Re: [PATCH v6 1/2] crypto: introduce: acomp_is_async to expose if comp drivers might sleep

[Chris Li]

On Thu, Feb 22, 2024 at 12:12 AM Barry Song <21cnbao@xxxxxxxxx> wrote:
>
> From: Barry Song <v-songbaohua@xxxxxxxx>
>
> acomp's users might want to know if acomp is really async to
> optimize themselves. One typical user which can benefit from
> exposed async stat is zswap.
>
> In zswap, zsmalloc is the most commonly used allocator for
> (and perhaps the only one). For zsmalloc, we cannot sleep
> while we map the compressed memory, so we copy it to a
> temporary buffer. By knowing the alg won't sleep can help
> zswap to avoid the need for a buffer. This shows noticeable
> improvement in load/store latency of zswap.
>
> Signed-off-by: Barry Song <v-songbaohua@xxxxxxxx>
> Acked-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>

Acked-by: Chris Li <chrisl@xxxxxxxxxx>

Chris

> ---
>  include/crypto/acompress.h | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/include/crypto/acompress.h b/include/crypto/acompress.h
> index 574cffc90730..80e243611fe2 100644
> --- a/include/crypto/acompress.h
> +++ b/include/crypto/acompress.h
> @@ -160,6 +160,12 @@ static inline void acomp_request_set_tfm(struct acomp_req *req,
>         req->base.tfm = crypto_acomp_tfm(tfm);
>  }
>
> +static inline bool acomp_is_async(struct crypto_acomp *tfm)
> +{
> +       return crypto_comp_alg_common(tfm)->base.cra_flags &
> +              CRYPTO_ALG_ASYNC;
> +}
> +
>  static inline struct crypto_acomp *crypto_acomp_reqtfm(struct acomp_req *req)
>  {
>         return __crypto_acomp_tfm(req->base.tfm);
> --
> 2.34.1
>