![Dave Chinner](/assets/img/avatar_default.png)
We now have two copies of AIL delete operations that are mostly duplicate functionality. The single log item deletes can be implemented via the bulk updates by turning xfs_trans_ail_delete() into a simple wrapper. This removes all the duplicate delete functionality and associated helpers. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
765 lines
20 KiB
C
765 lines
20 KiB
C
/*
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* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
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* Copyright (c) 2008 Dave Chinner
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "xfs.h"
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#include "xfs_fs.h"
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#include "xfs_types.h"
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#include "xfs_log.h"
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#include "xfs_inum.h"
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#include "xfs_trans.h"
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#include "xfs_sb.h"
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#include "xfs_ag.h"
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#include "xfs_mount.h"
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#include "xfs_trans_priv.h"
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#include "xfs_error.h"
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STATIC void xfs_ail_splice(struct xfs_ail *, struct list_head *, xfs_lsn_t);
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STATIC void xfs_ail_delete(struct xfs_ail *, xfs_log_item_t *);
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STATIC xfs_log_item_t * xfs_ail_min(struct xfs_ail *);
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STATIC xfs_log_item_t * xfs_ail_next(struct xfs_ail *, xfs_log_item_t *);
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#ifdef DEBUG
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STATIC void xfs_ail_check(struct xfs_ail *, xfs_log_item_t *);
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#else
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#define xfs_ail_check(a,l)
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#endif /* DEBUG */
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/*
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* This is called by the log manager code to determine the LSN
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* of the tail of the log. This is exactly the LSN of the first
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* item in the AIL. If the AIL is empty, then this function
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* returns 0.
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*
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* We need the AIL lock in order to get a coherent read of the
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* lsn of the last item in the AIL.
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*/
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xfs_lsn_t
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xfs_trans_ail_tail(
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struct xfs_ail *ailp)
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{
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xfs_lsn_t lsn;
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xfs_log_item_t *lip;
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spin_lock(&ailp->xa_lock);
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lip = xfs_ail_min(ailp);
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if (lip == NULL) {
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lsn = (xfs_lsn_t)0;
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} else {
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lsn = lip->li_lsn;
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}
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spin_unlock(&ailp->xa_lock);
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return lsn;
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}
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/*
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* xfs_trans_push_ail
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*
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* This routine is called to move the tail of the AIL forward. It does this by
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* trying to flush items in the AIL whose lsns are below the given
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* threshold_lsn.
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*
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* the push is run asynchronously in a separate thread, so we return the tail
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* of the log right now instead of the tail after the push. This means we will
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* either continue right away, or we will sleep waiting on the async thread to
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* do its work.
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*
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* We do this unlocked - we only need to know whether there is anything in the
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* AIL at the time we are called. We don't need to access the contents of
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* any of the objects, so the lock is not needed.
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*/
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void
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xfs_trans_ail_push(
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struct xfs_ail *ailp,
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xfs_lsn_t threshold_lsn)
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{
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xfs_log_item_t *lip;
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lip = xfs_ail_min(ailp);
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if (lip && !XFS_FORCED_SHUTDOWN(ailp->xa_mount)) {
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if (XFS_LSN_CMP(threshold_lsn, ailp->xa_target) > 0)
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xfsaild_wakeup(ailp, threshold_lsn);
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}
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}
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/*
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* AIL traversal cursor initialisation.
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*
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* The cursor keeps track of where our current traversal is up
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* to by tracking the next ƣtem in the list for us. However, for
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* this to be safe, removing an object from the AIL needs to invalidate
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* any cursor that points to it. hence the traversal cursor needs to
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* be linked to the struct xfs_ail so that deletion can search all the
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* active cursors for invalidation.
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*
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* We don't link the push cursor because it is embedded in the struct
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* xfs_ail and hence easily findable.
