commit 21b00d2d94717fa4273071264cf9f6191788743c
author Thomas Gleixner <tglx@linutronix.de> Fri Mar 18 10:11:25 2011 +0100
committer Steven Rostedt <rostedt@goodmis.org> Wed Nov 13 11:21:01 2013 -0500
tree fd28faa147a81ab7416dcb9af1101d3bbb29bbf8
parent c32961f6f71e32511233beb9f671fbc728ca70a9

fs: jbd/jbd2: Make state lock and journal head lock rt safe

bit_spin_locks break under RT.

Based on a previous patch from Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

--

 include/linux/buffer_head.h |   10 ++++++++++
 include/linux/jbd_common.h  |   24 ++++++++++++++++++++++++
 2 files changed, 34 insertions(+)

include/linux/buffer_head.h

diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index 152e5dc..2f4697c 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -76,6 +76,11 @@
 	atomic_t b_count;		/* users using this buffer_head */
 #ifdef CONFIG_PREEMPT_RT_BASE
 	spinlock_t b_uptodate_lock;
+#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || \
+    defined(CONFIG_JBD2) || defined(CONFIG_JBD2_MODULE)
+	spinlock_t b_state_lock;
+	spinlock_t b_journal_head_lock;
+#endif
 #endif
 };
 
@@ -107,6 +112,11 @@
 {
 #ifdef CONFIG_PREEMPT_RT_BASE
 	spin_lock_init(&bh->b_uptodate_lock);
+#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || \
+    defined(CONFIG_JBD2) || defined(CONFIG_JBD2_MODULE)
+	spin_lock_init(&bh->b_state_lock);
+	spin_lock_init(&bh->b_journal_head_lock);
+#endif
 #endif
 }
 

include/linux/jbd_common.h

diff --git a/include/linux/jbd_common.h b/include/linux/jbd_common.h
index 6133679..0dbc151 100644
--- a/include/linux/jbd_common.h
+++ b/include/linux/jbd_common.h
@@ -39,32 +39,56 @@
 
 static inline void jbd_lock_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
 	bit_spin_lock(BH_State, &bh->b_state);
+#else
+	spin_lock(&bh->b_state_lock);
+#endif
 }
 
 static inline int jbd_trylock_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
 	return bit_spin_trylock(BH_State, &bh->b_state);
+#else
+	return spin_trylock(&bh->b_state_lock);
+#endif
 }
 
 static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
 	return bit_spin_is_locked(BH_State, &bh->b_state);
+#else
+	return spin_is_locked(&bh->b_state_lock);
+#endif
 }
 
 static inline void jbd_unlock_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
 	bit_spin_unlock(BH_State, &bh->b_state);
+#else
+	spin_unlock(&bh->b_state_lock);
+#endif
 }
 
 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
 	bit_spin_lock(BH_JournalHead, &bh->b_state);
+#else
+	spin_lock(&bh->b_journal_head_lock);
+#endif
 }
 
 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
 	bit_spin_unlock(BH_JournalHead, &bh->b_state);
+#else
+	spin_unlock(&bh->b_journal_head_lock);
+#endif
 }
 
 #endif