From 510a28e195cd7260ccd089109d61ae3b9938a21e Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Thu, 16 Sep 2021 12:19:00 -0700 Subject: xfs: don't allocate scrub contexts on the stack Convert the on-stack scrub context, btree scrub context, and da btree scrub context into a heap allocation so that we reduce stack usage and gain the ability to handle tall btrees without issue. Specifically, this saves us ~208 bytes for the dabtree scrub, ~464 bytes for the btree scrub, and ~200 bytes for the main scrub context. Signed-off-by: Darrick J. Wong Reviewed-by: Chandan Babu R Reviewed-by: Christoph Hellwig --- fs/xfs/scrub/dabtree.c | 62 +++++++++++++++++++++++++++----------------------- 1 file changed, 33 insertions(+), 29 deletions(-) (limited to 'fs/xfs/scrub/dabtree.c') diff --git a/fs/xfs/scrub/dabtree.c b/fs/xfs/scrub/dabtree.c index 8a52514bc1ff..b962cfbbd92b 100644 --- a/fs/xfs/scrub/dabtree.c +++ b/fs/xfs/scrub/dabtree.c @@ -473,7 +473,7 @@ xchk_da_btree( xchk_da_btree_rec_fn scrub_fn, void *private) { - struct xchk_da_btree ds = {}; + struct xchk_da_btree *ds; struct xfs_mount *mp = sc->mp; struct xfs_da_state_blk *blks; struct xfs_da_node_entry *key; @@ -486,32 +486,35 @@ xchk_da_btree( return 0; /* Set up initial da state. */ - ds.dargs.dp = sc->ip; - ds.dargs.whichfork = whichfork; - ds.dargs.trans = sc->tp; - ds.dargs.op_flags = XFS_DA_OP_OKNOENT; - ds.state = xfs_da_state_alloc(&ds.dargs); - ds.sc = sc; - ds.private = private; + ds = kmem_zalloc(sizeof(struct xchk_da_btree), KM_NOFS | KM_MAYFAIL); + if (!ds) + return -ENOMEM; + ds->dargs.dp = sc->ip; + ds->dargs.whichfork = whichfork; + ds->dargs.trans = sc->tp; + ds->dargs.op_flags = XFS_DA_OP_OKNOENT; + ds->state = xfs_da_state_alloc(&ds->dargs); + ds->sc = sc; + ds->private = private; if (whichfork == XFS_ATTR_FORK) { - ds.dargs.geo = mp->m_attr_geo; - ds.lowest = 0; - ds.highest = 0; + ds->dargs.geo = mp->m_attr_geo; + ds->lowest = 0; + ds->highest = 0; } else { - ds.dargs.geo = mp->m_dir_geo; - ds.lowest = ds.dargs.geo->leafblk; - ds.highest = ds.dargs.geo->freeblk; + ds->dargs.geo = mp->m_dir_geo; + ds->lowest = ds->dargs.geo->leafblk; + ds->highest = ds->dargs.geo->freeblk; } - blkno = ds.lowest; + blkno = ds->lowest; level = 0; /* Find the root of the da tree, if present. */ - blks = ds.state->path.blk; - error = xchk_da_btree_block(&ds, level, blkno); + blks = ds->state->path.blk; + error = xchk_da_btree_block(ds, level, blkno); if (error) goto out_state; /* - * We didn't find a block at ds.lowest, which means that there's + * We didn't find a block at ds->lowest, which means that there's * no LEAF1/LEAFN tree (at least not where it's supposed to be), * so jump out now. */ @@ -523,16 +526,16 @@ xchk_da_btree( /* Handle leaf block. */ if (blks[level].magic != XFS_DA_NODE_MAGIC) { /* End of leaf, pop back towards the root. */ - if (blks[level].index >= ds.maxrecs[level]) { + if (blks[level].index >= ds->maxrecs[level]) { if (level > 0) blks[level - 1].index++; - ds.tree_level++; + ds->tree_level++; level--; continue; } /* Dispatch record scrubbing. */ - error = scrub_fn(&ds, level); + error = scrub_fn(ds, level); if (error) break; if (xchk_should_terminate(sc, &error) || @@ -545,17 +548,17 @@ xchk_da_btree( /* End of node, pop back towards the root. */ - if (blks[level].index >= ds.maxrecs[level]) { + if (blks[level].index >= ds->maxrecs[level]) { if (level > 0) blks[level - 1].index++; - ds.tree_level++; + ds->tree_level++; level--; continue; } /* Hashes in order for scrub? */ - key = xchk_da_btree_node_entry(&ds, level); - error = xchk_da_btree_hash(&ds, level, &key->hashval); + key = xchk_da_btree_node_entry(ds, level); + error = xchk_da_btree_hash(ds, level, &key->hashval); if (error) goto out; @@ -564,11 +567,11 @@ xchk_da_btree( level++; if (level >= XFS_DA_NODE_MAXDEPTH) { /* Too deep! */ - xchk_da_set_corrupt(&ds, level - 1); + xchk_da_set_corrupt(ds, level - 1); break; } - ds.tree_level--; - error = xchk_da_btree_block(&ds, level, blkno); + ds->tree_level--; + error = xchk_da_btree_block(ds, level, blkno); if (error) goto out; if (blks[level].bp == NULL) @@ -587,6 +590,7 @@ out: } out_state: - xfs_da_state_free(ds.state); + xfs_da_state_free(ds->state); + kmem_free(ds); return error; } -- cgit v1.2.3