diff options
Diffstat (limited to 'arch/powerpc/mm/pgtable.c')
-rw-r--r-- | arch/powerpc/mm/pgtable.c | 104 |
1 files changed, 0 insertions, 104 deletions
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index 6a3997f98dfb..af40c8768a78 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -33,110 +33,6 @@ #include "mmu_decl.h" -DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); - -#ifdef CONFIG_SMP - -/* - * Handle batching of page table freeing on SMP. Page tables are - * queued up and send to be freed later by RCU in order to avoid - * freeing a page table page that is being walked without locks - */ - -static DEFINE_PER_CPU(struct pte_freelist_batch *, pte_freelist_cur); -static unsigned long pte_freelist_forced_free; - -struct pte_freelist_batch -{ - struct rcu_head rcu; - unsigned int index; - unsigned long tables[0]; -}; - -#define PTE_FREELIST_SIZE \ - ((PAGE_SIZE - sizeof(struct pte_freelist_batch)) \ - / sizeof(unsigned long)) - -static void pte_free_smp_sync(void *arg) -{ - /* Do nothing, just ensure we sync with all CPUs */ -} - -/* This is only called when we are critically out of memory - * (and fail to get a page in pte_free_tlb). - */ -static void pgtable_free_now(void *table, unsigned shift) -{ - pte_freelist_forced_free++; - - smp_call_function(pte_free_smp_sync, NULL, 1); - - pgtable_free(table, shift); -} - -static void pte_free_rcu_callback(struct rcu_head *head) -{ - struct pte_freelist_batch *batch = - container_of(head, struct pte_freelist_batch, rcu); - unsigned int i; - - for (i = 0; i < batch->index; i++) { - void *table = (void *)(batch->tables[i] & ~MAX_PGTABLE_INDEX_SIZE); - unsigned shift = batch->tables[i] & MAX_PGTABLE_INDEX_SIZE; - - pgtable_free(table, shift); - } - - free_page((unsigned long)batch); -} - -static void pte_free_submit(struct pte_freelist_batch *batch) -{ - call_rcu_sched(&batch->rcu, pte_free_rcu_callback); -} - -void pgtable_free_tlb(struct mmu_gather *tlb, void *table, unsigned shift) -{ - /* This is safe since tlb_gather_mmu has disabled preemption */ - struct pte_freelist_batch **batchp = &__get_cpu_var(pte_freelist_cur); - unsigned long pgf; - - if (atomic_read(&tlb->mm->mm_users) < 2 || - cpumask_equal(mm_cpumask(tlb->mm), cpumask_of(smp_processor_id()))){ - pgtable_free(table, shift); - return; - } - - if (*batchp == NULL) { - *batchp = (struct pte_freelist_batch *)__get_free_page(GFP_ATOMIC); - if (*batchp == NULL) { - pgtable_free_now(table, shift); - return; - } - (*batchp)->index = 0; - } - BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE); - pgf = (unsigned long)table | shift; - (*batchp)->tables[(*batchp)->index++] = pgf; - if ((*batchp)->index == PTE_FREELIST_SIZE) { - pte_free_submit(*batchp); - *batchp = NULL; - } -} - -void pte_free_finish(void) -{ - /* This is safe since tlb_gather_mmu has disabled preemption */ - struct pte_freelist_batch **batchp = &__get_cpu_var(pte_freelist_cur); - - if (*batchp == NULL) - return; - pte_free_submit(*batchp); - *batchp = NULL; -} - -#endif /* CONFIG_SMP */ - static inline int is_exec_fault(void) { return current->thread.regs && TRAP(current->thread.regs) == 0x400; |