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86a3717413
During recovery, every intent that we recover from the log has to be added to the AIL. Replace the open-coded addition with a helper. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
920 lines
24 KiB
C
920 lines
24 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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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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#include "xfs.h"
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#include "xfs_fs.h"
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#include "xfs_shared.h"
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#include "xfs_format.h"
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#include "xfs_log_format.h"
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#include "xfs_trans_resv.h"
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#include "xfs_mount.h"
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#include "xfs_trans.h"
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#include "xfs_trans_priv.h"
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#include "xfs_trace.h"
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#include "xfs_errortag.h"
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#include "xfs_error.h"
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#include "xfs_log.h"
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#ifdef DEBUG
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/*
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* Check that the list is sorted as it should be.
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*
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* Called with the ail lock held, but we don't want to assert fail with it
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* held otherwise we'll lock everything up and won't be able to debug the
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* cause. Hence we sample and check the state under the AIL lock and return if
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* everything is fine, otherwise we drop the lock and run the ASSERT checks.
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* Asserts may not be fatal, so pick the lock back up and continue onwards.
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*/
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STATIC void
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xfs_ail_check(
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struct xfs_ail *ailp,
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struct xfs_log_item *lip)
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__must_hold(&ailp->ail_lock)
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{
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struct xfs_log_item *prev_lip;
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struct xfs_log_item *next_lip;
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xfs_lsn_t prev_lsn = NULLCOMMITLSN;
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xfs_lsn_t next_lsn = NULLCOMMITLSN;
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xfs_lsn_t lsn;
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bool in_ail;
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if (list_empty(&ailp->ail_head))
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return;
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/*
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* Sample then check the next and previous entries are valid.
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*/
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in_ail = test_bit(XFS_LI_IN_AIL, &lip->li_flags);
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prev_lip = list_entry(lip->li_ail.prev, struct xfs_log_item, li_ail);
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if (&prev_lip->li_ail != &ailp->ail_head)
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prev_lsn = prev_lip->li_lsn;
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next_lip = list_entry(lip->li_ail.next, struct xfs_log_item, li_ail);
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if (&next_lip->li_ail != &ailp->ail_head)
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next_lsn = next_lip->li_lsn;
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lsn = lip->li_lsn;
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if (in_ail &&
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(prev_lsn == NULLCOMMITLSN || XFS_LSN_CMP(prev_lsn, lsn) <= 0) &&
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(next_lsn == NULLCOMMITLSN || XFS_LSN_CMP(next_lsn, lsn) >= 0))
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return;
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spin_unlock(&ailp->ail_lock);
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ASSERT(in_ail);
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ASSERT(prev_lsn == NULLCOMMITLSN || XFS_LSN_CMP(prev_lsn, lsn) <= 0);
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ASSERT(next_lsn == NULLCOMMITLSN || XFS_LSN_CMP(next_lsn, lsn) >= 0);
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spin_lock(&ailp->ail_lock);
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}
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#else /* !DEBUG */
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#define xfs_ail_check(a,l)
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#endif /* DEBUG */
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/*
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* Return a pointer to the last item in the AIL. If the AIL is empty, then
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* return NULL.
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*/
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static struct xfs_log_item *
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xfs_ail_max(
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struct xfs_ail *ailp)
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{
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if (list_empty(&ailp->ail_head))
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return NULL;
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return list_entry(ailp->ail_head.prev, struct xfs_log_item, li_ail);
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}
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/*
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* Return a pointer to the item which follows the given item in the AIL. If
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* the given item is the last item in the list, then return NULL.
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*/
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static struct xfs_log_item *
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xfs_ail_next(
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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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if (lip->li_ail.next == &ailp->ail_head)
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return NULL;
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return list_first_entry(&lip->li_ail, struct xfs_log_item, li_ail);
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}
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/*
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* This is called by the log manager code to determine the LSN of the tail of
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* the log. This is exactly the LSN of the first item in the AIL. If the AIL
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* is empty, then this function returns 0.
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*
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* We need the AIL lock in order to get a coherent read of the lsn of the last
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* item in the AIL.
