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charset="UTF-8" X-Rspamd-Queue-Id: B8F6510000D X-Rspam-User: X-Rspamd-Server: rspam07 X-Stat-Signature: g7hmjyse4zx9cid8o77637cao96csg66 X-HE-Tag: 1790617309-152209 X-HE-Meta: U2FsdGVkX1+xMOW0kp6b0xjr5nZVRFOTdy2BzLXTpghPVwiPhnKrUcTyBcn1V4plU6vp7S1AqYa04CTdacAsKbm+o6Tr9SKT6Q+PT5pAsu6jHHNfn1i5pfcYO1wVaW3LyU4TKqcQVWlab33GFBD04cY7BfhCWJ8qWoPR6a8PVmL9uQNUFiNJjIy0ZT3PSX8rKawy0mzY5z2GY+LJE7ThnVyf1/BItciPThVsVBx5+9XBVQsFVzkn3Ub3xNV8OSCIKb3QH8dYT9qw596MD+e7cQamda3sIoMCJyNMLZkU9Xm3jQkQZXHR/0Q3kofbZYE27XvAJ1gGZTlBR9ULQ6bSFrAo3cxGoNmDUzuSCl0/5HoT2XTEvTMeHydUbDWlF4uhe6rDEfQ/a0o/lE5b2ta0iD6vIru7uSr4utO4roTWoSrJl/yrSdUJ3m93jhE5C/zfBiiuY2y56a8Z5m1abDABsvxwMpX+BxB+97P67MyR1ssyOoIbCj2nqTJm3I3QX7OkLFf3Kbw2VFfPzzYBuP6ihgAjzzEClyszr+9kxiwqZwadTyFB2rXsxMzW1ml3DNZWAXxGQ9XS54PygyezTfYLtY3EhK0LNi41omC4RHHi9VrGSHqaYLzE7GACXWwvmD7h5iB2L+umfnneB7hqCvR0VMjivHut7x+bFi3mr6uO86uw2onuvpWtrDXI8hLVAlgbe4B7c5a1pFHVqiEtUkJ93G7UXLM0id+uO9kCseq6wPK8R2YHVoohrUMZqsyKqMNKohbX6Y14KPZCSk8AIS7PsCfPIExizttRARiKtLNYaBXREF/8LKpw5EJI7OKsFaz3C3JVQp5/A8gBlWamN7Bi3L/GlIpzdT0nCF0eQcViDePn+Byv7oH6XpX1ytSn5cPpmZQ6ZVCPZ6P/MByK0CafZUgkkHrWlkm7dv2nYzg0CRd7Yts9E+vNX3o+bNceWsK35kvjyX7tx2q2qvPtiZT emjRHrMQ 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Pasha Tatashin In many places number of pages in the stack is determined via (THREAD_SIZE / PAGE_SIZE). There is also a BUG_ON() that ensures that (THREAD_SIZE / PAGE_SIZE) is indeed equals to vm_area->nr_pages. In the next patches the kernel stack size will not be a compile time constant and would be less than or equal THREAD_SIZE based on a command line arg. Therefore, use vm_area->nr_pages to determine the actual number of pages allocated in stack. Signed-off-by: Pasha Tatashin [Rebased, also skipped intermediary helper variable nr_pages] Signed-off-by: Linus Walleij Signed-off-by: David Stevens [Update commit message] Signed-off-by: Mostafa Saleh --- kernel/fork.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 5ef413368912..2065693e762c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -315,9 +315,7 @@ static int memcg_charge_kernel_stack(struct vm_struct *vm_area) int ret; int nr_charged = 0; - BUG_ON(vm_area->nr_pages != THREAD_SIZE / PAGE_SIZE); - - for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) { + for (i = 0; i < vm_area->nr_pages; i++) { ret = memcg_kmem_charge_page(vm_area->pages[i], GFP_KERNEL, 0); if (ret) goto err; @@ -488,7 +486,7 @@ static void account_kernel_stack(struct task_struct *tsk, int account) struct vm_struct *vm_area = task_stack_vm_area(tsk); int i; - for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) + for (i = 0; i < vm_area->nr_pages; i++) mod_lruvec_page_state(vm_area->pages[i], NR_KERNEL_STACK_KB, account * (PAGE_SIZE / 1024)); } else { @@ -509,7 +507,7 @@ void exit_task_stack_account(struct task_struct *tsk) int i; vm_area = task_stack_vm_area(tsk); - for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) + for (i = 0; i < vm_area->nr_pages; i++) memcg_kmem_uncharge_page(vm_area->pages[i], 0); } } -- 2.56.0.rc1.315.gc6ed9934b7-goog