From a01f3432dd005fc3f216fe3e2b88dc986f0474a9 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Tue, 28 Mar 2017 19:13:49 +1100 Subject: spapr_pci: Warn when RAM page size is not enabled in IOMMU page mask If a page size used by QEMU is not enabled in the PHB IOMMU page mask, in-kernel acceleration of TCE handling won't be enabled and performance might be slower than expected. This prints a warning if system page size is not enabled. This should print a warning if huge pages are enabled but sphb.pgsz still uses the default value of 4K|64K. Signed-off-by: Alexey Kardashevskiy Signed-off-by: David Gibson --- hw/ppc/spapr_pci.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'hw/ppc') diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c index 98c52e4..097ebdd 100644 --- a/hw/ppc/spapr_pci.c +++ b/hw/ppc/spapr_pci.c @@ -1771,6 +1771,12 @@ static void spapr_phb_realize(DeviceState *dev, Error **errp) } /* DMA setup */ + if ((sphb->page_size_mask & qemu_getrampagesize()) == 0) { + error_report("System page size 0x%lx is not enabled in page_size_mask " + "(0x%"PRIx64"). Performance may be slow", + qemu_getrampagesize(), sphb->page_size_mask); + } + for (i = 0; i < windows_supported; ++i) { tcet = spapr_tce_new_table(DEVICE(sphb), sphb->dma_liobn[i]); if (!tcet) { -- cgit v1.1