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*/
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STATIC void
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xfs_trans_ail_cursor_init(
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struct xfs_ail *ailp,
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struct xfs_ail_cursor *cur)
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{
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cur->item = NULL;
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if (cur == &ailp->xa_cursors)
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return;
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cur->next = ailp->xa_cursors.next;
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ailp->xa_cursors.next = cur;
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}
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/*
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* Set the cursor to the next item, because when we look
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* up the cursor the current item may have been freed.
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*/
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STATIC void
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xfs_trans_ail_cursor_set(
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struct xfs_ail *ailp,
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struct xfs_ail_cursor *cur,
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struct xfs_log_item *lip)
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{
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if (lip)
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cur->item = xfs_ail_next(ailp, lip);
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}
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/*
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* Get the next item in the traversal and advance the cursor.
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* If the cursor was invalidated (inidicated by a lip of 1),
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* restart the traversal.
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*/
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struct xfs_log_item *
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xfs_trans_ail_cursor_next(
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struct xfs_ail *ailp,
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struct xfs_ail_cursor *cur)
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{
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struct xfs_log_item *lip = cur->item;
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if ((__psint_t)lip & 1)
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lip = xfs_ail_min(ailp);
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xfs_trans_ail_cursor_set(ailp, cur, lip);
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return lip;
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}
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/*
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* Now that the traversal is complete, we need to remove the cursor
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* from the list of traversing cursors. Avoid removing the embedded
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* push cursor, but use the fact it is always present to make the
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* list deletion simple.
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*/
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void
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xfs_trans_ail_cursor_done(
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struct xfs_ail *ailp,
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struct xfs_ail_cursor *done)
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{
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struct xfs_ail_cursor *prev = NULL;
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struct xfs_ail_cursor *cur;
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done->item = NULL;
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if (done == &ailp->xa_cursors)
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return;
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prev = &ailp->xa_cursors;
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for (cur = prev->next; cur; prev = cur, cur = prev->next) {
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if (cur == done) {
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prev->next = cur->next;
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break;
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}
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}
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ASSERT(cur);
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}
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/*
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* Invalidate any cursor that is pointing to this item. This is
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* called when an item is removed from the AIL. Any cursor pointing
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* to this object is now invalid and the traversal needs to be
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* terminated so it doesn't reference a freed object. We set the
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* cursor item to a value of 1 so we can distinguish between an
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* invalidation and the end of the list when getting the next item
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* from the cursor.
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*/
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STATIC void
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xfs_trans_ail_cursor_clear(
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struct xfs_ail *ailp,
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struct xfs_log_item *lip)
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{
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struct xfs_ail_cursor *cur;
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/* need to search all cursors */
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for (cur = &ailp->xa_cursors; cur; cur = cur->next) {
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if (cur->item == lip)
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cur->item = (struct xfs_log_item *)
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((__psint_t)cur->item | 1);
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}
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}
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/*
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* Return the item in the AIL with the current lsn.
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* Return the current tree generation number for use
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* in calls to xfs_trans_next_ail().
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*/
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xfs_log_item_t *
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xfs_trans_ail_cursor_first(
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struct xfs_ail *ailp,
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struct xfs_ail_cursor *cur,
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xfs_lsn_t lsn)
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{
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xfs_log_item_t *lip;
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xfs_trans_ail_cursor_init(ailp, cur);
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lip = xfs_ail_min(ailp);
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if (lsn == 0)
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goto out;
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list_for_each_entry(lip, &ailp->xa_ail, li_ail) {
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if (XFS_LSN_CMP(lip->li_lsn, lsn) >= 0)
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goto out;
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}
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lip = NULL;
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out:
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xfs_trans_ail_cursor_set(ailp, cur, lip);
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return lip;
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}
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/*
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* xfsaild_push does the work of pushing on the AIL. Returning a timeout of
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* zero indicates that the caller should sleep until woken.
