[dpdk-dev] [PATCH] enic: corrected the usage of VFIO_PRESENT

[Sujith Sankar (ssujith)]

On 16/12/14 4:06 pm, "Burakov, Anatoly" <anatoly.burakov at intel.com> wrote:

>> -----Original Message-----
>> From: Sujith Sankar (ssujith) [mailto:ssujith at cisco.com]
>> Sent: Tuesday, December 16, 2014 10:34 AM
>> To: Burakov, Anatoly; Thomas Monjalon
>> Cc: dev at dpdk.org
>> Subject: Re: [dpdk-dev] [PATCH] enic: corrected the usage of
>>VFIO_PRESENT
>> 
>> 
>> 
>> On 16/12/14 3:52 pm, "Burakov, Anatoly" <anatoly.burakov at intel.com>
>> wrote:
>> 
>> >> On 16/12/14 4:54 am, "Thomas Monjalon"
>> <thomas.monjalon at 6wind.com>
>> >> wrote:
>> >>
>> >> >2014-12-12 13:48, Sujith Sankar:
>> >> >> This patch corrects the usage of the flag VFIO_PRESENT in enic
>> >>driver.
>> >> >
>> >> >Please, could you explain why the flag VFIO_PRESENT was not well
>> used?
>> >>
>> >> Without including eal_vfio.h, VFIO_PRESENT is not available in enic.
>> >> Hence VFIO specific code in enic was not getting compiled and some
>> >>errors  were generated during run-time.
>> >>
>> >> >
>> >> >> This has uncovered a few warnings, and this patch corrects those
>>too.
>> >> >[...]
>> >> >> --- a/lib/librte_pmd_enic/enic_main.c
>> >> >> +++ b/lib/librte_pmd_enic/enic_main.c
>> >> >> @@ -39,6 +39,7 @@
>> >> >>  #include <sys/mman.h>
>> >> >>  #include <fcntl.h>
>> >> >>  #include <libgen.h>
>> >> >> +#include <sys/ioctl.h>
>> >> >>
>> >> >>  #include <rte_pci.h>
>> >> >>  #include <rte_memzone.h>
>> >> >> @@ -46,6 +47,7 @@
>> >> >>  #include <rte_mbuf.h>
>> >> >>  #include <rte_string_fns.h>
>> >> >>  #include <rte_ethdev.h>
>> >> >> +#include <eal_vfio.h>
>> >> >
>> >> >This header was not designed to be included by PMDs.
>> >> >It will break compilation on BSD.
>> >>
>> >> Is there an alternative to make VFIO_PRESENT available in enic?
>> >> Please advise.
>> >>
>> >> Thanks,
>> >> -Sujith
>> >>
>> >> >
>> >> >>  #include "enic_compat.h"
>> >> >>  #include "enic.h"
>> >> >> @@ -561,6 +563,7 @@ enic_free_consistent(__rte_unused struct
>> >> >>rte_pci_device *hwdev,
>> >> >>  	/* Nothing to be done */
>> >> >>  }
>> >> >>
>> >> >> +#ifndef VFIO_PRESENT
>> >> >>  static void
>> >> >>  enic_intr_handler(__rte_unused struct rte_intr_handle *handle,
>> >> >>  	void *arg)
>> >> >> @@ -572,6 +575,7 @@ enic_intr_handler(__rte_unused struct
>> >> >>rte_intr_handle *handle,
>> >> >>
>> >> >>  	enic_log_q_error(enic);
>> >> >>  }
>> >> >> +#endif
>> >> >
>> >> >--
>> >> >Thomas
>> >
>> >Hi Sujith
>> >
>> >Thomas is correct, VFIO code is designed to be EAL-only (mainly because
>> >it's Linuxapp-specific, and PMD's are intended to be cross-platform at
>> >least when it comes to compilation). Whatever it is that you're working
>> >around is better fixed in the EAL itself rather than in the PMD.
>> 
>> I agree with you and Thomas.  Let me find the root cause for the false
>>trigger.
>> 
>> Thanks,
>> -Sujith
>> 
>
>You may find it in EAL VFIO interrupts code. When VFIO enables some
>interrupt types, it manually sends a trigger. Normally, this "trigger"
>just enables interrupts, but maybe for ENIC it's different. I therefore
>suggest you to look there first.

Ok.  Thanks for the info, Anatoly.
ENIC does not need that trigger.  Let me take a look at that first.

Thanks,
-Sujith

>
>Thanks,
>Anatoly