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Diffstat (limited to 'fs/xfs/xfs_trans_ail.c')
-rw-r--r--fs/xfs/xfs_trans_ail.c330
1 files changed, 134 insertions, 196 deletions
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index ed9252bcdac..cb0f3a84cc6 100644
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -18,16 +18,16 @@
*/
#include "xfs.h"
#include "xfs_fs.h"
-#include "xfs_types.h"
-#include "xfs_log.h"
-#include "xfs_inum.h"
-#include "xfs_trans.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
+#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_trace.h"
#include "xfs_error.h"
+#include "xfs_log.h"
#ifdef DEBUG
/*
@@ -56,40 +56,12 @@ xfs_ail_check(
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 */
}
#else /* !DEBUG */
#define xfs_ail_check(a,l)
#endif /* DEBUG */
/*
- * 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 last item in the AIL. If the AIL is empty, then
* return NULL.
*/
@@ -201,7 +173,6 @@ xfs_trans_ail_cursor_next(
*/
void
xfs_trans_ail_cursor_done(
- struct xfs_ail *ailp,
struct xfs_ail_cursor *cur)
{
cur->item = NULL;
@@ -364,86 +335,80 @@ xfsaild_push(
xfs_log_item_t *lip;
xfs_lsn_t lsn;
xfs_lsn_t target;
- long tout = 10;
+ long tout;
int stuck = 0;
+ int flushing = 0;
int count = 0;
- int push_xfsbufd = 0;
/*
- * If last time we ran we encountered pinned items, force the log first
- * and wait for it before pushing again.
+ * If we encountered pinned items or did not finish writing out all
+ * buffers the last time we ran, force the log first and wait for it
+ * before pushing again.
*/
- spin_lock(&ailp->xa_lock);
- if (ailp->xa_last_pushed_lsn == 0 && ailp->xa_log_flush &&
- !list_empty(&ailp->xa_ail)) {
+ if (ailp->xa_log_flush && ailp->xa_last_pushed_lsn == 0 &&
+ (!list_empty_careful(&ailp->xa_buf_list) ||
+ xfs_ail_min_lsn(ailp))) {
ailp->xa_log_flush = 0;
- spin_unlock(&ailp->xa_lock);
+
XFS_STATS_INC(xs_push_ail_flush);
xfs_log_force(mp, XFS_LOG_SYNC);
- spin_lock(&ailp->xa_lock);
}
+ spin_lock(&ailp->xa_lock);
+
+ /* barrier matches the xa_target update in xfs_ail_push() */
+ smp_rmb();
target = ailp->xa_target;
+ ailp->xa_target_prev = target;
+
lip = xfs_trans_ail_cursor_first(ailp, &cur, ailp->xa_last_pushed_lsn);
- if (!lip || XFS_FORCED_SHUTDOWN(mp)) {
+ if (!lip) {
/*
- * AIL is empty or our push has reached the end.
+ * If the AIL is empty or our push has reached the end we are
+ * done now.
*/
- xfs_trans_ail_cursor_done(ailp, &cur);
+ xfs_trans_ail_cursor_done(&cur);
spin_unlock(&ailp->xa_lock);
goto out_done;
}
XFS_STATS_INC(xs_push_ail);
- /*
- * While the item we are looking at is below the given threshold
- * try to flush it out. We'd like not to stop until we've at least
- * tried to push on everything in the AIL with an LSN less than
- * the given threshold.
- *
- * However, we will stop after a certain number of pushes and wait
- * for a reduced timeout to fire before pushing further. This
- * prevents use from spinning when we can't do anything or there is
- * lots of contention on the AIL lists.
- */
lsn = lip->li_lsn;
while ((XFS_LSN_CMP(lip->li_lsn, target) <= 0)) {
int lock_result;
+
/*
- * If we can lock the item without sleeping, unlock the AIL
- * lock and flush the item. Then re-grab the AIL lock so we
- * can look for the next item on the AIL. List changes are
- * handled by the AIL lookup functions internally
- *
- * If we can't lock the item, either its holder will flush it
- * or it is already being flushed or it is being relogged. In
- * any of these case it is being taken care of and we can just
- * skip to the next item in the list.
+ * Note that iop_push may unlock and reacquire the AIL lock. We
+ * rely on the AIL cursor implementation to be able to deal with
+ * the dropped lock.
*/
- lock_result = IOP_TRYLOCK(lip);
- spin_unlock(&ailp->xa_lock);
+ lock_result = lip->li_ops->iop_push(lip, &ailp->xa_buf_list);
switch (lock_result) {
case XFS_ITEM_SUCCESS:
XFS_STATS_INC(xs_push_ail_success);
trace_xfs_ail_push(lip);
- IOP_PUSH(lip);
ailp->xa_last_pushed_lsn = lsn;
break;
- case XFS_ITEM_PUSHBUF:
- XFS_STATS_INC(xs_push_ail_pushbuf);
- trace_xfs_ail_pushbuf(lip);
-
- if (!IOP_PUSHBUF(lip)) {
- trace_xfs_ail_pushbuf_pinned(lip);
- stuck++;
- ailp->xa_log_flush++;
- } else {
- ailp->xa_last_pushed_lsn = lsn;
- }
- push_xfsbufd = 1;
+ case XFS_ITEM_FLUSHING:
+ /*
+ * The item or its backing buffer is already beeing
+ * flushed. The typical reason for that is that an
+ * inode buffer is locked because we already pushed the
+ * updates to it as part of inode clustering.