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*/
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static xfs_lsn_t
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__xfs_ail_min_lsn(
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struct xfs_ail *ailp)
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{
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struct xfs_log_item *lip = xfs_ail_min(ailp);
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if (lip)
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return lip->li_lsn;
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return 0;
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}
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xfs_lsn_t
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xfs_ail_min_lsn(
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struct xfs_ail *ailp)
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{
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xfs_lsn_t lsn;
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spin_lock(&ailp->ail_lock);
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lsn = __xfs_ail_min_lsn(ailp);
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spin_unlock(&ailp->ail_lock);
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return lsn;
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}
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/*
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* Return the maximum lsn held in the AIL, or zero if the AIL is empty.
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*/
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static xfs_lsn_t
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xfs_ail_max_lsn(
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struct xfs_ail *ailp)
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{
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xfs_lsn_t lsn = 0;
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struct xfs_log_item *lip;
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spin_lock(&ailp->ail_lock);
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lip = xfs_ail_max(ailp);
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if (lip)
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lsn = lip->li_lsn;
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spin_unlock(&ailp->ail_lock);
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return lsn;
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}
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/*
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* The cursor keeps track of where our current traversal is up to by tracking
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* the next item in the list for us. However, for this to be safe, removing an
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* object from the AIL needs to invalidate any cursor that points to it. hence
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* the traversal cursor needs to be linked to the struct xfs_ail so that
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* deletion can search all the active cursors for invalidation.
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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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list_add_tail(&cur->list, &ailp->ail_cursors);
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}
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/*
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* Get the next item in the traversal and advance the cursor. If the cursor
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* was invalidated (indicated by a lip of 1), 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 ((uintptr_t)lip & 1)
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lip = xfs_ail_min(ailp);
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if (lip)
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cur->item = xfs_ail_next(ailp, lip);
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return lip;
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}
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/*
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* When the traversal is complete, we need to remove the cursor from the list
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* of traversing cursors.
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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_cursor *cur)
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{
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cur->item = NULL;
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list_del_init(&cur->list);
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}
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/*
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* Invalidate any cursor that is pointing to this item. This is called when an
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* item is removed from the AIL. Any cursor pointing to this object is now
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* invalid and the traversal needs to be terminated so it doesn't reference a
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* freed object. We set the low bit of the cursor item pointer so we can
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* distinguish between an invalidation and the end of the list when getting the
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* next item 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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list_for_each_entry(cur, &ailp->ail_cursors, list) {
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if (cur->item == lip)
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cur->item = (struct xfs_log_item *)
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((uintptr_t)cur->item | 1);
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}
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}
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/*
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* Find the first item in the AIL with the given @lsn by searching in ascending
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* LSN order and initialise the cursor to point to the next item for a
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* ascending traversal. Pass a @lsn of zero to initialise the cursor to the
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* first item in the AIL. Returns NULL if the list is empty.
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*/
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struct xfs_log_item *
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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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struct xfs_log_item *lip;
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xfs_trans_ail_cursor_init(ailp, cur);
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if (lsn == 0) {
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lip = xfs_ail_min(ailp);
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goto out;
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}
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list_for_each_entry(lip, &ailp->ail_head, 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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return NULL;
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out:
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if (lip)
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cur->item = xfs_ail_next(ailp, lip);
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return lip;
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}
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static struct xfs_log_item *
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__xfs_trans_ail_cursor_last(
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struct xfs_ail *ailp,
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xfs_lsn_t lsn)
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{
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struct xfs_log_item *lip;
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list_for_each_entry_reverse(lip, &ailp->ail_head, li_ail) {
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if (XFS_LSN_CMP(lip->li_lsn, lsn) <= 0)
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return lip;
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}
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return NULL;
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}
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/*
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* Find the last item in the AIL with the given @lsn by searching in descending
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* LSN order and initialise the cursor to point to that item. If there is no
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* item with the value of @lsn, then it sets the cursor to the last item with an
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* LSN lower than @lsn. Returns NULL if the list is empty.
