* [PATCH v2 1/3] mm: add filemap_fdatawait_range_keep_errors()
2019-06-20 15:18 [PATCH v2 0/3] Add dirty range scoping to jbd2 Ross Zwisler
@ 2019-06-20 15:18 ` Ross Zwisler
2019-06-20 15:18 ` [PATCH v2 2/3] jbd2: introduce jbd2_inode dirty range scoping Ross Zwisler
2019-06-20 15:18 ` [PATCH v2 3/3] ext4: use " Ross Zwisler
2 siblings, 0 replies; 9+ messages in thread
From: Ross Zwisler @ 2019-06-20 15:18 UTC (permalink / raw)
To: linux-kernel
Cc: Ross Zwisler, Theodore Ts'o, Alexander Viro, Andreas Dilger,
Jan Kara, linux-ext4, linux-fsdevel, linux-mm, Fletcher Woodruff,
Justin TerAvest, Jan Kara, stable
In the spirit of filemap_fdatawait_range() and
filemap_fdatawait_keep_errors(), introduce
filemap_fdatawait_range_keep_errors() which both takes a range upon
which to wait and does not clear errors from the address space.
Signed-off-by: Ross Zwisler <zwisler@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
---
include/linux/fs.h | 2 ++
mm/filemap.c | 22 ++++++++++++++++++++++
2 files changed, 24 insertions(+)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f7fdfe93e25d3..79fec8a8413f4 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2712,6 +2712,8 @@ extern int filemap_flush(struct address_space *);
extern int filemap_fdatawait_keep_errors(struct address_space *mapping);
extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
loff_t lend);
+extern int filemap_fdatawait_range_keep_errors(struct address_space *mapping,
+ loff_t start_byte, loff_t end_byte);
static inline int filemap_fdatawait(struct address_space *mapping)
{
diff --git a/mm/filemap.c b/mm/filemap.c
index df2006ba0cfa5..e87252ca0835a 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -553,6 +553,28 @@ int filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte,
}
EXPORT_SYMBOL(filemap_fdatawait_range);
+/**
+ * filemap_fdatawait_range_keep_errors - wait for writeback to complete
+ * @mapping: address space structure to wait for
+ * @start_byte: offset in bytes where the range starts
+ * @end_byte: offset in bytes where the range ends (inclusive)
+ *
+ * Walk the list of under-writeback pages of the given address space in the
+ * given range and wait for all of them. Unlike filemap_fdatawait_range(),
+ * this function does not clear error status of the address space.
+ *
+ * Use this function if callers don't handle errors themselves. Expected
+ * call sites are system-wide / filesystem-wide data flushers: e.g. sync(2),
+ * fsfreeze(8)
+ */
+int filemap_fdatawait_range_keep_errors(struct address_space *mapping,
+ loff_t start_byte, loff_t end_byte)
+{
+ __filemap_fdatawait_range(mapping, start_byte, end_byte);
+ return filemap_check_and_keep_errors(mapping);
+}
+EXPORT_SYMBOL(filemap_fdatawait_range_keep_errors);
+
/**
* file_fdatawait_range - wait for writeback to complete
* @file: file pointing to address space structure to wait for
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v2 2/3] jbd2: introduce jbd2_inode dirty range scoping
2019-06-20 15:18 [PATCH v2 0/3] Add dirty range scoping to jbd2 Ross Zwisler
2019-06-20 15:18 ` [PATCH v2 1/3] mm: add filemap_fdatawait_range_keep_errors() Ross Zwisler
@ 2019-06-20 15:18 ` Ross Zwisler
2019-06-20 21:25 ` Theodore Ts'o
2019-06-20 15:18 ` [PATCH v2 3/3] ext4: use " Ross Zwisler
2 siblings, 1 reply; 9+ messages in thread
From: Ross Zwisler @ 2019-06-20 15:18 UTC (permalink / raw)
To: linux-kernel
Cc: Ross Zwisler, Theodore Ts'o, Alexander Viro, Andreas Dilger,
Jan Kara, linux-ext4, linux-fsdevel, linux-mm, Fletcher Woodruff,
Justin TerAvest, Jan Kara, stable
Currently both journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() operate on the entire address space
of each of the inodes associated with a given journal entry. The
consequence of this is that if we have an inode where we are constantly
appending dirty pages we can end up waiting for an indefinite amount of
time in journal_finish_inode_data_buffers() while we wait for all the
pages under writeback to be written out.