+ *
+ * We do not want to to stop flushing just because lots
+ * of items are already beeing flushed, but we need to
+ * re-try the flushing relatively soon if most of the
+ * AIL is beeing flushed.
+ */
+ XFS_STATS_INC(xs_push_ail_flushing);
+ trace_xfs_ail_flushing(lip);
+
+ flushing++;
+ ailp->xa_last_pushed_lsn = lsn;
break;
case XFS_ITEM_PINNED:
@@ -453,28 +418,22 @@ xfsaild_push(
stuck++;
ailp->xa_log_flush++;
break;
-
case XFS_ITEM_LOCKED:
XFS_STATS_INC(xs_push_ail_locked);
trace_xfs_ail_locked(lip);
+
stuck++;
break;
-
default:
ASSERT(0);
break;
}
- spin_lock(&ailp->xa_lock);
- /* should we bother continuing? */
- if (XFS_FORCED_SHUTDOWN(mp))
- break;
- ASSERT(mp->m_log);
-
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
@@ -493,45 +452,39 @@ xfsaild_push(
break;
lsn = lip->li_lsn;
}
- xfs_trans_ail_cursor_done(ailp, &cur);
+ xfs_trans_ail_cursor_done(&cur);
spin_unlock(&ailp->xa_lock);
- if (push_xfsbufd) {
- /* we've got delayed write buffers to flush */
- wake_up_process(mp->m_ddev_targp->bt_task);
- }
+ if (xfs_buf_delwri_submit_nowait(&ailp->xa_buf_list))
+ ailp->xa_log_flush++;
- /* assume we have more work to do in a short while */
+ if (!count || XFS_LSN_CMP(lsn, target) >= 0) {
out_done:
- if (!count) {
- /* We're past our target or empty, so idle */
- ailp->xa_last_pushed_lsn = 0;
- ailp->xa_log_flush = 0;
-
- tout = 50;
- } else if (XFS_LSN_CMP(lsn, target) >= 0) {
/*
- * We reached the target 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.
+ * 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->xa_last_pushed_lsn = 0;
- } else if ((stuck * 100) / count > 90) {
+ } 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.
+ * 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.
+ * 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->xa_last_pushed_lsn = 0;
+ } else {
+ /*
+ * Assume we have more work to do in a short while.
+ */
+ tout = 10;
}
return tout;
@@ -544,13 +497,39 @@ xfsaild(
struct xfs_ail *ailp = data;
long tout = 0; /* milliseconds */
+ current->flags |= PF_MEMALLOC;
+
while (!kthread_should_stop()) {
if (tout && tout <= 20)
__set_current_state(TASK_KILLABLE);
else
__set_current_state(TASK_INTERRUPTIBLE);
- schedule_timeout(tout ?
- msecs_to_jiffies(tout) : MAX_SCHEDULE_TIMEOUT);
+
+ spin_lock(&ailp->xa_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 xa_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 xa_target update in xfs_ail_push().
+ */
+ smp_rmb();
+ if (!xfs_ail_min(ailp) &&
+ ailp->xa_target == ailp->xa_target_prev) {
+ spin_unlock(&ailp->xa_lock);
+ schedule();
+ tout = 0;
+ continue;
+ }
+ spin_unlock(&ailp->xa_lock);
+
+ if (tout)
+ schedule_timeout(msecs_to_jiffies(tout));
+
+ __set_current_state(TASK_RUNNING);
try_to_freeze();
@@ -611,48 +590,28 @@ xfs_ail_push_all(
}
/*
- * This is to be called when an item is unlocked that may have
- * been in the AIL. It will wake up the first member of the AIL
- * wait list if this item's unlocking might allow it to progress.
- * If the item is in the AIL, then we need to get the AIL lock
- * while doing our checking so we don't race with someone going
- * to sleep waiting for this event in xfs_trans_push_ail().
+ * Push out all items in the AIL immediately and wait until the AIL is empty.
*/
void
-xfs_trans_unlocked_item(
- struct xfs_ail *ailp,
- xfs_log_item_t *lip)
+xfs_ail_push_all_sync(
+ struct xfs_ail *ailp)
{
- xfs_log_item_t *min_lip;
+ struct xfs_log_item *lip;
+ DEFINE_WAIT(wait);
- /*
- * If we're forcibly shutting down, we may have
- * unlocked log items arbitrarily. The last thing
- * we want to do is to move the tail of the log
- * over some potentially valid data.
