goto out_unlock;
}
- error = xfs_iflush(ip, (flags & SYNC_WAIT) ?
- XFS_IFLUSH_SYNC : XFS_IFLUSH_DELWRI);
+ error = xfs_iflush(ip, flags);
out_unlock:
xfs_iunlock(ip, XFS_ILOCK_SHARED);
{
int count = 0, pincount;
+ xfs_reclaim_inodes(mp, 0);
xfs_flush_buftarg(mp->m_ddev_targp, 0);
- xfs_reclaim_inodes(mp, XFS_IFLUSH_DELWRI_ELSE_ASYNC);
/*
* This loop must run at least twice. The first instance of the loop
* will flush most meta data but that will generate more meta data
* (typically directory updates). Which then must be flushed and
- * logged before we can write the unmount record.
+ * logged before we can write the unmount record. We also so sync
+ * reclaim of inodes to catch any that the above delwri flush skipped.
*/
do {
+ xfs_reclaim_inodes(mp, SYNC_WAIT);
xfs_sync_attr(mp, SYNC_WAIT);
pincount = xfs_flush_buftarg(mp->m_ddev_targp, 1);
if (!pincount) {
if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
xfs_log_force(mp, 0);
- xfs_reclaim_inodes(mp, XFS_IFLUSH_DELWRI_ELSE_ASYNC);
+ xfs_reclaim_inodes(mp, 0);
/* dgc: errors ignored here */
error = xfs_qm_sync(mp, SYNC_TRYLOCK);
error = xfs_sync_fsdata(mp, SYNC_TRYLOCK);
* shutdown EIO unpin and reclaim
* clean, unpinned 0 reclaim
* stale, unpinned 0 reclaim
- * clean, pinned(*) 0 unpin and reclaim
- * stale, pinned 0 unpin and reclaim
- * dirty, async 0 block on flush lock, reclaim
- * dirty, sync flush 0 block on flush lock, reclaim
+ * clean, pinned(*) 0 requeue
+ * stale, pinned EAGAIN requeue
+ * dirty, delwri ok 0 requeue
+ * dirty, delwri blocked EAGAIN requeue
+ * dirty, sync flush 0 reclaim
*
* (*) dgc: I don't think the clean, pinned state is possible but it gets
* handled anyway given the order of checks implemented.
*
+ * As can be seen from the table, the return value of xfs_iflush() is not
+ * sufficient to correctly decide the reclaim action here. The checks in
+ * xfs_iflush() might look like duplicates, but they are not.
+ *
+ * Also, because we get the flush lock first, we know that any inode that has
+ * been flushed delwri has had the flush completed by the time we check that
+ * the inode is clean. The clean inode check needs to be done before flushing
+ * the inode delwri otherwise we would loop forever requeuing clean inodes as
+ * we cannot tell apart a successful delwri flush and a clean inode from the
+ * return value of xfs_iflush().
+ *
+ * Note that because the inode is flushed delayed write by background
+ * writeback, the flush lock may already be held here and waiting on it can
+ * result in very long latencies. Hence for sync reclaims, where we wait on the
+ * flush lock, the caller should push out delayed write inodes first before
+ * trying to reclaim them to minimise the amount of time spent waiting. For
+ * background relaim, we just requeue the inode for the next pass.
+ *
* Hence the order of actions after gaining the locks should be:
* bad => reclaim
* shutdown => unpin and reclaim
- * pinned => unpin
+ * pinned, delwri => requeue
+ * pinned, sync => unpin
* stale => reclaim
* clean => reclaim
- * dirty => flush, wait and reclaim
+ * dirty, delwri => flush and requeue
+ * dirty, sync => flush, wait and reclaim
*/
STATIC int
xfs_reclaim_inode(
struct xfs_perag *pag,
int sync_mode)
{
- int error;
+ int error = 0;
/*
* The radix tree lock here protects a thread in xfs_iget from racing
write_unlock(&pag->pag_ici_lock);
xfs_ilock(ip, XFS_ILOCK_EXCL);
- xfs_iflock(ip);
+ if (!xfs_iflock_nowait(ip)) {
+ if (!(sync_mode & SYNC_WAIT))
+ goto out;
+ xfs_iflock(ip);
+ }
if (is_bad_inode(VFS_I(ip)))
goto reclaim;
xfs_iunpin_wait(ip);
goto reclaim;
}
- if (xfs_ipincount(ip))
+ if (xfs_ipincount(ip)) {
+ if (!(sync_mode & SYNC_WAIT)) {
+ xfs_ifunlock(ip);
+ goto out;
+ }
xfs_iunpin_wait(ip);
+ }
if (xfs_iflags_test(ip, XFS_ISTALE))
goto reclaim;
if (xfs_inode_clean(ip))
/* Now we have an inode that needs flushing */
error = xfs_iflush(ip, sync_mode);
- if (!error) {
- switch(sync_mode) {
- case XFS_IFLUSH_DELWRI_ELSE_ASYNC:
- case XFS_IFLUSH_DELWRI:
- case XFS_IFLUSH_ASYNC:
- case XFS_IFLUSH_DELWRI_ELSE_SYNC:
- case XFS_IFLUSH_SYNC:
- /* IO issued, synchronise with IO completion */
- xfs_iflock(ip);
- break;
- default:
- ASSERT(0);
- break;
- }
+ if (sync_mode & SYNC_WAIT) {
+ xfs_iflock(ip);
+ goto reclaim;
}
+ /*
+ * When we have to flush an inode but don't have SYNC_WAIT set, we
+ * flush the inode out using a delwri buffer and wait for the next
+ * call into reclaim to find it in a clean state instead of waiting for
+ * it now. We also don't return errors here - if the error is transient
+ * then the next reclaim pass will flush the inode, and if the error
+ * is permanent then the next sync reclaim will relcaim the inode and
+ * pass on the error.
