Re: [PATCH v2 2/6] accel: accel_available() function

[Claudio Fontana <cfontana@suse.de>]

On 11/26/20 3:25 PM, Paolo Bonzini wrote:
> On 26/11/20 15:13, Claudio Fontana wrote:
>> One option I see is simply to document the behavior where
>> accel_available() is declared in accel.h (ie do not use in fast
>> path), as well as in accel_find() actually, so that both accel_find()
>> and accel_available() are avoided in fast path and avoid being called
>> frequently at runtime.
>>
>> Another option could be to remove the allocation completely, and use
>> for example accel_find(ACCEL_CLASS_NAME("tcg")), or another option
>> again would be to remove the allocation and use either a fixed buffer
>> + snprintf, or alloca -like builtin code to use the stack, ...
>>
>> Not a big deal, but with a general utility and short name like
>> accel_available(name) it might be tempting to use this more in the
>> future?
> 
> I think it's just that the usecase is not that common.  "Is this 
> accelerator compiled in the binary" is not something you need after 
> startup (or if querying the monitor).
> 
> Paolo
> 
> 

A script that repeatedly uses the QMP interface to query for the status could generate fragmentation this way I think.

Ciao,

Claudio