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[PATCH] drm/i915: make a handful of read-only arrays static const

Colin Ian King posted 1 patch 4 years, 4 months ago
There is a newer version of this series
drivers/gpu/drm/i915/display/intel_vdsc.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
[PATCH] drm/i915: make a handful of read-only arrays static const
Posted by Colin Ian King 4 years, 4 months ago 
Don't populate the read-only arrays on the stack but instead make
them static const. Also makes the object code a little smaller.
Reformat the statements to clear up checkpatch warning.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
---
 drivers/gpu/drm/i915/display/intel_vdsc.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
index 3faea903b9ae..d49f66237ec3 100644
--- a/drivers/gpu/drm/i915/display/intel_vdsc.c
+++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
@@ -378,10 +378,18 @@ calculate_rc_params(struct rc_parameters *rc,
 {
 	int bpc = vdsc_cfg->bits_per_component;
 	int bpp = vdsc_cfg->bits_per_pixel >> 4;
-	int ofs_und6[] = { 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 };
-	int ofs_und8[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
-	int ofs_und12[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
-	int ofs_und15[] = { 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12 };
+	static const int ofs_und6[] = {
+		0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
+	};
+	static const int ofs_und8[] = {
+		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
+	};
+	static const int ofs_und12[] = {
+		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
+	};
+	static const int ofs_und15[] = {
+		10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12
+	};
 	int qp_bpc_modifier = (bpc - 8) * 2;
 	u32 res, buf_i, bpp_i;
 
-- 
2.34.1
Re: [PATCH] drm/i915: make a handful of read-only arrays static const
Posted by Jani Nikula 4 years, 4 months ago 
On Tue, 22 Feb 2022, Colin Ian King <colin.i.king@gmail.com> wrote:
> Don't populate the read-only arrays on the stack but instead make
> them static const. Also makes the object code a little smaller.
> Reformat the statements to clear up checkpatch warning.
>
> Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
> ---
>  drivers/gpu/drm/i915/display/intel_vdsc.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 3faea903b9ae..d49f66237ec3 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -378,10 +378,18 @@ calculate_rc_params(struct rc_parameters *rc,
>  {
>  	int bpc = vdsc_cfg->bits_per_component;
>  	int bpp = vdsc_cfg->bits_per_pixel >> 4;
> -	int ofs_und6[] = { 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 };
> -	int ofs_und8[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> -	int ofs_und12[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> -	int ofs_und15[] = { 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12 };
> +	static const int ofs_und6[] = {
> +		0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
> +	};
> +	static const int ofs_und8[] = {
> +		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> +	};
> +	static const int ofs_und12[] = {
> +		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> +	};

Hmm, I wonder why the same values are duplicated in ofs_und8 and
ofs_und12. Cc: Vandita, Manasi.

Regardless, the patch is sane.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>

> +	static const int ofs_und15[] = {
> +		10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12
> +	};
>  	int qp_bpc_modifier = (bpc - 8) * 2;
>  	u32 res, buf_i, bpp_i;

-- 
Jani Nikula, Intel Open Source Graphics Center
Re: [Intel-gfx] [PATCH] drm/i915: make a handful of read-only arrays static const
Posted by Ville Syrjälä 4 years, 4 months ago 
On Tue, Feb 22, 2022 at 12:03:23PM +0000, Colin Ian King wrote:
> Don't populate the read-only arrays on the stack but instead make
> them static const. Also makes the object code a little smaller.
> Reformat the statements to clear up checkpatch warning.
> 
> Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
> ---
>  drivers/gpu/drm/i915/display/intel_vdsc.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 3faea903b9ae..d49f66237ec3 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -378,10 +378,18 @@ calculate_rc_params(struct rc_parameters *rc,
>  {
>  	int bpc = vdsc_cfg->bits_per_component;
>  	int bpp = vdsc_cfg->bits_per_pixel >> 4;
> -	int ofs_und6[] = { 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 };
> -	int ofs_und8[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> -	int ofs_und12[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> -	int ofs_und15[] = { 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12 };
> +	static const int ofs_und6[] = {
> +		0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
> +	};
> +	static const int ofs_und8[] = {
> +		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> +	};
> +	static const int ofs_und12[] = {
> +		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> +	};
> +	static const int ofs_und15[] = {
> +		10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12
> +	};

Please shrink to s8 while at it.

>  	int qp_bpc_modifier = (bpc - 8) * 2;
>  	u32 res, buf_i, bpp_i;
>  
> -- 
> 2.34.1

-- 
Ville Syrjälä
Intel

Patchew 2.1-devel-ea86937

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