From: Christoph Hellwig hch@lst.de
commit 81a1e1c32ef474c20ccb9f730afe1ac25b1c62a4 upstream.
Directly return the error from xfs_bmap_longest_free_extent instead of breaking from the loop and handling it there, and use a done label to directly jump to the exist when we found a suitable perag structure to reduce the indentation level and pag/max_pag check complexity in the tail of the function.
Signed-off-by: Christoph Hellwig hch@lst.de Reviewed-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Carlos Maiolino cem@kernel.org Signed-off-by: Catherine Hoang catherine.hoang@oracle.com Acked-by: Darrick J. Wong djwong@kernel.org --- fs/xfs/xfs_filestream.c | 96 ++++++++++++++++++++--------------------- 1 file changed, 46 insertions(+), 50 deletions(-)
diff --git a/fs/xfs/xfs_filestream.c b/fs/xfs/xfs_filestream.c index f62b023f274e..4e1e83561218 100644 --- a/fs/xfs/xfs_filestream.c +++ b/fs/xfs/xfs_filestream.c @@ -67,22 +67,28 @@ xfs_filestream_pick_ag( xfs_extlen_t minfree, maxfree = 0; xfs_agnumber_t agno; bool first_pass = true; - int err;
/* 2% of an AG's blocks must be free for it to be chosen. */ minfree = mp->m_sb.sb_agblocks / 50;
restart: for_each_perag_wrap(mp, start_agno, agno, pag) { + int err; + trace_xfs_filestream_scan(pag, pino); + *longest = 0; err = xfs_bmap_longest_free_extent(pag, NULL, longest); if (err) { - if (err != -EAGAIN) - break; - /* Couldn't lock the AGF, skip this AG. */ - err = 0; - continue; + if (err == -EAGAIN) { + /* Couldn't lock the AGF, skip this AG. */ + err = 0; + continue; + } + xfs_perag_rele(pag); + if (max_pag) + xfs_perag_rele(max_pag); + return err; }
/* Keep track of the AG with the most free blocks. */ @@ -107,7 +113,9 @@ xfs_filestream_pick_ag( !(flags & XFS_PICK_USERDATA) || (flags & XFS_PICK_LOWSPACE))) { /* Break out, retaining the reference on the AG. */ - break; + if (max_pag) + xfs_perag_rele(max_pag); + goto done; } }
@@ -115,56 +123,44 @@ xfs_filestream_pick_ag( atomic_dec(&pag->pagf_fstrms); }
- if (err) { - xfs_perag_rele(pag); - if (max_pag) - xfs_perag_rele(max_pag); - return err; + /* + * Allow a second pass to give xfs_bmap_longest_free_extent() another + * attempt at locking AGFs that it might have skipped over before we + * fail. + */ + if (first_pass) { + first_pass = false; + goto restart; }
- if (!pag) { - /* - * Allow a second pass to give xfs_bmap_longest_free_extent() - * another attempt at locking AGFs that it might have skipped - * over before we fail. - */ - if (first_pass) { - first_pass = false; - goto restart; - } - - /* - * We must be low on data space, so run a final lowspace - * optimised selection pass if we haven't already. - */ - if (!(flags & XFS_PICK_LOWSPACE)) { - flags |= XFS_PICK_LOWSPACE; - goto restart; - } - - /* - * No unassociated AGs are available, so select the AG with the - * most free space, regardless of whether it's already in use by - * another filestream. It none suit, just use whatever AG we can - * grab. - */ - if (!max_pag) { - for_each_perag_wrap(args->mp, 0, start_agno, pag) { - max_pag = pag; - break; - } + /* + * We must be low on data space, so run a final lowspace optimised + * selection pass if we haven't already. + */ + if (!(flags & XFS_PICK_LOWSPACE)) { + flags |= XFS_PICK_LOWSPACE; + goto restart; + }
- /* Bail if there are no AGs at all to select from. */ - if (!max_pag) - return -ENOSPC; + /* + * No unassociated AGs are available, so select the AG with the most + * free space, regardless of whether it's already in use by another + * filestream. It none suit, just use whatever AG we can grab. + */ + if (!max_pag) { + for_each_perag_wrap(args->mp, 0, start_agno, pag) { + max_pag = pag; + break; }
- pag = max_pag; - atomic_inc(&pag->pagf_fstrms); - } else if (max_pag) { - xfs_perag_rele(max_pag); + /* Bail if there are no AGs at all to select from. */ + if (!max_pag) + return -ENOSPC; }
+ pag = max_pag; + atomic_inc(&pag->pagf_fstrms); +done: trace_xfs_filestream_pick(pag, pino); args->pag = pag; return 0;