[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[Tristan Ye]

Hi Joel,

Following 4 patches are the latest patches series of truncating and punching-holes atop 'merge-window'
branch, with your recent comments being applied.

Tristan.

[Ocfs2-devel] [PATCH 1/4] Ocfs2: Optimize truncting codes for ocfs2 to use ocfs2_remove_btree_range instead.

[Tristan Ye]

As we known, truncate is just a special case of punching holes(from new i_size
to end), we therefore could take advantage of existing ocfs2_remove_btree_range()
codes to reduce the comlexity and redundancy in alloc.c, the goal here is to make
truncate codes more generic and straightforward.

Several former functions only used by ocfs2_commit_truncate() will be simply wiped off.

ocfs2_remove_btree_range() was originally used by punching holes codes, which didn't
take refcount into account(definitely it's a BUG), we therefore need to change that
func a bit to handle refcount treee lock, calculate and reserve block for refcount
tree changes, also decrease refcount at the end, to move these logics in, we needs
to replace the ocfs2_lock_allocators() by adding a new func ocfs2_reserve_blocks_for_rec_trunc()
which accepts some extra blocks to reserve. such changes will not hurt any other codes
who're using ocfs2_remove_btree_range(such as dir truncate and punching holes), actually
punching holes codes do benefit from this.

I merge the following steps into one patch since they may be logically doing one thing,
Though I knew it looks a little bit fat to review.

1). Remove redundant codes used by ocfs2_commit_truncate before, since we're moving to
    ocfs2_remove_btree_range anyway.

2). Add a new func ocfs2_reserve_blocks_for_rec_trunc() for purpose of accepting  some
    extra blocks to reserve.

3). Change ocfs2_prepare_refcount_change_for_del() a bit to fit our needs, it's safe to
    do this since it's only being called by truncating codes.

4). Change ocfs2_remove_btree_range() a bit to take refcount case into account.

5). Finally, we change ocfs2_commit_truncate() to call ocfs2_remove_btree_range() in
    a proper way.

The patch has been tested normally for sanity check, stress tests with heavier workload
will be expected.

Based on this patch, our fixing to punching holes bug will be fairly easy.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
---
 fs/ocfs2/alloc.c        |  685 +++++++++++------------------------------------
 fs/ocfs2/alloc.h        |    8 +-
 fs/ocfs2/dir.c          |    4 +-
 fs/ocfs2/file.c         |   11 +-
 fs/ocfs2/inode.c        |    9 +-
 fs/ocfs2/refcounttree.c |   29 +--
 fs/ocfs2/refcounttree.h |    4 +-
 7 files changed, 178 insertions(+), 572 deletions(-)

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 0cb2945..0cb4248 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -5587,19 +5587,97 @@ out:
 	return ret;
 }
 
+/*
+ * ocfs2_reserve_blocks_for_rec_trunc() would look basically the
+ * same as ocfs2_lock_alloctors(), except for it accepts a blocks
+ * number to reserve some extra blocks, and it only handles meta
+ * data allocations.
+ *
+ * Currently, only ocfs2_remove_btree_range() uses it for truncating
+ * and punching holes.
+ */
+static int ocfs2_reserve_blocks_for_rec_trunc(struct inode *inode,
+					      struct ocfs2_extent_tree *et,
+					      u32 extents_to_split,
+					      struct ocfs2_alloc_context **ac,
+					      int extra_blocks)
+{
+	int ret = 0, num_free_extents;
+	unsigned int max_recs_needed = 2 * extents_to_split;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	*ac = NULL;
+
+	num_free_extents = ocfs2_num_free_extents(osb, et);
+	if (num_free_extents < 0) {
+		ret = num_free_extents;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	if (!num_free_extents ||
+	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
+		extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
+
+	if (extra_blocks) {
+		ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, ac);
+		if (ret < 0) {
+			if (ret != -ENOSPC)
+				mlog_errno(ret);
+			goto out;
+		}
+	}
+
+out:
+	if (ret) {
+		if (*ac) {
+			ocfs2_free_alloc_context(*ac);
+			*ac = NULL;
+		}
+	}
+
+	return ret;
+}
+
 int ocfs2_remove_btree_range(struct inode *inode,
 			     struct ocfs2_extent_tree *et,
-			     u32 cpos, u32 phys_cpos, u32 len,
-			     struct ocfs2_cached_dealloc_ctxt *dealloc)
+			     u32 cpos, u32 phys_cpos, u32 len, int flags,
+			     struct ocfs2_cached_dealloc_ctxt *dealloc,
+			     u64 refcount_loc)
 {
-	int ret;
+	int ret, credits = 0, extra_blocks = 0;
 	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	struct inode *tl_inode = osb->osb_tl_inode;
 	handle_t *handle;
 	struct ocfs2_alloc_context *meta_ac = NULL;
+	struct ocfs2_refcount_tree *ref_tree = NULL;
+
+	if ((flags & OCFS2_EXT_REFCOUNTED) && len) {
+		BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
+			 OCFS2_HAS_REFCOUNT_FL));
+
+		ret = ocfs2_lock_refcount_tree(osb, refcount_loc, 1,
+					       &ref_tree, NULL);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		ret = ocfs2_prepare_refcount_change_for_del(inode,
+							    refcount_loc,
+							    phys_blkno,
+							    len,
+							    &credits,
+							    &extra_blocks);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+	}
 
-	ret = ocfs2_lock_allocators(inode, et, 0, 1, NULL, &meta_ac);
+	ret = ocfs2_reserve_blocks_for_rec_trunc(inode, et, 1, &meta_ac,
+						 extra_blocks);
 	if (ret) {
 		mlog_errno(ret);
 		return ret;
@@ -5615,7 +5693,8 @@ int ocfs2_remove_btree_range(struct inode *inode,
 		}
 	}
 
-	handle = ocfs2_start_trans(osb, ocfs2_remove_extent_credits(osb->sb));
+	handle = ocfs2_start_trans(osb,
+			ocfs2_remove_extent_credits(osb->sb) + credits);
 	if (IS_ERR(handle)) {
 		ret = PTR_ERR(handle);
 		mlog_errno(ret);
@@ -5642,9 +5721,20 @@ int ocfs2_remove_btree_range(struct inode *inode,
 
 	ocfs2_journal_dirty(handle, et->et_root_bh);
 
-	ret = ocfs2_truncate_log_append(osb, handle, phys_blkno, len);
-	if (ret)
-		mlog_errno(ret);
+	if (phys_blkno) {
+		if (flags & OCFS2_EXT_REFCOUNTED)
+			ret = ocfs2_decrease_refcount(inode, handle,
+					ocfs2_blocks_to_clusters(osb->sb,
+								 phys_blkno),
+					len, meta_ac,
+					dealloc, 1);
+		else
+			ret = ocfs2_truncate_log_append(osb, handle,
+							phys_blkno, len);
+		if (ret)
+			mlog_errno(ret);
+
+	}
 
 out_commit:
 	ocfs2_commit_trans(osb, handle);
@@ -5654,6 +5744,9 @@ out:
 	if (meta_ac)
 		ocfs2_free_alloc_context(meta_ac);
 
+	if (ref_tree)
+		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+
 	return ret;
 }
 
@@ -6481,417 +6574,6 @@ static int ocfs2_cache_extent_block_free(struct ocfs2_cached_dealloc_ctxt *ctxt,
 					 le16_to_cpu(eb->h_suballoc_bit));
 }
 