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*/
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long
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xfsaild_push(
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struct xfs_ail *ailp,
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xfs_lsn_t *last_lsn)
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{
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long tout = 0;
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xfs_lsn_t last_pushed_lsn = *last_lsn;
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xfs_lsn_t target = ailp->xa_target;
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xfs_lsn_t lsn;
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xfs_log_item_t *lip;
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int flush_log, count, stuck;
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xfs_mount_t *mp = ailp->xa_mount;
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struct xfs_ail_cursor *cur = &ailp->xa_cursors;
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int push_xfsbufd = 0;
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spin_lock(&ailp->xa_lock);
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xfs_trans_ail_cursor_init(ailp, cur);
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lip = xfs_trans_ail_cursor_first(ailp, cur, *last_lsn);
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if (!lip || XFS_FORCED_SHUTDOWN(mp)) {
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/*
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* AIL is empty or our push has reached the end.
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*/
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xfs_trans_ail_cursor_done(ailp, cur);
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spin_unlock(&ailp->xa_lock);
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*last_lsn = 0;
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return tout;
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}
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XFS_STATS_INC(xs_push_ail);
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/*
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* While the item we are looking at is below the given threshold
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* try to flush it out. We'd like not to stop until we've at least
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* tried to push on everything in the AIL with an LSN less than
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* the given threshold.
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*
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* However, we will stop after a certain number of pushes and wait
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* for a reduced timeout to fire before pushing further. This
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* prevents use from spinning when we can't do anything or there is
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* lots of contention on the AIL lists.
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*/
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lsn = lip->li_lsn;
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flush_log = stuck = count = 0;
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while ((XFS_LSN_CMP(lip->li_lsn, target) < 0)) {
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int lock_result;
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/*
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* If we can lock the item without sleeping, unlock the AIL
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* lock and flush the item. Then re-grab the AIL lock so we
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* can look for the next item on the AIL. List changes are
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* handled by the AIL lookup functions internally
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*
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* If we can't lock the item, either its holder will flush it
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* or it is already being flushed or it is being relogged. In
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* any of these case it is being taken care of and we can just
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* skip to the next item in the list.
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*/
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lock_result = IOP_TRYLOCK(lip);
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spin_unlock(&ailp->xa_lock);
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switch (lock_result) {
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case XFS_ITEM_SUCCESS:
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XFS_STATS_INC(xs_push_ail_success);
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IOP_PUSH(lip);
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last_pushed_lsn = lsn;
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break;
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case XFS_ITEM_PUSHBUF:
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XFS_STATS_INC(xs_push_ail_pushbuf);
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IOP_PUSHBUF(lip);
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last_pushed_lsn = lsn;
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push_xfsbufd = 1;
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break;
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case XFS_ITEM_PINNED:
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XFS_STATS_INC(xs_push_ail_pinned);
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stuck++;
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flush_log = 1;
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break;
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case XFS_ITEM_LOCKED:
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XFS_STATS_INC(xs_push_ail_locked);
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last_pushed_lsn = lsn;
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stuck++;
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break;
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default:
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ASSERT(0);
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break;
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}
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spin_lock(&ailp->xa_lock);
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/* should we bother continuing? */
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if (XFS_FORCED_SHUTDOWN(mp))
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break;
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ASSERT(mp->m_log);
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count++;
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/*
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* Are there too many items we can't do anything with?
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* If we we are skipping too many items because we can't flush
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* them or they are already being flushed, we back off and
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* given them time to complete whatever operation is being
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* done. i.e. remove pressure from the AIL while we can't make
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* progress so traversals don't slow down further inserts and
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* removals to/from the AIL.
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*
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* The value of 100 is an arbitrary magic number based on
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* observation.
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*/
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if (stuck > 100)
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break;
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lip = xfs_trans_ail_cursor_next(ailp, cur);
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if (lip == NULL)
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break;
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lsn = lip->li_lsn;
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}
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xfs_trans_ail_cursor_done(ailp, cur);
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spin_unlock(&ailp->xa_lock);
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if (flush_log) {
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/*
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* If something we need to push out was pinned, then
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* push out the log so it will become unpinned and
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* move forward in the AIL.
