[PATCH v4 01/11] drm/xe: Simplify module initialization code

[Michal Wajdeczko]

On 7/29/2025 1:52 AM, John Harrison wrote:
> On 7/27/2025 10:19 AM, Michal Wajdeczko wrote:
>> There is no need to have extra checks and WARN() in the helpers
>> as instead of an index of the entry with function pointers, we
>> can pass pointer to the entry which we prepare directly in the
>> main loop, that is guaranteed to be valid.
> Not sure this counts as specific to configfs but it looks like a good clean up.

it becomes a prerequisite due to cleanup of xe_configfs_init()

> 
>>
>>    add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-180 (-180)
>>    Function                                     old     new   delta
>>    xe_exit                                      109      79     -30
>>    cleanup_module                               109      79     -30
>>    xe_init                                      248     188     -60
>>    init_module                                  248     188     -60
>>    Total: Before=2774145, After=2773965, chg -0.01%
>>
>> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>> Cc: Lucas De Marchi <lucas.demarchi at intel.com>
>> ---
>>   drivers/gpu/drm/xe/xe_module.c | 27 ++++++++++-----------------
>>   1 file changed, 10 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_module.c b/drivers/gpu/drm/xe/xe_module.c
>> index d9391bd08194..593bc9e5851a 100644
>> --- a/drivers/gpu/drm/xe/xe_module.c
>> +++ b/drivers/gpu/drm/xe/xe_module.c
>> @@ -135,24 +135,17 @@ static const struct init_funcs init_funcs[] = {
>>       },
>>   };
>>   -static int __init xe_call_init_func(unsigned int i)
>> +static int __init xe_call_init_func(const struct init_funcs *func)
>>   {
>> -    if (WARN_ON(i >= ARRAY_SIZE(init_funcs)))
>> -        return 0;
>> -    if (!init_funcs[i].init)
>> -        return 0;
>> -
>> -    return init_funcs[i].init();
>> +    if (func->init)
>> +        return func->init();
>> +    return 0;
>>   }
>>   -static void xe_call_exit_func(unsigned int i)
>> +static void xe_call_exit_func(const struct init_funcs *func)
>>   {
>> -    if (WARN_ON(i >= ARRAY_SIZE(init_funcs)))
>> -        return;
>> -    if (!init_funcs[i].exit)
>> -        return;
>> -
>> -    init_funcs[i].exit();
>> +    if (func->exit)
>> +        func->exit();
>>   }
>>     static int __init xe_init(void)
>> @@ -160,10 +153,10 @@ static int __init xe_init(void)
>>       int err, i;
>>         for (i = 0; i < ARRAY_SIZE(init_funcs); i++) {
>> -        err = xe_call_init_func(i);
>> +        err = xe_call_init_func(&init_funcs[i]);
> Would clearer to write as 'init_funcs + i'. The compiler should generate the same code but &x[i] is technically a reference to a derefence of an arithmetic operation rather than just an arithmetic operation.

ha, actually I had that this way, but decided to switch to
more frequently used &foo[i] pattern to avoid pushback ;)

but I can still make the other way (as now there are two of us)
> 
> Either way:
> Reviewed-by: John Harrison <John.C.Harrison at Intel.com>

thanks!

> 
>>           if (err) {
>>               while (i--)
>> -                xe_call_exit_func(i);
>> +                xe_call_exit_func(&init_funcs[i]);
>>               return err;
>>           }
>>       }
>> @@ -176,7 +169,7 @@ static void __exit xe_exit(void)
>>       int i;
>>         for (i = ARRAY_SIZE(init_funcs) - 1; i >= 0; i--)
>> -        xe_call_exit_func(i);
>> +        xe_call_exit_func(&init_funcs[i]);
>>   }
>>     module_init(xe_init);
>