DMA Transfers to PCIe Bar Memory

[Stephen Hemminger]

On Thu, 7 Nov 2024 12:42:25 +0300
Dmitry Kozlyuk <dmitry.kozliuk at gmail.com> wrote:

> rte_memcpy() is intended for copy from RAM to RAM.
> You can Cc: Morten Brørup <mb at smartsharesystems.com> probably,
> but I doubt that rte_memcpy() is specialized for DMA in any way.
> The buffer may be filled with rte_mempcy() by application,
> but this is done before handling the buffer to PMD, and thus before DMA.

A little more detail.
rte_memcpy() was an attempt at optimization of memcpy().
With current compilers, rte_memcpy() and memcpy() end up producing close
to the same code; the only cases left where there is a difference is likely
because GCC is more pessemistic about alignment.
The plan is to get rid of rte_memcpy() all together.