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*/
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XFS_STATS_INC(xs_push_ail_flush);
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xfs_log_force(mp, 0);
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}
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if (push_xfsbufd) {
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/* we've got delayed write buffers to flush */
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wake_up_process(mp->m_ddev_targp->bt_task);
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}
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if (!count) {
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/* We're past our target or empty, so idle */
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last_pushed_lsn = 0;
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} else if (XFS_LSN_CMP(lsn, target) >= 0) {
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/*
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* We reached the target so wait a bit longer for I/O to
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* complete and remove pushed items from the AIL before we
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* start the next scan from the start of the AIL.
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*/
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tout = 50;
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last_pushed_lsn = 0;
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} else if ((stuck * 100) / count > 90) {
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/*
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* Either there is a lot of contention on the AIL or we
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* are stuck due to operations in progress. "Stuck" in this
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* case is defined as >90% of the items we tried to push
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* were stuck.
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*
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* Backoff a bit more to allow some I/O to complete before
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* continuing from where we were.
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*/
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tout = 20;
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} else {
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/* more to do, but wait a short while before continuing */
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tout = 10;
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}
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*last_lsn = last_pushed_lsn;
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return tout;
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}
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/*
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* This is to be called when an item is unlocked that may have
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* been in the AIL. It will wake up the first member of the AIL
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* wait list if this item's unlocking might allow it to progress.
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* If the item is in the AIL, then we need to get the AIL lock
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* while doing our checking so we don't race with someone going
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* to sleep waiting for this event in xfs_trans_push_ail().
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*/
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void
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xfs_trans_unlocked_item(
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struct xfs_ail *ailp,
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xfs_log_item_t *lip)
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{
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xfs_log_item_t *min_lip;
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/*
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* If we're forcibly shutting down, we may have
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* unlocked log items arbitrarily. The last thing
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* we want to do is to move the tail of the log
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* over some potentially valid data.
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*/
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if (!(lip->li_flags & XFS_LI_IN_AIL) ||
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XFS_FORCED_SHUTDOWN(ailp->xa_mount)) {
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return;
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}
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/*
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* This is the one case where we can call into xfs_ail_min()
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* without holding the AIL lock because we only care about the
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* case where we are at the tail of the AIL. If the object isn't
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* at the tail, it doesn't matter what result we get back. This
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* is slightly racy because since we were just unlocked, we could
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* go to sleep between the call to xfs_ail_min and the call to
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* xfs_log_move_tail, have someone else lock us, commit to us disk,
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* move us out of the tail of the AIL, and then we wake up. However,
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* the call to xfs_log_move_tail() doesn't do anything if there's
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* not enough free space to wake people up so we're safe calling it.
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*/
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min_lip = xfs_ail_min(ailp);
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if (min_lip == lip)
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xfs_log_move_tail(ailp->xa_mount, 1);
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} /* xfs_trans_unlocked_item */
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/*
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* xfs_trans_ail_update - bulk AIL insertion operation.
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*
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* @xfs_trans_ail_update takes an array of log items that all need to be
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* positioned at the same LSN in the AIL. If an item is not in the AIL, it will
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* be added. Otherwise, it will be repositioned by removing it and re-adding
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* it to the AIL. If we move the first item in the AIL, update the log tail to
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* match the new minimum LSN in the AIL.
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*
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* This function takes the AIL lock once to execute the update operations on
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* all the items in the array, and as such should not be called with the AIL
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* lock held. As a result, once we have the AIL lock, we need to check each log
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* item LSN to confirm it needs to be moved forward in the AIL.
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*
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* To optimise the insert operation, we delete all the items from the AIL in
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* the first pass, moving them into a temporary list, then splice the temporary
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* list into the correct position in the AIL. This avoids needing to do an
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* insert operation on every item.
