[PATCH v3 00/16] timers: Cleanup delay/sleep related mess

[PATCH v3 00/16] timers: Cleanup delay/sleep related mess

[Anna-Maria Behnsen]

Hi,

a question about which sleeping function should be used in acpi_os_sleep()
started a discussion and examination about the existing documentation and
implementation of functions which insert a sleep/delay.

The result of the discussion was, that the documentation is outdated and
the implemented fsleep() reflects the outdated documentation but doesn't
help to reflect reality which in turns leads to the queue which covers the
following things:

- Split out all timeout and sleep related functions from hrtimer.c and timer.c
  into a separate file

- Update function descriptions of sleep related functions

- Change fsleep() to reflect reality

- Rework all comments or users which obviously rely on the outdated
  documentation as they reference "Documentation/timers/timers-howto.rst"

- Update the outdated documentation and move it into a file with a self
  explaining file name (as there are no more references)

- Remove checkpatch checks which also rely on the outdated documentation

The queue is available here:

  git://git.kernel.org/pub/scm/linux/kernel/git/anna-maria/linux-devel.git timers/misc

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
---
Changes in v3:
- Add review remarks
- Split checkpatch patch: 1. Remove links to outdated documentation,
  2. Remove checks in checkpatch which rely on outdated documentation
- Link to v2: https://lore.kernel.org/r/20240911-devel-anna-maria-b4-timers-flseep-v2-0-b0d3f33ccfe0@linutronix.de

Changes in v2:
- change udelay() and ndelay() as suggested by Thomas
- Update some formatting in the new sleep_timeout.c file
- minor typo changes and other small review remarks

Thanks,

        Anna-Maria

---
Anna-Maria Behnsen (16):
      MAINTAINERS: Add missing file include/linux/delay.h
      timers: Move *sleep*() and timeout functions into a separate file
      timers: Update schedule_[hr]timeout*() related function descriptions
      timers: Rename usleep_idle_range() to usleep_range_idle()
      timers: Update function descriptions of sleep/delay related functions
      delay: Rework udelay and ndelay
      timers: Adjust flseep() to reflect reality
      mm/damon/core: Use generic upper bound recommondation for usleep_range()
      timers: Add a warning to usleep_range_state() for wrong order of arguments
      checkpatch: Remove links to outdated documentation
      regulator: core: Use fsleep() to get best sleep mechanism
      iopoll/regmap/phy/snd: Fix comment referencing outdated timer documentation
      powerpc/rtas: Use fsleep() to minimize additional sleep duration
      media: anysee: Fix and remove outdated comment
      timers/Documentation: Cleanup delay/sleep documentation
      checkpatch: Remove broken sleep/delay related checks

 Documentation/dev-tools/checkpatch.rst         |   6 -
 Documentation/timers/delay_sleep_functions.rst | 121 ++++++++
 Documentation/timers/index.rst                 |   2 +-
 Documentation/timers/timers-howto.rst          | 115 --------
 MAINTAINERS                                    |   2 +
 arch/powerpc/kernel/rtas.c                     |  21 +-
 drivers/media/usb/dvb-usb-v2/anysee.c          |  17 +-
 drivers/regulator/core.c                       |  47 +--
 include/asm-generic/delay.h                    |  96 +++++--
 include/linux/delay.h                          |  79 ++++--
 include/linux/iopoll.h                         |  52 ++--
 include/linux/phy.h                            |   9 +-
 include/linux/regmap.h                         |  38 +--
 kernel/time/Makefile                           |   2 +-
 kernel/time/hrtimer.c                          | 120 --------
 kernel/time/sleep_timeout.c                    | 377 +++++++++++++++++++++++++
 kernel/time/timer.c                            | 192 -------------
 mm/damon/core.c                                |   5 +-
 scripts/checkpatch.pl                          |  38 ---
 sound/soc/sof/ops.h                            |   8 +-
 20 files changed, 704 insertions(+), 643 deletions(-)

[PATCH v3 14/16] media: anysee: Fix and remove outdated comment

[Anna-Maria Behnsen]

anysee driver was transformed to use usbv2 years ago. The comments in
anysee_ctrl_msg() still are referencing the old interfaces where msleep()
was used. The v2 interfaces also changed over the years and with commit
1162c7b383a6 ("[media] dvb_usb_v2: refactor dvb_usbv2_generic_rw()") the
usage of msleep() was gone anyway.

Remove FIXME comment and update also comment before call to
dvb_usbv2_generic_rw_locked().

Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: linux-media@vger.kernel.org
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
v3: Remove FIXME comment completely
---
 drivers/media/usb/dvb-usb-v2/anysee.c | 17 ++++-------------
 1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/drivers/media/usb/dvb-usb-v2/anysee.c b/drivers/media/usb/dvb-usb-v2/anysee.c
index 8699846eb416..bea12cdc85e8 100644
--- a/drivers/media/usb/dvb-usb-v2/anysee.c
+++ b/drivers/media/usb/dvb-usb-v2/anysee.c
@@ -46,24 +46,15 @@ static int anysee_ctrl_msg(struct dvb_usb_device *d,
 
 	dev_dbg(&d->udev->dev, "%s: >>> %*ph\n", __func__, slen, state->buf);
 
-	/* We need receive one message more after dvb_usb_generic_rw due
-	   to weird transaction flow, which is 1 x send + 2 x receive. */
+	/*
+	 * We need receive one message more after dvb_usbv2_generic_rw_locked()
+	 * due to weird transaction flow, which is 1 x send + 2 x receive.
+	 */
 	ret = dvb_usbv2_generic_rw_locked(d, state->buf, sizeof(state->buf),
 			state->buf, sizeof(state->buf));
 	if (ret)
 		goto error_unlock;
 
-	/* TODO FIXME: dvb_usb_generic_rw() fails rarely with error code -32
-	 * (EPIPE, Broken pipe). Function supports currently msleep() as a
-	 * parameter but I would not like to use it, since according to
-	 * Documentation/timers/timers-howto.rst it should not be used such
-	 * short, under < 20ms, sleeps. Repeating failed message would be
-	 * better choice as not to add unwanted delays...
-	 * Fixing that correctly is one of those or both;
-	 * 1) use repeat if possible
-	 * 2) add suitable delay
-	 */
-
 	/* get answer, retry few times if error returned */
 	for (i = 0; i < 3; i++) {
 		/* receive 2nd answer */

-- 
2.39.5

Re: [PATCH v3 14/16] media: anysee: Fix and remove outdated comment

[Frederic Weisbecker]

Le Mon, Oct 14, 2024 at 10:22:31AM +0200, Anna-Maria Behnsen a écrit :
> anysee driver was transformed to use usbv2 years ago. The comments in
> anysee_ctrl_msg() still are referencing the old interfaces where msleep()
> was used. The v2 interfaces also changed over the years and with commit
> 1162c7b383a6 ("[media] dvb_usb_v2: refactor dvb_usbv2_generic_rw()") the
> usage of msleep() was gone anyway.
> 
> Remove FIXME comment and update also comment before call to
> dvb_usbv2_generic_rw_locked().
> 
> Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
> Cc: linux-media@vger.kernel.org
> Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Acked-by: Frederic Weisbecker <frederic@kernel.org>

Re: (subset) [PATCH v3 00/16] timers: Cleanup delay/sleep related mess

[Mark Brown]

On Mon, 14 Oct 2024 10:22:17 +0200, Anna-Maria Behnsen wrote:
> a question about which sleeping function should be used in acpi_os_sleep()
> started a discussion and examination about the existing documentation and
> implementation of functions which insert a sleep/delay.
> 
> The result of the discussion was, that the documentation is outdated and
> the implemented fsleep() reflects the outdated documentation but doesn't
> help to reflect reality which in turns leads to the queue which covers the
> following things:
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next

Thanks!

[11/16] regulator: core: Use fsleep() to get best sleep mechanism
        commit: f20669fbcf99d0e15e94fb50929bb1c41618e197

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Re: (subset) [PATCH v3 00/16] timers: Cleanup delay/sleep related mess

[Anna-Maria Behnsen]

Hi Mark,

Mark Brown <broonie@kernel.org> writes:

> On Mon, 14 Oct 2024 10:22:17 +0200, Anna-Maria Behnsen wrote:
>> a question about which sleeping function should be used in acpi_os_sleep()
>> started a discussion and examination about the existing documentation and
>> implementation of functions which insert a sleep/delay.
>> 
>> The result of the discussion was, that the documentation is outdated and
>> the implemented fsleep() reflects the outdated documentation but doesn't
>> help to reflect reality which in turns leads to the queue which covers the
>> following things:
>> 
>> [...]
>
> Applied to
>
>    https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next
>

Would it be ok for you, if the patch is routed through tip tree? kernel
test robot triggers a warning for htmldoc that there is a reference to
the no longer existing file 'timer-howto.rst':

  https://lore.kernel.org/r/202410161059.a0f6IBwj-lkp@intel.com

Thanks,

	Anna-Maria

Re: (subset) [PATCH v3 00/16] timers: Cleanup delay/sleep related mess

[Mark Brown]

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On Fri, Oct 18, 2024 at 10:06:33AM +0200, Anna-Maria Behnsen wrote:

> Would it be ok for you, if the patch is routed through tip tree? kernel
> test robot triggers a warning for htmldoc that there is a reference to
> the no longer existing file 'timer-howto.rst':

>   https://lore.kernel.org/r/202410161059.a0f6IBwj-lkp@intel.com

It should be fine, worst case we just get a duplicate patch which
doesn't super matter.

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Re: (subset) [PATCH v3 00/16] timers: Cleanup delay/sleep related mess

[Mark Brown]

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On Fri, Oct 18, 2024 at 10:06:33AM +0200, Anna-Maria Behnsen wrote:

> Would it be ok for you, if the patch is routed through tip tree? kernel
> test robot triggers a warning for htmldoc that there is a reference to
> the no longer existing file 'timer-howto.rst':

>   https://lore.kernel.org/r/202410161059.a0f6IBwj-lkp@intel.com

Oh, and for that:

Reviewed-by: Mark Brown <broonie@kernel.org>

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