- */
- if (!(lip->li_flags & XFS_LI_IN_AIL) ||
- XFS_FORCED_SHUTDOWN(ailp->xa_mount)) {
- return;
+ spin_lock(&ailp->xa_lock);
+ while ((lip = xfs_ail_max(ailp)) != NULL) {
+ prepare_to_wait(&ailp->xa_empty, &wait, TASK_UNINTERRUPTIBLE);
+ ailp->xa_target = lip->li_lsn;
+ wake_up_process(ailp->xa_task);
+ spin_unlock(&ailp->xa_lock);
+ schedule();
+ spin_lock(&ailp->xa_lock);
}
+ spin_unlock(&ailp->xa_lock);
- /*
- * This is the one case where we can call into xfs_ail_min()
- * without holding the AIL lock because we only care about the
- * case where we are at the tail of the AIL. If the object isn't
- * at the tail, it doesn't matter what result we get back. This
- * is slightly racy because since we were just unlocked, we could
- * go to sleep between the call to xfs_ail_min and the call to
- * xfs_log_move_tail, have someone else lock us, commit to us disk,
- * move us out of the tail of the AIL, and then we wake up. However,
- * the call to xfs_log_move_tail() doesn't do anything if there's
- * not enough free space to wake people up so we're safe calling it.
- */
- min_lip = xfs_ail_min(ailp);
-
- if (min_lip == lip)
- xfs_log_move_tail(ailp->xa_mount, 1);
-} /* xfs_trans_unlocked_item */
+ finish_wait(&ailp->xa_empty, &wait);
+}
/*
* xfs_trans_ail_update - bulk AIL insertion operation.
@@ -685,7 +644,6 @@ xfs_trans_ail_update_bulk(
xfs_lsn_t lsn) __releases(ailp->xa_lock)
{
xfs_log_item_t *mlip;
- xfs_lsn_t tail_lsn;
int mlip_changed = 0;
int i;
LIST_HEAD(tmp);
@@ -700,11 +658,13 @@ xfs_trans_ail_update_bulk(
if (XFS_LSN_CMP(lsn, lip->li_lsn) <= 0)
continue;
+ trace_xfs_ail_move(lip, lip->li_lsn, lsn);
xfs_ail_delete(ailp, lip);
if (mlip == lip)
mlip_changed = 1;
} else {
lip->li_flags |= XFS_LI_IN_AIL;
+ trace_xfs_ail_insert(lip, 0, lsn);
}
lip->li_lsn = lsn;
list_add(&lip->li_ail, &tmp);
@@ -713,21 +673,15 @@ xfs_trans_ail_update_bulk(
if (!list_empty(&tmp))
xfs_ail_splice(ailp, cur, &tmp, lsn);
- if (!mlip_changed) {
+ if (mlip_changed) {
+ if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount))
+ xlog_assign_tail_lsn_locked(ailp->xa_mount);
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_log_space_wake(ailp->xa_mount);
+ } else {
+ spin_unlock(&ailp->xa_lock);
+ }
}
/*
@@ -755,10 +709,10 @@ void
xfs_trans_ail_delete_bulk(
struct xfs_ail *ailp,
struct xfs_log_item **log_items,
- int nr_items) __releases(ailp->xa_lock)
+ int nr_items,
+ int shutdown_type) __releases(ailp->xa_lock)
{
xfs_log_item_t *mlip;
- xfs_lsn_t tail_lsn;
int mlip_changed = 0;
int i;
@@ -774,11 +728,12 @@ xfs_trans_ail_delete_bulk(
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_CORRUPT_INCORE);
+ xfs_force_shutdown(mp, shutdown_type);
}
return;
}
+ trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
xfs_ail_delete(ailp, lip);
lip->li_flags &= ~XFS_LI_IN_AIL;
lip->li_lsn = 0;
@@ -786,38 +741,19 @@ xfs_trans_ail_delete_bulk(
mlip_changed = 1;
}
- if (!mlip_changed) {
+ if (mlip_changed) {
+ if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount))
+ xlog_assign_tail_lsn_locked(ailp->xa_mount);
+ if (list_empty(&ailp->xa_ail))
+ wake_up_all(&ailp->xa_empty);
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);
+ xfs_log_space_wake(ailp->xa_mount);
+ } else {
+ spin_unlock(&ailp->xa_lock);
+ }
}
-/*
- * 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)
@@ -832,6 +768,8 @@ xfs_trans_ail_init(
INIT_LIST_HEAD(&ailp->xa_ail);
INIT_LIST_HEAD(&ailp->xa_cursors);
spin_lock_init(&ailp->xa_lock);
+ INIT_LIST_HEAD(&ailp->xa_buf_list);
+ init_waitqueue_head(&ailp->xa_empty);
ailp->xa_task = kthread_run(xfsaild, ailp, "xfsaild/%s",
ailp->xa_mount->m_fsname);