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*
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* This function must be called with the AIL lock held. The lock is dropped
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* before returning.
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*/
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void
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xfs_trans_ail_update_bulk(
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struct xfs_ail *ailp,
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struct xfs_log_item **log_items,
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int nr_items,
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xfs_lsn_t lsn) __releases(ailp->xa_lock)
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{
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xfs_log_item_t *mlip;
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xfs_lsn_t tail_lsn;
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int mlip_changed = 0;
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int i;
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LIST_HEAD(tmp);
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mlip = xfs_ail_min(ailp);
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for (i = 0; i < nr_items; i++) {
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struct xfs_log_item *lip = log_items[i];
|
|
if (lip->li_flags & XFS_LI_IN_AIL) {
|
|
/* check if we really need to move the item */
|
|
if (XFS_LSN_CMP(lsn, lip->li_lsn) <= 0)
|
|
continue;
|
|
|
|
xfs_ail_delete(ailp, lip);
|
|
if (mlip == lip)
|
|
mlip_changed = 1;
|
|
} else {
|
|
lip->li_flags |= XFS_LI_IN_AIL;
|
|
}
|
|
lip->li_lsn = lsn;
|
|
list_add(&lip->li_ail, &tmp);
|
|
}
|
|
|
|
xfs_ail_splice(ailp, &tmp, lsn);
|
|
|
|
if (!mlip_changed) {
|
|
spin_unlock(&ailp->xa_lock);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* It is not safe to access mlip after the AIL lock is dropped, so we
|
|
* must get a copy of li_lsn before we do so. This is especially
|
|
* important on 32-bit platforms where accessing and updating 64-bit
|
|
* values like li_lsn is not atomic.
|
|
*/
|
|
mlip = xfs_ail_min(ailp);
|
|
tail_lsn = mlip->li_lsn;
|
|
spin_unlock(&ailp->xa_lock);
|
|
xfs_log_move_tail(ailp->xa_mount, tail_lsn);
|
|
}
|
|
|
|
/*
|
|
* xfs_trans_ail_delete_bulk - remove multiple log items from the AIL
|
|
*
|
|
* @xfs_trans_ail_delete_bulk takes an array of log items that all need to
|
|
* removed from the AIL. The caller is already holding the AIL lock, and done
|
|
* all the checks necessary to ensure the items passed in via @log_items are
|
|
* ready for deletion. This includes checking that the items are in the AIL.
|
|
*
|
|
* For each log item to be removed, unlink it from the AIL, clear the IN_AIL
|
|
* flag from the item and reset the item's lsn to 0. If we remove the first
|
|
* item in the AIL, update the log tail to match the new minimum LSN in the
|
|
* AIL.
|
|
*
|
|
* This function will not drop the AIL lock until all items are removed from
|
|
* the AIL to minimise the amount of lock traffic on the AIL. This does not
|
|
* greatly increase the AIL hold time, but does significantly reduce the amount
|
|
* of traffic on the lock, especially during IO completion.
|
|
*
|
|
* This function must be called with the AIL lock held. The lock is dropped
|
|
* before returning.
