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Diffstat (limited to 'fs/xfs/linux-2.6/mrlock.h')
-rw-r--r--fs/xfs/linux-2.6/mrlock.h60
1 files changed, 24 insertions, 36 deletions
diff --git a/fs/xfs/linux-2.6/mrlock.h b/fs/xfs/linux-2.6/mrlock.h
index c110bb0..ff6a198 100644
--- a/fs/xfs/linux-2.6/mrlock.h
+++ b/fs/xfs/linux-2.6/mrlock.h
@@ -20,29 +20,24 @@
#include <linux/rwsem.h>
-enum { MR_NONE, MR_ACCESS, MR_UPDATE };
-
typedef struct {
struct rw_semaphore mr_lock;
+#ifdef DEBUG
int mr_writer;
+#endif
} mrlock_t;
+#ifdef DEBUG
#define mrinit(mrp, name) \
do { (mrp)->mr_writer = 0; init_rwsem(&(mrp)->mr_lock); } while (0)
+#else
+#define mrinit(mrp, name) \
+ do { init_rwsem(&(mrp)->mr_lock); } while (0)
+#endif
+
#define mrlock_init(mrp, t,n,s) mrinit(mrp, n)
#define mrfree(mrp) do { } while (0)
-static inline void mraccess(mrlock_t *mrp)
-{
- down_read(&mrp->mr_lock);
-}
-
-static inline void mrupdate(mrlock_t *mrp)
-{
- down_write(&mrp->mr_lock);
- mrp->mr_writer = 1;
-}
-
static inline void mraccess_nested(mrlock_t *mrp, int subclass)
{
down_read_nested(&mrp->mr_lock, subclass);
@@ -51,10 +46,11 @@ static inline void mraccess_nested(mrlock_t *mrp, int subclass)
static inline void mrupdate_nested(mrlock_t *mrp, int subclass)
{
down_write_nested(&mrp->mr_lock, subclass);
+#ifdef DEBUG
mrp->mr_writer = 1;
+#endif
}
-
static inline int mrtryaccess(mrlock_t *mrp)
{
return down_read_trylock(&mrp->mr_lock);
@@ -64,39 +60,31 @@ static inline int mrtryupdate(mrlock_t *mrp)
{
if (!down_write_trylock(&mrp->mr_lock))
return 0;
+#ifdef DEBUG
mrp->mr_writer = 1;
+#endif
return 1;
}
-static inline void mrunlock(mrlock_t *mrp)
+static inline void mrunlock_excl(mrlock_t *mrp)
{
- if (mrp->mr_writer) {
- mrp->mr_writer = 0;
- up_write(&mrp->mr_lock);
- } else {
- up_read(&mrp->mr_lock);
- }
+#ifdef DEBUG
+ mrp->mr_writer = 0;
+#endif
+ up_write(&mrp->mr_lock);
}
-static inline void mrdemote(mrlock_t *mrp)
+static inline void mrunlock_shared(mrlock_t *mrp)
{
- mrp->mr_writer = 0;
- downgrade_write(&mrp->mr_lock);
+ up_read(&mrp->mr_lock);
}
-#ifdef DEBUG
-/*
- * Debug-only routine, without some platform-specific asm code, we can
- * now only answer requests regarding whether we hold the lock for write
- * (reader state is outside our visibility, we only track writer state).
- * Note: means !ismrlocked would give false positives, so don't do that.
- */
-static inline int ismrlocked(mrlock_t *mrp, int type)
+static inline void mrdemote(mrlock_t *mrp)
{
- if (mrp && type == MR_UPDATE)
- return mrp->mr_writer;
- return 1;
-}
+#ifdef DEBUG
+ mrp->mr_writer = 0;
#endif
+ downgrade_write(&mrp->mr_lock);
+}
#endif /* __XFS_SUPPORT_MRLOCK_H__ */