-/* This function will figure out whether the currently last extent
- * block will be deleted, and if it will, what the new last extent
- * block will be so we can update his h_next_leaf_blk field, as well
- * as the dinodes i_last_eb_blk */
-static int ocfs2_find_new_last_ext_blk(struct inode *inode,
-				       unsigned int clusters_to_del,
-				       struct ocfs2_path *path,
-				       struct buffer_head **new_last_eb)
-{
-	int next_free, ret = 0;
-	u32 cpos;
-	struct ocfs2_extent_rec *rec;
-	struct ocfs2_extent_block *eb;
-	struct ocfs2_extent_list *el;
-	struct buffer_head *bh = NULL;
-
-	*new_last_eb = NULL;
-
-	/* we have no tree, so of course, no last_eb. */
-	if (!path->p_tree_depth)
-		goto out;
-
-	/* trunc to zero special case - this makes tree_depth = 0
-	 * regardless of what it is.  */
-	if (OCFS2_I(inode)->ip_clusters == clusters_to_del)
-		goto out;
-
-	el = path_leaf_el(path);
-	BUG_ON(!el->l_next_free_rec);
-
-	/*
-	 * Make sure that this extent list will actually be empty
-	 * after we clear away the data. We can shortcut out if
-	 * there's more than one non-empty extent in the
-	 * list. Otherwise, a check of the remaining extent is
-	 * necessary.
-	 */
-	next_free = le16_to_cpu(el->l_next_free_rec);
-	rec = NULL;
-	if (ocfs2_is_empty_extent(&el->l_recs[0])) {
-		if (next_free > 2)
-			goto out;
-
-		/* We may have a valid extent in index 1, check it. */
-		if (next_free == 2)
-			rec = &el->l_recs[1];
-
-		/*
-		 * Fall through - no more nonempty extents, so we want
-		 * to delete this leaf.
-		 */
-	} else {
-		if (next_free > 1)
-			goto out;
-
-		rec = &el->l_recs[0];
-	}
-
-	if (rec) {
-		/*
-		 * Check it we'll only be trimming off the end of this
-		 * cluster.
-		 */
-		if (le16_to_cpu(rec->e_leaf_clusters) > clusters_to_del)
-			goto out;
-	}
-
-	ret = ocfs2_find_cpos_for_left_leaf(inode->i_sb, path, &cpos);
-	if (ret) {
-		mlog_errno(ret);
-		goto out;
-	}
-
-	ret = ocfs2_find_leaf(INODE_CACHE(inode), path_root_el(path), cpos, &bh);
-	if (ret) {
-		mlog_errno(ret);
-		goto out;
-	}
-
-	eb = (struct ocfs2_extent_block *) bh->b_data;
-	el = &eb->h_list;
-
-	/* ocfs2_find_leaf() gets the eb from ocfs2_read_extent_block().
-	 * Any corruption is a code bug. */
-	BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));
-
-	*new_last_eb = bh;
-	get_bh(*new_last_eb);
-	mlog(0, "returning block %llu, (cpos: %u)\n",
-	     (unsigned long long)le64_to_cpu(eb->h_blkno), cpos);
-out:
-	brelse(bh);
-
-	return ret;
-}
-
-/*
- * Trim some clusters off the rightmost edge of a tree. Only called
- * during truncate.
- *
- * The caller needs to:
- *   - start journaling of each path component.
- *   - compute and fully set up any new last ext block
- */
-static int ocfs2_trim_tree(struct inode *inode, struct ocfs2_path *path,
-			   handle_t *handle, struct ocfs2_truncate_context *tc,
-			   u32 clusters_to_del, u64 *delete_start, u8 *flags)
-{
-	int ret, i, index = path->p_tree_depth;
-	u32 new_edge = 0;
-	u64 deleted_eb = 0;
-	struct buffer_head *bh;
-	struct ocfs2_extent_list *el;
-	struct ocfs2_extent_rec *rec;
-
-	*delete_start = 0;
-	*flags = 0;
-
-	while (index >= 0) {
-		bh = path->p_node[index].bh;
-		el = path->p_node[index].el;
-
-		mlog(0, "traveling tree (index = %d, block = %llu)\n",
-		     index,  (unsigned long long)bh->b_blocknr);
-
-		BUG_ON(le16_to_cpu(el->l_next_free_rec) == 0);
-
-		if (index !=
-		    (path->p_tree_depth - le16_to_cpu(el->l_tree_depth))) {
-			ocfs2_error(inode->i_sb,
-				    "Inode %lu has invalid ext. block %llu",
-				    inode->i_ino,
-				    (unsigned long long)bh->b_blocknr);
-			ret = -EROFS;
-			goto out;
-		}
-
-find_tail_record:
-		i = le16_to_cpu(el->l_next_free_rec) - 1;
-		rec = &el->l_recs[i];
-
-		mlog(0, "Extent list before: record %d: (%u, %u, %llu), "
-		     "next = %u\n", i, le32_to_cpu(rec->e_cpos),
-		     ocfs2_rec_clusters(el, rec),
-		     (unsigned long long)le64_to_cpu(rec->e_blkno),
-		     le16_to_cpu(el->l_next_free_rec));
-
-		BUG_ON(ocfs2_rec_clusters(el, rec) < clusters_to_del);
-
-		if (le16_to_cpu(el->l_tree_depth) == 0) {
-			/*
-			 * If the leaf block contains a single empty
-			 * extent and no records, we can just remove
-			 * the block.
-			 */
-			if (i == 0 && ocfs2_is_empty_extent(rec)) {
-				memset(rec, 0,
-				       sizeof(struct ocfs2_extent_rec));
-				el->l_next_free_rec = cpu_to_le16(0);
-
-				goto delete;
-			}
-
-			/*
-			 * Remove any empty extents by shifting things
-			 * left. That should make life much easier on
-			 * the code below. This condition is rare
-			 * enough that we shouldn't see a performance
-			 * hit.
-			 */
-			if (ocfs2_is_empty_extent(&el->l_recs[0])) {
-				le16_add_cpu(&el->l_next_free_rec, -1);
-
-				for(i = 0;
-				    i < le16_to_cpu(el->l_next_free_rec); i++)
-					el->l_recs[i] = el->l_recs[i + 1];
-
-				memset(&el->l_recs[i], 0,
-				       sizeof(struct ocfs2_extent_rec));
-
-				/*
-				 * We've modified our extent list. The
-				 * simplest way to handle this change
-				 * is to being the search from the
-				 * start again.
-				 */
-				goto find_tail_record;
-			}
-
-			le16_add_cpu(&rec->e_leaf_clusters, -clusters_to_del);
-
-			/*
-			 * We'll use "new_edge" on our way back up the
-			 * tree to know what our rightmost cpos is.
-			 */
-			new_edge = le16_to_cpu(rec->e_leaf_clusters);
-			new_edge += le32_to_cpu(rec->e_cpos);
-
-			/*
-			 * The caller will use this to delete data blocks.
-			 */
-			*delete_start = le64_to_cpu(rec->e_blkno)
-				+ ocfs2_clusters_to_blocks(inode->i_sb,
-					le16_to_cpu(rec->e_leaf_clusters));
-			*flags = rec->e_flags;
-
-			/*
-			 * If it's now empty, remove this record.
-			 */
-			if (le16_to_cpu(rec->e_leaf_clusters) == 0) {
-				memset(rec, 0,
-				       sizeof(struct ocfs2_extent_rec));
-				le16_add_cpu(&el->l_next_free_rec, -1);
-			}
-		} else {
-			if (le64_to_cpu(rec->e_blkno) == deleted_eb) {
-				memset(rec, 0,
-				       sizeof(struct ocfs2_extent_rec));
-				le16_add_cpu(&el->l_next_free_rec, -1);
-
-				goto delete;
-			}
-
-			/* Can this actually happen? */
-			if (le16_to_cpu(el->l_next_free_rec) == 0)
-				goto delete;
-
-			/*
-			 * We never actually deleted any clusters
-			 * because our leaf was empty. There's no
-			 * reason to adjust the rightmost edge then.
-			 */
-			if (new_edge == 0)
-				goto delete;
-
-			rec->e_int_clusters = cpu_to_le32(new_edge);
-			le32_add_cpu(&rec->e_int_clusters,
-				     -le32_to_cpu(rec->e_cpos));
-
-			 /*
-			  * A deleted child record should have been
-			  * caught above.
-			  */
-			 BUG_ON(le32_to_cpu(rec->e_int_clusters) == 0);
-		}
-
-delete:
-		ocfs2_journal_dirty(handle, bh);
-
-		mlog(0, "extent list container %llu, after: record %d: "
-		     "(%u, %u, %llu), next = %u.\n",
-		     (unsigned long long)bh->b_blocknr, i,
-		     le32_to_cpu(rec->e_cpos), ocfs2_rec_clusters(el, rec),
-		     (unsigned long long)le64_to_cpu(rec->e_blkno),
-		     le16_to_cpu(el->l_next_free_rec));
-
-		/*
-		 * We must be careful to only attempt delete of an
-		 * extent block (and not the root inode block).
-		 */
-		if (index > 0 && le16_to_cpu(el->l_next_free_rec) == 0) {
-			struct ocfs2_extent_block *eb =
-				(struct ocfs2_extent_block *)bh->b_data;
-
-			/*
-			 * Save this for use when processing the
-			 * parent block.
-			 */
-			deleted_eb = le64_to_cpu(eb->h_blkno);
-
-			mlog(0, "deleting this extent block.\n");
-
-			ocfs2_remove_from_cache(INODE_CACHE(inode), bh);
-
-			BUG_ON(ocfs2_rec_clusters(el, &el->l_recs[0]));
-			BUG_ON(le32_to_cpu(el->l_recs[0].e_cpos));
-			BUG_ON(le64_to_cpu(el->l_recs[0].e_blkno));
-
-			ret = ocfs2_cache_extent_block_free(&tc->tc_dealloc, eb);
-			/* An error here is not fatal. */
-			if (ret < 0)
-				mlog_errno(ret);
-		} else {
-			deleted_eb = 0;
-		}
-
-		index--;
-	}
-
-	ret = 0;
-out:
-	return ret;
-}
-
-static int ocfs2_do_truncate(struct ocfs2_super *osb,
-			     unsigned int clusters_to_del,
-			     struct inode *inode,
-			     struct buffer_head *fe_bh,
-			     handle_t *handle,
-			     struct ocfs2_truncate_context *tc,
-			     struct ocfs2_path *path,
-			     struct ocfs2_alloc_context *meta_ac)
-{
-	int status;
-	struct ocfs2_dinode *fe;
-	struct ocfs2_extent_block *last_eb = NULL;
-	struct ocfs2_extent_list *el;
-	struct buffer_head *last_eb_bh = NULL;
-	u64 delete_blk = 0;
-	u8 rec_flags;
-
-	fe = (struct ocfs2_dinode *) fe_bh->b_data;
-
-	status = ocfs2_find_new_last_ext_blk(inode, clusters_to_del,
-					     path, &last_eb_bh);
-	if (status < 0) {
-		mlog_errno(status);
-		goto bail;
-	}
-
-	/*
-	 * Each component will be touched, so we might as well journal
-	 * here to avoid having to handle errors later.
-	 */
-	status = ocfs2_journal_access_path(INODE_CACHE(inode), handle, path);
-	if (status < 0) {
-		mlog_errno(status);
-		goto bail;
-	}
-
-	if (last_eb_bh) {
-		status = ocfs2_journal_access_eb(handle, INODE_CACHE(inode), last_eb_bh,
-						 OCFS2_JOURNAL_ACCESS_WRITE);
-		if (status < 0) {
-			mlog_errno(status);
-			goto bail;
-		}
-
-		last_eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
-	}
-
-	el = &(fe->id2.i_list);
-
-	/*
-	 * Lower levels depend on this never happening, but it's best
-	 * to check it up here before changing the tree.
-	 */
-	if (el->l_tree_depth && el->l_recs[0].e_int_clusters == 0) {
-		ocfs2_error(inode->i_sb,
-			    "Inode %lu has an empty extent record, depth %u\n",
-			    inode->i_ino, le16_to_cpu(el->l_tree_depth));
-		status = -EROFS;
-		goto bail;
-	}
-
-	dquot_free_space_nodirty(inode,
-			ocfs2_clusters_to_bytes(osb->sb, clusters_to_del));
-	spin_lock(&OCFS2_I(inode)->ip_lock);
-	OCFS2_I(inode)->ip_clusters = le32_to_cpu(fe->i_clusters) -
-				      clusters_to_del;
-	spin_unlock(&OCFS2_I(inode)->ip_lock);
-	le32_add_cpu(&fe->i_clusters, -clusters_to_del);
-	inode->i_blocks = ocfs2_inode_sector_count(inode);
-
-	status = ocfs2_trim_tree(inode, path, handle, tc,
-				 clusters_to_del, &delete_blk, &rec_flags);
-	if (status) {
-		mlog_errno(status);
-		goto bail;
-	}
-
-	if (le32_to_cpu(fe->i_clusters) == 0) {
-		/* trunc to zero is a special case. */
-		el->l_tree_depth = 0;
-		fe->i_last_eb_blk = 0;
-	} else if (last_eb)
-		fe->i_last_eb_blk = last_eb->h_blkno;
-
-	ocfs2_journal_dirty(handle, fe_bh);
-
-	if (last_eb) {
-		/* If there will be a new last extent block, then by
-		 * definition, there cannot be any leaves to the right of
-		 * him. */
-		last_eb->h_next_leaf_blk = 0;
-		ocfs2_journal_dirty(handle, last_eb_bh);
-	}
-
-	if (delete_blk) {
-		if (rec_flags & OCFS2_EXT_REFCOUNTED)
-			status = ocfs2_decrease_refcount(inode, handle,
-					ocfs2_blocks_to_clusters(osb->sb,
-								 delete_blk),
-					clusters_to_del, meta_ac,
-					&tc->tc_dealloc, 1);
-		else
-			status = ocfs2_truncate_log_append(osb, handle,
-							   delete_blk,
-							   clusters_to_del);
-		if (status < 0) {
-			mlog_errno(status);
-			goto bail;
-		}
-	}
-	status = 0;
-bail:
-	brelse(last_eb_bh);
-	mlog_exit(status);
-	return status;
-}
-
 static int ocfs2_zero_func(handle_t *handle, struct buffer_head *bh)
 {
 	set_buffer_uptodate(bh);
@@ -7300,26 +6982,29 @@ out:
  */
 int ocfs2_commit_truncate(struct ocfs2_super *osb,
 			  struct inode *inode,
-			  struct buffer_head *fe_bh,
-			  struct ocfs2_truncate_context *tc)
+			  struct buffer_head *di_bh)
 {
-	int status, i, credits, tl_sem = 0;
-	u32 clusters_to_del, new_highest_cpos, range;
+	int status = 0, i, flags = 0;
+	u32 new_highest_cpos, range, trunc_cpos, trunc_len, phys_cpos, coff;
 	u64 blkno = 0;
 	struct ocfs2_extent_list *el;
-	handle_t *handle = NULL;
-	struct inode *tl_inode = osb->osb_tl_inode;
+	struct ocfs2_extent_rec *rec;
 	struct ocfs2_path *path = NULL;
-	struct ocfs2_dinode *di = (struct ocfs2_dinode *)fe_bh->b_data;
-	struct ocfs2_alloc_context *meta_ac = NULL;
-	struct ocfs2_refcount_tree *ref_tree = NULL;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_extent_list *root_el = &(di->id2.i_list);
+	u64 refcount_loc = le64_to_cpu(di->i_refcount_loc);
+	struct ocfs2_extent_tree et;
+	struct ocfs2_cached_dealloc_ctxt dealloc;
 
