diff mbox series

[2/4] hwmon: Use subdir-ccflags-* to inherit debug flag

Message ID 1612518255-23052-3-git-send-email-yangyicong@hisilicon.com (mailing list archive)
State New
Headers show
Series Use subdir-ccflags-* to inherit debug flag | expand

Commit Message

Yicong Yang Feb. 5, 2021, 9:44 a.m. UTC
From: Junhao He <hejunhao2@hisilicon.com>

Use subdir-ccflags-* instead of ccflags-* to inherit the debug
settings from Kconfig when traversing subdirectories.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Junhao He <hejunhao2@hisilicon.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
---
 drivers/hwmon/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Guenter Roeck Feb. 5, 2021, 6:28 p.m. UTC | #1
On Fri, Feb 05, 2021 at 05:44:13PM +0800, Yicong Yang wrote:
> From: Junhao He <hejunhao2@hisilicon.com>
> 
> Use subdir-ccflags-* instead of ccflags-* to inherit the debug
> settings from Kconfig when traversing subdirectories.
> 
> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
> Signed-off-by: Junhao He <hejunhao2@hisilicon.com>
> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>

What problem does this fix ? Maybe I am missing it, but I don't see
DEBUG being used in a subdirectory of drivers/hwmon.

Guenter

> ---
>  drivers/hwmon/Makefile | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 09a86c5..1c0c089 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -201,5 +201,5 @@ obj-$(CONFIG_SENSORS_XGENE)	+= xgene-hwmon.o
>  obj-$(CONFIG_SENSORS_OCC)	+= occ/
>  obj-$(CONFIG_PMBUS)		+= pmbus/
>  
> -ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
> +subdir-ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
>  
> -- 
> 2.8.1
>
Bjorn Helgaas Feb. 5, 2021, 8:08 p.m. UTC | #2
On Fri, Feb 05, 2021 at 10:28:32AM -0800, Guenter Roeck wrote:
> On Fri, Feb 05, 2021 at 05:44:13PM +0800, Yicong Yang wrote:
> > From: Junhao He <hejunhao2@hisilicon.com>
> > 
> > Use subdir-ccflags-* instead of ccflags-* to inherit the debug
> > settings from Kconfig when traversing subdirectories.
> > 
> > Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
> > Signed-off-by: Junhao He <hejunhao2@hisilicon.com>
> > Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
> 
> What problem does this fix ? Maybe I am missing it, but I don't see
> DEBUG being used in a subdirectory of drivers/hwmon.

It's my fault for raising this question [1].  Yicong fixed a real
problem in drivers/pci, where we are currently using

  ccflags-$(CONFIG_PCI_DEBUG) := -DDEBUG

so CONFIG_PCI_DEBUG=y turns on debug in drivers/pci, but not in the
subdirectories.  That's surprising to users.

So my question was whether we should default to using subdir-ccflags
for -DDEBUG in general, and only use ccflags when we have
subdirectories that have their own debug options, e.g.,

  drivers/i2c/Makefile:ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG
  drivers/i2c/algos/Makefile:ccflags-$(CONFIG_I2C_DEBUG_ALGO) := -DDEBUG
  drivers/i2c/busses/Makefile:ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
  drivers/i2c/muxes/Makefile:ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG

I mentioned drivers/hwmon along with a few others that have
subdirectories, do not have per-subdirectory debug options, and use
ccflags.  I didn't try to determine whether those subdirectories
currently use -DDEBUG.

In the case of drivers/hwmon, several drivers do use pr_debug(),
and CONFIG_HWMON_DEBUG_CHIP=y turns those on.  But if somebody
were to add pr_debug() to drivers/hwmon/occ/common.c, for example,
CONFIG_HWMON_DEBUG_CHIP=y would *not* turn it on.  That sounds
surprising to me, but if that's what you intend, that's totally fine.

[1] https://lore.kernel.org/r/20210204161048.GA68790@bjorn-Precision-5520

> > ---
> >  drivers/hwmon/Makefile | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> > index 09a86c5..1c0c089 100644
> > --- a/drivers/hwmon/Makefile
> > +++ b/drivers/hwmon/Makefile
> > @@ -201,5 +201,5 @@ obj-$(CONFIG_SENSORS_XGENE)	+= xgene-hwmon.o
> >  obj-$(CONFIG_SENSORS_OCC)	+= occ/
> >  obj-$(CONFIG_PMBUS)		+= pmbus/
> >  
> > -ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
> > +subdir-ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
> >  
> > -- 
> > 2.8.1
> >
Yicong Yang Feb. 8, 2021, 10:51 a.m. UTC | #3
On 2021/2/6 4:08, Bjorn Helgaas wrote:
> On Fri, Feb 05, 2021 at 10:28:32AM -0800, Guenter Roeck wrote:
>> On Fri, Feb 05, 2021 at 05:44:13PM +0800, Yicong Yang wrote:
>>> From: Junhao He <hejunhao2@hisilicon.com>
>>>
>>> Use subdir-ccflags-* instead of ccflags-* to inherit the debug
>>> settings from Kconfig when traversing subdirectories.
>>>
>>> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
>>> Signed-off-by: Junhao He <hejunhao2@hisilicon.com>
>>> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
>>
>> What problem does this fix ? Maybe I am missing it, but I don't see
>> DEBUG being used in a subdirectory of drivers/hwmon.
> 
> It's my fault for raising this question [1].  Yicong fixed a real
> problem in drivers/pci, where we are currently using
> 
>   ccflags-$(CONFIG_PCI_DEBUG) := -DDEBUG
> 
> so CONFIG_PCI_DEBUG=y turns on debug in drivers/pci, but not in the
> subdirectories.  That's surprising to users.
> 
> So my question was whether we should default to using subdir-ccflags
> for -DDEBUG in general, and only use ccflags when we have
> subdirectories that have their own debug options, e.g.,
> 
>   drivers/i2c/Makefile:ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG
>   drivers/i2c/algos/Makefile:ccflags-$(CONFIG_I2C_DEBUG_ALGO) := -DDEBUG
>   drivers/i2c/busses/Makefile:ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
>   drivers/i2c/muxes/Makefile:ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
> 
> I mentioned drivers/hwmon along with a few others that have
> subdirectories, do not have per-subdirectory debug options, and use
> ccflags.  I didn't try to determine whether those subdirectories
> currently use -DDEBUG.
> 
> In the case of drivers/hwmon, several drivers do use pr_debug(),
> and CONFIG_HWMON_DEBUG_CHIP=y turns those on.  But if somebody
> were to add pr_debug() to drivers/hwmon/occ/common.c, for example,
> CONFIG_HWMON_DEBUG_CHIP=y would *not* turn it on.  That sounds
> surprising to me, but if that's what you intend, that's totally fine.

