Messages in this thread | | | Date | Mon, 7 Oct 2013 09:50:57 -0700 | From | Jon Mason <> | Subject | Re: [PATCH RFC 54/77] ntb: Ensure number of MSIs on SNB is enough for the link interrupt |
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On Sat, Oct 05, 2013 at 11:43:04PM +0200, Alexander Gordeev wrote: > On Wed, Oct 02, 2013 at 05:48:05PM -0700, Jon Mason wrote: > > On Wed, Oct 02, 2013 at 12:49:10PM +0200, Alexander Gordeev wrote: > > > Signed-off-by: Alexander Gordeev <agordeev@redhat.com> > > > --- > > > drivers/ntb/ntb_hw.c | 2 +- > > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > > > diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c > > > index de2062c..eccd5e5 100644 > > > --- a/drivers/ntb/ntb_hw.c > > > +++ b/drivers/ntb/ntb_hw.c > > > @@ -1066,7 +1066,7 @@ static int ntb_setup_msix(struct ntb_device *ndev) > > > /* On SNB, the link interrupt is always tied to 4th vector. If > > > * we can't get all 4, then we can't use MSI-X. > > > */ > > > - if (ndev->hw_type != BWD_HW) { > > > + if ((rc < SNB_MSIX_CNT) && (ndev->hw_type != BWD_HW)) { > > > > Nack, this check is unnecessary. > > If SNB can do more than SNB_MSIX_CNT MSI-Xs then this check is needed > to enable less than maximum MSI-Xs in case the maximum was not allocated. > Otherwise SNB will fallback to single MSI instead of multiple MSI-Xs.
Per the comment in the code snippet above, "If we can't get all 4, then we can't use MSI-X". There is already a check to see if more than 4 were acquired. So it's not possible to hit this. Even if it was, don't use SNB_MSIX_CNT here (limits.msix_cnt is the preferred variable). Also, the "()" are unnecessary.
Thanks, Jon
> -- > Regards, > Alexander Gordeev > agordeev@redhat.com
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