From 58d80b5599d2c7ce9a5cbe26ae5ff7e616a5824a Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Thu, 17 Feb 2022 11:24:06 +0100
Subject: [PATCH] fork: Use IS_ENABLED() in account_kernel_stack()
References: SLE Realtime Extension
Patch-mainline: v5.18-rc1
Git-commit: 0ce055f85335e48bc571114d61a70ae217039362
Not strickly needed but checking CONFIG_VMAP_STACK instead of
task_stack_vm_area()' result allows the compiler the remove the else
path in the CONFIG_VMAP_STACK case where the pointer can't be NULL.
Check for CONFIG_VMAP_STACK in order to use the proper path.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20220217102406.3697941-9-bigeasy@linutronix.de
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
kernel/fork.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/fork.c b/kernel/fork.c
index 2d2641ed0e93..f9af525cbd2d 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -483,16 +483,16 @@ void vm_area_free(struct vm_area_struct *vma)
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) {
+ if (IS_ENABLED(CONFIG_VMAP_STACK)) {
+ struct vm_struct *vm = task_stack_vm_area(tsk);
int i;
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 {
+ void *stack = task_stack_page(tsk);
+
/* All stack pages are in the same node. */
mod_lruvec_kmem_state(stack, NR_KERNEL_STACK_KB,
account * (THREAD_SIZE / 1024));