RE: [PATCH v2 08/19] crypto: x86/ghash - limit FPU preemption

[Elliott, Robert (Servers)]

> > +	while (srclen >= GHASH_BLOCK_SIZE) {
> > +		unsigned int fpulen = min(srclen, FPU_BYTES);
> > +
> > +		kernel_fpu_begin();
> > +		while (fpulen >= GHASH_BLOCK_SIZE) {
> > +			int n = min_t(unsigned int, fpulen, GHASH_BLOCK_SIZE);
> > +
> > +			clmul_ghash_update(dst, src, n, &ctx->shash);
> > +
> > +			srclen -= n;
> > +			fpulen -= n;
> > +			src += n;
> > +		}
> > +		kernel_fpu_end();
> > +	}
> 
> Another loop that doesn't make sense.  Why is this only passing 16 bytes at a
> time into the assembly code?  There shouldn't be an inner loop here at all.

Thanks, copied the pattern from another function whose assembly function
had a size limit. clmul_ghash_update looks ready for all sizes, so I'll
simplify that.