diff options
Diffstat (limited to 'include/asm-generic')
| -rw-r--r-- | include/asm-generic/tlb.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index ed6642ad03e..25f01d0bc14 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. */ @@ -96,6 +104,7 @@ struct mmu_gather { 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 |