Re: [PATCH v2 6/8] fs: convert process/thread iterators to for_each_*_rculock
From: sashiko-bot@kernel.org
Date: 2026-09-07 08:23:35
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [Low] Mixing scope-based cleanup (scoped_guard) with goto-based error handling in the same function. -- commit e0076a589e993892daf78cfc52036d64c5fb68e6 Author: Ye Liu [off-list ref] fs: convert process/thread iterators to for_each_*_rculock This commit replaces manual rcu_read_lock() and rcu_read_unlock() pairs combined with process iterators in the fs/ directory with for_each_*_rculock() macros. These new macros scope the RCU read lock to the loop body using scoped_guard(rcu).
quoted hunk ↗ jump to hunk
diff --git a/fs/proc/base.c b/fs/proc/base.c index 58be389424605..2c47d838a1c76 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c
[ ... ]
quoted hunk ↗ jump to hunk
@@ -1161,8 +1161,7 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) if (mm) { struct task_struct *p; - rcu_read_lock(); - for_each_process(p) { + for_each_process_rculock(p) {
[Severity: Low]
Does this code mix scope-based cleanup with goto-based error handling?
Looking at __set_oom_adj(), the function still uses goto err_unlock; for
error paths earlier in the function:
fs/proc/base.c:__set_oom_adj() {
...
if (legacy) {
if (oom_adj < task->signal->oom_score_adj &&
!capable(CAP_SYS_RESOURCE)) {
err = -EACCES;
goto err_unlock;
}
...
}
The newly introduced for_each_process_rculock() macro expands to use
scoped_guard(rcu). The cleanup subsystem guidelines explicitly state that a
function should either convert all resources that need cleanup to scope-based
cleanup, or convert none of them, to avoid confusing ownership semantics.
Could this function be fully converted, or should the rcu_read_lock() remain
manual here until the rest of the error handling is updated?
if (same_thread_group(task, p)) continue;
[ ... ] -- Sashiko AI review · https://sashiko.dev/#/patchset/20260907081334.1152889-1-ye.liu@linux.dev?part=6