Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core locking updates from Ingo Molnar:
 "The main changes in this cycle are:

   - Another attempt at enabling cross-release lockdep dependency
     tracking (automatically part of CONFIG_PROVE_LOCKING=y), this time
     with better performance and fewer false positives. (Byungchul Park)

   - Introduce lockdep_assert_irqs_enabled()/disabled() and convert
     open-coded equivalents to lockdep variants. (Frederic Weisbecker)

   - Add down_read_killable() and use it in the VFS's iterate_dir()
     method. (Kirill Tkhai)

   - Convert remaining uses of ACCESS_ONCE() to
     READ_ONCE()/WRITE_ONCE(). Most of the conversion was Coccinelle
     driven. (Mark Rutland, Paul E. McKenney)

   - Get rid of lockless_dereference(), by strengthening Alpha atomics,
     strengthening READ_ONCE() with smp_read_barrier_depends() and thus
     being able to convert users of lockless_dereference() to
     READ_ONCE(). (Will Deacon)

   - Various micro-optimizations:

        - better PV qspinlocks (Waiman Long),
        - better x86 barriers (Michael S. Tsirkin)
        - better x86 refcounts (Kees Cook)

   - ... plus other fixes and enhancements. (Borislav Petkov, Juergen
     Gross, Miguel Bernal Marin)"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  locking/x86: Use LOCK ADD for smp_mb() instead of MFENCE
  rcu: Use lockdep to assert IRQs are disabled/enabled
  netpoll: Use lockdep to assert IRQs are disabled/enabled
  timers/posix-cpu-timers: Use lockdep to assert IRQs are disabled/enabled
  sched/clock, sched/cputime: Use lockdep to assert IRQs are disabled/enabled
  irq_work: Use lockdep to assert IRQs are disabled/enabled
  irq/timings: Use lockdep to assert IRQs are disabled/enabled
  perf/core: Use lockdep to assert IRQs are disabled/enabled
  x86: Use lockdep to assert IRQs are disabled/enabled
  smp/core: Use lockdep to assert IRQs are disabled/enabled
  timers/hrtimer: Use lockdep to assert IRQs are disabled/enabled
  timers/nohz: Use lockdep to assert IRQs are disabled/enabled
  workqueue: Use lockdep to assert IRQs are disabled/enabled
  irq/softirqs: Use lockdep to assert IRQs are disabled/enabled
  locking/lockdep: Add IRQs disabled/enabled assertion APIs: lockdep_assert_irqs_enabled()/disabled()
  locking/pvqspinlock: Implement hybrid PV queued/unfair locks
  locking/rwlocks: Fix comments
  x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized
  block, locking/lockdep: Assign a lock_class per gendisk used for wait_for_completion()
  workqueue: Remove now redundant lock acquisitions wrt. workqueue flushes
  ...

22 files changed, 45 insertions, 54 deletions

diff --git a/fs/aio.c b/fs/aio.c
index 5a2487217072..e6de7715228c 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -576,7 +576,7 @@ static int kiocb_cancel(struct aio_kiocb *kiocb)
 	 * actually has a cancel function, hence the cmpxchg()
 	 */
 
-	cancel = ACCESS_ONCE(kiocb->ki_cancel);
+	cancel = READ_ONCE(kiocb->ki_cancel);
 	do {
 		if (!cancel || cancel == KIOCB_CANCELLED)
 			return -EINVAL;
diff --git a/fs/buffer.c b/fs/buffer.c
index 170df856bdb9..32ce01f0f95f 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1692,7 +1692,8 @@ static struct buffer_head *create_page_buffers(struct page *page, struct inode *
 	BUG_ON(!PageLocked(page));
 
 	if (!page_has_buffers(page))
-		create_empty_buffers(page, 1 << ACCESS_ONCE(inode->i_blkbits), b_state);
+		create_empty_buffers(page, 1 << READ_ONCE(inode->i_blkbits),
+				     b_state);
 	return page_buffers(page);
 }
 
