[RFC PATCH 04/13] rculist_bl.h: Fix parentheses around macro pointer parameter use

From: Mathieu Desnoyers
Date: Thu May 04 2023 - 16:32:39 EST


Add missing parentheses around use of macro argument "tpos" in those
patterns to ensure operator precedence behaves as expected:

- typeof(*tpos)
- pos->next
- x && y is changed for (x) && (y).

The typeof(*tpos) lack of parentheses around "tpos" is not an issue per se
in the specific macros modified here because "tpos" is used as an lvalue,
which should prevent use of any operator causing issue. Still add the
extra parentheses for consistency.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Frederic Weisbecker <frederic@xxxxxxxxxx>
Cc: Neeraj Upadhyay <quic_neeraju@xxxxxxxxxxx>
Cc: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx>
Cc: Josh Triplett <josh@xxxxxxxxxxxxxxxx>
Cc: Boqun Feng <boqun.feng@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx>
Cc: Zqiang <qiang1.zhang@xxxxxxxxx>
Cc: rcu@xxxxxxxxxxxxxxx
---
include/linux/rculist_bl.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/rculist_bl.h b/include/linux/rculist_bl.h
index 0b952d06eb0b..798c0a03bf5c 100644
--- a/include/linux/rculist_bl.h
+++ b/include/linux/rculist_bl.h
@@ -94,8 +94,8 @@ static inline void hlist_bl_add_head_rcu(struct hlist_bl_node *n,
*/
#define hlist_bl_for_each_entry_rcu(tpos, pos, head, member) \
for (pos = hlist_bl_first_rcu(head); \
- pos && \
- ({ tpos = hlist_bl_entry(pos, typeof(*tpos), member); 1; }); \
- pos = rcu_dereference_raw(pos->next))
+ (pos) && \
+ ({ tpos = hlist_bl_entry(pos, typeof(*(tpos)), member); 1; }); \
+ pos = rcu_dereference_raw((pos)->next))

#endif
--
2.25.1