On (24/05/10 16:12), Herbert Xu wrote:
> On Fri, May 10, 2024 at 05:08:27PM +0900, Sergey Senozhatsky wrote:
> >
> > For some algorithms params needs to be set before ctx is created.
> > For example zstd, crypto/zstd calls zstd_get_params(ZSTD_DEF_LEVEL, 0)
> > to estimate workspace size, which misses the opportunity to configure
> > it an way zram/zswap can benefit from, because those work with PAGE_SIZE
> > source buffer. So for zram zstd_get_params(ZSTD_DEF_LEVEL, PAGE_SIZE)
> > is much better (it saves 1.2MB per ctx, which is per-CPU in zram). Not
> > to mention that zstd_get_params(param->level, 0) is what we need at the
> > end.
>
> For these algorithms where the overhead of allocating a default
> set of parameters and then changing them on a setparam call is
> too high, we could stipulate that the tfm can only be used after
> a setparam call (just as we require a setkey before cipher ops).
OK. I guess for drivers' params support (dictionaries handling etc.)
we take take some code from this series. You mentioned acomp, does this
mean setparam is for async compression only?