 	mlog_entry_void();
 
+	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
+	ocfs2_init_dealloc_ctxt(&dealloc);
+
 	new_highest_cpos = ocfs2_clusters_for_bytes(osb->sb,
 						     i_size_read(inode));
 
-	path = ocfs2_new_path(fe_bh, &di->id2.i_list,
+	path = ocfs2_new_path(di_bh, &di->id2.i_list,
 			      ocfs2_journal_access_di);
 	if (!path) {
 		status = -ENOMEM;
@@ -7338,8 +7023,6 @@ start:
 		goto bail;
 	}
 
-	credits = 0;
-
 	/*
 	 * Truncate always works against the rightmost tree branch.
 	 */
@@ -7374,101 +7057,62 @@ start:
 	}
 
 	i = le16_to_cpu(el->l_next_free_rec) - 1;
-	range = le32_to_cpu(el->l_recs[i].e_cpos) +
-		ocfs2_rec_clusters(el, &el->l_recs[i]);
-	if (i == 0 && ocfs2_is_empty_extent(&el->l_recs[i])) {
-		clusters_to_del = 0;
-	} else if (le32_to_cpu(el->l_recs[i].e_cpos) >= new_highest_cpos) {
-		clusters_to_del = ocfs2_rec_clusters(el, &el->l_recs[i]);
-		blkno = le64_to_cpu(el->l_recs[i].e_blkno);
+	rec = &el->l_recs[i];
+	flags = rec->e_flags;
+	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
+
+	if (i == 0 && ocfs2_is_empty_extent(rec)) {
+		/*
+		 * Lower levels depend on this never happening, but it's best
+		 * to check it up here before changing the tree.
+		*/
+		if (root_el->l_tree_depth && rec->e_int_clusters == 0) {
+			ocfs2_error(inode->i_sb, "Inode %lu has an empty "
+				    "extent record, depth %u\n", inode->i_ino,
+				    le16_to_cpu(root_el->l_tree_depth));
+			status = -EROFS;
+			goto bail;
+		}
+		trunc_cpos = le32_to_cpu(rec->e_cpos);
+		trunc_len = 0;
+		blkno = 0;
+	} else if (le32_to_cpu(rec->e_cpos) >= new_highest_cpos) {
+		/*
+		 * Truncate entire record.
+		 */
+		trunc_cpos = le32_to_cpu(rec->e_cpos);
+		trunc_len = ocfs2_rec_clusters(el, rec);
+		blkno = le64_to_cpu(rec->e_blkno);
 	} else if (range > new_highest_cpos) {
-		clusters_to_del = (ocfs2_rec_clusters(el, &el->l_recs[i]) +
-				   le32_to_cpu(el->l_recs[i].e_cpos)) -
-				  new_highest_cpos;
-		blkno = le64_to_cpu(el->l_recs[i].e_blkno) +
-			ocfs2_clusters_to_blocks(inode->i_sb,
-				ocfs2_rec_clusters(el, &el->l_recs[i]) -
-				clusters_to_del);
+		/*
+		 * Partial truncate. it also should be
+		 * the last truncate we're doing.
+		 */
+		trunc_cpos = new_highest_cpos;
+		trunc_len = range - new_highest_cpos;
+		coff = new_highest_cpos - le32_to_cpu(rec->e_cpos);
+		blkno = le64_to_cpu(rec->e_blkno) +
+				ocfs2_clusters_to_blocks(inode->i_sb, coff);
 	} else {
+		/*
+		 * Truncate completed, leave happily.
+		 */
 		status = 0;
 		goto bail;
 	}
 
