From: Thomas Monjalon <thomas@monjalon.net>
To: Ferruh Yigit <ferruh.yigit@xilinx.com>,
"Min Hu (Connor)" <humin29@huawei.com>,
Ferruh Yigit <ferruh.yigit@intel.com>,
Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>,
David Marchand <david.marchand@redhat.com>,
"lihuisong (C)" <lihuisong@huawei.com>
Cc: dev <dev@dpdk.org>, dpdk stable <stable@dpdk.org>,
Bruce Richardson <bruce.richardson@intel.com>
Subject: Re: [PATCH] ethdev: fix push new event
Date: Fri, 03 Jun 2022 09:42:18 +0200 [thread overview]
Message-ID: <2511545.Lt9SDvczpP@thomas> (raw)
In-Reply-To: <f70201a8-8560-5654-b680-abdedc69a730@huawei.com>
02/06/2022 13:24, lihuisong (C):
>
> 在 2022/5/30 19:10, Ferruh Yigit 写道:
> > On 5/30/2022 9:28 AM, Thomas Monjalon wrote:
> >> [CAUTION: External Email]
> >>
> >> 28/05/2022 10:53, lihuisong (C):
> >>>
> >>> 在 2022/5/23 22:36, Thomas Monjalon 写道:
> >>>> 23/05/2022 11:51, David Marchand:
> >>>>> On Sat, May 21, 2022 at 8:57 AM Min Hu
> >>>>> (Connor)<humin29@huawei.com> wrote:
> >>>>>> From: Huisong Li<lihuisong@huawei.com>
> >>>>>>
> >>>>>> The 'state' in struct rte_eth_dev may be used to update some
> >>>>>> information
> >>>>>> when app receive these events. For example, when app receives a
> >>>>>> new event,
> >>>>>> app may get the socket id of this port by calling
> >>>>>> rte_eth_dev_socket_id to
> >>>>>> setup the attached port. The 'state' is used in
> >>>>>> rte_eth_dev_socket_id.
> >>>>>>
> >>>>>> If the state isn't modified to RTE_ETH_DEV_ATTACHED before
> >>>>>> pushing the new
> >>>>>> event, app will get the socket id failed. So this patch moves
> >>>>>> pushing event
> >>>>>> operation after the state updated.
> >>>>>>
> >>>>>> Fixes: 99a2dd955fba ("lib: remove librte_ prefix from directory
> >>>>>> names")
> >>>>> A patch moving code is unlikely to be at fault.
> >>>>>
> >>>>>
> >>>>> Looking at the patch which moved those notifications in this point of
> >>>>> the code, the state update was pushed after the notification on
> >>>>> purpose.
> >>>>> See be8cd210379a ("ethdev: fix port probing notification")
> >>>>>
> >>>>> ethdev: fix port probing notification
> >>>>>
> >>>>> The new device was notified as soon as it was allocated.
> >>>>> It leads to use a device which is not yet initialized.
> >>>>>
> >>>>> The notification must be published after the initialization
> >>>>> is done
> >>>>> by the PMD, but before the state is changed, in order to let
> >>>>> notified entities taking ownership before general availability.
> >>>>>
> >>>>>
> >>>>> Do we need an intermediate state during probing?
> >>>> Possibly. Currently we have only 3 states:
> >>>> RTE_ETH_DEV_UNUSED
> >>>> RTE_ETH_DEV_ATTACHED
> >>>> RTE_ETH_DEV_REMOVED
> >>>>
> >>>> We may add RTE_ETH_DEV_ALLOCATED just before calling
> >>>> rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_NEW, NULL);
> >>>> Then we would need to check against RTE_ETH_DEV_ALLOCATED
> >>>> in some ethdev functions.
> >>>>
> >>> Hi, Thomas,
> >>>
> >>> Do you mean that we need to modify some funcions like following?
> >>>
> >>> int rte_eth_dev_is_valid_port(uint16_t port_id)
> >>> {
> >>> if (port_id >= RTE_MAX_ETHPORTS ||
> >>> (rte_eth_devices[port_id].state != *RTE_ETH_DEV_ALLOCATED*))
> >>> return 0;
> >
> > Won't this mark ATTACHED devices as invalid?
> Yes, You are right.
>
> > If the state flow will be as UNUSED -> ALLOCATED -> ATTACHED, above
> > check should be against 'ATTACHED' I think.
It should validate both ALLOCATED and ATTACHED.
> If these check is against 'ATTACHED', it goes back to the issue this
> patch mentioned.
>
> The failsafe PMD applications expect sending event before device state
> set to 'ATTACHED'.
> But other applications expect the device with 'ATTACHED' state before
> send event.
> They are in conflict with each other. So we can't solve this issue by
> adding an
> 'RTE_ETH_DEV_ALLOCATED' state.
next prev parent reply other threads:[~2022-06-03 7:42 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-21 6:55 Min Hu (Connor)
2022-05-23 9:51 ` David Marchand
2022-05-23 12:33 ` Ferruh Yigit
2022-05-23 14:36 ` Thomas Monjalon
2022-05-28 8:53 ` lihuisong (C)
2022-05-30 8:28 ` Thomas Monjalon
2022-05-30 11:10 ` Ferruh Yigit
2022-06-02 11:24 ` lihuisong (C)
2022-06-03 7:42 ` Thomas Monjalon [this message]
2022-06-07 1:23 ` lihuisong (C)
2022-06-07 6:44 ` Thomas Monjalon
2022-06-11 8:59 ` lihuisong (C)
2022-09-27 10:29 ` Thomas Monjalon
2022-10-08 4:06 ` lihuisong (C)
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