From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next-2.6] be2net: add multiple RX queue support
Date: Thu, 30 Sep 2010 17:39:57 -0700 (PDT)
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References: <20100929120113.GA16206@emulex.com>
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To: sathya.perla@emulex.com
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From: Sathya Perla <sathya.perla@emulex.com>
Date: Wed, 29 Sep 2010 17:31:13 +0530

> @@ -78,6 +78,13 @@ static inline char *nic_name(struct pci_dev *pdev)
>  #define MCC_Q_LEN		128	/* total size not to exceed 8 pages */
>  #define MCC_CQ_LEN		256
>  
> +#ifdef CONFIG_PPC64			/* ppc platforms support only max of */
> +#define NUM_RSS_QS		2	/* 4 msix vectors per pci function   */
> +#else
> +#define NUM_RSS_QS		4	/* BE limit is 4 queues/port	     */
> +#endif

If the first hunk I see in a patch is something like this, it is
not a good sign.

This is something you need to discover dynamically, and the MSI-X
vector enable functions in the kernel allow you to do this just fine.

Look at what other drivers do, they have a specific number of vectora
they try to obtain using pci_enable_msix(), and if that fails they
decrease the vector count until they are able to succeed.