-	mlog(0, "clusters_to_del = %u in this pass, tail blk=%llu\n",
-	     clusters_to_del, (unsigned long long)path_leaf_bh(path)->b_blocknr);
-
-	if (el->l_recs[i].e_flags & OCFS2_EXT_REFCOUNTED && clusters_to_del) {
-		BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
-			 OCFS2_HAS_REFCOUNT_FL));
-
-		status = ocfs2_lock_refcount_tree(osb,
-						le64_to_cpu(di->i_refcount_loc),
-						1, &ref_tree, NULL);
-		if (status) {
-			mlog_errno(status);
-			goto bail;
-		}
-
-		status = ocfs2_prepare_refcount_change_for_del(inode, fe_bh,
-							       blkno,
-							       clusters_to_del,
-							       &credits,
-							       &meta_ac);
-		if (status < 0) {
-			mlog_errno(status);
-			goto bail;
-		}
-	}
-
-	mutex_lock(&tl_inode->i_mutex);
-	tl_sem = 1;
-	/* ocfs2_truncate_log_needs_flush guarantees us at least one
-	 * record is free for use. If there isn't any, we flush to get
-	 * an empty truncate log.  */
-	if (ocfs2_truncate_log_needs_flush(osb)) {
-		status = __ocfs2_flush_truncate_log(osb);
-		if (status < 0) {
-			mlog_errno(status);
-			goto bail;
-		}
-	}
-
-	credits += ocfs2_calc_tree_trunc_credits(osb->sb, clusters_to_del,
-						(struct ocfs2_dinode *)fe_bh->b_data,
-						el);
-	handle = ocfs2_start_trans(osb, credits);
-	if (IS_ERR(handle)) {
-		status = PTR_ERR(handle);
-		handle = NULL;
-		mlog_errno(status);
-		goto bail;
-	}
+	phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
 
-	status = ocfs2_do_truncate(osb, clusters_to_del, inode, fe_bh, handle,
-				   tc, path, meta_ac);
+	status = ocfs2_remove_btree_range(inode, &et, trunc_cpos,
+					  phys_cpos, trunc_len, flags, &dealloc,
+					  refcount_loc);
 	if (status < 0) {
 		mlog_errno(status);
 		goto bail;
 	}
 
-	mutex_unlock(&tl_inode->i_mutex);
-	tl_sem = 0;
-
-	ocfs2_commit_trans(osb, handle);
-	handle = NULL;
-
 	ocfs2_reinit_path(path, 1);
 
-	if (meta_ac) {
-		ocfs2_free_alloc_context(meta_ac);
-		meta_ac = NULL;
-	}
-
-	if (ref_tree) {
-		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
-		ref_tree = NULL;
-	}
-
 	/*
 	 * The check above will catch the case where we've truncated
 	 * away all allocation.
@@ -7479,25 +7123,10 @@ bail:
 
 	ocfs2_schedule_truncate_log_flush(osb, 1);
 
-	if (tl_sem)
-		mutex_unlock(&tl_inode->i_mutex);
-
-	if (handle)
-		ocfs2_commit_trans(osb, handle);
-
-	if (meta_ac)
-		ocfs2_free_alloc_context(meta_ac);
-
-	if (ref_tree)
-		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
-
-	ocfs2_run_deallocs(osb, &tc->tc_dealloc);
+	ocfs2_run_deallocs(osb, &dealloc);
 
 	ocfs2_free_path(path);
 
-	/* This will drop the ext_alloc cluster lock for us */
-	ocfs2_free_truncate_context(tc);
-
 	mlog_exit(status);
 	return status;
 }
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 1db4359..4fb9882 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -140,8 +140,9 @@ int ocfs2_remove_extent(handle_t *handle, struct ocfs2_extent_tree *et,
 			struct ocfs2_cached_dealloc_ctxt *dealloc);
 int ocfs2_remove_btree_range(struct inode *inode,
 			     struct ocfs2_extent_tree *et,
-			     u32 cpos, u32 phys_cpos, u32 len,
-			     struct ocfs2_cached_dealloc_ctxt *dealloc);
+			     u32 cpos, u32 phys_cpos, u32 len, int flags,
+			     struct ocfs2_cached_dealloc_ctxt *dealloc,
+			     u64 refcount_loc);
 
 int ocfs2_num_free_extents(struct ocfs2_super *osb,
 			   struct ocfs2_extent_tree *et);
@@ -233,8 +234,7 @@ int ocfs2_prepare_truncate(struct ocfs2_super *osb,
 			   struct ocfs2_truncate_context **tc);
 int ocfs2_commit_truncate(struct ocfs2_super *osb,
 			  struct inode *inode,
-			  struct buffer_head *fe_bh,
-			  struct ocfs2_truncate_context *tc);
+			  struct buffer_head *di_bh);
 int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh,
 			  unsigned int start, unsigned int end, int trunc);
 
diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
index 6c9a28a..4a75c2e 100644
--- a/fs/ocfs2/dir.c
+++ b/fs/ocfs2/dir.c
@@ -4526,8 +4526,8 @@ int ocfs2_dx_dir_truncate(struct inode *dir, struct buffer_head *di_bh)
 
 		p_cpos = ocfs2_blocks_to_clusters(dir->i_sb, blkno);
 
-		ret = ocfs2_remove_btree_range(dir, &et, cpos, p_cpos, clen,
-					       &dealloc);
+		ret = ocfs2_remove_btree_range(dir, &et, cpos, p_cpos, clen, 0,
+					       &dealloc, 0);
 		if (ret) {
 			mlog_errno(ret);
 			goto out;
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 19d16f2..4c7a4d8 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -444,7 +444,6 @@ static int ocfs2_truncate_file(struct inode *inode,
 	int status = 0;
 	struct ocfs2_dinode *fe = NULL;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
-	struct ocfs2_truncate_context *tc = NULL;
 
 	mlog_entry("(inode = %llu, new_i_size = %llu\n",
 		   (unsigned long long)OCFS2_I(inode)->ip_blkno,
@@ -515,13 +514,7 @@ static int ocfs2_truncate_file(struct inode *inode,
 		goto bail_unlock_sem;
 	}
 
-	status = ocfs2_prepare_truncate(osb, inode, di_bh, &tc);
-	if (status < 0) {
-		mlog_errno(status);
-		goto bail_unlock_sem;
-	}
-
-	status = ocfs2_commit_truncate(osb, inode, di_bh, tc);
+	status = ocfs2_commit_truncate(osb, inode, di_bh);
 	if (status < 0) {
 		mlog_errno(status);
 		goto bail_unlock_sem;
@@ -1494,7 +1487,7 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 		if (phys_cpos != 0) {
 			ret = ocfs2_remove_btree_range(inode, &et, cpos,
 						       phys_cpos, alloc_size,
-						       &dealloc);
+						       0, &dealloc, 0);
 			if (ret) {
 				mlog_errno(ret);
 				goto out;
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 9ee13f7..053765c 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -544,7 +544,6 @@ static int ocfs2_truncate_for_delete(struct ocfs2_super *osb,
 				     struct buffer_head *fe_bh)
 {
 	int status = 0;
-	struct ocfs2_truncate_context *tc = NULL;
 	struct ocfs2_dinode *fe;
 	handle_t *handle = NULL;
 
@@ -586,13 +585,7 @@ static int ocfs2_truncate_for_delete(struct ocfs2_super *osb,
 		ocfs2_commit_trans(osb, handle);
 		handle = NULL;
 
-		status = ocfs2_prepare_truncate(osb, inode, fe_bh, &tc);
-		if (status < 0) {
-			mlog_errno(status);
-			goto out;
-		}
-
-		status = ocfs2_commit_truncate(osb, inode, fe_bh, tc);
+		status = ocfs2_commit_truncate(osb, inode, fe_bh);
 		if (status < 0) {
 			mlog_errno(status);
 			goto out;
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 33dd2a1..6fab289 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -2509,20 +2509,19 @@ out:
  *
  * Normally the refcount blocks store these refcount should be
  * contiguous also, so that we can get the number easily.
- * As for meta_ac, we will at most add split 2 refcount record and
- * 2 more refcount block, so just check it in a rough way.
+ * We will@most add split 2 refcount records and 2 more
+ * refcount blocks, so just check it in a rough way.
  *
  * Caller must hold refcount tree lock.
  */
 int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
-					  struct buffer_head *di_bh,
+					  u64 refcount_loc,
 					  u64 phys_blkno,
 					  u32 clusters,
 					  int *credits,
-					  struct ocfs2_alloc_context **meta_ac)
+					  int *ref_blocks)
 {
-	int ret, ref_blocks = 0;
-	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	int ret;
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
 	struct buffer_head *ref_root_bh = NULL;
 	struct ocfs2_refcount_tree *tree;
@@ -2539,14 +2538,13 @@ int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
 	BUG_ON(!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL));
 
 	ret = ocfs2_get_refcount_tree(OCFS2_SB(inode->i_sb),
-				      le64_to_cpu(di->i_refcount_loc), &tree);
+				      refcount_loc, &tree);
 	if (ret) {
 		mlog_errno(ret);
 		goto out;
 	}
 
