From eb70aa2d8ed9a6fc3525f305226c550524390cd2 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 13 Feb 2023 09:14:55 +1100 Subject: xfs: use for_each_perag_wrap in xfs_filestream_pick_ag xfs_filestream_pick_ag() is now ready to rework to use for_each_perag_wrap() for iterating the perags during the AG selection scan. Signed-off-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/xfs_filestream.c | 101 ++++++++++++++++++++---------------------------- 1 file changed, 41 insertions(+), 60 deletions(-) (limited to 'fs/xfs/xfs_filestream.c') diff --git a/fs/xfs/xfs_filestream.c b/fs/xfs/xfs_filestream.c index c92429272ff7..71fa44485a2f 100644 --- a/fs/xfs/xfs_filestream.c +++ b/fs/xfs/xfs_filestream.c @@ -83,9 +83,9 @@ xfs_filestream_pick_ag( struct xfs_perag *max_pag = NULL; xfs_extlen_t minlen = *longest; xfs_extlen_t free = 0, minfree, maxfree = 0; - xfs_agnumber_t startag = *agp; - xfs_agnumber_t ag = startag; - int err, trylock, nscan; + xfs_agnumber_t start_agno = *agp; + xfs_agnumber_t agno; + int err, trylock; ASSERT(S_ISDIR(VFS_I(ip)->i_mode)); @@ -97,13 +97,9 @@ xfs_filestream_pick_ag( /* For the first pass, don't sleep trying to init the per-AG. */ trylock = XFS_ALLOC_FLAG_TRYLOCK; - for (nscan = 0; 1; nscan++) { - trace_xfs_filestream_scan(mp, ip->i_ino, ag); - - err = 0; - pag = xfs_perag_grab(mp, ag); - if (!pag) - goto next_ag; +restart: + for_each_perag_wrap(mp, start_agno, agno, pag) { + trace_xfs_filestream_scan(mp, ip->i_ino, agno); *longest = 0; err = xfs_bmap_longest_free_extent(pag, NULL, longest); if (err) { @@ -111,6 +107,7 @@ xfs_filestream_pick_ag( if (err != -EAGAIN) break; /* Couldn't lock the AGF, skip this AG. */ + err = 0; goto next_ag; } @@ -129,77 +126,61 @@ xfs_filestream_pick_ag( * loop, and it guards against two filestreams being established * in the same AG as each other. */ - if (atomic_inc_return(&pag->pagf_fstrms) > 1) { - atomic_dec(&pag->pagf_fstrms); - xfs_perag_rele(pag); - goto next_ag; - } - - if (((minlen && *longest >= minlen) || - (!minlen && pag->pagf_freeblks >= minfree)) && - (!xfs_perag_prefers_metadata(pag) || - !(flags & XFS_PICK_USERDATA) || - (flags & XFS_PICK_LOWSPACE))) { - - /* Break out, retaining the reference on the AG. */ - free = pag->pagf_freeblks; - break; + if (atomic_inc_return(&pag->pagf_fstrms) <= 1) { + if (((minlen && *longest >= minlen) || + (!minlen && pag->pagf_freeblks >= minfree)) && + (!xfs_perag_prefers_metadata(pag) || + !(flags & XFS_PICK_USERDATA) || + (flags & XFS_PICK_LOWSPACE))) { + /* Break out, retaining the reference on the AG. */ + free = pag->pagf_freeblks; + break; + } } /* Drop the reference on this AG, it's not usable. */ atomic_dec(&pag->pagf_fstrms); -next_ag: - /* Move to the next AG, wrapping to AG 0 if necessary. */ - if (++ag >= mp->m_sb.sb_agcount) - ag = 0; + } - /* If a full pass of the AGs hasn't been done yet, continue. */ - if (ag != startag) - continue; + if (err) { + xfs_perag_rele(pag); + if (max_pag) + xfs_perag_rele(max_pag); + return err; + } + if (!pag) { /* Allow sleeping in xfs_alloc_read_agf() on the 2nd pass. */ - if (trylock != 0) { + if (trylock) { trylock = 0; - continue; + goto restart; } /* Finally, if lowspace wasn't set, set it for the 3rd pass. */ if (!(flags & XFS_PICK_LOWSPACE)) { flags |= XFS_PICK_LOWSPACE; - continue; + goto restart; } /* - * Take the AG with the most free space, regardless of whether - * it's already in use by another filestream. + * 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, return NULLAGNUMBER. */ - if (max_pag) { - pag = max_pag; - atomic_inc(&pag->pagf_fstrms); - free = maxfree; - break; + if (!max_pag) { + *agp = NULLAGNUMBER; + trace_xfs_filestream_pick(ip, *agp, free, 0); + return 0; } - - /* take AG 0 if none matched */ - trace_xfs_filestream_pick(ip, *agp, free, nscan); - *agp = 0; - return 0; - } - - trace_xfs_filestream_pick(ip, pag ? pag->pag_agno : NULLAGNUMBER, - free, nscan); - - if (max_pag) + pag = max_pag; + free = maxfree; + atomic_inc(&pag->pagf_fstrms); + } else if (max_pag) { xfs_perag_rele(max_pag); - - if (err) - return err; - - if (!pag) { - *agp = NULLAGNUMBER; - return 0; } + trace_xfs_filestream_pick(ip, pag->pag_agno, free, 0); + err = -ENOMEM; item = kmem_alloc(sizeof(*item), KM_MAYFAIL); if (!item) -- cgit v1.2.3