Re: [PATCH] pci: save list of detached devices, and re-probe during driver unload

["Raz Amir" <razamir22-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

Thank you.

See answers inline (mostly ack, but not only), and I will send the updated
patch soon.

 

> -----Original Message-----

> From: Bruce Richardson [mailto:bruce.richardson-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org]

> Sent: 03 March 2015 15:33

> To: Raz Amir

> Cc: dev-VfR2kkLFssw@public.gmane.org

> Subject: Re: [dpdk-dev] [PATCH] pci: save list of detached devices, and
re-

> probe during driver unload

> 

> On Thu, Feb 26, 2015 at 06:33:20AM +0000, Raz Amir wrote:

> > Added code that saves the pointers to the detached devices, during

> > driver loading, and during driver unloading, go over the list, and

> > re-attach them by calling device_probe_and_attach on each device.

> >

> > Signed-off-by: Raz Amir < <mailto:razamir22-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
razamir22-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

> 

> Couple of minor comments below. Otherwise all looks good to me.

> 

> Acked-by: Bruce Richardson < <mailto:bruce.richardson-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
bruce.richardson-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>

> > ---

> >  lib/librte_eal/bsdapp/nic_uio/nic_uio.c | 26

> > +++++++++++++++++++++++++-

> >  1 file changed, 25 insertions(+), 1 deletion(-)

> >

> > diff --git a/lib/librte_eal/bsdapp/nic_uio/nic_uio.c

> > b/lib/librte_eal/bsdapp/nic_uio/nic_uio.c

> > index 5ae8560..7d702a5 100644

> > --- a/lib/librte_eal/bsdapp/nic_uio/nic_uio.c

> > +++ b/lib/librte_eal/bsdapp/nic_uio/nic_uio.c

> > @@ -55,6 +55,9 @@ __FBSDID("$FreeBSD$");

> >

> >  #define MAX_BARS (PCIR_MAX_BAR_0 + 1)

> >

> > +#define MAX_DETACHED_DEVICES               128

> > +static device_t detached_devices[MAX_DETACHED_DEVICES] = {}; static

> > +int last_detached = 0;

> Maybe num_detached/nb_detached or even just "detached" instead of

> "last_detached".

Ack.

 

> 

> >

> >  struct nic_uio_softc {

> >          device_t        dev_t;

> > @@ -291,14 +294,35 @@ nic_uio_load(void)

> >                          if (dev != NULL)

> 

> We are getting into some serious levels of indentation below, so maybe
flip

> this condition around and put in a "continue" instead, so that we can
dedent

> everything below that follows it.

> 

Ack.

 

> >                                          for (i = 0; i < NUM_DEVICES;
i++)

> >                                                          if
(pci_get_vendor(dev) == devices[i].vend

> &&

> > -
pci_get_device(dev) ==

> devices[i].dev)

> > +
pci_get_device(dev) ==

> devices[i].dev) {

> > +
if (last_detached+1 <

> MAX_DETACHED_DEVICES) {

> I don't think you need the +1 here.

It is needed, otherwise the last object will be added at
MAX_DETACHED_DEVICES position while the last position is
MAX_DETACHED_DEVICES-1.

However, I did change the code to:

if (last_detached < MAX_DETACHED_DEVICES-1) {

to better reflect that.

You will see it in the next patch I will send.

 

> 

> > +

>             printf("nic_uio_load: detaching and storing dev=%p\n", dev);

> > +

>             detached_devices[last_detached++] = dev;

> > +
}

> > +
else {

> > +

>             printf("nic_uio_load: reached MAX_DETACHED_DEVICES=%d.

> dev=%p won't be reattached\n",

> > +

>             MAX_DETACHED_DEVICES, dev);

> > +
}

> DPDK coding style is not to put braces around single-line statements like
this.

Ack.

 

> 

> 

> > +

> Remove whitespace from this new line.

> 

Ack.

 

> >
device_detach(dev);

> > +                                                      }

> >          }

> >  }

> >

> >  static void

> >  nic_uio_unload(void)

> >  {

> > +      int i;

> > +      printf("nic_uio_unload: entered ... \n");

> > +

> > +      for (i = 0; i < last_detached; i++) {

> > +                      printf("nic_uio_unload: calling to
device_probe_and_attach

> for dev=%p...\n",

> > +                                      detached_devices[i]);

> > +                      device_probe_and_attach(detached_devices[i]);

> > +                      printf("nic_uio_unload: done.\n");

> > +      }

> > +

> > +      printf("nic_uio_unload: leaving ... \n");

> >  }

> >

> >  static int

> > --

> > 2.1.2

> >