Hi All,
Considered that most people commented that eal option "--iova-mode" is a
better solution that gives user a chance not to use bus iova auto
detection scheme and want to override for some reason, I will generate
2nd version patch which will use eal option instead of compilation
configuration.
Eric
On 09/17/2018 04:32 AM, Stojaczyk, Dariusz wrote:
Hi,
A little bit of self-advertising:
I recently pushed patches that will make DPDK default to RTE_IOVA_VA when
physical addresses were not explicitly requested and are not available, e.g.
when running as a non-privileged user. It shouldn't cause any conflicts with
the changes you're proposing here, but any review is welcome.
pci/linux: use RTE_IOVA_VA whenever possible
http://patches.dpdk.org/patch/44392/
[v2] eal/bus: use RTE_IOVA_PA only if phys addresses are available
http://patches.dpdk.org/patch/44420/
As for the --iova-mode=<pa/va>, I agree it could help DPDK use cases where most
drivers or devices are hotplugged/hotattached at runtime - e.g. SPDK, it could
certainly make use of such param.
D.
-----Original Message-----
From: dev [mailto:dev-boun...@dpdk.org] On Behalf Of Eric Zhang
Sent: Tuesday, September 11, 2018 7:22 PM
To: Burakov, Anatoly <anatoly.bura...@intel.com>; Jerin Jacob
<jerin.ja...@caviumnetworks.com>
Cc: santosh <santosh.shu...@caviumnetworks.com>;
hemant.agra...@nxp.com; Gaëtan Rivet <gaetan.ri...@6wind.com>;
Richardson, Bruce <bruce.richard...@intel.com>; dev@dpdk.org;
allain.leg...@windriver.com; matt.pet...@windriver.com
Subject: Re: [dpdk-dev] [PATCH] eal: force IOVA mode to physical
On 09/07/2018 04:13 PM, Eric Zhang wrote:
On 09/07/2018 05:26 AM, Burakov, Anatoly wrote:
On 06-Sep-18 8:34 AM, Jerin Jacob wrote:
-----Original Message-----
Date: Tue, 4 Sep 2018 23:40:36 -0400
From: Eric Zhang <eric.zh...@windriver.com>
To: santosh <santosh.shu...@caviumnetworks.com>,
hemant.agra...@nxp.com,
Gaëtan Rivet <gaetan.ri...@6wind.com>, "Burakov, Anatoly"
<anatoly.bura...@intel.com>
CC: bruce.richard...@intel.com, dev@dpdk.org,
allain.leg...@windriver.com,
matt.pet...@windriver.com
Subject: Re: [dpdk-dev] [PATCH] eal: force IOVA mode to physical
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On 08/30/2018 08:59 AM, santosh wrote:
On Thursday 30 August 2018 05:43 PM, Hemant wrote:
External Email
Hi,
On 8/30/2018 3:13 PM, Gaëtan Rivet wrote:
Hi,
On Thu, Aug 30, 2018 at 10:09:04AM +0100, Burakov, Anatoly wrote:
On 29-Aug-18 4:58 PM, eric zhang wrote:
This patch adds a configuration option to force the IOVA mode
to physical address (PA). There exists virtual devices that
are not directly attached to the PCI bus, and therefore the
auto detection of the IOVA mode based on probing the PCI bus
and IOMMU configuration may not report the required
addressing
mode. Having the configuration option permits the mode to be
explicitly configured in this scenario.
Signed-off-by: eric zhang <eric.zh...@windriver.com>
---
Defining this at compile-time seems like an overkill. Wouldn't
it be better to just add an EAL command-line option to force
IOVA mode to a particular value?
That is a good suggestion.
--
Thanks,
Anatoly
What is the bus of these devices and why not implement
get_iommu_class in it?
There are cases, where you are using dpdk libraries with external
libraries and you need to change the default behavior DPDK lib to
use physical address instead of virtual address.
Providing an option to user will help.
More appropriate solution could be:
* Either fix it at bus layer .. i.e.. get_iommu_class()..
* Or introduce something like [1] --iova-mode=<pa/va> param.
Former is better solution than latter if autodetection is a key
criteria.
Thanks.
[1] http://patchwork.dpdk.org/patch/25192/
It's not generic which couldn't be fixed at bus layer.
So what's the preference of EAL option or compile time solution?
Adding --iova-mode as patch [1] will overrivde auto-detection
rte_bus_get_iommu_class()
make it no use; compile time solution will align with upstream and
keep new atuodetection solution in #ifndef.
If it is for vdev devices, why not introduce something like
RTE_PCI_DRV_IOVA_AS_VA and let vdev device describe its personality.
And based on the devices(flags) on vdev bus,
rte_bus_get_iommu_class() of vdev can decide the mode just like PCI
bus.
That seems like a better option to me, +1. As far as i know, at the
moment if there are no devices attached at all, or if there are only
vdev devices attached, DPDK will default to IOVA as PA mode for no
good reason; such a change would certainly fix this.
Thanks for the suggestions however our virtual device doesn't run dpdk
vdev code so we can't use the flag.
Notice that in eal.c there is one workaround that force iova to be PA
per virtual device is not directly attached to pci. That case is
checking kni module. Ours is a similar case that virtual device not
attach pci directly.
So we have to turn to force iova to PA either 1. compilation option 2.
eal option. Which one should be the preference by taking into
consideration that align with upstream?
Thanks
Any comments?
Thanks
Eric
