#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_log.h"
-#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
* Return a pointer to the first item in the AIL. If the AIL is empty, then
* return NULL.
*/
-static xfs_log_item_t *
+xfs_log_item_t *
xfs_ail_min(
struct xfs_ail *ailp)
{
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);
spin_unlock(&ailp->xa_lock);
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 = 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:
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
xfs_trans_ail_cursor_done(ailp, &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;
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();
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->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);
+
+ finish_wait(&ailp->xa_empty, &wait);
+}
+
/*
* xfs_trans_ail_update - bulk AIL insertion operation.
*
if (!list_empty(&tmp))
xfs_ail_splice(ailp, cur, &tmp, lsn);
- spin_unlock(&ailp->xa_lock);
- if (mlip_changed && !XFS_FORCED_SHUTDOWN(ailp->xa_mount)) {
- xlog_assign_tail_lsn(ailp->xa_mount);
+ if (mlip_changed) {
+ if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount))
+ xlog_assign_tail_lsn_locked(ailp->xa_mount);
+ spin_unlock(&ailp->xa_lock);
+
xfs_log_space_wake(ailp->xa_mount);
+ } else {
+ spin_unlock(&ailp->xa_lock);
}
}
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;
int mlip_changed = 0;
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;
}
if (mlip == lip)
mlip_changed = 1;
}
- spin_unlock(&ailp->xa_lock);
- if (mlip_changed && !XFS_FORCED_SHUTDOWN(ailp->xa_mount)) {
- xlog_assign_tail_lsn(ailp->xa_mount);
+ 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);
+
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)
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);
projects / firefly-linux-kernel-4.4.55.git / blobdiff