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*/
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struct xfs_log_item *
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xfs_trans_ail_cursor_last(
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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_trans_ail_cursor_init(ailp, cur);
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cur->item = __xfs_trans_ail_cursor_last(ailp, lsn);
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return cur->item;
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}
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/*
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* Splice the log item list into the AIL at the given LSN. We splice to the
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* tail of the given LSN to maintain insert order for push traversals. The
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* cursor is optional, allowing repeated updates to the same LSN to avoid
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* repeated traversals. This should not be called with an empty list.
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*/
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static void
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xfs_ail_splice(
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struct xfs_ail *ailp,
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struct xfs_ail_cursor *cur,
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struct list_head *list,
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xfs_lsn_t lsn)
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{
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struct xfs_log_item *lip;
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ASSERT(!list_empty(list));
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/*
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* Use the cursor to determine the insertion point if one is
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* provided. If not, or if the one we got is not valid,
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* find the place in the AIL where the items belong.
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*/
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lip = cur ? cur->item : NULL;
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if (!lip || (uintptr_t)lip & 1)
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lip = __xfs_trans_ail_cursor_last(ailp, lsn);
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/*
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* If a cursor is provided, we know we're processing the AIL
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* in lsn order, and future items to be spliced in will
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* follow the last one being inserted now. Update the
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* cursor to point to that last item, now while we have a
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* reliable pointer to it.
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*/
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if (cur)
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cur->item = list_entry(list->prev, struct xfs_log_item, li_ail);
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/*
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* Finally perform the splice. Unless the AIL was empty,
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* lip points to the item in the AIL _after_ which the new
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* items should go. If lip is null the AIL was empty, so
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* the new items go at the head of the AIL.
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*/
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if (lip)
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list_splice(list, &lip->li_ail);
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else
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list_splice(list, &ailp->ail_head);
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}
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/*
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* Delete the given item from the AIL. Return a pointer to the item.
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*/
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static void
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xfs_ail_delete(
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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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xfs_ail_check(ailp, lip);
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list_del(&lip->li_ail);
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xfs_trans_ail_cursor_clear(ailp, lip);
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}
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/*
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* Requeue a failed buffer for writeback.
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*
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* We clear the log item failed state here as well, but we have to be careful
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* about reference counts because the only active reference counts on the buffer
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* may be the failed log items. Hence if we clear the log item failed state
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* before queuing the buffer for IO we can release all active references to
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* the buffer and free it, leading to use after free problems in
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* xfs_buf_delwri_queue. It makes no difference to the buffer or log items which
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* order we process them in - the buffer is locked, and we own the buffer list
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* so nothing on them is going to change while we are performing this action.
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*
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* Hence we can safely queue the buffer for IO before we clear the failed log
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* item state, therefore always having an active reference to the buffer and
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* avoiding the transient zero-reference state that leads to use-after-free.
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*/
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static inline int
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xfsaild_resubmit_item(
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struct xfs_log_item *lip,
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struct list_head *buffer_list)
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{
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struct xfs_buf *bp = lip->li_buf;
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if (!xfs_buf_trylock(bp))
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return XFS_ITEM_LOCKED;
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if (!xfs_buf_delwri_queue(bp, buffer_list)) {
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xfs_buf_unlock(bp);
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return XFS_ITEM_FLUSHING;
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}
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/* protected by ail_lock */
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list_for_each_entry(lip, &bp->b_li_list, li_bio_list)
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xfs_clear_li_failed(lip);
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xfs_buf_unlock(bp);
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return XFS_ITEM_SUCCESS;
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}
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static inline uint
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xfsaild_push_item(
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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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/*
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* If log item pinning is enabled, skip the push and track the item as
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* pinned. This can help induce head-behind-tail conditions.
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*/
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if (XFS_TEST_ERROR(false, ailp->ail_mount, XFS_ERRTAG_LOG_ITEM_PIN))
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return XFS_ITEM_PINNED;
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/*
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* Consider the item pinned if a push callback is not defined so the
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* caller will force the log. This should only happen for intent items
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* as they are unpinned once the associated done item is committed to
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* the on-disk log.
