On Wed, Sep 21, 2016 at 10:11:54AM +0200, Christophe Leroy wrote: > Today there are two implementations of hugetlbpages which are managed > by exclusive #ifdefs: > * FSL_BOOKE: several directory entries points to the same single hugepage > * BOOK3S: one upper level directory entry points to a table of hugepages > > In preparation of implementation of hugepage support on the 8xx, we > need a mix of the two above solutions, because the 8xx needs both cases > depending on the size of pages: > * In 4k page size mode, each PGD entry covers a 4M bytes area. It means > that 2 PGD entries will be necessary to cover an 8M hugepage while a > single PGD entry will cover 8x 512k hugepages. > * In 16 page size mode, each PGD entry covers a 64M bytes area. It means > that 8x 8M hugepages will be covered by one PGD entry and 64x 512k > hugepages will be covers by one PGD entry. > > This patch: > * removes #ifdefs in favor of if/else based on the range sizes > * merges the two huge_pte_alloc() functions as they are pretty similar > * merges the two hugetlbpage_init() functions as they are pretty similar > > Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> > Reviewed-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
With this patch on e6500, running the hugetlb testsuite results in the system hanging in a storm of OOM killer invocations (I'll try to debug more deeply later). This patch also changes the default hugepage size on FSL book3e from 4M to 16M. -Scott