From: Stephen Hemminger <stephen@networkplumber.org>
To: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
Cc: "Wieckowski, Jacob" <Jacob.Wieckowski@vector.com>,
"users@dpdk.org" <users@dpdk.org>
Subject: Re: DMA Transfers to PCIe Bar Memory
Date: Thu, 7 Nov 2024 08:11:16 -0800 [thread overview]
Message-ID: <20241107081116.0d777dd1@hermes.local> (raw)
In-Reply-To: <20241107124225.50c22ee2@sovereign>
On Thu, 7 Nov 2024 12:42:25 +0300
Dmitry Kozlyuk <dmitry.kozliuk@gmail.com> wrote:
> rte_memcpy() is intended for copy from RAM to RAM.
> You can Cc: Morten Brørup <mb@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.
prev parent reply other threads:[~2024-11-07 16:11 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-11-06 15:50 Wieckowski, Jacob
2024-11-06 17:46 ` Dmitry Kozlyuk
2024-11-07 9:16 ` Wieckowski, Jacob
2024-11-07 9:42 ` Dmitry Kozlyuk
2024-11-07 13:09 ` Wieckowski, Jacob
2024-11-07 16:13 ` Stephen Hemminger
2024-11-07 16:11 ` Stephen Hemminger [this message]
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