-	ret = ocfs2_read_refcount_block(&tree->rf_ci,
-					le64_to_cpu(di->i_refcount_loc),
+	ret = ocfs2_read_refcount_block(&tree->rf_ci, refcount_loc,
 					&ref_root_bh);
 	if (ret) {
 		mlog_errno(ret);
@@ -2557,21 +2555,14 @@ int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
 					       &tree->rf_ci,
 					       ref_root_bh,
 					       start_cpos, clusters,
-					       &ref_blocks, credits);
+					       ref_blocks, credits);
 	if (ret) {
 		mlog_errno(ret);
 		goto out;
 	}
 
-	mlog(0, "reserve new metadata %d, credits = %d\n",
-	     ref_blocks, *credits);
-
-	if (ref_blocks) {
-		ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(inode->i_sb),
-							ref_blocks, meta_ac);
-		if (ret)
-			mlog_errno(ret);
-	}
+	mlog(0, "reserve new metadata %d blocks, credits = %d\n",
+	     *ref_blocks, *credits);
 
 out:
 	brelse(ref_root_bh);
diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h
index c1d19b1..9983ba1 100644
--- a/fs/ocfs2/refcounttree.h
+++ b/fs/ocfs2/refcounttree.h
@@ -47,11 +47,11 @@ int ocfs2_decrease_refcount(struct inode *inode,
 			    struct ocfs2_cached_dealloc_ctxt *dealloc,
 			    int delete);
 int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
-					  struct buffer_head *di_bh,
+					  u64 refcount_loc,
 					  u64 phys_blkno,
 					  u32 clusters,
 					  int *credits,
-					  struct ocfs2_alloc_context **meta_ac);
+					  int *ref_blocks);
 int ocfs2_refcount_cow(struct inode *inode, struct buffer_head *di_bh,
 		       u32 cpos, u32 write_len, u32 max_cpos);
 
-- 
1.5.5

[Ocfs2-devel] [PATCH 2/4] Ocfs2: Fix punching hole codes to correctly do CoW during cluster zeroing.

[Tristan Ye]

Based on the former patch of truncating optimization, bugfix for refcount on
punching holes can be fairly easy and straightforward since most of work we
should take into account for refcounting have been completed already in func
ocfs2_remove_btree_range(), which is also being used by our truncating codes.

The patch just did CoW for reflinks when a hole is being punched whose start
and end offset were within one cluster, which means partial zeroing for a cluster
will be performed soon.

The patch has been tested fixing the following bug:

http://oss.oracle.com/bugzilla/show_bug.cgi?id=1216

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
---
 fs/ocfs2/file.c |   30 +++++++++++++++++++++++++++---
 1 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 4c7a4d8..3346e5b 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1422,12 +1422,14 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 				    struct buffer_head *di_bh, u64 byte_start,
 				    u64 byte_len)
 {
-	int ret = 0;
+	int ret = 0, flags = 0;
 	u32 trunc_start, trunc_len, cpos, phys_cpos, alloc_size;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	struct ocfs2_cached_dealloc_ctxt dealloc;
 	struct address_space *mapping = inode->i_mapping;
 	struct ocfs2_extent_tree et;
+	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	u64 refcount_loc = le64_to_cpu(di->i_refcount_loc);
 
 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
 	ocfs2_init_dealloc_ctxt(&dealloc);
@@ -1453,6 +1455,27 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 		goto out;
 	}
 
+	/*
+	 * For reflinks, we may need to CoW 2 clusters which might be
+	 * partially zero'd later, if hole's start and end offset were
+	 * within one cluster(means is not exactly aligned to clustersize).
+	 */
+
+	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL) {
+
+		ret = ocfs2_cow_file_pos(inode, di_bh, byte_start);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		ret = ocfs2_cow_file_pos(inode, di_bh, byte_start + byte_len);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+	}
+
 	trunc_start = ocfs2_clusters_for_bytes(osb->sb, byte_start);
 	trunc_len = (byte_start + byte_len) >> osb->s_clustersize_bits;
 	if (trunc_len >= trunc_start)
@@ -1474,7 +1497,7 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 	cpos = trunc_start;
 	while (trunc_len) {
 		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos,
-					 &alloc_size, NULL);
+					 &alloc_size, &flags);
 		if (ret) {
 			mlog_errno(ret);
 			goto out;
@@ -1487,7 +1510,8 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 		if (phys_cpos != 0) {
 			ret = ocfs2_remove_btree_range(inode, &et, cpos,
 						       phys_cpos, alloc_size,
-						       0, &dealloc, 0);
+						       flags, &dealloc,
+						       refcount_loc);
 			if (ret) {
 				mlog_errno(ret);
 				goto out;
-- 
1.5.5

[Ocfs2-devel] [PATCH 3/4] Ocfs2: Make ocfs2_find_cpos_for_left_leaf() public.

[Tristan Ye]

The original idea to pull ocfs2_find_cpos_for_left_leaf() out of
alloc.c is to benefit punching-holes optimization patch, it however,
can also be referred by other funcs in the future who want to do the
same job.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
---
 fs/ocfs2/alloc.c |    4 ++--
 fs/ocfs2/alloc.h |    2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 0cb4248..7e9cb75 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -2209,8 +2209,8 @@ out:
  *
  * Will return zero if the path passed in is already the leftmost path.
  */
-static int ocfs2_find_cpos_for_left_leaf(struct super_block *sb,
-					 struct ocfs2_path *path, u32 *cpos)
+int ocfs2_find_cpos_for_left_leaf(struct super_block *sb,
+				  struct ocfs2_path *path, u32 *cpos)
 {
 	int i, j, ret = 0;
 	u64 blkno;
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 4fb9882..a55a27b 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -319,6 +319,8 @@ int ocfs2_journal_access_path(struct ocfs2_caching_info *ci,
 			      struct ocfs2_path *path);
 int ocfs2_find_cpos_for_right_leaf(struct super_block *sb,
 				   struct ocfs2_path *path, u32 *cpos);
+int ocfs2_find_cpos_for_left_leaf(struct super_block *sb,
+				  struct ocfs2_path *path, u32 *cpos);
 int ocfs2_find_subtree_root(struct ocfs2_extent_tree *et,
 			    struct ocfs2_path *left,
 			    struct ocfs2_path *right);
-- 
1.5.5

[Ocfs2-devel] [PATCH 4/4] Ocfs2: Optimize punching-hole codes v5.

[Tristan Ye]

V5 patch simplifies the logic of handling existing holes and procedures
for skipping extent blocks, and removed most of confusing comments.

V5 patch has survived with fill_verify_holes testcase in ocfs2-test,
it also passed my manual sanity check and stress tests with enormous
extent records.

Currently punching hole on a file with 3+ extent tree depth was
really a performance disaster, it even caused several hours to
go, though we may not hit this in real life with such a huge extent
number.

One simple way to improve the performance is quite straightforward,
by learning the logic of truncating codes, means we'd punch hole from
hole_end to hole_start, which reduce the overhead of btree operation
in a significant way, such as tree rotation and moving.

Following is the testing result when punching hole from 0 to file end
in bytes, on a 1G file, 1G file consists of 256k extent records, each record
cover 4k data(just one cluster, clustersize is 4k):

===========================================================================
 * Former punching-hole mechanism:
===========================================================================

   I waited 1 hour for its completion, unfortunately it's still ongoing.

===========================================================================
 * Patched punching-hode mechanism:
===========================================================================

   real 0m2.518s
   user 0m0.000s
   sys  0m2.445s

That means we've gained up to 1000 times improvement on performance in this
case, whee! It's fairly cool. and it looks like that performance gain will
be raising when extent records grow.

