author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> 2017-10-20 11:29:53 +0200
committer: Minda Chen <minda.chen@starfivetech.com> 2023-11-06 19:24:46 +0800
commit: 7b829c0257ae96e05c966c3b1b63a8a95deab891
parent: f530d6efc0c938981cda16b9946c73546643c9e6
Commit Summary:
Diffstat:
1 file changed, 9 insertions, 1 deletion
diff --git a/fs/dcache.c b/fs/dcache.c
index 93165b9ba3b0..02db80f2817f 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2537,7 +2537,13 @@ EXPORT_SYMBOL(d_rehash);
static inline unsigned start_dir_add(struct inode *dir)
{
-
+ /*
+ * The caller has a spinlock_t (dentry::d_lock) acquired which disables
+ * preemption on !PREEMPT_RT. On PREEMPT_RT the lock does not disable
+ * preemption and it has be done explicitly.
+ */
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ preempt_disable();
for (;;) {
unsigned n = dir->i_dir_seq;
if (!(n & 1) && cmpxchg(&dir->i_dir_seq, n, n + 1) == n)
@@ -2549,6 +2555,8 @@ static inline unsigned start_dir_add(struct inode *dir)
static inline void end_dir_add(struct inode *dir, unsigned n)
{
smp_store_release(&dir->i_dir_seq, n + 2);
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ preempt_enable();
}
static void d_wait_lookup(struct dentry *dentry)