The easiest way to cause this type of workload is do just dd from
/dev/zero to a file until it fills the entire filesystem. This can
cause journal_finish_inode_data_buffers() to wait for the duration of
the entire dd operation.
We can improve this situation by scoping each of the inode dirty ranges
associated with a given transaction. We do this via the jbd2_inode
structure so that the scoping is contained within jbd2 and so that it
follows the lifetime and locking rules for that structure.
This allows us to limit the writeback & wait in
journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() respectively to the dirty range for
a given struct jdb2_inode, keeping us from waiting forever if the inode
in question is still being appended to.
Signed-off-by: Ross Zwisler <zwisler@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
---
fs/jbd2/commit.c | 23 ++++++++++++++------
fs/jbd2/journal.c | 2 ++
fs/jbd2/transaction.c | 49 ++++++++++++++++++++++++-------------------
include/linux/jbd2.h | 22 +++++++++++++++++++
4 files changed, 69 insertions(+), 27 deletions(-)
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index efd0ce9489ae9..668f9021cf115 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -187,14 +187,15 @@ static int journal_wait_on_commit_record(journal_t *journal,
* use writepages() because with dealyed allocation we may be doing
* block allocation in writepages().
*/
-static int journal_submit_inode_data_buffers(struct address_space *mapping)
+static int journal_submit_inode_data_buffers(struct address_space *mapping,
+ loff_t dirty_start, loff_t dirty_end)
{
int ret;
struct writeback_control wbc = {
.sync_mode = WB_SYNC_ALL,
.nr_to_write = mapping->nrpages * 2,
- .range_start = 0,
- .range_end = i_size_read(mapping->host),
+ .range_start = dirty_start,
+ .range_end = dirty_end,
};
ret = generic_writepages(mapping, &wbc);
@@ -218,6 +219,9 @@ static int journal_submit_data_buffers(journal_t *journal,
spin_lock(&journal->j_list_lock);
list_for_each_entry(jinode, &commit_transaction->t_inode_list, i_list) {
+ loff_t dirty_start = jinode->i_dirty_start;
+ loff_t dirty_end = jinode->i_dirty_end;
+
if (!(jinode->i_flags & JI_WRITE_DATA))
continue;
mapping = jinode->i_vfs_inode->i_mapping;
@@ -230,7 +234,8 @@ static int journal_submit_data_buffers(journal_t *journal,
* only allocated blocks here.
*/
trace_jbd2_submit_inode_data(jinode->i_vfs_inode);
- err = journal_submit_inode_data_buffers(mapping);
+ err = journal_submit_inode_data_buffers(mapping, dirty_start,
+ dirty_end);
if (!ret)
ret = err;
spin_lock(&journal->j_list_lock);
@@ -257,12 +262,16 @@ static int journal_finish_inode_data_buffers(journal_t *journal,
/* For locking, see the comment in journal_submit_data_buffers() */
spin_lock(&journal->j_list_lock);
list_for_each_entry(jinode, &commit_transaction->t_inode_list, i_list) {
+ loff_t dirty_start = jinode->i_dirty_start;
+ loff_t dirty_end = jinode->i_dirty_end;
+
if (!(jinode->i_flags & JI_WAIT_DATA))
continue;
jinode->i_flags |= JI_COMMIT_RUNNING;
spin_unlock(&journal->j_list_lock);
- err = filemap_fdatawait_keep_errors(
- jinode->i_vfs_inode->i_mapping);
+ err = filemap_fdatawait_range_keep_errors(
+ jinode->i_vfs_inode->i_mapping, dirty_start,
+ dirty_end);
if (!ret)
ret = err;
spin_lock(&journal->j_list_lock);
@@ -282,6 +291,8 @@ static int journal_finish_inode_data_buffers(journal_t *journal,
&jinode->i_transaction->t_inode_list);
} else {
jinode->i_transaction = NULL;
+ jinode->i_dirty_start = 0;
+ jinode->i_dirty_end = 0;
}
}
spin_unlock(&journal->j_list_lock);
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 43df0c943229c..288b8e7cf21c7 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -2574,6 +2574,8 @@ void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode)
jinode->i_next_transaction = NULL;
jinode->i_vfs_inode = inode;
jinode->i_flags = 0;
+ jinode->i_dirty_start = 0;
+ jinode->i_dirty_end = 0;
INIT_LIST_HEAD(&jinode->i_list);
}
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 8ca4fddc705fe..990e7b5062e74 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -2565,7 +2565,7 @@ void jbd2_journal_refile_buffer(journal_t *journal, struct journal_head *jh)
* File inode in the inode list of the handle's transaction
*/
static int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *jinode,
- unsigned long flags)
+ unsigned long flags, loff_t start_byte, loff_t end_byte)
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal;
@@ -2577,26 +2577,17 @@ static int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *jinode,
jbd_debug(4, "Adding inode %lu, tid:%d\n", jinode->i_vfs_inode->i_ino,
transaction->t_tid);
- /*
- * First check whether inode isn't already on the transaction's
- * lists without taking the lock. Note that this check is safe
- * without the lock as we cannot race with somebody removing inode
- * from the transaction. The reason is that we remove inode from the
- * transaction only in journal_release_jbd_inode() and when we commit
- * the transaction. We are guarded from the first case by holding
- * a reference to the inode. We are safe against the second case
- * because if jinode->i_transaction == transaction, commit code
- * cannot touch the transaction because we hold reference to it,
- * and if jinode->i_next_transaction == transaction, commit code
- * will only file the inode where we want it.