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*/
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if (!lip->li_ops->iop_push)
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return XFS_ITEM_PINNED;
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if (test_bit(XFS_LI_FAILED, &lip->li_flags))
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return xfsaild_resubmit_item(lip, &ailp->ail_buf_list);
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return lip->li_ops->iop_push(lip, &ailp->ail_buf_list);
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}
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static long
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xfsaild_push(
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struct xfs_ail *ailp)
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{
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xfs_mount_t *mp = ailp->ail_mount;
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struct xfs_ail_cursor cur;
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struct xfs_log_item *lip;
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xfs_lsn_t lsn;
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xfs_lsn_t target;
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long tout;
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int stuck = 0;
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int flushing = 0;
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int count = 0;
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/*
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* If we encountered pinned items or did not finish writing out all
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* buffers the last time we ran, force the log first and wait for it
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* before pushing again.
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*/
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if (ailp->ail_log_flush && ailp->ail_last_pushed_lsn == 0 &&
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(!list_empty_careful(&ailp->ail_buf_list) ||
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xfs_ail_min_lsn(ailp))) {
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ailp->ail_log_flush = 0;
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XFS_STATS_INC(mp, xs_push_ail_flush);
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xfs_log_force(mp, XFS_LOG_SYNC);
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}
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spin_lock(&ailp->ail_lock);
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/* barrier matches the ail_target update in xfs_ail_push() */
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smp_rmb();
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target = ailp->ail_target;
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ailp->ail_target_prev = target;
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lip = xfs_trans_ail_cursor_first(ailp, &cur, ailp->ail_last_pushed_lsn);
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if (!lip) {
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/*
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* If the AIL is empty or our push has reached the end we are
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* done now.
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*/
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xfs_trans_ail_cursor_done(&cur);
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spin_unlock(&ailp->ail_lock);
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goto out_done;
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}
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XFS_STATS_INC(mp, xs_push_ail);
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lsn = lip->li_lsn;
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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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* Note that iop_push may unlock and reacquire the AIL lock. We
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* rely on the AIL cursor implementation to be able to deal with
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* the dropped lock.
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*/
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lock_result = xfsaild_push_item(ailp, lip);
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switch (lock_result) {
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case XFS_ITEM_SUCCESS:
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XFS_STATS_INC(mp, xs_push_ail_success);
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trace_xfs_ail_push(lip);
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ailp->ail_last_pushed_lsn = lsn;
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break;
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case XFS_ITEM_FLUSHING:
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/*
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* The item or its backing buffer is already being
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* flushed. The typical reason for that is that an
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* inode buffer is locked because we already pushed the
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* updates to it as part of inode clustering.
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*
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* We do not want to to stop flushing just because lots
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* of items are already being flushed, but we need to
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* re-try the flushing relatively soon if most of the
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* AIL is being flushed.
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*/
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XFS_STATS_INC(mp, xs_push_ail_flushing);
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trace_xfs_ail_flushing(lip);
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|
|
|
flushing++;
|
|
ailp->ail_last_pushed_lsn = lsn;
|
|
break;
|
|
|
|
case XFS_ITEM_PINNED:
|
|
XFS_STATS_INC(mp, xs_push_ail_pinned);
|
|
trace_xfs_ail_pinned(lip);
|
|
|
|
stuck++;
|
|
ailp->ail_log_flush++;
|
|
break;
|
|
case XFS_ITEM_LOCKED:
|
|
XFS_STATS_INC(mp, xs_push_ail_locked);
|
|
trace_xfs_ail_locked(lip);
|
|
|
|
stuck++;
|
|
break;
|
|
default:
|
|
ASSERT(0);
|
|
break;
|
|
}
|
|
|
|
count++;
|
|
|
|
/*
|
|
* Are there too many items we can't do anything with?
|
|
*
|
|
* If we we are skipping too many items because we can't flush
|
|
* them or they are already being flushed, we back off and
|
|
* given them time to complete whatever operation is being
|
|
* done. i.e. remove pressure from the AIL while we can't make
|
|
* progress so traversals don't slow down further inserts and
|
|
* removals to/from the AIL.
