linux-kernel - Re: [PATCH v4 6/7] media: venus: helpers: update NUM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 2 Oct 2021 00:31:08 +0300
From:   Stanimir Varbanov <stanimir.varbanov@...aro.org>
To:     Dikshita Agarwal <dikshita@...eaurora.org>,
        linux-media@...r.kernel.org, stanimir.varbanov@...aro.org
Cc:     linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        vgarodia@...eaurora.org
Subject: Re: [PATCH v4 6/7] media: venus: helpers: update NUM_MBS macro
 calculation

Hi,

On 8/10/21 12:47 PM, Dikshita Agarwal wrote:
> Consider alignment while calculating NUM_MBS.
> 
> Co-developed-by: Mansur Alisha Shaik <mansur@...eaurora.org>
> Signed-off-by: Dikshita Agarwal <dikshita@...eaurora.org>
> ---
>  drivers/media/platform/qcom/venus/helpers.c | 13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/media/platform/qcom/venus/helpers.c b/drivers/media/platform/qcom/venus/helpers.c
> index 60a2775..2db33ba 100644
> --- a/drivers/media/platform/qcom/venus/helpers.c
> +++ b/drivers/media/platform/qcom/venus/helpers.c
> @@ -18,8 +18,8 @@
>  #include "hfi_platform.h"
>  #include "hfi_parser.h"
>  
> -#define NUM_MBS_720P	(((1280 + 15) >> 4) * ((720 + 15) >> 4))
> -#define NUM_MBS_4K	(((4096 + 15) >> 4) * ((2304 + 15) >> 4))
> +#define NUM_MBS_720P	(((ALIGN(1280, 16)) >> 4) * ((ALIGN(736, 16)) >> 4))
> +#define NUM_MBS_4K	(((ALIGN(4096, 16)) >> 4) * ((ALIGN(2304, 16)) >> 4))
>  
>  struct intbuf {
>  	struct list_head list;
> @@ -1098,16 +1098,17 @@ static u32 venus_helper_get_work_mode(struct venus_inst *inst)
>  	u32 num_mbs;
>  
>  	mode = VIDC_WORK_MODE_2;
> +
>  	if (inst->session_type == VIDC_SESSION_TYPE_DEC) {
> -		num_mbs = (ALIGN(inst->height, 16) * ALIGN(inst->width, 16)) / 256;
> +		num_mbs = ((ALIGN(inst->height, 16))/16 * (ALIGN(inst->width, 16)))/16;

Could you help me understand what is the difference between both
calculations? IMO this patch should only change NUM_MBS_720P and
NUM_MBS_4K macros.

>  		if (inst->hfi_codec == HFI_VIDEO_CODEC_MPEG2 ||
> -		    inst->pic_struct != HFI_INTERLACE_FRAME_PROGRESSIVE ||
> -		    num_mbs <= NUM_MBS_720P)
> +			inst->pic_struct != HFI_INTERLACE_FRAME_PROGRESSIVE ||
> +			num_mbs <= NUM_MBS_720P)

This change just makes indentation wrong and also it is not related to
the patch subject.

>  			mode = VIDC_WORK_MODE_1;
>  	} else {
>  		num_mbs = (ALIGN(inst->out_height, 16) * ALIGN(inst->out_width, 16)) / 256;
>  		if (inst->hfi_codec == HFI_VIDEO_CODEC_VP8 &&
> -		    num_mbs <= NUM_MBS_4K)
> +			num_mbs <= NUM_MBS_4K)

ditto

>  			mode = VIDC_WORK_MODE_1;
>  	}
>  
> 

-- 
regards,
Stan