[v3] intel: igb: igb_ethtool.c: Convert kmap() to kmap_local_page()

[PATCH v3] intel: igb: igb_ethtool.c: Convert kmap() to kmap_local_page()

Posted by Alaa Mohamed 4 years, 2 months ago

Convert kmap() to kmap_local_page()

With kmap_local_page(), the mapping is per thread, CPU local and not
globally visible.

Signed-off-by: Alaa Mohamed <eng.alaamohamedsoliman.am@gmail.com>
---
changes in V2:
	fix kunmap_local path value to take address of the mapped page.
---
changes in V3:
	edit commit message to be clearer
---
 drivers/net/ethernet/intel/igb/igb_ethtool.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c
index 2a5782063f4c..c14fc871dd41 100644
--- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
+++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
@@ -1798,14 +1798,14 @@ static int igb_check_lbtest_frame(struct igb_rx_buffer *rx_buffer,
 
 	frame_size >>= 1;
 
-	data = kmap(rx_buffer->page);
+	data = kmap_local_page(rx_buffer->page);
 
 	if (data[3] != 0xFF ||
 	    data[frame_size + 10] != 0xBE ||
 	    data[frame_size + 12] != 0xAF)
 		match = false;
 
-	kunmap(rx_buffer->page);
+	kunmap_local(data);
 
 	return match;
 }
-- 
2.35.2

Re: [PATCH v3] intel: igb: igb_ethtool.c: Convert kmap() to kmap_local_page()

Posted by Julia Lawall 4 years, 2 months ago


On Sat, 16 Apr 2022, Alaa Mohamed wrote:

> Convert kmap() to kmap_local_page()
>
> With kmap_local_page(), the mapping is per thread, CPU local and not
> globally visible.

It's not clearer.  This is a general statement about the function.  You
need to explain why it is appropriate to use it here.  Unless it is the
case that all calls to kmap should be converted to call kmap_local_page.

julia

>
> Signed-off-by: Alaa Mohamed <eng.alaamohamedsoliman.am@gmail.com>
> ---
> changes in V2:
> 	fix kunmap_local path value to take address of the mapped page.
> ---
> changes in V3:
> 	edit commit message to be clearer
> ---
>  drivers/net/ethernet/intel/igb/igb_ethtool.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> index 2a5782063f4c..c14fc871dd41 100644
> --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
> +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> @@ -1798,14 +1798,14 @@ static int igb_check_lbtest_frame(struct igb_rx_buffer *rx_buffer,
>
>  	frame_size >>= 1;
>
> -	data = kmap(rx_buffer->page);
> +	data = kmap_local_page(rx_buffer->page);
>
>  	if (data[3] != 0xFF ||
>  	    data[frame_size + 10] != 0xBE ||
>  	    data[frame_size + 12] != 0xAF)
>  		match = false;
>
> -	kunmap(rx_buffer->page);
> +	kunmap_local(data);
>
>  	return match;
>  }
> --
> 2.35.2
>
>
>

Re: [PATCH v3] intel: igb: igb_ethtool.c: Convert kmap() to kmap_local_page()

Posted by Alaa Mohamed 4 years, 2 months ago

On ١٦‏/٤‏/٢٠٢٢ ١٣:٣١, Julia Lawall wrote:
>
> On Sat, 16 Apr 2022, Alaa Mohamed wrote:
>
>> Convert kmap() to kmap_local_page()
>>
>> With kmap_local_page(), the mapping is per thread, CPU local and not
>> globally visible.
> It's not clearer.
I mean this " fix kunmap_local path value to take address of the mapped 
page" be more clearer
> This is a general statement about the function.  You
> need to explain why it is appropriate to use it here.  Unless it is the
> case that all calls to kmap should be converted to call kmap_local_page.
It's required to convert all calls kmap to kmap_local_page. So, I don't 
what should the commit message be?

Is this will be good :

"kmap_local_page() was recently developed as a replacement for kmap().  The
kmap_local_page() creates a mapping which is restricted to local use by a
single thread of execution. "
>
> julia
>
>> Signed-off-by: Alaa Mohamed <eng.alaamohamedsoliman.am@gmail.com>
>> ---
>> changes in V2:
>> 	fix kunmap_local path value to take address of the mapped page.
>> ---
>> changes in V3:
>> 	edit commit message to be clearer
>> ---
>>   drivers/net/ethernet/intel/igb/igb_ethtool.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c
>> index 2a5782063f4c..c14fc871dd41 100644
>> --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
>> +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
>> @@ -1798,14 +1798,14 @@ static int igb_check_lbtest_frame(struct igb_rx_buffer *rx_buffer,
>>
>>   	frame_size >>= 1;
>>
>> -	data = kmap(rx_buffer->page);
>> +	data = kmap_local_page(rx_buffer->page);
>>
>>   	if (data[3] != 0xFF ||
>>   	    data[frame_size + 10] != 0xBE ||
>>   	    data[frame_size + 12] != 0xAF)
>>   		match = false;
>>
>> -	kunmap(rx_buffer->page);
>> +	kunmap_local(data);
>>
>>   	return match;
>>   }
>> --
>> 2.35.2
>>
>>
>>

