LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
* [PATCH] arm64: mm: make CONFIG_ZONE_DMA32 configurable
@ 2019-05-27 16:08 Miles Chen
  2019-05-28 10:43 ` Robin Murphy
  0 siblings, 1 reply; 3+ messages in thread
From: Miles Chen @ 2019-05-27 16:08 UTC (permalink / raw)
  To: Catalin Marinas, Will Deacon
  Cc: linux-arm-kernel, linux-kernel, linux-mediatek, wsd_upstream, Miles Chen

This change makes CONFIG_ZONE_DMA32 defuly y and allows users
to overwrite it.

For the SoCs that do not need CONFIG_ZONE_DMA32, this is the
first step to manage all available memory by a single
zone(normal zone) to reduce the overhead of multiple zones.

The change also fixes a build error when CONFIG_NUMA=y and
CONFIG_ZONE_DMA32=n.

arch/arm64/mm/init.c:195:17: error: use of undeclared identifier 'ZONE_DMA32'
                max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());

Signed-off-by: Miles Chen <miles.chen@mediatek.com>
---
 arch/arm64/Kconfig   | 3 ++-
 arch/arm64/mm/init.c | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 76f6e4765f49..9d20a736d1d1 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -260,7 +260,8 @@ config GENERIC_CALIBRATE_DELAY
 	def_bool y
 
 config ZONE_DMA32
-	def_bool y
+	bool "Support DMA32 zone"
+	default y
 
 config HAVE_GENERIC_GUP
 	def_bool y
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index d2adffb81b5d..96829ce21f99 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -191,8 +191,10 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 {
 	unsigned long max_zone_pfns[MAX_NR_ZONES]  = {0};
 
+#ifdef CONFIG_ZONE_DMA32
 	if (IS_ENABLED(CONFIG_ZONE_DMA32))
 		max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());
+#endif
 	max_zone_pfns[ZONE_NORMAL] = max;
 
 	free_area_init_nodes(max_zone_pfns);
-- 
2.18.0


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] arm64: mm: make CONFIG_ZONE_DMA32 configurable
  2019-05-27 16:08 [PATCH] arm64: mm: make CONFIG_ZONE_DMA32 configurable Miles Chen
@ 2019-05-28 10:43 ` Robin Murphy
  2019-05-28 15:46   ` Miles Chen
  0 siblings, 1 reply; 3+ messages in thread
From: Robin Murphy @ 2019-05-28 10:43 UTC (permalink / raw)
  To: Miles Chen, Catalin Marinas, Will Deacon
  Cc: linux-mediatek, linux-kernel, linux-arm-kernel, wsd_upstream

On 27/05/2019 17:08, Miles Chen wrote:
> This change makes CONFIG_ZONE_DMA32 defuly y and allows users
> to overwrite it.
> 
> For the SoCs that do not need CONFIG_ZONE_DMA32, this is the
> first step to manage all available memory by a single
> zone(normal zone) to reduce the overhead of multiple zones.
> 
> The change also fixes a build error when CONFIG_NUMA=y and
> CONFIG_ZONE_DMA32=n.
> 
> arch/arm64/mm/init.c:195:17: error: use of undeclared identifier 'ZONE_DMA32'
>                  max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());
> 
> Signed-off-by: Miles Chen <miles.chen@mediatek.com>
> ---
>   arch/arm64/Kconfig   | 3 ++-
>   arch/arm64/mm/init.c | 2 ++
>   2 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 76f6e4765f49..9d20a736d1d1 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -260,7 +260,8 @@ config GENERIC_CALIBRATE_DELAY
>   	def_bool y
>   
>   config ZONE_DMA32
> -	def_bool y
> +	bool "Support DMA32 zone"

This probably warrants an "if EMBEDDED" or "if EXPERT", since turning it 
off produces a kernel which won't work at all on certain systems (I've 
played around with this before...)

