Hi Gaetan
Thanks for the review.
Some comments..
> -----Original Message-----
> From: Gaëtan Rivet [mailto:gaetan.ri...@6wind.com]
> Sent: Wednesday, December 13, 2017 5:17 PM
> To: Matan Azrad <ma...@mellanox.com>
> Cc: Adrien Mazarguil <adrien.mazarg...@6wind.com>; Thomas Monjalon
> <tho...@monjalon.net>; dev@dpdk.org; sta...@dpdk.org
> Subject: Re: [PATCH v2 4/4] net/failsafe: fix removed device handling
>
> Hi Matan,
>
> On Wed, Dec 13, 2017 at 02:29:30PM +0000, Matan Azrad wrote:
> > There is time between the physical removal of the device until
> > sub-device PMDs get a RMV interrupt. At this time DPDK PMDs and
> > applications still don't know about the removal and may call
> > sub-device control operation which should return an error.
> >
> > In previous code this error is reported to the application contrary to
> > fail-safe principle that the app should not be aware of device removal.
> >
> > Add an removal check in each relevant control command error flow and
> > prevent an error report to application when the sub-device is removed.
> >
> > Fixes: a46f8d5 ("net/failsafe: add fail-safe PMD")
> > Fixes: b737a1e ("net/failsafe: support flow API")
> > Cc: sta...@dpdk.org
> >
>
> This patch is not a fix.
> It relies on an eth_dev API evolution. Without this evolution, this patch is
> meaningless and would break compilation if backported in stable branch.
>
It is a fix because the bug is finally solved by this patch.
I agree that it cannot be backported itself, but maybe all the series should be
backported.
Other idea:
Add new patch which documents the bug and backport it.
Remove it in this patch and remove cc stable from it.
What do you think?
> Please remove those tags.
>
> > Signed-off-by: Matan Azrad <ma...@mellanox.com>
> > ---
> > drivers/net/failsafe/failsafe_flow.c | 18 ++++++++++-------
> > drivers/net/failsafe/failsafe_ops.c | 34 ++++++++++++++++++++++-----
> ------
> > drivers/net/failsafe/failsafe_private.h | 10 ++++++++++
> > 3 files changed, 44 insertions(+), 18 deletions(-)
>
> < ... >
>
> > +/*
> > + * Check if sub device was removed.
> > + */
> > +static inline int
> > +fs_is_removed(struct sub_device *sdev) {
> > + if (sdev->remove == 1 || rte_eth_dev_is_removed(PORT_ID(sdev))
> != 0)
> > + return 1;
> > + return 0;
> > +}
>
> Have you considered adding this check within the subdev iterator itself?
> I think it would prevent you from having to add it to each return value
> checks.
>
> It is still MT-unsafe anyway.
>
This fix doesn't come to solve the MT issue, It comes to solve the error report
to application because of removal.
Adding the check in subdev iterator doesn't make sense for this issue.
Matan.
> --
> Gaëtan Rivet
> 6WIND
