Adds config option LOCKLESS_PAGE_TABLE_WALK_TRACKING to make possible enabling tracking lockless pagetable walks directly from kernel config. Signed-off-by: Leonardo Bras <leonardo@xxxxxxxxxxxxx> --- mm/Kconfig | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/mm/Kconfig b/mm/Kconfig index a5dae9a7eb51..00f487a0122f 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -736,4 +736,15 @@ config ARCH_HAS_PTE_SPECIAL config ARCH_HAS_HUGEPD bool +config LOCKLESS_PAGE_TABLE_WALK_TRACKING + bool "Track (and optimize) lockless page table walks" + default n + + help + Maintain a reference count of active lockless page table + walkers. This adds 4 bytes to struct mm size, and two atomic + operations to calls such as get_user_pages_fast(). Some + architectures can optimize lockless page table operations if + this is enabled. + endmenu -- 2.20.1
