diff options
Diffstat (limited to 'include/asm-generic/tlb.h')
| -rw-r--r-- | include/asm-generic/tlb.h | 33 |
1 files changed, 16 insertions, 17 deletions
diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index ed6642ad03e..5672d7ea1fa 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -78,6 +78,14 @@ struct mmu_gather_batch { #define MAX_GATHER_BATCH \ ((PAGE_SIZE - sizeof(struct mmu_gather_batch)) / sizeof(void *)) +/* + * Limit the maximum number of mmu_gather batches to reduce a risk of soft + * lockups for non-preemptible kernels on huge machines when a lot of memory + * is zapped during unmapping. + * 10K pages freed at once should be safe even without a preemption point. + */ +#define MAX_GATHER_BATCH_COUNT (10000UL/MAX_GATHER_BATCH) + /* struct mmu_gather is an opaque type used by the mm code for passing around * any data needed by arch specific code for tlb_remove_page. */ @@ -89,31 +97,22 @@ struct mmu_gather { unsigned long start; unsigned long end; unsigned int need_flush : 1, /* Did free PTEs */ - fast_mode : 1; /* No batching */ - - unsigned int fullmm; + /* we are in the middle of an operation to clear + * a full mm and can make some optimizations */ + fullmm : 1, + /* we have performed an operation which + * requires a complete flush of the tlb */ + need_flush_all : 1; struct mmu_gather_batch *active; struct mmu_gather_batch local; struct page *__pages[MMU_GATHER_BUNDLE]; + unsigned int batch_count; }; #define HAVE_GENERIC_MMU_GATHER -static inline int tlb_fast_mode(struct mmu_gather *tlb) -{ -#ifdef CONFIG_SMP - return tlb->fast_mode; -#else - /* - * For UP we don't need to worry about TLB flush - * and page free order so much.. - */ - return 1; -#endif -} - -void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, bool fullmm); +void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start, unsigned long end); void tlb_flush_mmu(struct mmu_gather *tlb); void tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end); |