From dd977172e3b336676f0ac0f7e51dfa8e6553a11f Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" Date: Wed, 13 Apr 2022 23:07:21 -0700 Subject: [PATCH] fork: use VMA iterator The VMA iterator is faster than the linked list and removing the linked list will shrink the vm_area_struct. Link: https://lkml.kernel.org/r/20220404143501.2016403-51-Liam.Howlett@oracle.com Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Liam R. Howlett Acked-by: Vlastimil Babka Signed-off-by: Andrew Morton --- kernel/fork.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 20890be1371bc..fa0ec07837842 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1288,13 +1288,16 @@ int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) /* Forbid mm->exe_file change if old file still mapped. */ old_exe_file = get_mm_exe_file(mm); if (old_exe_file) { + VMA_ITERATOR(vmi, mm, 0); mmap_read_lock(mm); - for (vma = mm->mmap; vma && !ret; vma = vma->vm_next) { + for_each_vma(vmi, vma) { if (!vma->vm_file) continue; if (path_equal(&vma->vm_file->f_path, - &old_exe_file->f_path)) + &old_exe_file->f_path)) { ret = -EBUSY; + break; + } } mmap_read_unlock(mm); fput(old_exe_file); -- 2.50.1