|
|
*/
|
|
void
|
|
xfs_trans_ail_delete_bulk(
|
|
struct xfs_ail *ailp,
|
|
struct xfs_log_item **log_items,
|
|
int nr_items) __releases(ailp->xa_lock)
|
|
{
|
|
xfs_log_item_t *mlip;
|
|
xfs_lsn_t tail_lsn;
|
|
int mlip_changed = 0;
|
|
int i;
|
|
|
|
mlip = xfs_ail_min(ailp);
|
|
|
|
for (i = 0; i < nr_items; i++) {
|
|
struct xfs_log_item *lip = log_items[i];
|
|
if (!(lip->li_flags & XFS_LI_IN_AIL)) {
|
|
struct xfs_mount *mp = ailp->xa_mount;
|
|
|
|
spin_unlock(&ailp->xa_lock);
|
|
if (!XFS_FORCED_SHUTDOWN(mp)) {
|
|
xfs_cmn_err(XFS_PTAG_AILDELETE, CE_ALERT, mp,
|
|
"%s: attempting to delete a log item that is not in the AIL",
|
|
__func__);
|
|
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
|
|
}
|
|
return;
|
|
}
|
|
|
|
xfs_ail_delete(ailp, lip);
|
|
lip->li_flags &= ~XFS_LI_IN_AIL;
|
|
lip->li_lsn = 0;
|
|
if (mlip == lip)
|
|
mlip_changed = 1;
|
|
}
|
|
|
|
if (!mlip_changed) {
|
|
spin_unlock(&ailp->xa_lock);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* It is not safe to access mlip after the AIL lock is dropped, so we
|
|
* must get a copy of li_lsn before we do so. This is especially
|
|
* important on 32-bit platforms where accessing and updating 64-bit
|
|
* values like li_lsn is not atomic. It is possible we've emptied the
|
|
* AIL here, so if that is the case, pass an LSN of 0 to the tail move.
|
|
*/
|
|
mlip = xfs_ail_min(ailp);
|
|
tail_lsn = mlip ? mlip->li_lsn : 0;
|
|
spin_unlock(&ailp->xa_lock);
|
|
xfs_log_move_tail(ailp->xa_mount, tail_lsn);
|
|
}
|
|
|
|
/*
|
|
* The active item list (AIL) is a doubly linked list of log
|
|
* items sorted by ascending lsn. The base of the list is
|
|
* a forw/back pointer pair embedded in the xfs mount structure.
|
|
* The base is initialized with both pointers pointing to the
|
|
* base. This case always needs to be distinguished, because
|
|
* the base has no lsn to look at. We almost always insert
|
|
* at the end of the list, so on inserts we search from the
|
|
* end of the list to find where the new item belongs.
|
|
*/
|
|
|
|
/*
|
|
* Initialize the doubly linked list to point only to itself.
|
|
*/
|
|
int
|
|
xfs_trans_ail_init(
|
|
xfs_mount_t *mp)
|
|
{
|
|
struct xfs_ail *ailp;
|
|
int error;
|
|
|
|
ailp = kmem_zalloc(sizeof(struct xfs_ail), KM_MAYFAIL);
|
|
if (!ailp)
|
|
return ENOMEM;
|
|
|
|
ailp->xa_mount = mp;
|
|
INIT_LIST_HEAD(&ailp->xa_ail);
|
|
spin_lock_init(&ailp->xa_lock);
|
|
error = xfsaild_start(ailp);
|
|
if (error)
|
|
goto out_free_ailp;
|
|
mp->m_ail = ailp;
|
|
return 0;
|
|
|
|
out_free_ailp:
|
|
kmem_free(ailp);
|
|
return error;
|
|
}
|
|
|
|
void
|
|
xfs_trans_ail_destroy(
|
|
xfs_mount_t *mp)
|
|
{
|
|
struct xfs_ail *ailp = mp->m_ail;
|
|
|
|
xfsaild_stop(ailp);
|
|
kmem_free(ailp);
|
|
}
|
|
|
|
/*
|
|
* splice the log item list into the AIL at the given LSN.
|
|
*/
|
|
STATIC void
|
|
xfs_ail_splice(
|
|
struct xfs_ail *ailp,
|
|
struct list_head *list,
|
|
xfs_lsn_t lsn)
|
|
{
|
|
xfs_log_item_t *next_lip;
|
|
|
|
/*
|
|
* If the list is empty, just insert the item.
