h       | 11 ----
 arch/x86/include/asm/paravirt_types.h |  2 -
 arch/x86/kernel/Makefile              |  3 +-
 arch/x86/kernel/cpu/vmware.c          |  2 +-
 arch/x86/kernel/io_delay.c            | 81 +--------------------------
 arch/x86/kernel/kvm.c                 |  8 +--
 arch/x86/kernel/paravirt.c            |  3 +-
 arch/x86/kernel/setup.c               |  4 +-
 arch/x86/xen/enlighten_pv.c           |  6 +-
 drivers/block/floppy.c                |  2 -
 16 files changed, 63 insertions(+), 159 deletions(-)

-- 
2.52.0

Re: [PATCH v4 0/6] x86: Cleanups around slow_down_io()

Posted by Juergen Gross 3 months ago

On 19.01.26 19:26, Juergen Gross wrote:
> While looking at paravirt cleanups I stumbled over slow_down_io() and
> the related REALLY_SLOW_IO define.
> 
> Do several cleanups, resulting in a deletion of REALLY_SLOW_IO and the
> io_delay() paravirt function hook.
> 
> Patch 4 is removing the config options for selecting the default delay
> mechanism and sets the default to "no delay". This is in preparation of
> removing the io_delay() functionality completely, as suggested by Ingo
> Molnar.
> 
> Patch 5 is adding an additional config option allowing to avoid
> building io_delay.c (default is still to build it).
> 
> Changes in V2:
> - patches 2 and 3 of V1 have been applied
> - new patches 4 and 5
> 
> Changes in V3:
> - rebase to tip/master kernel branch
> 
> Changes in V4:
> - add patch 1 as prereq patch to the series
> 
> Juergen Gross (6):
>    x86/irqflags: Fix build failure
>    x86/paravirt: Replace io_delay() hook with a bool
>    block/floppy: Don't use REALLY_SLOW_IO for delays
>    x86/io: Remove REALLY_SLOW_IO handling
>    x86/io_delay: Switch io_delay() default mechanism to "none"
>    x86/io_delay: Add config option for controlling build of io_delay.
> 
>   arch/x86/Kconfig                      |  8 +++
>   arch/x86/Kconfig.debug                | 30 ----------
>   arch/x86/include/asm/floppy.h         | 31 ++++++++--
>   arch/x86/include/asm/io.h             | 19 ++++---
>   arch/x86/include/asm/irqflags.h       |  6 +-
>   arch/x86/include/asm/paravirt-base.h  |  6 ++
>   arch/x86/include/asm/paravirt.h       | 11 ----
>   arch/x86/include/asm/paravirt_types.h |  2 -
>   arch/x86/kernel/Makefile              |  3 +-
>   arch/x86/kernel/cpu/vmware.c          |  2 +-
>   arch/x86/kernel/io_delay.c            | 81 +--------------------------
>   arch/x86/kernel/kvm.c                 |  8 +--
>   arch/x86/kernel/paravirt.c            |  3 +-
>   arch/x86/kernel/setup.c               |  4 +-
>   arch/x86/xen/enlighten_pv.c           |  6 +-
>   drivers/block/floppy.c                |  2 -
>   16 files changed, 63 insertions(+), 159 deletions(-)
> 

Any comments?


Juergen

Re: [PATCH v4 0/6] x86: Cleanups around slow_down_io()

Posted by Juergen Gross 4 months ago

PING?

Now 3 weeks without any reaction...

