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

[Neil Horman <nhorman@tuxdriver.com>]

On Mon, Mar 02, 2015 at 10:18:42AM +0200, Raz Amir wrote:
> The patch I suggest is in the nic_uio freebsd kernel driver. I don't think
> that rte_log can be used there.
> I checked the contigmem freebsd driver and it uses printf.
> I can either remove those printfs, or keep them.
> I suggest keeping them as they were very helpful for understanding the flow,
> and they don't provide too much output (depending on the amount of
> interfaces connected to the nic_uio driver).
> 
You're right you can't use it, I thought it was the user space support for the
uio driver, not the kernel module


> How should I continue with this patch?
> BTW, I don't see it in incoming patches page at
> http://dpdk.org/dev/patchwork/project/dpdk/list/?page=1 
> Is it because I missed something in the code contribution instruction?
> 
> -----Original Message-----
> From: Neil Horman [mailto:nhorman@tuxdriver.com] 
> Sent: 01 March 2015 19:17
> To: Raz Amir
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH] pci: save list of detached devices, and
> re-probe during driver unload
> 
> On Sun, Mar 01, 2015 at 04:21:10PM +0200, Raz Amir wrote:
> > Can you refer me to the logging facilities you are referring to for 
> > this Freebsd driver?
> > device_probe_and_attach is an API in Freebsd kernel which is called 
> > during
> rte_log and friends.
> 
> > boot for finding the relevant driver for each device.
> > I added manual call to it in the driver unload for re-probing and 
> > re-matching the devices that were detached by the driver.
> > Before this change, you had to reboot in order to get the devices back.
> > 
> my bad, I didn't see it defined and was thinking it was removed from an
> earlier version of the dpdk.
> Neil
> 
> > -----Original Message-----
> > From: Neil Horman [mailto:nhorman@tuxdriver.com]
> > Sent: 01 March 2015 15:48
> > To: Raz Amir
> > Cc: dev@dpdk.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 <razamir22@gmail.com>
> > > ---
> > >  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;
> > >  
> > >  struct nic_uio_softc {
> > >  	device_t        dev_t;
> > > @@ -291,14 +294,35 @@ nic_uio_load(void)
> > >  		if (dev != NULL)
> > >  			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) {
> > > +
> > printf("nic_uio_load: detaching and storing dev=%p\n", dev); No 
> > printfs.  Use the logging facilities
> > 
> > > +
> > 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);
> > Dittto
> > 
> > > +							}
> > > +								
> > >  							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]);
> > Where is this defined?  It doesn't appear to be in the latest dpdk.
> > 
> > > +		printf("nic_uio_unload: done.\n");
> > > +	}
> > > +
> > > +	printf("nic_uio_unload: leaving ... \n");
> > >  }
> > >  
> > >  static int
> > > --
> > > 2.1.2
> > > 
> > > 
> > 
> > 
> 
>