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
index a38630214058..577dfaf0367f 100644
--- a/fs/crypto/keyinfo.c
+++ b/fs/crypto/keyinfo.c
@@ -374,7 +374,7 @@ void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
 	struct fscrypt_info *prev;
 
 	if (ci == NULL)
-		ci = ACCESS_ONCE(inode->i_crypt_info);
+		ci = READ_ONCE(inode->i_crypt_info);
 	if (ci == NULL)
 		return;
 
diff --git a/fs/dcache.c b/fs/dcache.c
index f90141387f01..bcc9f6981569 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -231,7 +231,7 @@ static inline int dentry_cmp(const struct dentry *dentry, const unsigned char *c
 {
 	/*
 	 * Be careful about RCU walk racing with rename:
-	 * use 'lockless_dereference' to fetch the name pointer.
+	 * use 'READ_ONCE' to fetch the name pointer.
 	 *
 	 * NOTE! Even if a rename will mean that the length
 	 * was not loaded atomically, we don't care. The
@@ -245,7 +245,7 @@ static inline int dentry_cmp(const struct dentry *dentry, const unsigned char *c
 	 * early because the data cannot match (there can
 	 * be no NUL in the ct/tcount data)
 	 */
-	const unsigned char *cs = lockless_dereference(dentry->d_name.name);
+	const unsigned char *cs = READ_ONCE(dentry->d_name.name);
 
 	return dentry_string_cmp(cs, ct, tcount);
 }
@@ -630,7 +630,7 @@ static inline struct dentry *lock_parent(struct dentry *dentry)
 	rcu_read_lock();
 	spin_unlock(&dentry->d_lock);
 again:
-	parent = ACCESS_ONCE(dentry->d_parent);
+	parent = READ_ONCE(dentry->d_parent);
 	spin_lock(&parent->d_lock);
 	/*
 	 * We can't blindly lock dentry until we are sure
@@ -721,7 +721,7 @@ static inline bool fast_dput(struct dentry *dentry)
 	 * around with a zero refcount.
 	 */
 	smp_rmb();
-	d_flags = ACCESS_ONCE(dentry->d_flags);
+	d_flags = READ_ONCE(dentry->d_flags);
 	d_flags &= DCACHE_REFERENCED | DCACHE_LRU_LIST | DCACHE_DISCONNECTED;
 
 	/* Nothing to do? Dropping the reference was all we needed? */
@@ -850,11 +850,11 @@ struct dentry *dget_parent(struct dentry *dentry)
 	 * locking.
 	 */
 	rcu_read_lock();
-	ret = ACCESS_ONCE(dentry->d_parent);
+	ret = READ_ONCE(dentry->d_parent);
 	gotref = lockref_get_not_zero(&ret->d_lockref);
 	rcu_read_unlock();
 	if (likely(gotref)) {
-		if (likely(ret == ACCESS_ONCE(dentry->d_parent)))
+		if (likely(ret == READ_ONCE(dentry->d_parent)))
 			return ret;
 		dput(ret);
 	}
@@ -3040,7 +3040,7 @@ static int prepend(char **buffer, int *buflen, const char *str, int namelen)
  * @buflen: allocated length of the buffer
  * @name:   name string and length qstr structure
  *
- * With RCU path tracing, it may race with d_move(). Use ACCESS_ONCE() to
+ * With RCU path tracing, it may race with d_move(). Use READ_ONCE() to
  * make sure that either the old or the new name pointer and length are
  * fetched. However, there may be mismatch between length and pointer.
  * The length cannot be trusted, we need to copy it byte-by-byte until
@@ -3054,8 +3054,8 @@ static int prepend(char **buffer, int *buflen, const char *str, int namelen)
  */
 static int prepend_name(char **buffer, int *buflen, const struct qstr *name)
 {
-	const char *dname = ACCESS_ONCE(name->name);
-	u32 dlen = ACCESS_ONCE(name->len);
+	const char *dname = READ_ONCE(name->name);
+	u32 dlen = READ_ONCE(name->len);
 	char *p;
 
 	smp_read_barrier_depends();
@@ -3120,7 +3120,7 @@ restart:
 		struct dentry * parent;
 
