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

["Raz Amir" <razamir22@gmail.com>]

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
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.

-----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
> 
>