| Message ID | 20200522035029.3022405-24-david@fromorbit.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | xfs: rework inode flushing to make inode reclaim fully asynchronous | expand |
On Fri, May 22, 2020 at 01:50:28PM +1000, Dave Chinner wrote: > From: Dave Chinner <dchinner@redhat.com> > > xfs_iflush_done() does 3 distinct operations to the inodes attached > to the buffer. Separate these operations out into functions so that > it is easier to modify these operations independently in future. > > Signed-off-by: Dave Chinner <dchinner@redhat.com> Seems like a fairly simple refactoring, Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> --D > --- > fs/xfs/xfs_inode_item.c | 156 +++++++++++++++++++++------------------- > 1 file changed, 82 insertions(+), 74 deletions(-) > > diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c > index af4764f97a339..4dd4f45dcc46e 100644 > --- a/fs/xfs/xfs_inode_item.c > +++ b/fs/xfs/xfs_inode_item.c > @@ -662,104 +662,67 @@ xfs_inode_item_destroy( > > > /* > - * This is the inode flushing I/O completion routine. It is called > - * from interrupt level when the buffer containing the inode is > - * flushed to disk. It is responsible for removing the inode item > - * from the AIL if it has not been re-logged, and unlocking the inode's > - * flush lock. > - * > - * To reduce AIL lock traffic as much as possible, we scan the buffer log item > - * list for other inodes that will run this function. We remove them from the > - * buffer list so we can process all the inode IO completions in one AIL lock > - * traversal. > - * > - * Note: Now that we attach the log item to the buffer when we first log the > - * inode in memory, we can have unflushed inodes on the buffer list here. These > - * inodes will have a zero ili_last_fields, so skip over them here. > + * We only want to pull the item from the AIL if it is actually there > + * and its location in the log has not changed since we started the > + * flush. Thus, we only bother if the inode's lsn has not changed. > */ > void > -xfs_iflush_done( > - struct xfs_buf *bp) > +xfs_iflush_ail_updates( > + struct xfs_ail *ailp, > + struct list_head *list) > { > - struct xfs_inode_log_item *iip; > - struct xfs_log_item *lip, *n; > - struct xfs_ail *ailp = bp->b_mount->m_ail; > - int need_ail = 0; > - LIST_HEAD(tmp); > + struct xfs_log_item *lip; > + xfs_lsn_t tail_lsn = 0; > > - /* > - * Pull the attached inodes from the buffer one at a time and take the > - * appropriate action on them. > - */ > - list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) { > - iip = INODE_ITEM(lip); > - if (!iip->ili_last_fields) > - continue; > + /* this is an opencoded batch version of xfs_trans_ail_delete */ > + spin_lock(&ailp->ail_lock); > + list_for_each_entry(lip, list, li_bio_list) { > + struct xfs_inode_log_item *iip = INODE_ITEM(lip); > + xfs_lsn_t lsn; > > - if (xfs_iflags_test(iip->ili_inode, XFS_ISTALE)) { > - xfs_iflush_abort(iip->ili_inode); > + if (iip->ili_flush_lsn != lip->li_lsn) { > + xfs_clear_li_failed(lip); > continue; > } > > - list_move_tail(&lip->li_bio_list, &tmp); > - > - /* Do an unlocked check for needing the AIL lock. */ > - if (iip->ili_flush_lsn == lip->li_lsn || > - test_bit(XFS_LI_FAILED, &lip->li_flags)) > - need_ail++; > + lsn = xfs_ail_delete_one(ailp, lip); > + if (!tail_lsn && lsn) > + tail_lsn = lsn; > } > + xfs_ail_update_finish(ailp, tail_lsn); > +} > > - /* > - * We only want to pull the item from the AIL if it is actually there > - * and its location in the log has not changed since we started the > - * flush. Thus, we only bother if the inode's lsn has not changed. > - */ > - if (need_ail) { > - xfs_lsn_t tail_lsn = 0; > - > - /* this is an opencoded batch version of xfs_trans_ail_delete */ > - spin_lock(&ailp->ail_lock); > - list_for_each_entry(lip, &tmp, li_bio_list) { > - iip = INODE_ITEM(lip); > - if (iip->ili_flush_lsn == lip->li_lsn) { > - xfs_lsn_t lsn = xfs_ail_delete_one(ailp, lip); > - if (!tail_lsn && lsn) > - tail_lsn = lsn; > - } else { > - xfs_clear_li_failed(lip); > - } > - } > - xfs_ail_update_finish(ailp, tail_lsn); > - } > +/* > + * Walk the list