[PATCH 65/94] fs/proc/base: Use maple tree iterators in place of linked list

From: Liam Howlett
Date: Wed Apr 28 2021 - 11:41:14 EST


Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
fs/proc/base.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index fd46d8dd0cf4..8f62ab2e77e5 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2315,6 +2315,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
GENRADIX(struct map_files_info) fa;
struct map_files_info *p;
int ret;
+ MA_STATE(mas, NULL, 0, 0);

genradix_init(&fa);

@@ -2340,8 +2341,10 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
mmput(mm);
goto out_put_task;
}
+ rcu_read_lock();

nr_files = 0;
+ mas.tree = &mm->mm_mt;

/*
* We need two passes here:
@@ -2353,7 +2356,8 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
* routine might require mmap_lock taken in might_fault().
*/

- for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
+ pos = 2;
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (!vma->vm_file)
continue;
if (++pos <= ctx->pos)
@@ -2371,6 +2375,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
p->end = vma->vm_end;
p->mode = vma->vm_file->f_mode;
}
+ rcu_read_unlock();
mmap_read_unlock(mm);
mmput(mm);

--
2.30.2