 		if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) {
-			struct mount *parent = ACCESS_ONCE(mnt->mnt_parent);
+			struct mount *parent = READ_ONCE(mnt->mnt_parent);
 			/* Escaped? */
 			if (dentry != vfsmnt->mnt_root) {
 				bptr = *buffer;
@@ -3130,7 +3130,7 @@ restart:
 			}
 			/* Global root? */
 			if (mnt != parent) {
-				dentry = ACCESS_ONCE(mnt->mnt_mountpoint);
+				dentry = READ_ONCE(mnt->mnt_mountpoint);
 				mnt = parent;
 				vfsmnt = &mnt->mnt;
 				continue;
diff --git a/fs/direct-io.c b/fs/direct-io.c
index b53e66d9abd7..98fe1325da9d 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -1152,7 +1152,7 @@ do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
 		      get_block_t get_block, dio_iodone_t end_io,
 		      dio_submit_t submit_io, int flags)
 {
-	unsigned i_blkbits = ACCESS_ONCE(inode->i_blkbits);
+	unsigned i_blkbits = READ_ONCE(inode->i_blkbits);
 	unsigned blkbits = i_blkbits;
 	unsigned blocksize_mask = (1 << blkbits) - 1;
 	ssize_t retval = -EINVAL;
diff --git a/fs/exec.c b/fs/exec.c
index 3e14ba25f678..1d6243d9f2b6 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1911,7 +1911,7 @@ void set_dumpable(struct mm_struct *mm, int value)
 		return;
 
 	do {
-		old = ACCESS_ONCE(mm->flags);
+		old = READ_ONCE(mm->flags);
 		new = (old & ~MMF_DUMPABLE_MASK) | value;
 	} while (cmpxchg(&mm->flags, old, new) != old);
 }
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 8d78ffd7b399..30f47d0f74a0 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -725,7 +725,7 @@ static void send_sigio_to_task(struct task_struct *p,
 	 * F_SETSIG can change ->signum lockless in parallel, make
 	 * sure we read it once and use the same value throughout.
 	 */
-	int signum = ACCESS_ONCE(fown->signum);
+	int signum = READ_ONCE(fown->signum);
 
 	if (!sigio_perm(p, fown, signum))
 		return;
diff --git a/fs/fs_pin.c b/fs/fs_pin.c
index 0d285fd5b44a..a6497cf8ae53 100644
--- a/fs/fs_pin.c
+++ b/fs/fs_pin.c
@@ -79,7 +79,7 @@ void mnt_pin_kill(struct mount *m)
 	while (1) {
 		struct hlist_node *p;
 		rcu_read_lock();
-		p = ACCESS_ONCE(m->mnt_pins.first);
+		p = READ_ONCE(m->mnt_pins.first);
 		if (!p) {
 			rcu_read_unlock();
 			break;
@@ -93,7 +93,7 @@ void group_pin_kill(struct hlist_head *p)
 	while (1) {
 		struct hlist_node *q;
 		rcu_read_lock();
-		q = ACCESS_ONCE(p->first);
+		q = READ_ONCE(p->first);
 		if (!q) {
 			rcu_read_unlock();
 			break;
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 13c65dd2d37d..a42d89371748 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -33,7 +33,7 @@ static struct fuse_dev *fuse_get_dev(struct file *file)
 	 * Lockless access is OK, because file->private data is set
 	 * once during mount and is valid until the file is released.
 	 */
-	return ACCESS_ONCE(file->private_data);
+	return READ_ONCE(file->private_data);
 }
 
 static void fuse_request_init(struct fuse_req *req, struct page **pages,
diff --git a/fs/inode.c b/fs/inode.c
index d1e35b53bb23..fd401028a309 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2090,7 +2090,7 @@ void inode_set_flags(struct inode *inode, unsigned int flags,
 
 	WARN_ON_ONCE(flags & ~mask);
 	do {
-		old_flags = ACCESS_ONCE(inode->i_flags);
+		old_flags = READ_ONCE(inode->i_flags);
 		new_flags = (old_flags & ~mask) | flags;
 	} while (unlikely(cmpxchg(&inode->i_flags, old_flags,
 				  new_flags) != old_flags));
diff --git a/fs/namei.c b/fs/namei.c
index ed8b9488a890..5424b10cfdc4 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1210,7 +1210,7 @@ static int follow_managed(struct path *path, struct nameidata *nd)
 	/* Given that we're not holding a lock here, we retain the value in a
 	 * local variable for each dentry as we look at it so that we don't see
 	 * the components of that value change under us */
-	while (managed = ACCESS_ONCE(path->dentry->d_flags),
+	while (managed = READ_ONCE(path->dentry->d_flags),
 	       managed &= DCACHE_MANAGED_DENTRY,
 	       unlikely(managed != 0)) {
 		/* Allow the filesystem to manage the transit without i_mutex
@@ -1395,7 +1395,7 @@ int follow_down(struct path *path)
 	unsigned managed;
 	int ret;
 
