Commit 93f6d4e1 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

dentry: Use preempt_[dis|en]able_nested() 



Replace the open coded CONFIG_PREEMPT_RT conditional
preempt_disable/enable() with the new helper.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarChristian Brauner (Microsoft) <brauner@kernel.org>
Link: https://lore.kernel.org/r/20220825164131.402717-3-bigeasy@linutronix.de
parent 555bb4cc

fs/dcache.c

+2 −11
Original line number Diff line number Diff line
@@ -2597,15 +2597,7 @@ EXPORT_SYMBOL(d_rehash); 


static inline unsigned start_dir_add(struct inode *dir)

{

	/*

	 * The caller holds a spinlock (dentry::d_lock). On !PREEMPT_RT

	 * kernels spin_lock() implicitly disables preemption, but not on

	 * PREEMPT_RT.  So for RT it has to be done explicitly to protect

	 * the sequence count write side critical section against a reader

	 * or another writer preempting, which would result in a live lock.

	 */

	if (IS_ENABLED(CONFIG_PREEMPT_RT))

		preempt_disable();

	preempt_disable_nested();

	for (;;) {

		unsigned n = dir->i_dir_seq;

		if (!(n & 1) && cmpxchg(&dir->i_dir_seq, n, n + 1) == n)
@@ -2618,8 +2610,7 @@ static inline void end_dir_add(struct inode *dir, unsigned int n, 
			       wait_queue_head_t *d_wait)

{

	smp_store_release(&dir->i_dir_seq, n + 2);

	if (IS_ENABLED(CONFIG_PREEMPT_RT))

		preempt_enable();

	preempt_enable_nested();

	wake_up_all(d_wait);

}