In order to keep the current ability for the aim of debugging and avoid
printing the warning message twice, add ASSERT_BUG() macro definition to
harden the callers of division functions.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
---
 drivers/gpu/drm/amd/display/dc/os_types.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/os_types.h b/drivers/gpu/drm/amd/display/dc/os_types.h
index f2ba76c1e0c0..932bbe05ee0a 100644
--- a/drivers/gpu/drm/amd/display/dc/os_types.h
+++ b/drivers/gpu/drm/amd/display/dc/os_types.h
@@ -79,6 +79,11 @@
 			dc_breakpoint();	\
 	} while (0)
 
+#define ASSERT_BUG(expr) do {			\
+		dc_breakpoint();		\
+		BUG_ON(!(expr));		\
+	} while (0)
+
 #define BREAK_TO_DEBUGGER() \
 	do { \
 		DRM_DEBUG_DRIVER("%s():%d\n", __func__, __LINE__); \
-- 
2.42.0

Hi, Tiezhu,

On Tue, Jan 14, 2025 at 2:16 PM Tiezhu Yang <yangtiezhu@loongson.cn> wrote:
>
> In order to keep the current ability for the aim of debugging and avoid
> printing the warning message twice, add ASSERT_BUG() macro definition to
> harden the callers of division functions.
>
> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
> ---
>  drivers/gpu/drm/amd/display/dc/os_types.h | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/os_types.h b/drivers/gpu/drm/amd/display/dc/os_types.h
> index f2ba76c1e0c0..932bbe05ee0a 100644
> --- a/drivers/gpu/drm/amd/display/dc/os_types.h
> +++ b/drivers/gpu/drm/amd/display/dc/os_types.h
> @@ -79,6 +79,11 @@
>                         dc_breakpoint();        \
>         } while (0)
>
> +#define ASSERT_BUG(expr) do {                  \
> +               dc_breakpoint();                \
> +               BUG_ON(!(expr));                \
> +       } while (0)
I don't think this is correct, if KGDB is enabled, then whether expr
is true or false, ASSERT_BUG() will break to KGDB.

Huacai

> +
>  #define BREAK_TO_DEBUGGER() \
>         do { \
>                 DRM_DEBUG_DRIVER("%s():%d\n", __func__, __LINE__); \
> --
> 2.42.0
>
>

On 01/14/2025 04:29 PM, Huacai Chen wrote:
> Hi, Tiezhu,
>
> On Tue, Jan 14, 2025 at 2:16 PM Tiezhu Yang <yangtiezhu@loongson.cn> wrote:
>>
>> In order to keep the current ability for the aim of debugging and avoid
>> printing the warning message twice, add ASSERT_BUG() macro definition to
>> harden the callers of division functions.
>>
>> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
>> ---
>>  drivers/gpu/drm/amd/display/dc/os_types.h | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/display/dc/os_types.h b/drivers/gpu/drm/amd/display/dc/os_types.h
>> index f2ba76c1e0c0..932bbe05ee0a 100644
>> --- a/drivers/gpu/drm/amd/display/dc/os_types.h
>> +++ b/drivers/gpu/drm/amd/display/dc/os_types.h
>> @@ -79,6 +79,11 @@
>>                         dc_breakpoint();        \
>>         } while (0)
>>
>> +#define ASSERT_BUG(expr) do {                  \
>> +               dc_breakpoint();                \
>> +               BUG_ON(!(expr));                \
>> +       } while (0)
> I don't think this is correct, if KGDB is enabled, then whether expr
> is true or false, ASSERT_BUG() will break to KGDB.

It should check expr first, something like this:

#define ASSERT_BUG(expr) do {                   \
                 if (!(expr)) {                  \
                         dc_breakpoint();        \
                         BUG();                  \
                 }                               \
         } while (0)

I will send v4 later.

Thanks,
Tiezhu