Re: [PATCH RT 04/25][RFC 3.0.23-rt39-rc1] revert-seqlock-remove-unused-functions

From: Steven Rostedt <rostedt@goodmis.org>

revert: seqlock-remove-unused-functions.patch

Revert:

Author: Thomas Gleixner [off-list ref]
Date:   Sat Jul 16 18:38:22 2011 +0200

   seqlock-remove-unused-functions.patch

   Signed-off-by: Thomas Gleixner [off-list ref]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/linux/seqlock.h |   21 +++++++++++++++++++++
 1 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index b990f6e..c6db9fb 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h

@@ -69,6 +69,17 @@ static inline void write_sequnlock(seqlock_t *sl)

       spin_unlock(&sl->lock);
 }

+static inline int write_tryseqlock(seqlock_t *sl)
+{
+       int ret = spin_trylock(&sl->lock);
+
+       if (ret) {
+               ++sl->sequence;
+               smp_wmb();
+       }
+       return ret;
+}
+
 /* Start of read calculation -- fetch last complete writer token */
 static __always_inline unsigned read_seqbegin(const seqlock_t *sl)
 {

@@ -237,4 +248,14 @@ static inline void write_seqcount_barrier(seqcount_t *s)

 #define write_sequnlock_bh(lock)                                       \
       do { write_sequnlock(lock); local_bh_enable(); } while(0)

+#define read_seqbegin_irqsave(lock, flags)                             \
+       ({ local_irq_save(flags);   read_seqbegin(lock); })
+
+#define read_seqretry_irqrestore(lock, iv, flags)                      \
+       ({                                                              \
+               int ret = read_seqretry(lock, iv);                      \
+               local_irq_restore(flags);                               \
+               ret;                                                    \
+       })
+
 #endif /* __LINUX_SEQLOCK_H */
--