On 10/14/2019 3:43 PM, Bruce Richardson wrote: > On Thu, Oct 03, 2019 at 02:23:07PM +0100, Loftus, Ciara wrote: >> >> >>> -----Original Message----- From: Stephen Hemminger >>> <step...@networkplumber.org> Sent: Monday 30 September 2019 18:12 To: >>> Loftus, Ciara <ciara.lof...@intel.com> Cc: dev@dpdk.org; Ye, Xiaolong >>> <xiaolong...@intel.com>; Laatz, Kevin <kevin.la...@intel.com>; >>> Richardson, Bruce <bruce.richard...@intel.com> Subject: Re: [dpdk-dev] >>> [PATCH v2 2/3] net/af_xdp: support pinning of IRQs >>> >>> On Mon, 30 Sep 2019 16:42:04 +0000 Ciara Loftus >>> <ciara.lof...@intel.com> wrote: >>> >>>> +/* drivers supported for the queue_irq option */ +enum >>>> supported_drivers { + I40E_DRIVER, + IXGBE_DRIVER, + >>>> MLX5_DRIVER, + NUM_DRIVERS +}; >>> >>> Anything device specific like this raises a red flag to me. >>> >>> This regex etc, seems like a huge hack. Is there a better way using >>> irqbalance and smp_affinity in kernel drivers? >>> >>> NACK >> >> Hi Stephen, >> >> Thanks for looking at the patch. I understand your concern however >> unfortunately I haven't been able to identify a way to achieve the >> desired outcome by using your suggestions of irqbalance and smp_affinity. >> Did you have something specific in mind or are aware of any generic way >> of retrieving interrupt numbers for NICs regardless of vendor or range? >> >> I think this feature is really important for the usability of this PMD. >> Without it, to configure the IRQs the user has to open up >> /proc/interrupts, trawl through it and identify the correct IRQ number >> for their given NIC and qid (the format for which is unlikely to be known >> off-hand), and manually pin them by writing the appropriate values in the >> appropriate format to the appropriate file - prone to error if not >> automated IMO. If the user fails to set the affinity it's probably fine >> for a single pmd, however with multiple pmds all irqs will by default >> land on core 0 and lead to terrible performance. >> >> It should be possible to rework the code to remove the regexes and use a >> direct string compare. Would that make the solution more palatable? >> > > Hi Ciara, Stephen, > > is there any way forward on this patch? > > From my experience with using AF_XDP the pinning of interrupts is both > necessary for performance and sadly rather awkward to implement in > practice. If we can't find a better way to do this, I think merging this > patch is the best thing to do. It may be a bit messy, but the overall user > experience should be far improved over not having it. >
Can we have this external to the PMD, like a helper script that run after you start the DPDK app?