+ */
+ if (error && !XFS_FORCED_SHUTDOWN(ip->i_mount)) {
+ xfs_fs_cmn_err(CE_WARN, ip->i_mount,
+ "inode 0x%llx background reclaim flush failed with %d",
+ (long long)ip->i_ino, error);
+ }
+out:
+ xfs_iflags_clear(ip, XFS_IRECLAIM);
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ /*
+ * We could return EAGAIN here to make reclaim rescan the inode tree in
+ * a short while. However, this just burns CPU time scanning the tree
+ * waiting for IO to complete and xfssyncd never goes back to the idle
+ * state. Instead, return 0 to let the next scheduled background reclaim
+ * attempt to reclaim the inode again.
+ */
+ return 0;
+
reclaim:
xfs_ifunlock(ip);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_ireclaim(ip);
- return 0;
+ return error;
+
}
int
xfs_dinode_t *dip;
xfs_mount_t *mp;
int error;
- int noblock = (flags == XFS_IFLUSH_ASYNC_NOBLOCK);
- enum { INT_DELWRI = (1 << 0), INT_ASYNC = (1 << 1) };
XFS_STATS_INC(xs_iflush_count);
* in the same cluster are dirty, they will probably write the inode
* out for us if they occur after the log force completes.
*/
- if (noblock && xfs_ipincount(ip)) {
+ if (!(flags & SYNC_WAIT) && xfs_ipincount(ip)) {
xfs_iunpin_nowait(ip);
xfs_ifunlock(ip);
return EAGAIN;
return XFS_ERROR(EIO);
}
- /*
- * Decide how buffer will be flushed out. This is done before
- * the call to xfs_iflush_int because this field is zeroed by it.
- */
- if (iip != NULL && iip->ili_format.ilf_fields != 0) {
- /*
- * Flush out the inode buffer according to the directions
- * of the caller. In the cases where the caller has given
- * us a choice choose the non-delwri case. This is because
- * the inode is in the AIL and we need to get it out soon.
- */
- switch (flags) {
- case XFS_IFLUSH_SYNC:
- case XFS_IFLUSH_DELWRI_ELSE_SYNC:
- flags = 0;
- break;
- case XFS_IFLUSH_ASYNC_NOBLOCK:
- case XFS_IFLUSH_ASYNC:
- case XFS_IFLUSH_DELWRI_ELSE_ASYNC:
- flags = INT_ASYNC;
- break;
- case XFS_IFLUSH_DELWRI:
- flags = INT_DELWRI;
- break;
- default:
- ASSERT(0);
- flags = 0;
- break;
- }
- } else {
- switch (flags) {
- case XFS_IFLUSH_DELWRI_ELSE_SYNC:
- case XFS_IFLUSH_DELWRI_ELSE_ASYNC:
- case XFS_IFLUSH_DELWRI:
- flags = INT_DELWRI;
- break;
- case XFS_IFLUSH_ASYNC_NOBLOCK:
- case XFS_IFLUSH_ASYNC:
- flags = INT_ASYNC;
- break;
- case XFS_IFLUSH_SYNC:
- flags = 0;
- break;
- default:
- ASSERT(0);
- flags = 0;
- break;
- }
- }
-
/*
* Get the buffer containing the on-disk inode.
*/
error = xfs_itobp(mp, NULL, ip, &dip, &bp,
- noblock ? XBF_TRYLOCK : XBF_LOCK);
+ (flags & SYNC_WAIT) ? XBF_LOCK : XBF_TRYLOCK);
if (error || !bp) {
xfs_ifunlock(ip);
return error;
if (error)
goto cluster_corrupt_out;
- if (flags & INT_DELWRI) {
- xfs_bdwrite(mp, bp);
- } else if (flags & INT_ASYNC) {
- error = xfs_bawrite(mp, bp);
- } else {
+ if (flags & SYNC_WAIT)
error = xfs_bwrite(mp, bp);
- }
+ else
+ xfs_bdwrite(mp, bp);
return error;
corrupt_out:
iip = ip->i_itemp;
mp = ip->i_mount;
-
- /*
- * If the inode isn't dirty, then just release the inode
- * flush lock and do nothing.
- */
- if (xfs_inode_clean(ip)) {
- xfs_ifunlock(ip);
- return 0;
- }
-
/* set *dip = inode's place in the buffer */
dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
projects / mirror_ubuntu-disco-kernel.git / commitdiff