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Diffstat (limited to 'fs/xfs/xfs_trans_priv.h')
-rw-r--r--fs/xfs/xfs_trans_priv.h98
1 files changed, 83 insertions, 15 deletions
diff --git a/fs/xfs/xfs_trans_priv.h b/fs/xfs/xfs_trans_priv.h
index 3c748c4..73e2ad3 100644
--- a/fs/xfs/xfs_trans_priv.h
+++ b/fs/xfs/xfs_trans_priv.h
@@ -44,25 +44,93 @@ xfs_log_busy_slot_t *xfs_trans_add_busy(xfs_trans_t *tp,
xfs_extlen_t idx);
/*
- * From xfs_trans_ail.c
+ * AIL traversal cursor.
+ *
+ * Rather than using a generation number for detecting changes in the ail, use
+ * a cursor that is protected by the ail lock. The aild cursor exists in the
+ * struct xfs_ail, but other traversals can declare it on the stack and link it
+ * to the ail list.
+ *
+ * When an object is deleted from or moved int the AIL, the cursor list is
+ * searched to see if the object is a designated cursor item. If it is, it is
+ * deleted from the cursor so that the next time the cursor is used traversal
+ * will return to the start.
+ *
+ * This means a traversal colliding with a removal will cause a restart of the
+ * list scan, rather than any insertion or deletion anywhere in the list. The
+ * low bit of the item pointer is set if the cursor has been invalidated so
+ * that we can tell the difference between invalidation and reaching the end
+ * of the list to trigger traversal restarts.
*/
-void xfs_trans_update_ail(struct xfs_mount *mp,
- struct xfs_log_item *lip, xfs_lsn_t lsn)
- __releases(mp->m_ail_lock);
-void xfs_trans_delete_ail(struct xfs_mount *mp,
- struct xfs_log_item *lip)
- __releases(mp->m_ail_lock);
-struct xfs_log_item *xfs_trans_first_ail(struct xfs_mount *, int *);
-struct xfs_log_item *xfs_trans_next_ail(struct xfs_mount *,
- struct xfs_log_item *, int *, int *);
+struct xfs_ail_cursor {
+ struct xfs_ail_cursor *next;
+ struct xfs_log_item *item;
+};
+/*
+ * Private AIL structures.
+ *
+ * Eventually we need to drive the locking in here as well.
+ */
+struct xfs_ail {
+ struct xfs_mount *xa_mount;
+ struct list_head xa_ail;
+ uint xa_gen;
+ struct task_struct *xa_task;
+ xfs_lsn_t xa_target;
+ struct xfs_ail_cursor xa_cursors;
+ spinlock_t xa_lock;
+};
/*
- * AIL push thread support
+ * From xfs_trans_ail.c
*/
-long xfsaild_push(struct xfs_mount *, xfs_lsn_t *);
-void xfsaild_wakeup(struct xfs_mount *, xfs_lsn_t);
-int xfsaild_start(struct xfs_mount *);
-void xfsaild_stop(struct xfs_mount *);
+void xfs_trans_ail_update(struct xfs_ail *ailp,
+ struct xfs_log_item *lip, xfs_lsn_t lsn)
+ __releases(ailp->xa_lock);
+void xfs_trans_ail_delete(struct xfs_ail *ailp,
+ struct xfs_log_item *lip)
+ __releases(ailp->xa_lock);
+void xfs_trans_ail_push(struct xfs_ail *, xfs_lsn_t);
+void xfs_trans_unlocked_item(struct xfs_ail *,
+ xfs_log_item_t *);
+
+xfs_lsn_t xfs_trans_ail_tail(struct xfs_ail *ailp);
+
+struct xfs_log_item *xfs_trans_ail_cursor_first(struct xfs_ail *ailp,
+ struct xfs_ail_cursor *cur,
+ xfs_lsn_t lsn);
+struct xfs_log_item *xfs_trans_ail_cursor_next(struct xfs_ail *ailp,
+ struct xfs_ail_cursor *cur);
+void xfs_trans_ail_cursor_done(struct xfs_ail *ailp,
+ struct xfs_ail_cursor *cur);
+
+long xfsaild_push(struct xfs_ail *, xfs_lsn_t *);
+void xfsaild_wakeup(struct xfs_ail *, xfs_lsn_t);
+int xfsaild_start(struct xfs_ail *);
+void xfsaild_stop(struct xfs_ail *);
+#if BITS_PER_LONG != 64
+static inline void
+xfs_trans_ail_copy_lsn(
+ struct xfs_ail *ailp,
+ xfs_lsn_t *dst,
+ xfs_lsn_t *src)
+{
+ ASSERT(sizeof(xfs_lsn_t) == 8); /* don't lock if it shrinks */
+ spin_lock(&ailp->xa_lock);
+ *dst = *src;
+ spin_unlock(&ailp->xa_lock);
+}
+#else
+static inline void
+xfs_trans_ail_copy_lsn(
+ struct xfs_ail *ailp,
+ xfs_lsn_t *dst,
+ xfs_lsn_t *src)
+{
+ ASSERT(sizeof(xfs_lsn_t) == 8);
+ *dst = *src;
+}
+#endif
#endif /* __XFS_TRANS_PRIV_H__ */
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