From 3054face139f9c77566a90a0524dd85c2f38c7f2 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 13 Feb 2023 09:14:55 +1100 Subject: xfs: track an active perag reference in filestreams Rather than just track the agno of the reference, track a referenced perag pointer instead. This will allow active filestreams to prevent AGs from going away until the filestreams have been torn down. Signed-off-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/xfs_filestream.c | 100 +++++++++++++++++++++--------------------------- 1 file changed, 43 insertions(+), 57 deletions(-) (limited to 'fs/xfs') diff --git a/fs/xfs/xfs_filestream.c b/fs/xfs/xfs_filestream.c index 147296a1079e..c92429272ff7 100644 --- a/fs/xfs/xfs_filestream.c +++ b/fs/xfs/xfs_filestream.c @@ -23,7 +23,7 @@ struct xfs_fstrm_item { struct xfs_mru_cache_elem mru; - xfs_agnumber_t ag; /* AG in use for this directory */ + struct xfs_perag *pag; /* AG in use for this directory */ }; enum xfs_fstrm_alloc { @@ -50,43 +50,18 @@ xfs_filestream_peek_ag( return ret; } -static int -xfs_filestream_get_ag( - xfs_mount_t *mp, - xfs_agnumber_t agno) -{ - struct xfs_perag *pag; - int ret; - - pag = xfs_perag_get(mp, agno); - ret = atomic_inc_return(&pag->pagf_fstrms); - xfs_perag_put(pag); - return ret; -} - -static void -xfs_filestream_put_ag( - xfs_mount_t *mp, - xfs_agnumber_t agno) -{ - struct xfs_perag *pag; - - pag = xfs_perag_get(mp, agno); - atomic_dec(&pag->pagf_fstrms); - xfs_perag_put(pag); -} - static void xfs_fstrm_free_func( void *data, struct xfs_mru_cache_elem *mru) { - struct xfs_mount *mp = data; struct xfs_fstrm_item *item = container_of(mru, struct xfs_fstrm_item, mru); + struct xfs_perag *pag = item->pag; - xfs_filestream_put_ag(mp, item->ag); - trace_xfs_filestream_free(mp, mru->key, item->ag); + trace_xfs_filestream_free(pag->pag_mount, mru->key, pag->pag_agno); + atomic_dec(&pag->pagf_fstrms); + xfs_perag_rele(pag); kmem_free(item); } @@ -105,11 +80,11 @@ xfs_filestream_pick_ag( struct xfs_mount *mp = ip->i_mount; struct xfs_fstrm_item *item; struct xfs_perag *pag; + 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; - xfs_agnumber_t max_ag = NULLAGNUMBER; int err, trylock, nscan; ASSERT(S_ISDIR(VFS_I(ip)->i_mode)); @@ -125,13 +100,16 @@ xfs_filestream_pick_ag( for (nscan = 0; 1; nscan++) { trace_xfs_filestream_scan(mp, ip->i_ino, ag); - pag = xfs_perag_get(mp, ag); + err = 0; + pag = xfs_perag_grab(mp, ag); + if (!pag) + goto next_ag; *longest = 0; err = xfs_bmap_longest_free_extent(pag, NULL, longest); if (err) { - xfs_perag_put(pag); + xfs_perag_rele(pag); if (err != -EAGAIN) - return err; + break; /* Couldn't lock the AGF, skip this AG. */ goto next_ag; } @@ -139,7 +117,10 @@ xfs_filestream_pick_ag( /* Keep track of the AG with the most free blocks. */ if (pag->pagf_freeblks > maxfree) { maxfree = pag->pagf_freeblks; - max_ag = ag; + if (max_pag) + xfs_perag_rele(max_pag); + atomic_inc(&pag->pag_active_ref); + max_pag = pag; } /* @@ -148,8 +129,9 @@ xfs_filestream_pick_ag( * loop, and