of inodes that have completed their IOs. If they are clean > + * remove them from the list and dissociate them from the buffer. Buffers that > + * are still dirty remain linked to the buffer and on the list. Caller must > + * handle them appropriately. > + */ > +void > +xfs_iflush_finish( > + struct xfs_buf *bp, > + struct list_head *list) > +{ > + struct xfs_log_item *lip, *n; > > - /* > - * Clean up and unlock the flush lock now we are done. We can clear the > - * ili_last_fields bits now that we know that the data corresponding to > - * them is safely on disk. > - */ > - list_for_each_entry_safe(lip, n, &tmp, li_bio_list) { > + list_for_each_entry_safe(lip, n, list, li_bio_list) { > + struct xfs_inode_log_item *iip = INODE_ITEM(lip); > bool drop_buffer = false; > > - list_del_init(&lip->li_bio_list); > - iip = INODE_ITEM(lip); > - > spin_lock(&iip->ili_lock); > iip->ili_last_fields = 0; > iip->ili_flush_lsn = 0; > > /* > * Remove the reference to the cluster buffer if the inode is > - * clean in memory. Drop the buffer reference once we've dropped > - * the locks we hold. If the inode is dirty in memory, we need > - * to put the inode item back on the buffer list for another > - * pass through the flush machinery. > + * clean in memory and drop the buffer reference once we've > + * dropped the locks we hold. > */ > ASSERT(iip->ili_item.li_buf == bp); > if (!iip->ili_fields) { > iip->ili_item.li_buf = NULL; > + list_del_init(&lip->li_bio_list); > drop_buffer = true; > - } else { > - list_add(&lip->li_bio_list, &bp->b_li_list); > } > spin_unlock(&iip->ili_lock); > xfs_ifunlock(iip->ili_inode); > @@ -768,6 +731,51 @@ xfs_iflush_done( > } > } > > +/* > + * Inode buffer IO completion routine. It is responsible for removing inodes > + * attached to the buffer from the AIL if they have not been re-logged, as well > + * as completing the flush and unlocking the inode. > + */ > +void > +xfs_iflush_done( > + struct xfs_buf *bp) > +{ > + struct xfs_log_item *lip, *n; > + LIST_HEAD(flushed_inodes); > + LIST_HEAD(ail_updates); > + > + /* > + * Pull the attached inodes from the buffer one at a time and take the > + * appropriate action on them. > + */ > + list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) { > + struct xfs_inode_log_item *iip = INODE_ITEM(lip); > + if (!iip->ili_last_fields) > + continue; > + > + if (xfs_iflags_test(iip->ili_inode, XFS_ISTALE)) { > + xfs_iflush_abort(iip->ili_inode); > + continue; > + } > + > + /* Do an unlocked check for needing the AIL lock. */ > + if (iip->ili_flush_lsn == lip->li_lsn || > + test_bit(XFS_LI_FAILED, &lip->li_flags)) > + list_move_tail(&lip->li_bio_list, &ail_updates); > + else > + list_move_tail(&lip->li_bio_list, &flushed_inodes); > + } > + > + if (!list_empty(&ail_updates)) { > + xfs_iflush_ail_updates(bp->b_mount->m_ail, &ail_updates); > + list_splice_tail(&ail_updates, &flushed_inodes); > + } > + > + xfs_iflush_finish(bp, &flushed_inodes); > + if (!list_empty(&flushed_inodes)) > + list_splice_tail(&flushed_inodes, &bp->b_li_list); > +} > + > /* > * This is the inode flushing abort routine. It is called from xfs_iflush when > * the filesystem is shutting down to clean up the inode state. It is > -- > 2.26.2.761.g0e0b3e54be >
On Fri, May 22, 2020 at 01:50:28PM +1000, Dave Chinner wrote: > +xfs_iflush_ail_updates( > + struct xfs_ail *ailp, > + struct list_head *list) > { > + struct xfs_log_item *lip; > + xfs_lsn_t tail_lsn = 0; > > + spin_lock(&ailp->ail_lock); > + list_for_each_entry(lip, list, li_bio_list) { > + struct xfs_inode_log_item *iip = INODE_ITEM(lip); > + xfs_lsn_t lsn; > > + if (iip->ili_flush_lsn != lip->li_lsn) { > + xfs_clear_li_failed(lip); > continue; > } > > + lsn = xfs_ail_delete_one(ailp, lip); > + if (!tail_lsn && lsn) > + tail_lsn = lsn; iip is only used once, this could be shortened by using INODE_ITEM() directly in the if expession: if (INODE_ITEM(lip)->ili_flush_lsn != lip->li_lsn) { > + list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) { > + struct xfs_inode_log_item *iip = INODE_ITEM(lip); > + if (!iip->ili_last_fields) > + continue; Please add an empty line after the variable declaration.
diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c index af4764f97a339..4dd4f45dcc46e 100644 --- a/fs/xfs/xfs_inode_item.c +++ b/fs/xfs/xfs_inode_item.c @@ -662,104 +662,67 @@ xfs_inode_item_destroy( /* - * This is the inode flushing I/O completion routine. It is called - * from interrupt level when the buffer containing the inode is - * flushed to disk. It is responsible for removing the inode item - * from the AIL if it has not been re-logged, and unlocking the inode's - * flush lock. - * - * To reduce AIL lock traffic as much as possible, we scan the buffer log item - * list for other inodes that will run this function. We remove them from the - * buffer list so we can process all the inode IO completions in one AIL lock - * traversal. - * - * Note: Now that we attach the log item to the buffer when we first log the - * inode in memory, we can have unflushed inodes on the buffer list here. These - * inodes will have a zero ili_last_fields, so skip over them here. + * We only want to pull the item from the AIL if it is actually there + * and its location in the log has not changed since we started the + * flush. Thus, we only bother if the inode's lsn has not changed. */ void -xfs_iflush_done( - struct xfs_buf *bp) +xfs_iflush_ail_updates( + struct xfs_ail *ailp, + struct list_head *list) { - struct xfs_inode_log_item *iip; - struct xfs_log_item *lip, *n; - struct xfs_ail *ailp = bp->b_mount->m_ail; - int need_ail = 0; - LIST_HEAD(tmp); + struct xfs_log_item *lip; + xfs_lsn_t tail_lsn = 0; - /* - * Pull the attached inodes from the buffer one at a time and take the - * appropriate action on them. - */ - list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) { - iip = INODE_ITEM(lip); - if (!iip->ili_last_fields) - continue; + /* this is an opencoded batch version of xfs_trans_ail_delete */ + spin_lock(&ailp->ail_lock); + list_for_each_entry(lip, list, li_bio_list) { + struct xfs_inode_log_item *iip = INODE_ITEM(lip); + xfs_lsn_t lsn; - if (xfs_iflags_test(iip->ili_inode, XFS_ISTALE)) { - xfs_iflush_abort(iip->ili_inode); + if (iip->ili_flush_lsn != lip->li_lsn) { + xfs_clear_li_failed(lip); continue; } - list_move_tail(&lip->li_bio_list, &tmp); - - /* Do an unlocked check for needing the AIL lock. */ - if (iip->ili_flush_lsn == lip->li_lsn || - test_bit(XFS_LI_FAILED, &lip->li_flags)) - need_ail++; + lsn = xfs_ail_delete_one(ailp, lip); + if (!tail_lsn && lsn) + tail_lsn = lsn; } + xfs_ail_update_finish(ailp, tail_lsn); +} - /* - * We only want to pull the item from the AIL if it is actually there - * and its location in the log has not changed since we started the - * flush. Thus, we only bother if the inode's lsn has not changed. - */ - if (need_ail) { - xfs_lsn_t tail_lsn = 0; - - /* this is an opencoded batch version of xfs_trans_ail_delete */ - spin_lock(&ailp->ail_lock); - list_for_each_entry(lip, &tmp, li_bio_list) { - iip = INODE_ITEM(lip); - if (iip->ili_flush_lsn == lip->li_lsn) { - xfs_lsn_t lsn = xfs_ail_delete_one(ailp, lip); - if (!tail_lsn && lsn) - tail_lsn = lsn; - } else { - xfs_clear_li_failed(lip); - } - } - xfs_ail_update_finish(ailp, tail_lsn); - } +/* + * Walk the list of inodes that have completed their IOs. If they are clean + * remove them from the list and dissociate them from the buffer. Buffers that + * are still dirty remain linked to the buffer and on the list. Caller must + * handle them appropriately. + */ +void +xfs_iflush_finish( + struct xfs_buf *bp, + struct list_head *list) +{ + struct xfs_log_item *lip, *n; - /* - * Clean up and unlock the flush lock now we are done. We can clear the - * ili_last_fields bits now that we know that the data corresponding to - * them is safely on disk. - */ - list_for_each_entry_safe(lip, n, &tmp, li_bio_list) { + list_for_each_entry_safe(lip, n, list, li_bio_list) { + struct xfs_inode_log_item *iip = INODE_ITEM(lip); bool drop_buffer = false; - list_del_init(&lip->li_bio_list); - iip = INODE_ITEM(lip); - spin_lock(&iip->ili_lock); iip->ili_last_fields = 0; iip->ili_flush_lsn = 0; /* * Remove the reference to the cluster buffer if the inode is - * clean in memory. Drop the buffer reference once we've dropped - * the locks we hold. If the inode is dirty in memory, we need - * to put the inode item back on the buffer list for another - * pass through the flush machinery. + * clean in memory and drop the buffer reference once we've + * dropped the locks we hold. */ ASSERT(iip->ili_item.li_buf == bp); if (!iip->ili_fields) { iip->ili_item.li_buf = NULL; + list_del_init(&lip->li_bio_list); drop_buffer = true; - } else { - list_add(&lip->li_bio_list, &bp->b_li_list); } spin_unlock(&iip->ili_lock); xfs_ifunlock(iip->ili_inode); @@ -768,6 +731,51 @@ xfs_iflush_done( } } +/* + * Inode buffer IO completion routine. It is responsible for removing inodes + * attached to the buffer from the AIL if they have not been re-logged, as well + * as completing the flush and unlocking the inode. + */ +void +xfs_iflush_done( + struct xfs_buf *bp) +{ + struct xfs_log_item *lip, *n; + LIST_HEAD(flushed_inodes); + LIST_HEAD(ail_updates); + + /* + * Pull the attached inodes from the buffer one at a time and take the + * appropriate action on them. + */ + list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) { + struct xfs_inode_log_item *iip = INODE_ITEM(lip); + if (!iip->ili_last_fields) + continue; + + if (xfs_iflags_test(iip->ili_inode, XFS_ISTALE)) { + xfs_iflush_abort(iip->ili_inode); + continue; + } + + /* Do an unlocked check for needing the AIL lock. */ + if (iip->ili_flush_lsn == lip->li_lsn || + test_bit(XFS_LI_FAILED, &lip->li_flags)) + list_move_tail(&lip->li_bio_list, &ail_updates); + else + list_move_tail(&lip->li_bio_list, &flushed_inodes); + } + + if (!list_empty(&ail_updates)) { + xfs_iflush_ail_updates(bp->b_mount->m_ail, &ail_updates); + list_splice_tail(&ail_updates, &flushed_inodes); + } + + xfs_iflush_finish(bp, &flushed_inodes); + if (!list_empty(&flushed_inodes)) + list_splice_tail(&flushed_inodes, &bp->b_li_list); +} + /* * This is the inode flushing abort routine. It is called from xfs_iflush when * the filesystem is shutting down to clean up the inode state. It is