The patch was based on my former 2 patches, which were about truncating
codes optimization and fixup to handle CoW on punching hole.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
---
 fs/ocfs2/file.c |  164 +++++++++++++++++++++++++++++++++++++++++++++++--------
 1 files changed, 140 insertions(+), 24 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 3346e5b..9c1047c 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1418,18 +1418,90 @@ out:
 	return ret;
 }
 
+static int ocfs2_find_rec(struct ocfs2_extent_list *el, u32 pos)
+{
+	int i;
+	struct ocfs2_extent_rec *rec = NULL;
+
+	for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
+
+		rec = &el->l_recs[i];
+
+		if (le32_to_cpu(rec->e_cpos) < pos)
+			break;
+	}
+
+	return i;
+}
+
+/*
+ * Helper to calculate the punching pos and length in one run, we handle the
+ * following three cases in order:
+ *
+ * - remove the entire record
+ * - remove a partial record
+ * - no record needs to be removed (hole-punching completed)
+*/
+static void ocfs2_calc_trunc_pos(struct inode *inode,
+				 struct ocfs2_extent_list *el,
+				 struct ocfs2_extent_rec *rec,
+				 u32 trunc_start, u32 *trunc_cpos,
+				 u32 *trunc_len, u32 *trunc_end,
+				 u64 *blkno, int *done)
+{
+	int ret = 0;
+	u32 coff, range;
+
+	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
+
+	if (le32_to_cpu(rec->e_cpos) >= trunc_start) {
+		*trunc_cpos = le32_to_cpu(rec->e_cpos);
+		/*
+		 * Skip holes if any.
+		 */
+		if (range < *trunc_end)
+			*trunc_end = range;
+		*trunc_len = *trunc_end - le32_to_cpu(rec->e_cpos);
+		*blkno = le64_to_cpu(rec->e_blkno);
+		*trunc_end = le32_to_cpu(rec->e_cpos);
+	} else if (range > trunc_start) {
+		*trunc_cpos = trunc_start;
+		*trunc_len = *trunc_end - trunc_start;
+		coff = trunc_start - le32_to_cpu(rec->e_cpos);
+		*blkno = le64_to_cpu(rec->e_blkno) +
+				ocfs2_clusters_to_blocks(inode->i_sb, coff);
+		*trunc_end = trunc_start;
+	} else {
+		/*
+		 * It may have two following possibilities:
+		 *
+		 * - last record has been removed
+		 * - trunc_start was within a hole
+		 *
+		 * both two cases mean the completion of hole punching.
+		 */
+		ret = 1;
+	}
+
+	*done = ret;
+}
+
 static int ocfs2_remove_inode_range(struct inode *inode,
 				    struct buffer_head *di_bh, u64 byte_start,
 				    u64 byte_len)
 {
-	int ret = 0, flags = 0;
-	u32 trunc_start, trunc_len, cpos, phys_cpos, alloc_size;
+	int ret = 0, flags = 0, done = 0, i;
+	u32 trunc_start, trunc_len, trunc_end, trunc_cpos, phys_cpos;
+	u32 cluster_in_el;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	struct ocfs2_cached_dealloc_ctxt dealloc;
 	struct address_space *mapping = inode->i_mapping;
 	struct ocfs2_extent_tree et;
+	struct ocfs2_path *path = NULL;
+	struct ocfs2_extent_list *el = NULL;
+	struct ocfs2_extent_rec *rec = NULL;
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
-	u64 refcount_loc = le64_to_cpu(di->i_refcount_loc);
+	u64 blkno, refcount_loc = le64_to_cpu(di->i_refcount_loc);
 
 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
 	ocfs2_init_dealloc_ctxt(&dealloc);
@@ -1477,16 +1549,13 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 	}
 
 	trunc_start = ocfs2_clusters_for_bytes(osb->sb, byte_start);
-	trunc_len = (byte_start + byte_len) >> osb->s_clustersize_bits;
-	if (trunc_len >= trunc_start)
-		trunc_len -= trunc_start;
-	else
-		trunc_len = 0;
+	trunc_end = (byte_start + byte_len) >> osb->s_clustersize_bits;
+	cluster_in_el = trunc_end;
 
-	mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u\n",
+	mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, cend: %u\n",
 	     (unsigned long long)OCFS2_I(inode)->ip_blkno,
 	     (unsigned long long)byte_start,
-	     (unsigned long long)byte_len, trunc_start, trunc_len);
+	     (unsigned long long)byte_len, trunc_start, trunc_end);
 
 	ret = ocfs2_zero_partial_clusters(inode, byte_start, byte_len);
 	if (ret) {
@@ -1494,32 +1563,79 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 		goto out;
 	}
 
-	cpos = trunc_start;
-	while (trunc_len) {
-		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos,
-					 &alloc_size, &flags);
+	path = ocfs2_new_path_from_et(&et);
+	if (!path) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	while (trunc_end > trunc_start) {
+
+		ret = ocfs2_find_path(INODE_CACHE(inode), path,
+				      cluster_in_el);
 		if (ret) {
 			mlog_errno(ret);
 			goto out;
 		}
 
-		if (alloc_size > trunc_len)
-			alloc_size = trunc_len;
+		el = path_leaf_el(path);
+
+		i = ocfs2_find_rec(el, trunc_end);
+		/*
+		 * Need to go to previous extent block.
+		 */
+		if (i < 0) {
+			if (path->p_tree_depth == 0)
+				break;
 
-		/* Only do work for non-holes */
-		if (phys_cpos != 0) {
-			ret = ocfs2_remove_btree_range(inode, &et, cpos,
-						       phys_cpos, alloc_size,
-						       flags, &dealloc,
-						       refcount_loc);
+			ret = ocfs2_find_cpos_for_left_leaf(inode->i_sb,
+							    path,
+							    &cluster_in_el);
 			if (ret) {
 				mlog_errno(ret);
 				goto out;
 			}
+
+			/*
+			 * We've reached the leftmost extent block,
+			 * it's safe to leave.
+			 */
+			if (cluster_in_el == 0)
+				break;
+
+			/*
+			 * The 'pos' searched for previous extent block is
+			 * always one cluster less than actual trunc_end.
+			 */
+			trunc_end = cluster_in_el + 1;
+
+			ocfs2_reinit_path(path, 1);
+
+			continue;
+
+		} else
+			rec = &el->l_recs[i];
+
+		ocfs2_calc_trunc_pos(inode, el, rec, trunc_start, &trunc_cpos,
+				     &trunc_len, &trunc_end, &blkno, &done);
+		if (done)
+			break;
+
+		flags = rec->e_flags;
+		phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
+
+		ret = ocfs2_remove_btree_range(inode, &et, trunc_cpos,
+					       phys_cpos, trunc_len, flags,
+					       &dealloc, refcount_loc);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
 		}
 
-		cpos += alloc_size;
-		trunc_len -= alloc_size;
+		cluster_in_el = trunc_end;
+
+		ocfs2_reinit_path(path, 1);
 	}
 
 	ocfs2_truncate_cluster_pages(inode, byte_start, byte_len);
-- 
1.5.5

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[tristan]

All,

Whoops!! Sorry for polluting your mailbox by sending three identical 
patches series at one day.

At the very beginning, 'sendmail' thread in my coding box was actually 
blocked somehow,
and I didn't notice that, what's worse, I made another 2 attempts, still 
blocked, after I reboot
the coding box, all blocked mail get sent...

Joel,

Pick up one of three patches series, they're fairly identical...


Tristan.


Tristan Ye wrote:
> Hi Joel,
>
> Following 4 patches are the latest patches series of truncating and punching-holes atop 'merge-window'
> branch, with your recent comments being applied.
>
> Tristan.
>
>
>
> _______________________________________________
> Ocfs2-devel mailing list
> Ocfs2-devel at oss.oracle.com
> http://oss.oracle.com/mailman/listinfo/ocfs2-devel
>   

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[Joel Becker]

On Tue, May 11, 2010 at 05:54:41PM +0800, Tristan Ye wrote:
> Hi Joel,
> 
> Following 4 patches are the latest patches series of truncating and punching-holes atop 'merge-window'
> branch, with your recent comments being applied.

	These look good.  Waiting on Mark's ack.

Joel

-- 

Life's Little Instruction Book #157 

	"Take time to smell the roses."

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127

[Ocfs2-devel] [PATCH 1/4] Ocfs2: Optimize truncting codes for ocfs2 to use ocfs2_remove_btree_range instead.

[Mark Fasheh]

On Tue, May 11, 2010 at 05:54:42PM +0800, Tristan Ye wrote:
> As we known, truncate is just a special case of punching holes(from new i_size
> to end), we therefore could take advantage of existing ocfs2_remove_btree_range()
> codes to reduce the comlexity and redundancy in alloc.c, the goal here is to make
> truncate codes more generic and straightforward.
> 
> Several former functions only used by ocfs2_commit_truncate() will be simply wiped off.
> 
> ocfs2_remove_btree_range() was originally used by punching holes codes, which didn't
> take refcount into account(definitely it's a BUG), we therefore need to change that
> func a bit to handle refcount treee lock, calculate and reserve block for refcount
> tree changes, also decrease refcount at the end, to move these logics in, we needs
> to replace the ocfs2_lock_allocators() by adding a new func ocfs2_reserve_blocks_for_rec_trunc()
> which accepts some extra blocks to reserve. such changes will not hurt any other codes
> who're using ocfs2_remove_btree_range(such as dir truncate and punching holes), actually
> punching holes codes do benefit from this.
> 
> I merge the following steps into one patch since they may be logically doing one thing,
> Though I knew it looks a little bit fat to review.
> 
> 1). Remove redundant codes used by ocfs2_commit_truncate before, since we're moving to
>     ocfs2_remove_btree_range anyway.
> 
> 2). Add a new func ocfs2_reserve_blocks_for_rec_trunc() for purpose of accepting  some
>     extra blocks to reserve.
> 
> 3). Change ocfs2_prepare_refcount_change_for_del() a bit to fit our needs, it's safe to
>     do this since it's only being called by truncating codes.
> 
> 4). Change ocfs2_remove_btree_range() a bit to take refcount case into account.
> 
> 5). Finally, we change ocfs2_commit_truncate() to call ocfs2_remove_btree_range() in
>     a proper way.
> 
> The patch has been tested normally for sanity check, stress tests with heavier workload
> will be expected.
> 
> Based on this patch, our fixing to punching holes bug will be fairly easy.
> 
> Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
> ---
>  fs/ocfs2/alloc.c        |  685 +++++++++++------------------------------------

Excellent - that's a lot of redundant code we get to remove  :) Thanks
Tristan for taking this on!