|
|
*
|
|
* The value of 100 is an arbitrary magic number based on
|
|
* observation.
|
|
*/
|
|
if (stuck > 100)
|
|
break;
|
|
|
|
lip = xfs_trans_ail_cursor_next(ailp, &cur);
|
|
if (lip == NULL)
|
|
break;
|
|
lsn = lip->li_lsn;
|
|
}
|
|
xfs_trans_ail_cursor_done(&cur);
|
|
spin_unlock(&ailp->ail_lock);
|
|
|
|
if (xfs_buf_delwri_submit_nowait(&ailp->ail_buf_list))
|
|
ailp->ail_log_flush++;
|
|
|
|
if (!count || XFS_LSN_CMP(lsn, target) >= 0) {
|
|
out_done:
|
|
/*
|
|
* We reached the target or the AIL is empty, so wait a bit
|
|
* longer for I/O to complete and remove pushed items from the
|
|
* AIL before we start the next scan from the start of the AIL.
|
|
*/
|
|
tout = 50;
|
|
ailp->ail_last_pushed_lsn = 0;
|
|
} else if (((stuck + flushing) * 100) / count > 90) {
|
|
/*
|
|
* Either there is a lot of contention on the AIL or we are
|
|
* stuck due to operations in progress. "Stuck" in this case
|
|
* is defined as >90% of the items we tried to push were stuck.
|
|
*
|
|
* Backoff a bit more to allow some I/O to complete before
|
|
* restarting from the start of the AIL. This prevents us from
|
|
* spinning on the same items, and if they are pinned will all
|
|
* the restart to issue a log force to unpin the stuck items.
|
|
*/
|
|
tout = 20;
|
|
ailp->ail_last_pushed_lsn = 0;
|
|
} else {
|
|
/*
|
|
* Assume we have more work to do in a short while.
|
|
*/
|
|
tout = 10;
|
|
}
|
|
|
|
return tout;
|
|
}
|
|
|
|
static int
|
|
xfsaild(
|
|
void *data)
|
|
{
|
|
struct xfs_ail *ailp = data;
|
|
long tout = 0; /* milliseconds */
|
|
unsigned int noreclaim_flag;
|
|
|
|
noreclaim_flag = memalloc_noreclaim_save();
|
|
set_freezable();
|
|
|
|
while (1) {
|
|
if (tout && tout <= 20)
|
|
set_current_state(TASK_KILLABLE);
|
|
else
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
|
|
/*
|
|
* Check kthread_should_stop() after we set the task state to
|
|
* guarantee that we either see the stop bit and exit or the
|
|
* task state is reset to runnable such that it's not scheduled
|
|
* out indefinitely and detects the stop bit at next iteration.
|
|
* A memory barrier is included in above task state set to
|
|
* serialize again kthread_stop().
|
|
*/
|
|
if (kthread_should_stop()) {
|
|
__set_current_state(TASK_RUNNING);
|
|
|
|
/*
|
|
* The caller forces out the AIL before stopping the
|
|
* thread in the common case, which means the delwri
|
|
* queue is drained. In the shutdown case, the queue may
|
|
* still hold relogged buffers that haven't been
|
|
* submitted because they were pinned since added to the
|
|
* queue.
|
|
*
|
|
* Log I/O error processing stales the underlying buffer
|
|
* and clears the delwri state, expecting the buf to be
|
|
* removed on the next submission attempt. That won't
|
|
* happen if we're shutting down, so this is the last
|
|
* opportunity to release such buffers from the queue.
|
|
*/
|
|
ASSERT(list_empty(&ailp->ail_buf_list) ||
|
|
XFS_FORCED_SHUTDOWN(ailp->ail_mount));
|
|
xfs_buf_delwri_cancel(&ailp->ail_buf_list);
|
|
break;
|
|
}
|
|
|
|
spin_lock(&ailp->ail_lock);
|
|
|
|
/*
|
|
* Idle if the AIL is empty and we are not racing with a target
|
|
* update. We check the AIL after we set the task to a sleep
|
|
* state to guarantee that we either catch an ail_target update
|
|
* or that a wake_up resets the state to TASK_RUNNING.
