We have historically decided that we want to preallocate the xfs_trans structure at writeback time so that we don't have to allocate on in the I/O completion handler. But we treat unwrittent extent and COW fork conversions different already, which proves that the transaction allocations in the end I/O handler are not a problem. Removing the preallocation gets rid of a lot of corner case code, and also ensures we only allocate one and log a transaction when actually required, as the ioend merging can reduce the number of actual i_size updates significantly.
Signed-off-by: Christoph Hellwig <h...@lst.de> --- fs/xfs/xfs_aops.c | 110 +++++----------------------------------------- fs/xfs/xfs_aops.h | 1 - 2 files changed, 12 insertions(+), 99 deletions(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 633baaaff7ae..017b87b7765f 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -130,44 +130,23 @@ static inline bool xfs_ioend_is_append(struct xfs_ioend *ioend) XFS_I(ioend->io_inode)->i_d.di_size; } -STATIC int -xfs_setfilesize_trans_alloc( - struct xfs_ioend *ioend) -{ - struct xfs_mount *mp = XFS_I(ioend->io_inode)->i_mount; - struct xfs_trans *tp; - int error; - - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp); - if (error) - return error; - - ioend->io_append_trans = tp; - - /* - * We may pass freeze protection with a transaction. So tell lockdep - * we released it. - */ - __sb_writers_release(ioend->io_inode->i_sb, SB_FREEZE_FS); - /* - * We hand off the transaction to the completion thread now, so - * clear the flag here. - */ - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); - return 0; -} - /* * Update on-disk file size now that data has been written to disk. */ -STATIC int -__xfs_setfilesize( +int +xfs_setfilesize( struct xfs_inode *ip, - struct xfs_trans *tp, xfs_off_t offset, size_t size) { + struct xfs_mount *mp = ip->i_mount; + struct xfs_trans *tp; xfs_fsize_t isize; + int error; + + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp); + if (error) + return error; xfs_ilock(ip, XFS_ILOCK_EXCL); isize = xfs_new_eof(ip, offset + size); @@ -186,48 +165,6 @@ __xfs_setfilesize( return xfs_trans_commit(tp); } -int -xfs_setfilesize( - struct xfs_inode *ip, - xfs_off_t offset, - size_t size) -{ - struct xfs_mount *mp = ip->i_mount; - struct xfs_trans *tp; - int error; - - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp); - if (error) - return error; - - return __xfs_setfilesize(ip, tp, offset, size); -} - -STATIC int -xfs_setfilesize_ioend( - struct xfs_ioend *ioend, - int error) -{ - struct xfs_inode *ip = XFS_I(ioend->io_inode); - struct xfs_trans *tp = ioend->io_append_trans; - - /* - * The transaction may have been allocated in the I/O submission thread, - * thus we need to mark ourselves as being in a transaction manually. - * Similarly for freeze protection. - */ - current_set_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); - __sb_writers_acquired(VFS_I(ip)->i_sb, SB_FREEZE_FS); - - /* we abort the update if there was an IO error */ - if (error) { - xfs_trans_cancel(tp); - return error; - } - - return __xfs_setfilesize(ip, tp, ioend->io_offset, ioend->io_size); -} - /* * IO write completion. */ @@ -267,12 +204,9 @@ xfs_end_ioend( error = xfs_reflink_end_cow(ip, offset, size); else if (ioend->io_type == IOMAP_UNWRITTEN) error = xfs_iomap_write_unwritten(ip, offset, size, false); - else - ASSERT(!xfs_ioend_is_append(ioend) || ioend->io_append_trans); - + if (!error && xfs_ioend_is_append(ioend)) + error = xfs_setfilesize(ip, offset, size); done: - if (ioend->io_append_trans) - error = xfs_setfilesize_ioend(ioend, error); list_replace_init(&ioend->io_list, &ioend_list); xfs_destroy_ioend(ioend, error); @@ -307,8 +241,6 @@ xfs_ioend_can_merge( return false; if (ioend->io_offset + ioend->io_size != next->io_offset) return false; - if (xfs_ioend_is_append(ioend) != xfs_ioend_is_append(next)) - return false; return true; } @@ -320,7 +252,6 @@ xfs_ioend_try_merge( { struct xfs_ioend *next_ioend; int ioend_error; - int error; if (list_empty(more_ioends)) return; @@ -334,10 +265,6 @@ xfs_ioend_try_merge( break; list_move_tail(&next_ioend->io_list, &ioend->io_list); ioend->io_size += next_ioend->io_size; - if (ioend->io_append_trans) { - error = xfs_setfilesize_ioend(next_ioend, 1); - ASSERT(error == 1); - } } } @@ -398,7 +325,7 @@ xfs_end_bio( if (ioend->io_fork == XFS_COW_FORK || ioend->io_type == IOMAP_UNWRITTEN || - ioend->io_append_trans != NULL) { + xfs_ioend_is_append(ioend)) { spin_lock_irqsave(&ip->i_ioend_lock, flags); if (list_empty(&ip->i_ioend_list)) WARN_ON_ONCE(!queue_work(mp->m_unwritten_workqueue, @@ -660,18 +587,6 @@ xfs_submit_ioend( memalloc_nofs_restore(nofs_flag); } - /* Reserve log space if we might write beyond the on-disk inode size. */ - if (!status && - (ioend->io_fork == XFS_COW_FORK || - ioend->io_type != IOMAP_UNWRITTEN) && - xfs_ioend_is_append(ioend) && - !ioend->io_append_trans) { - unsigned nofs_flag = memalloc_nofs_save(); - - status = xfs_setfilesize_trans_alloc(ioend); - memalloc_nofs_restore(nofs_flag); - } - ioend->io_bio->bi_private = ioend; ioend->io_bio->bi_end_io = xfs_end_bio; @@ -715,7 +630,6 @@ xfs_alloc_ioend( ioend->io_inode = inode; ioend->io_size = 0; ioend->io_offset = offset; - ioend->io_append_trans = NULL; ioend->io_bio = bio; return ioend; } diff --git a/fs/xfs/xfs_aops.h b/fs/xfs/xfs_aops.h index 72e30d1c3bdf..23c087f0bcbf 100644 --- a/fs/xfs/xfs_aops.h +++ b/fs/xfs/xfs_aops.h @@ -18,7 +18,6 @@ struct xfs_ioend { struct inode *io_inode; /* file being written to */ size_t io_size; /* size of the extent */ xfs_off_t io_offset; /* offset in the file */ - struct xfs_trans *io_append_trans;/* xact. for size update */ struct bio *io_bio; /* bio being built */ struct bio io_inline_bio; /* MUST BE LAST! */ }; -- 2.20.1