>  fs/ocfs2/alloc.h        |    8 +-
>  fs/ocfs2/dir.c          |    4 +-
>  fs/ocfs2/file.c         |   11 +-
>  fs/ocfs2/inode.c        |    9 +-
>  fs/ocfs2/refcounttree.c |   29 +--
>  fs/ocfs2/refcounttree.h |    4 +-
>  7 files changed, 178 insertions(+), 572 deletions(-)
> 
> diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
> index 0cb2945..0cb4248 100644
> --- a/fs/ocfs2/alloc.c
> +++ b/fs/ocfs2/alloc.c
> @@ -5587,19 +5587,97 @@ out:
>  	return ret;
>  }
>  
> +/*
> + * ocfs2_reserve_blocks_for_rec_trunc() would look basically the
> + * same as ocfs2_lock_alloctors(), except for it accepts a blocks
> + * number to reserve some extra blocks, and it only handles meta
> + * data allocations.
> + *
> + * Currently, only ocfs2_remove_btree_range() uses it for truncating
> + * and punching holes.
> + */
> +static int ocfs2_reserve_blocks_for_rec_trunc(struct inode *inode,
> +					      struct ocfs2_extent_tree *et,
> +					      u32 extents_to_split,
> +					      struct ocfs2_alloc_context **ac,
> +					      int extra_blocks)
> +{
> +	int ret = 0, num_free_extents;
> +	unsigned int max_recs_needed = 2 * extents_to_split;
> +	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
> +
> +	*ac = NULL;
> +
> +	num_free_extents = ocfs2_num_free_extents(osb, et);
> +	if (num_free_extents < 0) {
> +		ret = num_free_extents;
> +		mlog_errno(ret);
> +		goto out;
> +	}
> +
> +	if (!num_free_extents ||
> +	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
> +		extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
> +
> +	if (extra_blocks) {
> +		ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, ac);
> +		if (ret < 0) {
> +			if (ret != -ENOSPC)
> +				mlog_errno(ret);

This means we could possibly -ENOSPC while trying to truncate a reflinked
file (to free space perhaps). This problem is out of the scope of your patch
so I'm not asking you to fix it here, but it seems worth noting.



Rest of the patch looks good. The testing results are promising too.

Silly question - did you test that a 'punch hole' for the entire range of a
file produces a result identical to that of truncating the file to zero size?


Acked-by: Mark Fasheh <mfasheh@suse.com>
	--Mark

--
Mark Fasheh

[Ocfs2-devel] [PATCH 2/4] Ocfs2: Fix punching hole codes to correctly do CoW during cluster zeroing.

[Mark Fasheh]

On Tue, May 11, 2010 at 05:54:43PM +0800, Tristan Ye wrote:
> Based on the former patch of truncating optimization, bugfix for refcount on
> punching holes can be fairly easy and straightforward since most of work we
> should take into account for refcounting have been completed already in func
> ocfs2_remove_btree_range(), which is also being used by our truncating codes.
> 
> The patch just did CoW for reflinks when a hole is being punched whose start
> and end offset were within one cluster, which means partial zeroing for a cluster
> will be performed soon.
> 
> The patch has been tested fixing the following bug:
> 
> http://oss.oracle.com/bugzilla/show_bug.cgi?id=1216
> 
> Signed-off-by: Tristan Ye <tristan.ye@oracle.com>

Acked-by: Mark Fasheh <mfasheh@suse.com>
	--Mark

--
Mark Fasheh

[Ocfs2-devel] [PATCH 3/4] Ocfs2: Make ocfs2_find_cpos_for_left_leaf() public.

[Mark Fasheh]

On Tue, May 11, 2010 at 05:54:44PM +0800, Tristan Ye wrote:
> The original idea to pull ocfs2_find_cpos_for_left_leaf() out of
> alloc.c is to benefit punching-holes optimization patch, it however,
> can also be referred by other funcs in the future who want to do the
> same job.
> 
> Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
Acked-by: Mark Fasheh <mfasheh@suse.com>
	--Mark

--
Mark Fasheh

[Ocfs2-devel] [PATCH 4/4] Ocfs2: Optimize punching-hole codes v5.

[Mark Fasheh]

On Tue, May 11, 2010 at 05:54:45PM +0800, Tristan Ye wrote:
> V5 patch simplifies the logic of handling existing holes and procedures
> for skipping extent blocks, and removed most of confusing comments.
> 
> V5 patch has survived with fill_verify_holes testcase in ocfs2-test,
> it also passed my manual sanity check and stress tests with enormous
> extent records.

Ok, this looks good too.


> Currently punching hole on a file with 3+ extent tree depth was
> really a performance disaster, it even caused several hours to
> go, though we may not hit this in real life with such a huge extent
> number.
> 
> One simple way to improve the performance is quite straightforward,
> by learning the logic of truncating codes, means we'd punch hole from
> hole_end to hole_start, which reduce the overhead of btree operation
> in a significant way, such as tree rotation and moving.

Right, so by punching from right to left, we're optimizing away rotations
for at least those calls which are asking for a hole at the tail of the
file. What is the performance change if we consider the other cases
(punching in the middle or beginning of a file) only?


Code-wise everything looks sane. I won't lie - it helps me to be comfortable
the changes knowing that you tested regularly with our tools  ;)

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
	--Mark

--
Mark Fasheh

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[Joel Becker]

On Tue, May 11, 2010 at 01:40:55PM -0700, Joel Becker wrote:
> On Tue, May 11, 2010 at 05:54:41PM +0800, Tristan Ye wrote:
> > Hi Joel,
> > 
> > Following 4 patches are the latest patches series of truncating and punching-holes atop 'merge-window'
> > branch, with your recent comments being applied.
> 
> 	These look good.  Waiting on Mark's ack.

	These patches are now in the merge-window branch of ocfs2.git.
I have cleaned up the patch descriptions a little.

Joel

-- 

"If you are ever in doubt as to whether or not to kiss a pretty girl, 
 give her the benefit of the doubt"
                                        -Thomas Carlyle

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127

[Ocfs2-devel] [PATCH 1/4] Ocfs2: Optimize truncting codes for ocfs2 to use ocfs2_remove_btree_range instead.

[tristan]

Hi Mark,

Thanks for the review:-)