|
|
* Otherwise, we run the risk of sleeping indefinitely.
|
|
*
|
|
* The barrier matches the ail_target update in xfs_ail_push().
|
|
*/
|
|
smp_rmb();
|
|
if (!xfs_ail_min(ailp) &&
|
|
ailp->ail_target == ailp->ail_target_prev) {
|
|
spin_unlock(&ailp->ail_lock);
|
|
freezable_schedule();
|
|
tout = 0;
|
|
continue;
|
|
}
|
|
spin_unlock(&ailp->ail_lock);
|
|
|
|
if (tout)
|
|
freezable_schedule_timeout(msecs_to_jiffies(tout));
|
|
|
|
__set_current_state(TASK_RUNNING);
|
|
|
|
try_to_freeze();
|
|
|
|
tout = xfsaild_push(ailp);
|
|
}
|
|
|
|
memalloc_noreclaim_restore(noreclaim_flag);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This routine is called to move the tail of the AIL forward. It does this by
|
|
* trying to flush items in the AIL whose lsns are below the given
|
|
* threshold_lsn.
|
|
*
|
|
* The push is run asynchronously in a workqueue, which means the caller needs
|
|
* to handle waiting on the async flush for space to become available.
|
|
* We don't want to interrupt any push that is in progress, hence we only queue
|
|
* work if we set the pushing bit appropriately.
|
|
*
|
|
* We do this unlocked - we only need to know whether there is anything in the
|
|
* AIL at the time we are called. We don't need to access the contents of
|
|
* any of the objects, so the lock is not needed.
|
|
*/
|
|
void
|
|
xfs_ail_push(
|
|
struct xfs_ail *ailp,
|
|
xfs_lsn_t threshold_lsn)
|
|
{
|
|
struct xfs_log_item *lip;
|
|
|
|
lip = xfs_ail_min(ailp);
|
|
if (!lip || XFS_FORCED_SHUTDOWN(ailp->ail_mount) ||
|
|
XFS_LSN_CMP(threshold_lsn, ailp->ail_target) <= 0)
|
|
return;
|
|
|
|
/*
|
|
* Ensure that the new target is noticed in push code before it clears
|
|
* the XFS_AIL_PUSHING_BIT.
|
|
*/
|
|
smp_wmb();
|
|
xfs_trans_ail_copy_lsn(ailp, &ailp->ail_target, &threshold_lsn);
|
|
smp_wmb();
|
|
|
|
wake_up_process(ailp->ail_task);
|
|
}
|
|
|
|
/*
|
|
* Push out all items in the AIL immediately
|
|
*/
|
|
void
|
|
xfs_ail_push_all(
|
|
struct xfs_ail *ailp)
|
|
{
|
|
xfs_lsn_t threshold_lsn = xfs_ail_max_lsn(ailp);
|
|
|
|
if (threshold_lsn)
|
|
xfs_ail_push(ailp, threshold_lsn);
|
|
}
|
|
|
|
/*
|
|
* Push out all items in the AIL immediately and wait until the AIL is empty.