it guards against two filestreams being established * in the same AG as each other. */ - if (xfs_filestream_get_ag(mp, ag) > 1) { - xfs_filestream_put_ag(mp, ag); + if (atomic_inc_return(&pag->pagf_fstrms) > 1) { + atomic_dec(&pag->pagf_fstrms); + xfs_perag_rele(pag); goto next_ag; } @@ -161,15 +143,12 @@ xfs_filestream_pick_ag( /* Break out, retaining the reference on the AG. */ free = pag->pagf_freeblks; - xfs_perag_put(pag); - *agp = ag; break; } /* Drop the reference on this AG, it's not usable. */ - xfs_filestream_put_ag(mp, ag); + atomic_dec(&pag->pagf_fstrms); next_ag: - xfs_perag_put(pag); /* Move to the next AG, wrapping to AG 0 if necessary. */ if (++ag >= mp->m_sb.sb_agcount) ag = 0; @@ -194,10 +173,10 @@ next_ag: * Take the AG with the most free space, regardless of whether * it's already in use by another filestream. */ - if (max_ag != NULLAGNUMBER) { - xfs_filestream_get_ag(mp, max_ag); + if (max_pag) { + pag = max_pag; + atomic_inc(&pag->pagf_fstrms); free = maxfree; - *agp = max_ag; break; } @@ -207,17 +186,26 @@ next_ag: return 0; } - trace_xfs_filestream_pick(ip, *agp, free, nscan); + trace_xfs_filestream_pick(ip, pag ? pag->pag_agno : NULLAGNUMBER, + free, nscan); - if (*agp == NULLAGNUMBER) + if (max_pag) + xfs_perag_rele(max_pag); + + if (err) + return err; + + if (!pag) { + *agp = NULLAGNUMBER; return 0; + } err = -ENOMEM; item = kmem_alloc(sizeof(*item), KM_MAYFAIL); if (!item) goto out_put_ag; - item->ag = *agp; + item->pag = pag; err = xfs_mru_cache_insert(mp->m_filestream, ip->i_ino, &item->mru); if (err) { @@ -226,12 +214,14 @@ next_ag: goto out_free_item; } + *agp = pag->pag_agno; return 0; out_free_item: kmem_free(item); out_put_ag: - xfs_filestream_put_ag(mp, *agp); + atomic_dec(&pag->pagf_fstrms); + xfs_perag_rele(pag); return err; } @@ -284,20 +274,15 @@ xfs_filestream_select_ag_mru( if (!mru) goto out_default_agno; - *agno = container_of(mru, struct xfs_fstrm_item, mru)->ag; + pag = container_of(mru, struct xfs_fstrm_item, mru)->pag; xfs_mru_cache_done(mp->m_filestream); - trace_xfs_filestream_lookup(mp, ap->ip->i_ino, *agno); + trace_xfs_filestream_lookup(mp, ap->ip->i_ino, pag->pag_agno); - ap->blkno = XFS_AGB_TO_FSB(args->mp, *agno, 0); + ap->blkno = XFS_AGB_TO_FSB(args->mp, pag->pag_agno, 0); xfs_bmap_adjacent(ap); - pag = xfs_perag_grab(mp, *agno); - if (!pag) - goto out_default_agno; - error = xfs_bmap_longest_free_extent(pag, args->tp, blen); - xfs_perag_rele(pag); if (error) { if (error != -EAGAIN) return error; @@ -307,6 +292,7 @@ xfs_filestream_select_ag_mru( /* * We are done if there's still enough contiguous free space to succeed. */ + *agno = pag->pag_agno; if (*blen >= args->maxlen) return 0; @@ -315,7 +301,7 @@ xfs_filestream_select_ag_mru( if (mru) { struct xfs_fstrm_item *item = container_of(mru, struct xfs_fstrm_item, mru); - *agno = (item->ag + 1) % mp->m_sb.sb_agcount; + *agno = (item->pag->pag_agno + 1) % mp->m_sb.sb_agcount; xfs_fstrm_free_func(mp, mru); return 0; } -- cgit v1.2.3