On 2/8/2022 6:42 PM, Stephen Hemminger wrote:
On Tue, 8 Feb 2022 18:00:27 +0000
Ferruh Yigit <ferruh.yi...@intel.com> wrote:
On 2/8/2022 5:45 PM, Stephen Hemminger wrote:
On Tue, 8 Feb 2022 13:48:00 +0000
Ciara Loftus <ciara.lof...@intel.com> wrote:
+- **Secondary Processes**
+
+ Rx and Tx are not supported for secondary processes due to the
single-producer
+ single-consumer nature of the AF_XDP rings. However other operations
including
+ statistics retrieval are permitted.
+ The maximum number of queues permitted for PMDs operating in this model is 8
+ as this is the maximum number of fds that can be sent through the IPC APIs as
+ defined by RTE_MP_MAX_FD_NUM.
+
This seems like a restriction that is true for most devices in DPDK.
Most other devices also have restriction that on queues;
the hardware descriptor ring can only be used by one thread at a time.
Is this different with AF_XDP?
I asked the same on v2 :) and Ciara explained the reason, it is on v2
discussion thread.
The wording of the message is what confused me.
It would be better to change:
due to the single-producer single-consumer nature of the AF_XDP rings
to
due to memory mapping of the AF_XDP rings being assigned by the kernel
in the primary process only.
+1