|
|
*/
|
|
void
|
|
xfs_ail_push_all_sync(
|
|
struct xfs_ail *ailp)
|
|
{
|
|
struct xfs_log_item *lip;
|
|
DEFINE_WAIT(wait);
|
|
|
|
spin_lock(&ailp->ail_lock);
|
|
while ((lip = xfs_ail_max(ailp)) != NULL) {
|
|
prepare_to_wait(&ailp->ail_empty, &wait, TASK_UNINTERRUPTIBLE);
|
|
ailp->ail_target = lip->li_lsn;
|
|
wake_up_process(ailp->ail_task);
|
|
spin_unlock(&ailp->ail_lock);
|
|
schedule();
|
|
spin_lock(&ailp->ail_lock);
|
|
}
|
|
spin_unlock(&ailp->ail_lock);
|
|
|
|
finish_wait(&ailp->ail_empty, &wait);
|
|
}
|
|
|
|
void
|
|
xfs_ail_update_finish(
|
|
struct xfs_ail *ailp,
|
|
xfs_lsn_t old_lsn) __releases(ailp->ail_lock)
|
|
{
|
|
struct xfs_mount *mp = ailp->ail_mount;
|
|
|
|
/* if the tail lsn hasn't changed, don't do updates or wakeups. */
|
|
if (!old_lsn || old_lsn == __xfs_ail_min_lsn(ailp)) {
|
|
spin_unlock(&ailp->ail_lock);
|
|
return;
|
|
}
|
|
|
|
if (!XFS_FORCED_SHUTDOWN(mp))
|
|
xlog_assign_tail_lsn_locked(mp);
|
|
|
|
if (list_empty(&ailp->ail_head))
|
|
wake_up_all(&ailp->ail_empty);
|
|
spin_unlock(&ailp->ail_lock);
|
|
xfs_log_space_wake(mp);
|
|
}
|
|
|
|
/*
|
|
* xfs_trans_ail_update - bulk AIL insertion operation.
|
|
*
|
|
* @xfs_trans_ail_update takes an array of log items that all need to be
|
|
* positioned at the same LSN in the AIL. If an item is not in the AIL, it will
|
|
* be added. Otherwise, it will be repositioned by removing it and re-adding
|
|
* it to the AIL. If we move the first item in the AIL, update the log tail to
|
|
* match the new minimum LSN in the AIL.
|
|
*
|
|
* This function takes the AIL lock once to execute the update operations on
|
|
* all the items in the array, and as such should not be called with the AIL
|
|
* lock held. As a result, once we have the AIL lock, we need to check each log
|
|
* item LSN to confirm it needs to be moved forward in the AIL.
|
|
*
|
|
* To optimise the insert operation, we delete all the items from the AIL in
|
|
* the first pass, moving them into a temporary list, then splice the temporary
|
|
* list into the correct position in the AIL. This avoids needing to do an
|
|
* insert operation on every item.
|
|
*
|
|
* This function must be called with the AIL lock held. The lock is dropped
|
|
* before returning.
|
|
*/
|
|
void
|
|
xfs_trans_ail_update_bulk(
|
|
struct xfs_ail *ailp,
|
|
struct xfs_ail_cursor *cur,
|
|
struct xfs_log_item **log_items,
|
|
int nr_items,
|
|
xfs_lsn_t lsn) __releases(ailp->ail_lock)
|
|
{
|
|
struct xfs_log_item *mlip;
|
|
xfs_lsn_t tail_lsn = 0;
|
|
int i;
|
|
LIST_HEAD(tmp);
|
|
|
|
ASSERT(nr_items > 0); /* Not required, but true. */
|
|
mlip = xfs_ail_min(ailp);
|
|
|
|
for (i = 0; i < nr_items; i++) {
|
|
struct xfs_log_item *lip = log_items[i];
|
|
if (test_and_set_bit(XFS_LI_IN_AIL, &lip->li_flags)) {
|
|
/* check if we really need to move the item */
|
|
if (XFS_LSN_CMP(lsn, lip->li_lsn) <= 0)
|
|
continue;
|
|
|
|
trace_xfs_ail_move(lip, lip->li_lsn, lsn);
|
|
if (mlip == lip && !tail_lsn)
|
|
tail_lsn = lip->li_lsn;
|
|
|
|
xfs_ail_delete(ailp, lip);
|
|
} else {
|
|
trace_xfs_ail_insert(lip, 0, lsn);
|
|
}
|
|
lip->li_lsn = lsn;
|
|
list_add(&lip->li_ail, &tmp);
|
|
}
|
|
|
|
if (!list_empty(&tmp))
|
|
xfs_ail_splice(ailp, cur, &tmp, lsn);
|
|
|
|
xfs_ail_update_finish(ailp, tail_lsn);
|
|
}
|
|
|
|
/* Insert a log item into the AIL. */
|
|
void
|
|
xfs_trans_ail_insert(
|
|
struct xfs_ail *ailp,
|
|
struct xfs_log_item *lip,
|
|
xfs_lsn_t lsn)
|
|
{
|
|
spin_lock(&ailp->ail_lock);
|
|
xfs_trans_ail_update_bulk(ailp, NULL, &lip, 1, lsn);
|
|
}
|
|
|
|
/*
|
|
* Delete one log item from the AIL.
