Re: [PATCH RFC 2/6] perf dso: Refactor dso_cache__read()

[Jiri Olsa]

On Fri, Oct 25, 2019 at 03:59:56PM +0300, Adrian Hunter wrote:

SNIP

> +}
>  
> -	return ret;
> +static struct dso_cache *dso_cache__find(struct dso *dso,
> +					 struct machine *machine,
> +					 u64 offset,
> +					 ssize_t *ret)
> +{
> +	struct dso_cache *cache = __dso_cache__find(dso, offset);
> +
> +	return cache ? cache : dso_cache__populate(dso, machine, offset, ret);
>  }
>  
>  static ssize_t dso_cache_read(struct dso *dso, struct machine *machine,
>  			      u64 offset, u8 *data, ssize_t size)
>  {
>  	struct dso_cache *cache;
> +	ssize_t ret = 0;
>  
> -	cache = dso_cache__find(dso, offset);
> -	if (cache)
> -		return dso_cache__memcpy(cache, offset, data, size);
> -	else
> -		return dso_cache__read(dso, machine, offset, data, size);
> +	cache = dso_cache__find(dso, machine, offset, &ret);
> +	if (!cache)
> +		return ret;

why not use the ERR_* macros to get error through the pointer
instead of adding extra argument?

jirka


> +
> +	return dso_cache__memcpy(cache, offset, data, size);
>  }
>  
>  /*
> -- 
> 2.17.1
>