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Re: [PATCH][AArch64] Cleanup memset
On 26/02/20 21:41, Wilco Dijkstra wrote:
> Cleanup memset. Remove unnecessary code for unused ZVA sizes.
> For zero memsets it's faster use DC ZVA for >= 160 bytes rather
> than 256. Add a define which allows skipping the ZVA size test when
> the ZVA size is known to be 64 - reading dczid_el0 may be expensive.
> This simplifies the Falkor memset implementation.
This looks OK in general, although can you please elaborate on the
following:
- What cores did you test on to conclude that 160 is a better threshold
than 256?
- Is the intention to support non-64-byte zva sizes once there is actual
hardware that implements it and not bother with it for now? I agree
with the idea if that's the case, just that it would be nice to have
that documented in the git commit message.
Siddhesh