|
|
*
|
|
* If this item was at the tail of the AIL, return the LSN of the log item so
|
|
* that we can use it to check if the LSN of the tail of the log has moved
|
|
* when finishing up the AIL delete process in xfs_ail_update_finish().
|
|
*/
|
|
xfs_lsn_t
|
|
xfs_ail_delete_one(
|
|
struct xfs_ail *ailp,
|
|
struct xfs_log_item *lip)
|
|
{
|
|
struct xfs_log_item *mlip = xfs_ail_min(ailp);
|
|
xfs_lsn_t lsn = lip->li_lsn;
|
|
|
|
trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
|
|
xfs_ail_delete(ailp, lip);
|
|
xfs_clear_li_failed(lip);
|
|
clear_bit(XFS_LI_IN_AIL, &lip->li_flags);
|
|
lip->li_lsn = 0;
|
|
|
|
if (mlip == lip)
|
|
return lsn;
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
xfs_trans_ail_delete(
|
|
struct xfs_log_item *lip,
|
|
int shutdown_type)
|
|
{
|
|
struct xfs_ail *ailp = lip->li_ailp;
|
|
struct xfs_mount *mp = ailp->ail_mount;
|
|
xfs_lsn_t tail_lsn;
|
|
|
|
spin_lock(&ailp->ail_lock);
|
|
if (!test_bit(XFS_LI_IN_AIL, &lip->li_flags)) {
|
|
spin_unlock(&ailp->ail_lock);
|
|
if (shutdown_type && !XFS_FORCED_SHUTDOWN(mp)) {
|
|
xfs_alert_tag(mp, XFS_PTAG_AILDELETE,
|
|
"%s: attempting to delete a log item that is not in the AIL",
|
|
__func__);
|
|
xfs_force_shutdown(mp, shutdown_type);
|
|
}
|
|
return;
|
|
}
|
|
|
|
/* xfs_ail_update_finish() drops the AIL lock */
|
|
tail_lsn = xfs_ail_delete_one(ailp, lip);
|
|
xfs_ail_update_finish(ailp, tail_lsn);
|
|
}
|
|
|
|
int
|
|
xfs_trans_ail_init(
|
|
xfs_mount_t *mp)
|
|
{
|
|
struct xfs_ail *ailp;
|
|
|
|
ailp = kmem_zalloc(sizeof(struct xfs_ail), KM_MAYFAIL);
|
|
if (!ailp)
|
|
return -ENOMEM;
|
|
|
|
ailp->ail_mount = mp;
|
|
INIT_LIST_HEAD(&ailp->ail_head);
|
|
INIT_LIST_HEAD(&ailp->ail_cursors);
|
|
spin_lock_init(&ailp->ail_lock);
|
|
INIT_LIST_HEAD(&ailp->ail_buf_list);
|
|
init_waitqueue_head(&ailp->ail_empty);
|
|
|
|
ailp->ail_task = kthread_run(xfsaild, ailp, "xfsaild/%s",
|
|
ailp->ail_mount->m_super->s_id);
|
|
if (IS_ERR(ailp->ail_task))
|
|
goto out_free_ailp;
|
|
|
|
mp->m_ail = ailp;
|
|
return 0;
|
|
|
|
out_free_ailp:
|
|
kmem_free(ailp);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
void
|
|
xfs_trans_ail_destroy(
|
|
xfs_mount_t *mp)
|
|
{
|
|
struct xfs_ail *ailp = mp->m_ail;
|
|
|
|
kthread_stop(ailp->ail_task);
|
|
kmem_free(ailp);
|
|
}
|