RE: [PATCH][PATCH net-next] hv_netvsc: Add the support of hibernation

2019-09-12 Thread Dexuan Cui 
> From: Haiyang Zhang 
> Sent: Thursday, September 12, 2019 6:50 AM
> > -Original Message-
> > From: Dexuan Cui 
> > Sent: Wednesday, September 11, 2019 7:38 PM

> > +static int netvsc_suspend(struct hv_device *dev)
> > +{
> > +   struct net_device_context *ndev_ctx;
> > +   struct net_device *vf_netdev, *net;
> > +   struct netvsc_device *nvdev;
> > +   int ret;
> > +
> > +   net = hv_get_drvdata(dev);
> > +
> > +   ndev_ctx = netdev_priv(net);
> > +   cancel_delayed_work_sync(&ndev_ctx->dwork);
> > +
> > +   rtnl_lock();
> > +
> > +   nvdev = rtnl_dereference(ndev_ctx->nvdev);
> > +   if (nvdev == NULL) {
> > +   ret = -ENODEV;
> > +   goto out;
> > +   }
> > +
> > +   cancel_work_sync(&nvdev->subchan_work);
> 
> This looks redundant because netvsc_detach() cancels subchan_work.
> - Haiyang

You are right. I'll remove the superflous line 
cancel_work_sync(&nvdev->subchan_work);
in netvsc_suspend() in v2.

I'll wait for a few days before posting v2, in case people may have
other comments.

Thanks,
-- Dexuan

RE: [PATCH][PATCH net-next] hv_netvsc: Add the support of hibernation

2019-09-12 Thread Haiyang Zhang 



> -Original Message-
> From: Dexuan Cui 
> Sent: Wednesday, September 11, 2019 7:38 PM
> To: KY Srinivasan ; Haiyang Zhang
> ; Stephen Hemminger
> ; sas...@kernel.org; da...@davemloft.net;
> linux-hyp...@vger.kernel.org; net...@vger.kernel.org; linux-
> ker...@vger.kernel.org; Michael Kelley 
> Cc: Dexuan Cui 
> Subject: [PATCH][PATCH net-next] hv_netvsc: Add the support of hibernation
> 
> The existing netvsc_detach() and netvsc_attach() APIs make it easy to
> implement the suspend/resume callbacks.
> 
> Signed-off-by: Dexuan Cui 
> ---
> 
> This patch is basically a pure Hyper-V specific change and it has a
> build dependency on the commit 271b2224d42f ("Drivers: hv: vmbus:
> Implement
> suspend/resume for VSC drivers for hibernation"), which is on Sasha Levin's
> Hyper-V tree's hyperv-next branch:
> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit.k
> ernel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Fhyperv%2Flinux.git%2
> Flog%2F%3Fh%3Dhyperv-
> next&data=02%7C01%7Chaiyangz%40microsoft.com%7C0b84e40c446
> 648cc35fb08d737110e28%7C72f988bf86f141af91ab2d7cd011db47%7C1%7
> C0%7C637038418703112019&sdata=qd7DGFCJZ%2BDTix0VGcCe1JucV
> O97E0gILpVpcxlA6EE%3D&reserved=0
> 
> I request this patch should go through Sasha's tree rather than the
> net-next tree.
> 
>  drivers/net/hyperv/hyperv_net.h |  3 +++
>  drivers/net/hyperv/netvsc_drv.c | 59
> +
>  2 files changed, 62 insertions(+)
> 
> diff --git a/drivers/net/hyperv/hyperv_net.h
> b/drivers/net/hyperv/hyperv_net.h
> index ecc9af0..b8763ee 100644
> --- a/drivers/net/hyperv/hyperv_net.h
> +++ b/drivers/net/hyperv/hyperv_net.h
> @@ -952,6 +952,9 @@ struct net_device_context {
>   u32 vf_alloc;
>   /* Serial number of the VF to team with */
>   u32 vf_serial;
> +
> + /* Used to temporarily save the config info across hibernation */
> + struct netvsc_device_info *saved_netvsc_dev_info;
>  };
> 
>  /* Per channel data */
> diff --git a/drivers/net/hyperv/netvsc_drv.c
> b/drivers/net/hyperv/netvsc_drv.c
> index afdcc56..f920959 100644
> --- a/drivers/net/hyperv/netvsc_drv.c
> +++ b/drivers/net/hyperv/netvsc_drv.c
> @@ -2392,6 +2392,63 @@ static int netvsc_remove(struct hv_device *dev)
>   return 0;
>  }
> 
> +static int netvsc_suspend(struct hv_device *dev)
> +{
> + struct net_device_context *ndev_ctx;
> + struct net_device *vf_netdev, *net;
> + struct netvsc_device *nvdev;
> + int ret;
> +
> + net = hv_get_drvdata(dev);
> +
> + ndev_ctx = netdev_priv(net);
> + cancel_delayed_work_sync(&ndev_ctx->dwork);
> +
> + rtnl_lock();
> +
> + nvdev = rtnl_dereference(ndev_ctx->nvdev);
> + if (nvdev == NULL) {
> + ret = -ENODEV;
> + goto out;
> + }
> +
> + cancel_work_sync(&nvdev->subchan_work);

This looks redundant because netvsc_detach() cancels subchan_work.

Thanks,
- Haiyang