[PATCH v4 49/66] bpf: Remove VMA linked list
From: Liam Howlett <hidden>
Date: 2021-12-01 14:37:59
Also in:
lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [iterator], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Yonghong Song, Linus Torvalds
From: "Liam R. Howlett" <redacted> Use vma_next() and remove reference to the start of the linked list Signed-off-by: Liam R. Howlett <redacted> --- kernel/bpf/task_iter.c | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-)
diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c
index b48750bfba5a..2d964743f1e6 100644
--- a/kernel/bpf/task_iter.c
+++ b/kernel/bpf/task_iter.c@@ -299,8 +299,8 @@ struct bpf_iter_seq_task_vma_info { }; enum bpf_task_vma_iter_find_op { - task_vma_iter_first_vma, /* use mm->mmap */ - task_vma_iter_next_vma, /* use curr_vma->vm_next */ + task_vma_iter_first_vma, /* use find_vma() with addr 0 */ + task_vma_iter_next_vma, /* use vma_next() with curr_vma */ task_vma_iter_find_vma, /* use find_vma() to find next vma */ };
@@ -400,24 +400,11 @@ task_vma_seq_get_next(struct bpf_iter_seq_task_vma_info *info) switch (op) { case task_vma_iter_first_vma: - curr_vma = curr_task->mm->mmap; + curr_vma = find_vma(curr_task->mm, 0); break; case task_vma_iter_next_vma: - curr_vma = curr_vma->vm_next; - break; case task_vma_iter_find_vma: - /* We dropped mmap_lock so it is necessary to use find_vma - * to find the next vma. This is similar to the mechanism - * in show_smaps_rollup(). - */ - curr_vma = find_vma(curr_task->mm, info->prev_vm_end - 1); - /* case 1) and 4.2) above just use curr_vma */ - - /* check for case 2) or case 4.1) above */ - if (curr_vma && - curr_vma->vm_start == info->prev_vm_start && - curr_vma->vm_end == info->prev_vm_end) - curr_vma = curr_vma->vm_next; + curr_vma = find_vma(curr_task->mm, curr_vma->vm_end); break; } if (!curr_vma) {
--
2.30.2