On Tue Jun 27, 2017 at 09:39:13AM +0100, Will Deacon wrote: > On Tue, Jun 27, 2017 at 10:41:55AM +0530, Linu Cherian wrote: > > On Fri Jun 23, 2017 at 05:04:05PM +0530, Linu Cherian wrote: > > > On Fri Jun 23, 2017 at 11:35:25AM +0100, Robin Murphy wrote: > > > > Note that on a coherent platform like ThunderX that's as good as just > > > > deleting it, because you'll never execute the case below. However, on > > > > reflection I think it can at least safely be downgraded to dma_wmb() > > > > (i.e. DMB) rather than a full DSB - would you be able to test what > > > > difference that makes? > > > > > > The testing was done on Thunderx 1, which has a non coherent page table > > > walk. > > > Yes, downgrading to dma_wmb() helps. With this change, performance is > > > back to v1. > > > > > > > Should i send a patch for this ? > > I already did it: > > https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/commit/?h=for-joerg/arm-smmu/updates&id=77f3445866c39d8866b31d8d9fa47c7c20938e05 > > Will > > _______________________________________________ > linux-arm-kernel mailing list > [email protected] > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Thanks Will. -- Linu cherian _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
