On Tue, Mar 02, 2021 at 03:37:33PM +0800, Muchun Song wrote:
> The alloc_thread_stack_node() cannot guarantee that allocated stack pages
> are in the same node when CONFIG_VMAP_STACK. Because we do not specify
> __GFP_THISNODE to __vmalloc_node_range(). Fix it by caling
> mod_lruvec_page_state() for each page one by one.
Hm, I actually wonder if it makes any sense to split the stack over multiple
nodes? Maybe we should fix this instead?
>
> Fixes: 991e7673859e ("mm: memcontrol: account kernel stack per node")
> Signed-off-by: Muchun Song <songmuc...@bytedance.com>
> ---
> kernel/fork.c | 15 ++++++++++-----
> 1 file changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/fork.c b/kernel/fork.c
> index d66cd1014211..6e2201feb524 100644
> --- a/kernel/fork.c
> +++ b/kernel/fork.c
> @@ -379,14 +379,19 @@ static void account_kernel_stack(struct task_struct
> *tsk, int account)
> void *stack = task_stack_page(tsk);
> struct vm_struct *vm = task_stack_vm_area(tsk);
>
> + if (vm) {
> + int i;
>
> - /* All stack pages are in the same node. */
> - if (vm)
> - mod_lruvec_page_state(vm->pages[0], NR_KERNEL_STACK_KB,
> - account * (THREAD_SIZE / 1024));
> - else
> + BUG_ON(vm->nr_pages != THREAD_SIZE / PAGE_SIZE);
> +
> + for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++)
> + mod_lruvec_page_state(vm->pages[i], NR_KERNEL_STACK_KB,
> + account * (PAGE_SIZE / 1024));
> + } else {
> + /* All stack pages are in the same node. */
> mod_lruvec_kmem_state(stack, NR_KERNEL_STACK_KB,
> account * (THREAD_SIZE / 1024));
> + }
> }
>
> static int memcg_charge_kernel_stack(struct task_struct *tsk)
> --
> 2.11.0
>
