Re: [PATCH] pcnet32 driver NAPI support

[Pavel Machek <pavel@ucw.cz>]

Hi!

> I have made a diff against 2.6.16.20 and 2.6.17-rc6.
> 
> Comments would be very welcome.
> 
> Signed-off-by: Len Sorensen <lsorense@csclub.uwaterloo.ca>
> 
> Len Sorensen

> diff -ruN linux-2.6.16.20/drivers/net/Kconfig linux-2.6.16.20.pcnet32napi/drivers/net/Kconfig
> --- linux-2.6.16.20/drivers/net/Kconfig	2006-06-05 13:18:23.000000000 -0400
> +++ linux-2.6.16.20.pcnet32napi/drivers/net/Kconfig	2006-06-07 11:19:54.000000000 -0400
> @@ -1272,6 +1272,23 @@
>  	  <file:Documentation/networking/net-modules.txt>. The module
>  	  will be called pcnet32.
>  
> +config PCNET32_NAPI
> +	bool "Use NAPI RX polling "
> +	depends on PCNET32
> +	help
> +	  NAPI is a new driver API designed to reduce CPU and interrupt load
> +	  when the driver is receiving lots of packets from the card. It is
> +	  still somewhat experimental and thus not yet enabled by default.
> +
> +	  If your estimated Rx load is 10kpps or more, or if the card will be
> +	  deployed on potentially unfriendly networks (e.g. in a firewall),
> +	  then say Y here.
> +
> +	  See <file:Documentation/networking/NAPI_HOWTO.txt> for more
> +	  information.
> +
> +	  If in doubt, say N.
> +
>  config AMD8111_ETH
>  	tristate "AMD 8111 (new PCI lance) support"
>  	depends on NET_PCI && PCI
> diff -ruN linux-2.6.16.20/drivers/net/pcnet32.c linux-2.6.16.20.pcnet32napi/drivers/net/pcnet32.c
> --- linux-2.6.16.20/drivers/net/pcnet32.c	2006-06-05 13:18:23.000000000 -0400
> +++ linux-2.6.16.20.pcnet32napi/drivers/net/pcnet32.c	2006-06-07 12:00:36.000000000 -0400
> @@ -21,9 +21,15 @@
>   *
>   *************************************************************************/
>  
> +#include <linux/config.h>
> +
> +#ifdef CONFIG_PCNET32_NAPI
> +#define DRV_NAME	"pcnet32napi"
> +#else
>  #define DRV_NAME	"pcnet32"
> -#define DRV_VERSION	"1.31c"
> -#define DRV_RELDATE	"01.Nov.2005"
> +#endif
> +#define DRV_VERSION	"1.31d"
> +#define DRV_RELDATE	"06.Jun.2006"
>  #define PFX		DRV_NAME ": "
>  
>  static const char *version =
> @@ -265,6 +271,7 @@
>   * v1.31c  01 Nov 2005 Don Fry Allied Telesyn 2700/2701 FX are 100Mbit only.
>   *	   Force 100Mbit FD if Auto (ASEL) is selected.
>   *	   See Bugzilla 2669 and 4551.
> + * v1.31d  06 Jun 2006 Len Sorensen added NAPI support.
>   */
>  
>  
> @@ -383,6 +390,7 @@
>      struct mii_if_info	mii_if;
>      struct timer_list	watchdog_timer;
>      struct timer_list	blink_timer;
> +    struct timer_list	oom_timer;
>      u32			msg_enable;	/* debug message level */
>  };
>  
> @@ -392,7 +400,13 @@
>  static int  pcnet32_open(struct net_device *);
>  static int  pcnet32_init_ring(struct net_device *);
>  static int  pcnet32_start_xmit(struct sk_buff *, struct net_device *);
> +#ifdef CONFIG_PCNET32_NAPI
> +void disable_rx_and_norxbuff_ints(struct net_device *dev);
> +void enable_rx_and_norxbuff_ints(struct net_device *dev);
> +static int  pcnet32_poll(struct net_device *, int *budget);
> +#else
>  static int  pcnet32_rx(struct net_device *);
> +#endif
>  static void pcnet32_tx_timeout (struct net_device *dev);
>  static irqreturn_t pcnet32_interrupt(int, void *, struct pt_regs *);
>  static int  pcnet32_close(struct net_device *);
> @@ -422,6 +436,174 @@
>      PCI_ADDR0=0x10<<0, PCI_ADDR1=0x10<<1, PCI_ADDR2=0x10<<2, PCI_ADDR3=0x10<<3,
>  };
>  
> +#ifdef CONFIG_PCNET32_NAPI
> +void oom_timer(unsigned long data)
> +{
> +    struct net_device *dev = (struct net_device *)data;
> +    struct pcnet32_private *lp = dev->priv;
> +    lp->rl_active = 0;
> +    netif_rx_schedule(dev);
> +}
> +
> +static
> +int pcnet32_poll(struct net_device *dev, int *budget)
> +{
> +    struct pcnet32_private *lp = dev->priv;
> +    ulong ioaddr = dev->base_addr;
> +
> +    int entry = lp->cur_rx & lp->rx_mod_mask;
> +    int rx_work_limit = dev->quota;
> +    int received = 0;
> +
> +    if (!netif_running(dev))
> +	goto done;
> +
> +    do {
> +	// Clear RX interrupts
> +	lp->a.write_csr (ioaddr, 0, 0x1400);

Please indent with tabs (according to coding style) and avoid using //
comments.
									Pavel
-- 
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