-	while (managed = ACCESS_ONCE(path->dentry->d_flags),
+	while (managed = READ_ONCE(path->dentry->d_flags),
 	       unlikely(managed & DCACHE_MANAGED_DENTRY)) {
 		/* Allow the filesystem to manage the transit without i_mutex
 		 * being held.
diff --git a/fs/namespace.c b/fs/namespace.c
index d18deb4c410b..e158ec6b527b 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -353,7 +353,7 @@ int __mnt_want_write(struct vfsmount *m)
 	 * incremented count after it has set MNT_WRITE_HOLD.
 	 */
 	smp_mb();
-	while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
+	while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
 		cpu_relax();
 	/*
 	 * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will
diff --git a/fs/ncpfs/dir.c b/fs/ncpfs/dir.c
index b5ec1d980dc9..0c57c5c5d40a 100644
--- a/fs/ncpfs/dir.c
+++ b/fs/ncpfs/dir.c
@@ -120,10 +120,6 @@ static inline int ncp_case_sensitive(const struct inode *i)
 /*
  * Note: leave the hash unchanged if the directory
  * is case-sensitive.
- *
- * Accessing the parent inode can be racy under RCU pathwalking.
- * Use ACCESS_ONCE() to make sure we use _one_ particular inode,
- * the callers will handle races.
  */
 static int 
 ncp_hash_dentry(const struct dentry *dentry, struct qstr *this)
@@ -148,11 +144,6 @@ ncp_hash_dentry(const struct dentry *dentry, struct qstr *this)
 	return 0;
 }
 
-/*
- * Accessing the parent inode can be racy under RCU pathwalking.
- * Use ACCESS_ONCE() to make sure we use _one_ particular inode,
- * the callers will handle races.
- */
 static int
 ncp_compare_dentry(const struct dentry *dentry,
 		unsigned int len, const char *str, const struct qstr *name)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 5ceaeb1f6fb6..f439f1c45008 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1081,7 +1081,7 @@ static int nfs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
 	int error;
 
 	if (flags & LOOKUP_RCU) {
-		parent = ACCESS_ONCE(dentry->d_parent);
+		parent = READ_ONCE(dentry->d_parent);
 		dir = d_inode_rcu(parent);
 		if (!dir)
 			return -ECHILD;
@@ -1168,7 +1168,7 @@ out_set_verifier:
 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
  out_valid:
 	if (flags & LOOKUP_RCU) {
-		if (parent != ACCESS_ONCE(dentry->d_parent))
+		if (parent != READ_ONCE(dentry->d_parent))
 			return -ECHILD;
 	} else
 		dput(parent);
@@ -1582,7 +1582,7 @@ static int nfs4_lookup_revalidate(struct dentry *dentry, unsigned int flags)
 		struct inode *dir;
 
 		if (flags & LOOKUP_RCU) {
-			parent = ACCESS_ONCE(dentry->d_parent);
+			parent = READ_ONCE(dentry->d_parent);
 			dir = d_inode_rcu(parent);
 			if (!dir)
 				return -ECHILD;
@@ -1596,7 +1596,7 @@ static int nfs4_lookup_revalidate(struct dentry *dentry, unsigned int flags)
 			ret = -ECHILD;
 		if (!(flags & LOOKUP_RCU))
 			dput(parent);
-		else if (parent != ACCESS_ONCE(dentry->d_parent))
+		else if (parent != READ_ONCE(dentry->d_parent))
 			return -ECHILD;
 		goto out;
 	}
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index 25d9b5adcd42..36b49bd09264 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -77,5 +77,5 @@ static inline struct ovl_inode *OVL_I(struct inode *inode)
 
 static inline struct dentry *ovl_upperdentry_dereference(struct ovl_inode *oi)
 {
-	return lockless_dereference(oi->__upperdentry);
+	return READ_ONCE(oi->__upperdentry);
 }
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 698b74dd750e..c310e3ff7f3f 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -754,7 +754,7 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end,
 	if (!od->is_upper && OVL_TYPE_UPPER(ovl_path_type(dentry))) {
 		struct inode *inode = file_inode(file);
 
-		realfile = lockless_dereference(od->upperfile);
+		realfile = READ_ONCE(od->upperfile);
 		if (!realfile) {
 			struct path upperpath;
 
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 9390032a11e1..d82549e80402 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -454,7 +454,7 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
 		cutime = sig->cutime;
 		cstime = sig->cstime;
 		cgtime = sig->cgtime;
-		rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
+		rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
 