|
|
*/
|
|
if (list_empty(&ailp->xa_ail)) {
|
|
list_splice(list, &ailp->xa_ail);
|
|
return;
|
|
}
|
|
|
|
list_for_each_entry_reverse(next_lip, &ailp->xa_ail, li_ail) {
|
|
if (XFS_LSN_CMP(next_lip->li_lsn, lsn) <= 0)
|
|
break;
|
|
}
|
|
|
|
ASSERT((&next_lip->li_ail == &ailp->xa_ail) ||
|
|
(XFS_LSN_CMP(next_lip->li_lsn, lsn) <= 0));
|
|
|
|
list_splice_init(list, &next_lip->li_ail);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Delete the given item from the AIL. Return a pointer to the item.
|
|
*/
|
|
STATIC void
|
|
xfs_ail_delete(
|
|
struct xfs_ail *ailp,
|
|
xfs_log_item_t *lip)
|
|
{
|
|
xfs_ail_check(ailp, lip);
|
|
list_del(&lip->li_ail);
|
|
xfs_trans_ail_cursor_clear(ailp, lip);
|
|
}
|
|
|
|
/*
|
|
* Return a pointer to the first item in the AIL.
|
|
* If the AIL is empty, then return NULL.
|
|
*/
|
|
STATIC xfs_log_item_t *
|
|
xfs_ail_min(
|
|
struct xfs_ail *ailp)
|
|
{
|
|
if (list_empty(&ailp->xa_ail))
|
|
return NULL;
|
|
|
|
return list_first_entry(&ailp->xa_ail, xfs_log_item_t, li_ail);
|
|
}
|
|
|
|
/*
|
|
* Return a pointer to the item which follows
|
|
* the given item in the AIL. If the given item
|
|
* is the last item in the list, then return NULL.
|
|
*/
|
|
STATIC xfs_log_item_t *
|
|
xfs_ail_next(
|
|
struct xfs_ail *ailp,
|
|
xfs_log_item_t *lip)
|
|
{
|
|
if (lip->li_ail.next == &ailp->xa_ail)
|
|
return NULL;
|
|
|
|
return list_first_entry(&lip->li_ail, xfs_log_item_t, li_ail);
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
/*
|
|
* Check that the list is sorted as it should be.
|
|
*/
|
|
STATIC void
|
|
xfs_ail_check(
|
|
struct xfs_ail *ailp,
|
|
xfs_log_item_t *lip)
|
|
{
|
|
xfs_log_item_t *prev_lip;
|
|
|
|
if (list_empty(&ailp->xa_ail))
|
|
return;
|
|
|
|
/*
|
|
* Check the next and previous entries are valid.
|
|
*/
|
|
ASSERT((lip->li_flags & XFS_LI_IN_AIL) != 0);
|
|
prev_lip = list_entry(lip->li_ail.prev, xfs_log_item_t, li_ail);
|
|
if (&prev_lip->li_ail != &ailp->xa_ail)
|
|
ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) <= 0);
|
|
|
|
prev_lip = list_entry(lip->li_ail.next, xfs_log_item_t, li_ail);
|
|
if (&prev_lip->li_ail != &ailp->xa_ail)
|
|
ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) >= 0);
|
|
|
|
|
|
#ifdef XFS_TRANS_DEBUG
|
|
/*
|
|
* Walk the list checking lsn ordering, and that every entry has the
|
|
* XFS_LI_IN_AIL flag set. This is really expensive, so only do it
|
|
* when specifically debugging the transaction subsystem.
|
|
*/
|
|
prev_lip = list_entry(&ailp->xa_ail, xfs_log_item_t, li_ail);
|
|
list_for_each_entry(lip, &ailp->xa_ail, li_ail) {
|
|
if (&prev_lip->li_ail != &ailp->xa_ail)
|
|
ASSERT(XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) <= 0);
|
|
ASSERT((lip->li_flags & XFS_LI_IN_AIL) != 0);
|
|
prev_lip = lip;
|
|
}
|
|
#endif /* XFS_TRANS_DEBUG */
|
|
}
|
|
#endif /* DEBUG */
|