> +	default y
>   
>   config HAVE_GENERIC_GUP
>   	def_bool y
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index d2adffb81b5d..96829ce21f99 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -191,8 +191,10 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
>   {
>   	unsigned long max_zone_pfns[MAX_NR_ZONES]  = {0};
>   
> +#ifdef CONFIG_ZONE_DMA32
>   	if (IS_ENABLED(CONFIG_ZONE_DMA32))

There's no point keeping the IS_ENABLED() check when it's entirely 
redundant with the #ifdefs.

Robin.

>   		max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());
> +#endif
>   	max_zone_pfns[ZONE_NORMAL] = max;
>   
>   	free_area_init_nodes(max_zone_pfns);
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] arm64: mm: make CONFIG_ZONE_DMA32 configurable
  2019-05-28 10:43 ` Robin Murphy
@ 2019-05-28 15:46   ` Miles Chen
  0 siblings, 0 replies; 3+ messages in thread
From: Miles Chen @ 2019-05-28 15:46 UTC (permalink / raw)
  To: Robin Murphy
  Cc: Catalin Marinas, Will Deacon, linux-mediatek, linux-kernel,
	linux-arm-kernel, wsd_upstream

On Tue, 2019-05-28 at 11:43 +0100, Robin Murphy wrote:
> On 27/05/2019 17:08, Miles Chen wrote:
> > This change makes CONFIG_ZONE_DMA32 defuly y and allows users
> > to overwrite it.
> > 
> > For the SoCs that do not need CONFIG_ZONE_DMA32, this is the
> > first step to manage all available memory by a single
> > zone(normal zone) to reduce the overhead of multiple zones.
> > 
> > The change also fixes a build error when CONFIG_NUMA=y and
> > CONFIG_ZONE_DMA32=n.
> > 
> > arch/arm64/mm/init.c:195:17: error: use of undeclared identifier 'ZONE_DMA32'
> >                  max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());
> > 
> > Signed-off-by: Miles Chen <miles.chen@mediatek.com>
> > ---
> >   arch/arm64/Kconfig   | 3 ++-
> >   arch/arm64/mm/init.c | 2 ++
> >   2 files changed, 4 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > index 76f6e4765f49..9d20a736d1d1 100644
> > --- a/arch/arm64/Kconfig
> > +++ b/arch/arm64/Kconfig
> > @@ -260,7 +260,8 @@ config GENERIC_CALIBRATE_DELAY
> >   	def_bool y
> >   
> >   config ZONE_DMA32
> > -	def_bool y
> > +	bool "Support DMA32 zone"
> 
> This probably warrants an "if EMBEDDED" or "if EXPERT", since turning it 
> off produces a kernel which won't work at all on certain systems (I've 
> played around with this before...)

Thanks for your comment. 
I'll put a "if EXPERT"  here to avoid this case.

> 
> > +	default y
> >   
> >   config HAVE_GENERIC_GUP
> >   	def_bool y
> > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> > index d2adffb81b5d..96829ce21f99 100644
> > --- a/arch/arm64/mm/init.c
> > +++ b/arch/arm64/mm/init.c
> > @@ -191,8 +191,10 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
> >   {
> >   	unsigned long max_zone_pfns[MAX_NR_ZONES]  = {0};
> >   
> > +#ifdef CONFIG_ZONE_DMA32
> >   	if (IS_ENABLED(CONFIG_ZONE_DMA32))
> 
> There's no point keeping the IS_ENABLED() check when it's entirely 
> redundant with the #ifdefs.

I'll remove the IS_ENABLE() code in next patch.

-Miles
> 
> Robin.
> 
> >   		max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());
> > +#endif
> >   	max_zone_pfns[ZONE_NORMAL] = max;
> >   
> >   	free_area_init_nodes(max_zone_pfns);
> > 



^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2019-05-28 15:46 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-05-27 16:08 [PATCH] arm64: mm: make CONFIG_ZONE_DMA32 configurable Miles Chen
2019-05-28 10:43 ` Robin Murphy
2019-05-28 15:46   ` Miles Chen

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).