i thought CONFIG_HWMON_DEBUG_CHIP=y means to enable debug including the
subdirectories, so use subdir-ccflags-* will make sure the debug
message on in the subdirectories, if there will be.

please let me know if i understand wrong.

Thanks,
Yicong

> 
> [1] https://lore.kernel.org/r/20210204161048.GA68790@bjorn-Precision-5520
> 
>>> ---
>>>  drivers/hwmon/Makefile | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
>>> index 09a86c5..1c0c089 100644
>>> --- a/drivers/hwmon/Makefile
>>> +++ b/drivers/hwmon/Makefile
>>> @@ -201,5 +201,5 @@ obj-$(CONFIG_SENSORS_XGENE)	+= xgene-hwmon.o
>>>  obj-$(CONFIG_SENSORS_OCC)	+= occ/
>>>  obj-$(CONFIG_PMBUS)		+= pmbus/
>>>  
>>> -ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
>>> +subdir-ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
>>>  
>>> -- 
>>> 2.8.1
>>>
> 
> .
>
Guenter Roeck Feb. 8, 2021, 9 p.m. UTC | #4
On 2/5/21 12:08 PM, Bjorn Helgaas wrote:
> On Fri, Feb 05, 2021 at 10:28:32AM -0800, Guenter Roeck wrote:
>> On Fri, Feb 05, 2021 at 05:44:13PM +0800, Yicong Yang wrote:
>>> From: Junhao He <hejunhao2@hisilicon.com>
>>>
>>> Use subdir-ccflags-* instead of ccflags-* to inherit the debug
>>> settings from Kconfig when traversing subdirectories.
>>>
>>> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
>>> Signed-off-by: Junhao He <hejunhao2@hisilicon.com>
>>> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
>>
>> What problem does this fix ? Maybe I am missing it, but I don't see
>> DEBUG being used in a subdirectory of drivers/hwmon.
> 
> It's my fault for raising this question [1].  Yicong fixed a real
> problem in drivers/pci, where we are currently using
> 
>   ccflags-$(CONFIG_PCI_DEBUG) := -DDEBUG
> 
> so CONFIG_PCI_DEBUG=y turns on debug in drivers/pci, but not in the
> subdirectories.  That's surprising to users.
> 
> So my question was whether we should default to using subdir-ccflags
> for -DDEBUG in general, and only use ccflags when we have
> subdirectories that have their own debug options, e.g.,
> 
>   drivers/i2c/Makefile:ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG
>   drivers/i2c/algos/Makefile:ccflags-$(CONFIG_I2C_DEBUG_ALGO) := -DDEBUG
>   drivers/i2c/busses/Makefile:ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
>   drivers/i2c/muxes/Makefile:ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
> 
> I mentioned drivers/hwmon along with a few others that have
> subdirectories, do not have per-subdirectory debug options, and use
> ccflags.  I didn't try to determine whether those subdirectories
> currently use -DDEBUG.
> 
> In the case of drivers/hwmon, several drivers do use pr_debug(),
> and CONFIG_HWMON_DEBUG_CHIP=y turns those on.  But if somebody
> were to add pr_debug() to drivers/hwmon/occ/common.c, for example,
> CONFIG_HWMON_DEBUG_CHIP=y would *not* turn it on.  That sounds
> surprising to me, but if that's what you intend, that's totally fine.
> 

That does make sense, but that explanation is missing from the
description.

Guenter

> [1] https://lore.kernel.org/r/20210204161048.GA68790@bjorn-Precision-5520
> 
>>> ---
>>>  drivers/hwmon/Makefile | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
>>> index 09a86c5..1c0c089 100644
>>> --- a/drivers/hwmon/Makefile
>>> +++ b/drivers/hwmon/Makefile
>>> @@ -201,5 +201,5 @@ obj-$(CONFIG_SENSORS_XGENE)	+= xgene-hwmon.o
>>>  obj-$(CONFIG_SENSORS_OCC)	+= occ/
>>>  obj-$(CONFIG_PMBUS)		+= pmbus/
>>>  
>>> -ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
>>> +subdir-ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
>>>  
>>> -- 
>>> 2.8.1
>>>
diff mbox series

Patch

diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 09a86c5..1c0c089 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -201,5 +201,5 @@  obj-$(CONFIG_SENSORS_XGENE)	+= xgene-hwmon.o
 obj-$(CONFIG_SENSORS_OCC)	+= occ/
 obj-$(CONFIG_PMBUS)		+= pmbus/
 
-ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG
+subdir-ccflags-$(CONFIG_HWMON_DEBUG_CHIP) := -DDEBUG