Having the mrlock_t doesn't provide any benefit since rwsem is perfectly
equipped to answer the question whether a rwsem is held for write or
not. Exploit this fact to convert the i_lock/i_mmaplock to direct
semaphores, thus making mrlock unused. This removes a level of
indirection internal to xfs but also paves the way to lifting i_mmaplock
to VFS in the future.
Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
---
fs/xfs/xfs_inode.c | 41 +++++++++++++++++++++--------------------
fs/xfs/xfs_inode.h | 6 +++---
fs/xfs/xfs_super.c | 7 ++-----
3 files changed, 26 insertions(+), 28 deletions(-)
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 499e63da935c..dcf216eb7505 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -4,6 +4,7 @@
* All Rights Reserved.
*/
#include <linux/iversion.h>
+#include <linux/rwsem.h>
#include "xfs.h"
#include "xfs_fs.h"
@@ -191,14 +192,14 @@ xfs_ilock(
}
if (lock_flags & XFS_MMAPLOCK_EXCL)
- mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
+ down_write_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
else if (lock_flags & XFS_MMAPLOCK_SHARED)
- mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
+ down_read_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
if (lock_flags & XFS_ILOCK_EXCL)
- mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
+ down_write_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
else if (lock_flags & XFS_ILOCK_SHARED)
- mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
+ down_read_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
}
/*
@@ -242,27 +243,27 @@ xfs_ilock_nowait(
}
if (lock_flags & XFS_MMAPLOCK_EXCL) {
- if (!mrtryupdate(&ip->i_mmaplock))
+ if (!down_write_trylock(&ip->i_mmaplock))
goto out_undo_iolock;
} else if (lock_flags & XFS_MMAPLOCK_SHARED) {
- if (!mrtryaccess(&ip->i_mmaplock))
+ if (!down_read_trylock(&ip->i_mmaplock))
goto out_undo_iolock;
}
if (lock_flags & XFS_ILOCK_EXCL) {
- if (!mrtryupdate(&ip->i_lock))
+ if (!down_write_trylock(&ip->i_lock))
goto out_undo_mmaplock;
} else if (lock_flags & XFS_ILOCK_SHARED) {
- if (!mrtryaccess(&ip->i_lock))
+ if (!down_read_trylock(&ip->i_lock))
goto out_undo_mmaplock;
}
return 1;
out_undo_mmaplock:
if (lock_flags & XFS_MMAPLOCK_EXCL)
- mrunlock_excl(&ip->i_mmaplock);
+ up_write(&ip->i_mmaplock);
else if (lock_flags & XFS_MMAPLOCK_SHARED)
- mrunlock_shared(&ip->i_mmaplock);
+ up_read(&ip->i_mmaplock);
out_undo_iolock:
if (lock_flags & XFS_IOLOCK_EXCL)
up_write(&VFS_I(ip)->i_rwsem);
@@ -309,14 +310,14 @@ xfs_iunlock(
up_read(&VFS_I(ip)->i_rwsem);
if (lock_flags & XFS_MMAPLOCK_EXCL)
- mrunlock_excl(&ip->i_mmaplock);
+ up_write(&ip->i_mmaplock);
else if (lock_flags & XFS_MMAPLOCK_SHARED)
- mrunlock_shared(&ip->i_mmaplock);
+ up_read(&ip->i_mmaplock);
if (lock_flags & XFS_ILOCK_EXCL)
- mrunlock_excl(&ip->i_lock);
+ up_write(&ip->i_lock);
else if (lock_flags & XFS_ILOCK_SHARED)
- mrunlock_shared(&ip->i_lock);
+ up_read(&ip->i_lock);
trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
}
@@ -335,9 +336,9 @@ xfs_ilock_demote(
~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
if (lock_flags & XFS_ILOCK_EXCL)
- mrdemote(&ip->i_lock);
+ downgrade_write(&ip->i_lock);
if (lock_flags & XFS_MMAPLOCK_EXCL)
- mrdemote(&ip->i_mmaplock);
+ downgrade_write(&ip->i_mmaplock);
if (lock_flags & XFS_IOLOCK_EXCL)
downgrade_write(&VFS_I(ip)->i_rwsem);
@@ -359,14 +360,14 @@ xfs_isilocked(
{
if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
if (!(lock_flags & XFS_ILOCK_SHARED))
- return !!ip->i_lock.mr_writer;
- return rwsem_is_locked(&ip->i_lock.mr_lock);
+ return is_rwsem_write_locked(&ip->i_lock);
+ return rwsem_is_locked(&ip->i_lock);
}
if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
if (!(lock_flags & XFS_MMAPLOCK_SHARED))
- return !!ip->i_mmaplock.mr_writer;
- return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
+ return is_rwsem_write_locked(&ip->i_mmaplock);
+ return rwsem_is_locked(&ip->i_mmaplock);
}
if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index eca333f5f715..dd1d81afc4ce 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -39,8 +39,8 @@ typedef struct xfs_inode {
/* Transaction and locking information. */
struct xfs_inode_log_item *i_itemp; /* logging information */
- mrlock_t i_lock; /* inode lock */
- mrlock_t i_mmaplock; /* inode mmap IO lock */
+ struct rw_semaphore i_lock; /* inode lock */
+ struct rw_semaphore i_mmaplock; /* inode mmap IO lock */
atomic_t i_pincount; /* inode pin count */
/*
@@ -310,7 +310,7 @@ static inline bool xfs_inode_has_bigtime(struct xfs_inode *ip)
* 5 PARENT subclass (not nestable)
* 6 RTBITMAP subclass (not nestable)
* 7 RTSUM subclass (not nestable)
- *
+ *
*/
#define XFS_IOLOCK_SHIFT 16
#define XFS_IOLOCK_MAX_SUBCLASS 3
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 813be879a5e5..7646001324c3 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -709,11 +709,8 @@ xfs_fs_inode_init_once(
/* xfs inode */
atomic_set(&ip->i_pincount, 0);
spin_lock_init(&ip->i_flags_lock);
-
- mrlock_init(&ip->i_mmaplock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
- "xfsino", ip->i_ino);
- mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
- "xfsino", ip->i_ino);
+ init_rwsem(&ip->i_mmaplock);
+ init_rwsem(&ip->i_lock);
}
/*
--
2.25.1
