diff options
| author | Gerald Schaefer <gerald.schaefer@de.ibm.com> | 2012-10-08 16:30:07 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-09 16:22:29 +0900 |
| commit | e3ebcf64381188a2744a9829a4eb5c2b60f1974c (patch) | |
| tree | 6c2bc18729bd6fc12b93d82403fad6afec319c3b /mm/pgtable-generic.c | |
| parent | 15626062f4a98279c59a2a5208c496cf65cbf8c0 (diff) | |
| download | lwn-e3ebcf64381188a2744a9829a4eb5c2b60f1974c.tar.gz lwn-e3ebcf64381188a2744a9829a4eb5c2b60f1974c.zip | |
thp: remove assumptions on pgtable_t type
The thp page table pre-allocation code currently assumes that pgtable_t is
of type "struct page *". This may not be true for all architectures, so
this patch removes that assumption by replacing the functions
prepare_pmd_huge_pte() and get_pmd_huge_pte() with two new functions that
can be defined architecture-specific.
It also removes two VM_BUG_ON checks for page_count() and page_mapcount()
operating on a pgtable_t. Apart from the VM_BUG_ON removal, there will be
no functional change introduced by this patch.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/pgtable-generic.c')
| -rw-r--r-- | mm/pgtable-generic.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index 74c0ddaa6fa0..29867e083d37 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -120,3 +120,42 @@ void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif + +#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +void pgtable_trans_huge_deposit(struct mm_struct *mm, pgtable_t pgtable) +{ + assert_spin_locked(&mm->page_table_lock); + + /* FIFO */ + if (!mm->pmd_huge_pte) + INIT_LIST_HEAD(&pgtable->lru); + else + list_add(&pgtable->lru, &mm->pmd_huge_pte->lru); + mm->pmd_huge_pte = pgtable; +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#endif + +#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +/* no "address" argument so destroys page coloring of some arch */ +pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm) +{ + pgtable_t pgtable; + + assert_spin_locked(&mm->page_table_lock); + + /* FIFO */ + pgtable = mm->pmd_huge_pte; + if (list_empty(&pgtable->lru)) + mm->pmd_huge_pte = NULL; + else { + mm->pmd_huge_pte = list_entry(pgtable->lru.next, + struct page, lru); + list_del(&pgtable->lru); + } + return pgtable; +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#endif |