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 <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Alexey Kardashevskiy 2017-03-28 19:13:49 +11:00 committed by David Gibson
parent 3dc410ae83
commit a01f3432dd
1 changed files with 6 additions and 0 deletions

View File

@ -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) {