 		/* add up live thread stats at the group level */
 		if (whole) {
diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index 7626ee11b06c..7b635d173213 100644
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -28,7 +28,7 @@ static unsigned mounts_poll(struct file *file, poll_table *wait)
 
 	poll_wait(file, &p->ns->poll, wait);
 
-	event = ACCESS_ONCE(ns->event);
+	event = READ_ONCE(ns->event);
 	if (m->poll_event != event) {
 		m->poll_event = event;
 		res |= POLLERR | POLLPRI;
diff --git a/fs/readdir.c b/fs/readdir.c
index d336db65a33e..1b83b0ad183b 100644
--- a/fs/readdir.c
+++ b/fs/readdir.c
@@ -37,13 +37,12 @@ int iterate_dir(struct file *file, struct dir_context *ctx)
 	if (res)
 		goto out;
 
-	if (shared) {
-		inode_lock_shared(inode);
-	} else {
+	if (shared)
+		res = down_read_killable(&inode->i_rwsem);
+	else
 		res = down_write_killable(&inode->i_rwsem);
-		if (res)
-			goto out;
-	}
+	if (res)
+		goto out;
 
 	res = -ENOENT;
 	if (!IS_DEADDIR(inode)) {
diff --git a/fs/splice.c b/fs/splice.c
index f3084cce0ea6..39e2dc01ac12 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -253,7 +253,7 @@ EXPORT_SYMBOL(add_to_pipe);
  */
 int splice_grow_spd(const struct pipe_inode_info *pipe, struct splice_pipe_desc *spd)
 {
-	unsigned int buffers = ACCESS_ONCE(pipe->buffers);
+	unsigned int buffers = READ_ONCE(pipe->buffers);
 
 	spd->nr_pages_max = buffers;
 	if (buffers <= PIPE_DEF_BUFFERS)
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 1c713fd5b3e6..f46d133c0949 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -381,7 +381,7 @@ int handle_userfault(struct vm_fault *vmf, unsigned long reason)
 	 * in __get_user_pages if userfaultfd_release waits on the
 	 * caller of handle_userfault to release the mmap_sem.
 	 */
-	if (unlikely(ACCESS_ONCE(ctx->released))) {
+	if (unlikely(READ_ONCE(ctx->released))) {
 		/*
 		 * Don't return VM_FAULT_SIGBUS in this case, so a non
 		 * cooperative manager can close the uffd after the
@@ -477,7 +477,7 @@ int handle_userfault(struct vm_fault *vmf, unsigned long reason)
 						       vmf->flags, reason);
 	up_read(&mm->mmap_sem);
 
-	if (likely(must_wait && !ACCESS_ONCE(ctx->released) &&
+	if (likely(must_wait && !READ_ONCE(ctx->released) &&
 		   (return_to_userland ? !signal_pending(current) :
 		    !fatal_signal_pending(current)))) {
 		wake_up_poll(&ctx->fd_wqh, POLLIN);
@@ -586,7 +586,7 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
 		set_current_state(TASK_KILLABLE);
 		if (ewq->msg.event == 0)
 			break;
-		if (ACCESS_ONCE(ctx->released) ||
+		if (READ_ONCE(ctx->released) ||
 		    fatal_signal_pending(current)) {
 			/*
 			 * &ewq->wq may be queued in fork_event, but
@@ -833,7 +833,7 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
 	struct userfaultfd_wake_range range = { .len = 0, };
 	unsigned long new_flags;
 
-	ACCESS_ONCE(ctx->released) = true;
+	WRITE_ONCE(ctx->released, true);
 
 	if (!mmget_not_zero(mm))
 		goto wakeup;
diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index 51bf7b827387..129975970d99 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -592,9 +592,9 @@ xlog_valid_lsn(
 	 * a transiently forward state. Instead, we can see the LSN in a
 	 * transiently behind state if we happen to race with a cycle wrap.
 	 */
-	cur_cycle = ACCESS_ONCE(log->l_curr_cycle);
+	cur_cycle = READ_ONCE(log->l_curr_cycle);
 	smp_rmb();
-	cur_block = ACCESS_ONCE(log->l_curr_block);
+	cur_block = READ_ONCE(log->l_curr_block);
 
 	if ((CYCLE_LSN(lsn) > cur_cycle) ||
 	    (CYCLE_LSN(lsn) == cur_cycle && BLOCK_LSN(lsn) > cur_block)) {