On 19.01.26 19:26, Juergen Gross wrote:
> While looking at paravirt cleanups I stumbled over slow_down_io() and
> the related REALLY_SLOW_IO define.
> 
> Do several cleanups, resulting in a deletion of REALLY_SLOW_IO and the
> io_delay() paravirt function hook.
> 
> Patch 4 is removing the config options for selecting the default delay
> mechanism and sets the default to "no delay". This is in preparation of
> removing the io_delay() functionality completely, as suggested by Ingo
> Molnar.
> 
> Patch 5 is adding an additional config option allowing to avoid
> building io_delay.c (default is still to build it).
> 
> Changes in V2:
> - patches 2 and 3 of V1 have been applied
> - new patches 4 and 5
> 
> Changes in V3:
> - rebase to tip/master kernel branch
> 
> Changes in V4:
> - add patch 1 as prereq patch to the series
> 
> Juergen Gross (6):
>    x86/irqflags: Fix build failure
>    x86/paravirt: Replace io_delay() hook with a bool
>    block/floppy: Don't use REALLY_SLOW_IO for delays
>    x86/io: Remove REALLY_SLOW_IO handling
>    x86/io_delay: Switch io_delay() default mechanism to "none"
>    x86/io_delay: Add config option for controlling build of io_delay.
> 
>   arch/x86/Kconfig                      |  8 +++
>   arch/x86/Kconfig.debug                | 30 ----------
>   arch/x86/include/asm/floppy.h         | 31 ++++++++--
>   arch/x86/include/asm/io.h             | 19 ++++---
>   arch/x86/include/asm/irqflags.h       |  6 +-
>   arch/x86/include/asm/paravirt-base.h  |  6 ++
>   arch/x86/include/asm/paravirt.h       | 11 ----
>   arch/x86/include/asm/paravirt_types.h |  2 -
>   arch/x86/kernel/Makefile              |  3 +-
>   arch/x86/kernel/cpu/vmware.c          |  2 +-
>   arch/x86/kernel/io_delay.c            | 81 +--------------------------
>   arch/x86/kernel/kvm.c                 |  8 +--
>   arch/x86/kernel/paravirt.c            |  3 +-
>   arch/x86/kernel/setup.c               |  4 +-
>   arch/x86/xen/enlighten_pv.c           |  6 +-
>   drivers/block/floppy.c                |  2 -
>   16 files changed, 63 insertions(+), 159 deletions(-)
>

Re: [PATCH v4 0/6] x86: Cleanups around slow_down_io()

Posted by Borislav Petkov 4 months ago

On Mon, Feb 09, 2026 at 10:11:49AM +0100, Juergen Gross wrote:
> PING?
> 
> Now 3 weeks without any reaction...

Jürgen, there are other patchsets that need review too. And we have merge
window right now so no reviewing anyway.

And you know all that damn well!

How about you help us out and you start reviewing x86 patches instead of
pinging every week?

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v4 0/6] x86: Cleanups around slow_down_io()

Posted by Juergen Gross 4 months, 1 week ago

Ping?

On 19.01.26 19:26, Juergen Gross wrote:
> While looking at paravirt cleanups I stumbled over slow_down_io() and
> the related REALLY_SLOW_IO define.
> 
> Do several cleanups, resulting in a deletion of REALLY_SLOW_IO and the
> io_delay() paravirt function hook.
> 
> Patch 4 is removing the config options for selecting the default delay
> mechanism and sets the default to "no delay". This is in preparation of
> removing the io_delay() functionality completely, as suggested by Ingo
> Molnar.
> 
> Patch 5 is adding an additional config option allowing to avoid
> building io_delay.c (default is still to build it).
> 
> Changes in V2:
> - patches 2 and 3 of V1 have been applied
> - new patches 4 and 5
> 
> Changes in V3:
> - rebase to tip/master kernel branch
> 
> Changes in V4:
> - add patch 1 as prereq patch to the series
> 
> Juergen Gross (6):
>    x86/irqflags: Fix build failure
>    x86/paravirt: Replace io_delay() hook with a bool
>    block/floppy: Don't use REALLY_SLOW_IO for delays
>    x86/io: Remove REALLY_SLOW_IO handling
>    x86/io_delay: Switch io_delay() default mechanism to "none"
>    x86/io_delay: Add config option for controlling build of io_delay.
> 
>   arch/x86/Kconfig                      |  8 +++
>   arch/x86/Kconfig.debug                | 30 ----------
>   arch/x86/include/asm/floppy.h         | 31 ++++++++--
>   arch/x86/include/asm/io.h             | 19 ++++---
>   arch/x86/include/asm/irqflags.h       |  6 +-
>   arch/x86/include/asm/paravirt-base.h  |  6 ++
>   arch/x86/include/asm/paravirt.h       | 11 ----
>   arch/x86/include/asm/paravirt_types.h |  2 -
>   arch/x86/kernel/Makefile              |  3 +-
>   arch/x86/kernel/cpu/vmware.c          |  2 +-
>   arch/x86/kernel/io_delay.c            | 81 +--------------------------
>   arch/x86/kernel/kvm.c                 |  8 +--
>   arch/x86/kernel/paravirt.c            |  3 +-
>   arch/x86/kernel/setup.c               |  4 +-
>   arch/x86/xen/enlighten_pv.c           |  6 +-
>   drivers/block/floppy.c                |  2 -
>   16 files changed, 63 insertions(+), 159 deletions(-)
>