Re: [PATCH 3/7] eal: move virtual device probing into a bus

-----Original Message-----
From: Wiles, Keith [mailto:keith.wiles@intel.com]
Sent: Wednesday, February 15, 2017 7:53 PM
To: Shreyansh Jain <redacted>
Cc: Jan Blunck <redacted>; dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH 3/7] eal: move virtual device probing into a
bus

quoted

On Feb 15, 2017, at 8:15 AM, Shreyansh Jain [off-list ref] wrote:

On Wednesday 15 February 2017 07:41 PM, Shreyansh Jain wrote:

quoted

On Wednesday 15 February 2017 03:32 PM, Jan Blunck wrote:

quoted

This is a refactoring of the virtual device probing which moves into into
a proper bus structure.

Signed-off-by: Jan Blunck <redacted>
---
lib/librte_eal/common/eal_common_dev.c  | 22 -----------------
lib/librte_eal/common/eal_common_vdev.c | 44
+++++++++++++++++++++++++++++++++
2 files changed, 44 insertions(+), 22 deletions(-)

[...]

quoted

diff --git a/lib/librte_eal/common/eal_common_vdev.c

b/lib/librte_eal/common/eal_common_vdev.c
index 7d6e54f..523a3d6 100644

--- a/lib/librte_eal/common/eal_common_vdev.c
+++ b/lib/librte_eal/common/eal_common_vdev.c

@@ -37,8 +37,10 @@

#include <stdint.h>
#include <sys/queue.h>

[...]

quoted

+
+static struct rte_bus rte_vdev_bus = {
+    .scan = vdev_scan,
+    .probe = vdev_probe,
+};
+
+RTE_REGISTER_BUS_LATE(virtual, rte_vdev_bus);

Does it matter if VDEV buses are registered before or after other
buses? Either way, the callbacks would be called in the order specified
in EAL.

Just ignore this comment - I am misunderstood something.

But another question: Is there specific reason VDEV should be

registered/scanned *after* other devices? Is there some specific problem if
we do otherwise? (I think this is should be done, but I don't have a specific
reason).

Does the bonding driver which uses physical devices need to be registered
after physical ones? In Pktgen I noticed the vdev after the physical ports
and I could not blacklist them as the bonding driver needed them, which
caused the bonding ports to have a greater port number. In the case of pktgen
the bonding ports were up around 8 or 10 and caused the display to not show
the bonding ports. This is really just a usability problem for the developer
using Pktgen. I would like to see the vdev devices first, but as long as the
drivers (like bonding) are fine with them being first.

Ah, now I remember - there was a patch from Jerin for this.
Probably he is the best person to comment here.
(I don't have much insight here). 

Regards,
Keith