Remove mrlock_t as it does not provide any extra value over
rw_semaphores. Make i_lock and i_mmaplock native rw_semaphores and
replace mr*() functions with native rwsem calls.
Release the lock in xfs_btree_split() just before the work-queue
executing xfs_btree_split_worker() is scheduled and make
xfs_btree_split_worker() to acquire the lock as a first thing and
release it just before returning from the function. This it done so the
ownership of the lock is transfered between kernel threads and thus
lockdep won't complain about lock being held by a different kernel
thread.
Signed-off-by: Pavel Reichl <preichl@xxxxxxxxxx>
---
fs/xfs/libxfs/xfs_btree.c | 14 +++++++
fs/xfs/mrlock.h | 78 ---------------------------------------
fs/xfs/xfs_inode.c | 36 ++++++++++--------
fs/xfs/xfs_inode.h | 4 +-
fs/xfs/xfs_iops.c | 4 +-
fs/xfs/xfs_linux.h | 2 +-
fs/xfs/xfs_super.c | 6 +--
7 files changed, 41 insertions(+), 103 deletions(-)
delete mode 100644 fs/xfs/mrlock.h
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 2d25bab68764..1d1bb8423688 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -2816,6 +2816,7 @@ xfs_btree_split_worker(
unsigned long pflags;
unsigned long new_pflags = PF_MEMALLOC_NOFS;
+ rwsem_acquire(&args->cur->bc_ino.ip->i_lock.dep_map, 0, 0, _RET_IP_);
/*
* we are in a transaction context here, but may also be doing work
* in kswapd context, and hence we may need to inherit that state
@@ -2832,6 +2833,7 @@ xfs_btree_split_worker(
complete(args->done);
current_restore_flags_nested(&pflags, new_pflags);
+ rwsem_release(&args->cur->bc_ino.ip->i_lock.dep_map, _THIS_IP_);
}
/*
@@ -2863,8 +2865,20 @@ xfs_btree_split(
args.done = &done;
args.kswapd = current_is_kswapd();
INIT_WORK_ONSTACK(&args.work, xfs_btree_split_worker);
+ /*
+ * Update lockdep's ownership information to reflect that we
+ * will be transferring the ilock from this thread to the
+ * worker.
+ */
+ rwsem_release(&cur->bc_ino.ip->i_lock.dep_map, _THIS_IP_);
queue_work(xfs_alloc_wq, &args.work);
wait_for_completion(&done);
+ /*
+ * Update lockdep's lock ownership information to point to
+ * this thread as the lock owner now that the worker item is
+ * done.
+ */
+ rwsem_acquire(&cur->bc_ino.ip->i_lock.dep_map, 0, 0, _RET_IP_);
destroy_work_on_stack(&args.work);
return args.result;
}
diff --git a/fs/xfs/mrlock.h b/fs/xfs/mrlock.h
deleted file mode 100644
index 79155eec341b..000000000000
--- a/fs/xfs/mrlock.h
+++ /dev/null
@@ -1,78 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (c) 2000-2006 Silicon Graphics, Inc.
- * All Rights Reserved.
- */
-#ifndef __XFS_SUPPORT_MRLOCK_H__
-#define __XFS_SUPPORT_MRLOCK_H__
-
-#include <linux/rwsem.h>
-
-typedef struct {
- struct rw_semaphore mr_lock;
-#if defined(DEBUG) || defined(XFS_WARN)
- int mr_writer;
-#endif
-} mrlock_t;
-
-#if defined(DEBUG) || defined(XFS_WARN)
-#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_nested(mrlock_t *mrp, int subclass)
-{
- down_read_nested(&mrp->mr_lock, subclass);
-}
-
-static inline void mrupdate_nested(mrlock_t *mrp, int subclass)
-{
- down_write_nested(&mrp->mr_lock, subclass);
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 1;
-#endif
-}
-
-static inline int mrtryaccess(mrlock_t *mrp)
-{
- return down_read_trylock(&mrp->mr_lock);
-}
-
-static inline int mrtryupdate(mrlock_t *mrp)
-{
- if (!down_write_trylock(&mrp->mr_lock))
- return 0;
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 1;
-#endif
- return 1;
-}
-
-static inline void mrunlock_excl(mrlock_t *mrp)
-{
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 0;
-#endif
- up_write(&mrp->mr_lock);
-}
-
-static inline void mrunlock_shared(mrlock_t *mrp)
-{
- up_read(&mrp->mr_lock);
-}
-
-static inline void mrdemote(mrlock_t *mrp)
-{
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 0;
-#endif
- downgrade_write(&mrp->mr_lock);
-}
-
-#endif /* __XFS_SUPPORT_MRLOCK_H__ */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 035925d406d5..213a4a947854 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -191,14 +191,15 @@ 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);
@@ -385,11 +386,14 @@ xfs_isilocked(
uint lock_flags)
{
if (lock_flags & (XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)) {
+ ASSERT(!(lock_flags & ~(XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)));
return __xfs_rwsem_islocked(&ip->i_lock,
(lock_flags >> XFS_ILOCK_FLAG_SHIFT));
}
if (lock_flags & (XFS_MMAPLOCK_EXCL | XFS_MMAPLOCK_SHARED)) {
+ ASSERT(!(lock_flags &
+ ~(XFS_MMAPLOCK_EXCL | XFS_MMAPLOCK_SHARED)));
return __xfs_rwsem_islocked(&ip->i_mmaplock,
(lock_flags >> XFS_MMAPLOCK_FLAG_SHIFT));
}
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 77d5655191ab..02c98ecfe4c5 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 */
/*
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 80a13c8561d8..66cca3e599c7 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1336,9 +1336,9 @@ xfs_setup_inode(
*/
lockdep_set_class(&inode->i_rwsem,
&inode->i_sb->s_type->i_mutex_dir_key);
- lockdep_set_class(&ip->i_lock.mr_lock, &xfs_dir_ilock_class);
+ lockdep_set_class(&ip->i_lock, &xfs_dir_ilock_class);
} else {
- lockdep_set_class(&ip->i_lock.mr_lock, &xfs_nondir_ilock_class);
+ lockdep_set_class(&ip->i_lock, &xfs_nondir_ilock_class);
}
/*
diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index ab737fed7b12..ba37217f86d2 100644
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -22,7 +22,6 @@ typedef __u32 xfs_nlink_t;
#include "xfs_types.h"
#include "kmem.h"
-#include "mrlock.h"
#include <linux/semaphore.h>
#include <linux/mm.h>
@@ -61,6 +60,7 @@ typedef __u32 xfs_nlink_t;
#include <linux/ratelimit.h>
#include <linux/rhashtable.h>
#include <linux/xattr.h>
+#include <linux/rwsem.h>
#include <asm/page.h>
#include <asm/div64.h>
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 71ac6c1cdc36..00be9cfa29fa 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -708,10 +708,8 @@ xfs_fs_inode_init_once(
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);
}
/*
--
2.26.2