Re: [PATCH v3] intel: igb: igb_ethtool.c: Convert kmap() to kmap_local_page()

Posted by Julia Lawall 4 years, 2 months ago


On Sat, 16 Apr 2022, Alaa Mohamed wrote:

>
> On ١٦/٤/٢٠٢٢ ١٣:٣١, Julia Lawall wrote:
> >
> > On Sat, 16 Apr 2022, Alaa Mohamed wrote:
> >
> > > Convert kmap() to kmap_local_page()
> > >
> > > With kmap_local_page(), the mapping is per thread, CPU local and not
> > > globally visible.
> > It's not clearer.
> I mean this " fix kunmap_local path value to take address of the mapped page"
> be more clearer
> > This is a general statement about the function.  You
> > need to explain why it is appropriate to use it here.  Unless it is the
> > case that all calls to kmap should be converted to call kmap_local_page.
> It's required to convert all calls kmap to kmap_local_page. So, I don't what
> should the commit message be?

If all calls should be changed then you can also say that.

I thought that a previous commit on the outreachy list made some arguments
about how the affacted value was just allocated and thus could not yet be
shared.

julia

>
> Is this will be good :
>
> "kmap_local_page() was recently developed as a replacement for kmap().  The
> kmap_local_page() creates a mapping which is restricted to local use by a
> single thread of execution. "
> >
> > julia
> >
> > > Signed-off-by: Alaa Mohamed <eng.alaamohamedsoliman.am@gmail.com>
> > > ---
> > > changes in V2:
> > > 	fix kunmap_local path value to take address of the mapped page.
> > > ---
> > > changes in V3:
> > > 	edit commit message to be clearer
> > > ---
> > >   drivers/net/ethernet/intel/igb/igb_ethtool.c | 4 ++--
> > >   1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c
> > > b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> > > index 2a5782063f4c..c14fc871dd41 100644
> > > --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
> > > +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
> > > @@ -1798,14 +1798,14 @@ static int igb_check_lbtest_frame(struct
> > > igb_rx_buffer *rx_buffer,
> > >
> > >   	frame_size >>= 1;
> > >
> > > -	data = kmap(rx_buffer->page);
> > > +	data = kmap_local_page(rx_buffer->page);
> > >
> > >   	if (data[3] != 0xFF ||
> > >   	    data[frame_size + 10] != 0xBE ||
> > >   	    data[frame_size + 12] != 0xAF)
> > >   		match = false;
> > >
> > > -	kunmap(rx_buffer->page);
> > > +	kunmap_local(data);
> > >
> > >   	return match;
> > >   }
> > > --
> > > 2.35.2
> > >
> > >
> > >
>

Re: [PATCH v3] intel: igb: igb_ethtool.c: Convert kmap() to kmap_local_page()

Posted by Fabio M. De Francesco 4 years, 2 months ago

On sabato 16 aprile 2022 16:09:58 CEST Julia Lawall wrote:
> 
> On Sat, 16 Apr 2022, Alaa Mohamed wrote:
> 
> >
> > On Ù¡Ù¦/Ù¤/Ù¢Ù Ù¢Ù¢ Ù¡Ù£:Ù£Ù¡, Julia Lawall wrote:
> > >
> > > On Sat, 16 Apr 2022, Alaa Mohamed wrote:
> > >
> > > > Convert kmap() to kmap_local_page()
> > > >
> > > > With kmap_local_page(), the mapping is per thread, CPU local and 
not
> > > > globally visible.
> > > It's not clearer.
> > I mean this " fix kunmap_local path value to take address of the mapped 
page"
> > be more clearer
> > > This is a general statement about the function.  You
> > > need to explain why it is appropriate to use it here.  Unless it is 
the
> > > case that all calls to kmap should be converted to call 
kmap_local_page.
> > It's required to convert all calls kmap to kmap_local_page. So, I don't 
what
> > should the commit message be?
> 
> If all calls should be changed then you can also say that.

If all calls should be changed with no regards to the surrounding contexts 
and special situations, we can just make an automated s/kmap()/
kmap_local_page()/ or something else similar :)

Thanks,

Fabio M. De Francesco

> 
> I thought that a previous commit on the outreachy list made some 
arguments
> about how the affacted value was just allocated and thus could not yet be
> shared.
> 
> julia