diff options
| author |   Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2015-12-01 09:06:45 +0530 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2015-12-14 15:19:10 +1100 |
| commit | bf680d51605662aae5482d87e0e0a54ba6db056b (patch) | |
| tree | db17e9a9754e2f9fc10daa3bbb30ece19d21ba88 /arch/powerpc/mm/hugetlbpage-hash64.c | |
| parent | powerpc/mm: Remove the dependency on pte bit position in asm code (diff) | |
| download | linux-dev-bf680d51605662aae5482d87e0e0a54ba6db056b.tar.xz linux-dev-bf680d51605662aae5482d87e0e0a54ba6db056b.zip | |
powerpc/mm: Don't track subpage valid bit in pte_t
This free up 11 bits in pte_t. In the later patch we also change
the pte_t format so that we can start supporting migration pte
at pmd level. We now track 4k subpage valid bit as below
If we have _PAGE_COMBO set, we override the _PAGE_F_GIX_SHIFT
and _PAGE_F_SECOND. Together we have 4 bits, each of them
used to indicate whether any of the 4 4k subpage in that group
is valid. ie,
[ group 1 bit ] [ group 2 bit ] ..... [ group 4 ]
[ subpage 1 - 4] [ subpage 5- 8] ..... [ subpage 13 - 16]
We still track each 4k subpage slot number and secondary hash
information in the second half of pgtable_t. Removing the subpage
tracking have some significant overhead on aim9 and ebizzy benchmark and
to support THP with 4K subpage, we do need a pgtable_t of 4096 bytes.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/hugetlbpage-hash64.c')
| -rw-r--r-- | arch/powerpc/mm/hugetlbpage-hash64.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c index d94b1af53a93..7584e8445512 100644 --- a/arch/powerpc/mm/hugetlbpage-hash64.c +++ b/arch/powerpc/mm/hugetlbpage-hash64.c @@ -91,11 +91,8 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid, pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT; /* clear HPTE slot informations in new PTE */ -#ifdef CONFIG_PPC_64K_PAGES - new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HPTE_SUB0; -#else new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE; -#endif + /* Add in WIMG bits */ rflags |= (new_pte & (_PAGE_WRITETHRU | _PAGE_NO_CACHE | _PAGE_COHERENT | _PAGE_GUARDED)); |