Mark Fasheh wrote:
> On Tue, May 11, 2010 at 05:54:42PM +0800, Tristan Ye wrote:
>> As we known, truncate is just a special case of punching holes(from new i_size
>> to end), we therefore could take advantage of existing ocfs2_remove_btree_range()
>> codes to reduce the comlexity and redundancy in alloc.c, the goal here is to make
>> truncate codes more generic and straightforward.
>>
>> Several former functions only used by ocfs2_commit_truncate() will be simply wiped off.
>>
>> ocfs2_remove_btree_range() was originally used by punching holes codes, which didn't
>> take refcount into account(definitely it's a BUG), we therefore need to change that
>> func a bit to handle refcount treee lock, calculate and reserve block for refcount
>> tree changes, also decrease refcount at the end, to move these logics in, we needs
>> to replace the ocfs2_lock_allocators() by adding a new func ocfs2_reserve_blocks_for_rec_trunc()
>> which accepts some extra blocks to reserve. such changes will not hurt any other codes
>> who're using ocfs2_remove_btree_range(such as dir truncate and punching holes), actually
>> punching holes codes do benefit from this.
>>
>> I merge the following steps into one patch since they may be logically doing one thing,
>> Though I knew it looks a little bit fat to review.
>>
>> 1). Remove redundant codes used by ocfs2_commit_truncate before, since we're moving to
>>     ocfs2_remove_btree_range anyway.
>>
>> 2). Add a new func ocfs2_reserve_blocks_for_rec_trunc() for purpose of accepting  some
>>     extra blocks to reserve.
>>
>> 3). Change ocfs2_prepare_refcount_change_for_del() a bit to fit our needs, it's safe to
>>     do this since it's only being called by truncating codes.
>>
>> 4). Change ocfs2_remove_btree_range() a bit to take refcount case into account.
>>
>> 5). Finally, we change ocfs2_commit_truncate() to call ocfs2_remove_btree_range() in
>>     a proper way.
>>
>> The patch has been tested normally for sanity check, stress tests with heavier workload
>> will be expected.
>>
>> Based on this patch, our fixing to punching holes bug will be fairly easy.
>>
>> Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
>> ---
>>  fs/ocfs2/alloc.c        |  685 +++++++++++------------------------------------
>
> Excellent - that's a lot of redundant code we get to remove  :) Thanks
> Tristan for taking this on!
>
>
>>  fs/ocfs2/alloc.h        |    8 +-
>>  fs/ocfs2/dir.c          |    4 +-
>>  fs/ocfs2/file.c         |   11 +-
>>  fs/ocfs2/inode.c        |    9 +-
>>  fs/ocfs2/refcounttree.c |   29 +--
>>  fs/ocfs2/refcounttree.h |    4 +-
>>  7 files changed, 178 insertions(+), 572 deletions(-)
>>
>> diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
>> index 0cb2945..0cb4248 100644
>> --- a/fs/ocfs2/alloc.c
>> +++ b/fs/ocfs2/alloc.c
>> @@ -5587,19 +5587,97 @@ out:
>>  	return ret;
>>  }
>>  
>> +/*
>> + * ocfs2_reserve_blocks_for_rec_trunc() would look basically the
>> + * same as ocfs2_lock_alloctors(), except for it accepts a blocks
>> + * number to reserve some extra blocks, and it only handles meta
>> + * data allocations.
>> + *
>> + * Currently, only ocfs2_remove_btree_range() uses it for truncating
>> + * and punching holes.
>> + */
>> +static int ocfs2_reserve_blocks_for_rec_trunc(struct inode *inode,
>> +					      struct ocfs2_extent_tree *et,
>> +					      u32 extents_to_split,
>> +					      struct ocfs2_alloc_context **ac,
>> +					      int extra_blocks)
>> +{
>> +	int ret = 0, num_free_extents;
>> +	unsigned int max_recs_needed = 2 * extents_to_split;
>> +	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
>> +
>> +	*ac = NULL;
>> +
>> +	num_free_extents = ocfs2_num_free_extents(osb, et);
>> +	if (num_free_extents < 0) {
>> +		ret = num_free_extents;
>> +		mlog_errno(ret);
>> +		goto out;
>> +	}
>> +
>> +	if (!num_free_extents ||
>> +	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
>> +		extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
>> +
>> +	if (extra_blocks) {
>> +		ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, ac);
>> +		if (ret < 0) {
>> +			if (ret != -ENOSPC)
>> +				mlog_errno(ret);
>
> This means we could possibly -ENOSPC while trying to truncate a reflinked
> file (to free space perhaps). This problem is out of the scope of your patch
> so I'm not asking you to fix it here, but it seems worth noting.

Look at former code piece:

/* Always lock for any unwritten extents - we might want to
* add blocks during a split.
*/
if (!num_free_extents ||
(ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
}

It also has the possibility to meet -ENOSPC.

Tao,

Do we really have to free space in that case when being failed to ask 
blocks for refcounting stuffs.

>
>
>
> Rest of the patch looks good. The testing results are promising too.
>
> Silly question - did you test that a 'punch hole' for the entire range of a
> file produces a result identical to that of truncating the file to zero size?

I've tested this for sure:-), they're totally the same except for 
punching-hole change
nothing on i_size.


>
>
> Acked-by: Mark Fasheh <mfasheh@suse.com>
> 	--Mark
>
> --
> Mark Fasheh

[Ocfs2-devel] [PATCH 4/4] Ocfs2: Optimize punching-hole codes v5.

[tristan]

Mark Fasheh wrote:
> On Tue, May 11, 2010 at 05:54:45PM +0800, Tristan Ye wrote:
>> V5 patch simplifies the logic of handling existing holes and procedures
>> for skipping extent blocks, and removed most of confusing comments.
>>
>> V5 patch has survived with fill_verify_holes testcase in ocfs2-test,
>> it also passed my manual sanity check and stress tests with enormous
>> extent records.
>
> Ok, this looks good too.
>
>
>> Currently punching hole on a file with 3+ extent tree depth was
>> really a performance disaster, it even caused several hours to
>> go, though we may not hit this in real life with such a huge extent
>> number.
>>
>> One simple way to improve the performance is quite straightforward,
>> by learning the logic of truncating codes, means we'd punch hole from
>> hole_end to hole_start, which reduce the overhead of btree operation
>> in a significant way, such as tree rotation and moving.
>
> Right, so by punching from right to left, we're optimizing away rotations
> for at least those calls which are asking for a hole at the tail of the
> file. What is the performance change if we consider the other cases
> (punching in the middle or beginning of a file) only?

Mark,

Let me show you my latest benchmark statistics, say we're going to 
operate on a 1G file, with 1G/4k extent recs(clustersize = 4k, each 
cluster takes a ext record):

1. punching hole from begin to end:
# time ./punch_hole -f /storage/testfile -s 0 -l 1073741824

================ statistics with v5 patch =================
real 0m0.856s
user 0m0.000s
sys 0m0.855s
=========================== end ===========================

=============== statistics without v5 patch ===============
real 0m16.545s
user 0m0.001s
sys 0m15.704s
=========================== end ===========================

2. punching hole from begin to middle:
# time ./punch_hole -f /storage/testfile -s 0 -l 536870912

================ statistics with v5 patch =================
real 0m8.004s
user 0m0.000s
sys 0m7.960s
=========================== end ===========================

=============== statistics without v5 patch ===============
real 0m11.808s
user 0m0.000s
sys 0m11.786s
=========================== end ===========================

3. punching hole from middle to end:
./punch_hole -f /storage/testfile -s 536870912 -l 536870912

================ statistics with v5 patch =================
real 0m0.433s
user 0m0.000s
sys 0m0.433s
=========================== end ===========================

=============== statistics without v5 patch ===============
real 0m4.255s
user 0m0.000s
sys 0m4.249s
=========================== end ===========================


Patches are going to pay off when number of extent records was large 
enough, and its performance gain increases sharply as extent record grows.

>
>
> Code-wise everything looks sane. I won't lie - it helps me to be comfortable
> the changes knowing that you tested regularly with our tools  ;)

Definitely, regular testcases in ocfs2-test.git all have been tried out, 
besides, with a combined test with reflink.

What's more, many boundary and manual testcases also get passed on my 
hand as I can imagine.

>
> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
> 	--Mark
>
> --
> Mark Fasheh

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[Tristan Ye]

Hi Joel,

Following 4 patches are the latest patches series of truncating and punching-holes atop 'merge-window'
branch, with your recent comments being applied.

Tristan.

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[Tristan Ye]

Hi Joel,

Following 4 patches are the latest patches series of truncating and punching-holes
atop 'merge-window' branch, with your recent comments being applied.

Tristan.

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[tristan]

Joel Becker wrote:
> On Thu, May 06, 2010 at 03:04:48PM +0800, tristan wrote:
>> Following 4 patches are the entire patches series of truncating and 
>> punching-holes atop your latest merge-window branch.
>>
>> And it survived all my testcases on hand.
>
> Tristan,
> 	Thank you for sending the new series.  It looks good
> functionally.  I replied to the first patch with a couple of cleanups.

All cleanups make sense!

> 	Please use the --compose option to git-send-email to create your
> [PATCH 0/x] emails.  This makes them thread in our mailboxes better ;-)
Joel,


Thank you for teaching me this, it really helps, I usually hand-edit the 
[patch 0/x] before;-(


> 	Mark, can I get your evaluation of this patch series before I
> push it to merge-window?
>
> Joel
>

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[Joel Becker]

On Thu, May 06, 2010 at 03:04:48PM +0800, tristan wrote:
> Following 4 patches are the entire patches series of truncating and 
> punching-holes atop your latest merge-window branch.
> 
> And it survived all my testcases on hand.

Tristan,
	Thank you for sending the new series.  It looks good
functionally.  I replied to the first patch with a couple of cleanups.
	Please use the --compose option to git-send-email to create your
[PATCH 0/x] emails.  This makes them thread in our mailboxes better ;-)
	Mark, can I get your evaluation of this patch series before I
push it to merge-window?

Joel

-- 

"You don't make the poor richer by making the rich poorer."
	- Sir Winston Churchill

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127

[Ocfs2-devel] [PATCH 0/4] Patches series for optimization of truncating and punching-hole.

[tristan]

Hi Joel,

Following 4 patches are the entire patches series of truncating and 
punching-holes atop your latest merge-window branch.

And it survived all my testcases on hand.


Tristan.