- */
- if ((jinode->i_transaction == transaction ||
- jinode->i_next_transaction == transaction) &&
- (jinode->i_flags & flags) == flags)
- return 0;
-
spin_lock(&journal->j_list_lock);
jinode->i_flags |= flags;
+
+ if (jinode->i_dirty_end) {
+ jinode->i_dirty_start = min(jinode->i_dirty_start, start_byte);
+ jinode->i_dirty_end = max(jinode->i_dirty_end, end_byte);
+ } else {
+ jinode->i_dirty_start = start_byte;
+ jinode->i_dirty_end = end_byte;
+ }
+
/* Is inode already attached where we need it? */
if (jinode->i_transaction == transaction ||
jinode->i_next_transaction == transaction)
@@ -2631,12 +2622,28 @@ static int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *jinode,
int jbd2_journal_inode_add_write(handle_t *handle, struct jbd2_inode *jinode)
{
return jbd2_journal_file_inode(handle, jinode,
- JI_WRITE_DATA | JI_WAIT_DATA);
+ JI_WRITE_DATA | JI_WAIT_DATA, 0, LLONG_MAX);
}
int jbd2_journal_inode_add_wait(handle_t *handle, struct jbd2_inode *jinode)
{
- return jbd2_journal_file_inode(handle, jinode, JI_WAIT_DATA);
+ return jbd2_journal_file_inode(handle, jinode, JI_WAIT_DATA, 0,
+ LLONG_MAX);
+}
+
+int jbd2_journal_inode_ranged_write(handle_t *handle,
+ struct jbd2_inode *jinode, loff_t start_byte, loff_t length)
+{
+ return jbd2_journal_file_inode(handle, jinode,
+ JI_WRITE_DATA | JI_WAIT_DATA, start_byte,
+ start_byte + length - 1);
+}
+
+int jbd2_journal_inode_ranged_wait(handle_t *handle, struct jbd2_inode *jinode,
+ loff_t start_byte, loff_t length)
+{
+ return jbd2_journal_file_inode(handle, jinode, JI_WAIT_DATA,
+ start_byte, start_byte + length - 1);
}
/*
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 5c04181b7c6d8..0e0393e7f41a4 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -451,6 +451,22 @@ struct jbd2_inode {
* @i_flags: Flags of inode [j_list_lock]
*/
unsigned long i_flags;
+
+ /**
+ * @i_dirty_start:
+ *
+ * Offset in bytes where the dirty range for this inode starts.
+ * [j_list_lock]
+ */
+ loff_t i_dirty_start;
+
+ /**
+ * @i_dirty_end:
+ *
+ * Inclusive offset in bytes where the dirty range for this inode
+ * ends. [j_list_lock]
+ */
+ loff_t i_dirty_end;
};
struct jbd2_revoke_table_s;
@@ -1397,6 +1413,12 @@ extern int jbd2_journal_force_commit(journal_t *);
extern int jbd2_journal_force_commit_nested(journal_t *);
extern int jbd2_journal_inode_add_write(handle_t *handle, struct jbd2_inode *inode);
extern int jbd2_journal_inode_add_wait(handle_t *handle, struct jbd2_inode *inode);
+extern int jbd2_journal_inode_ranged_write(handle_t *handle,
+ struct jbd2_inode *inode, loff_t start_byte,
+ loff_t length);
+extern int jbd2_journal_inode_ranged_wait(handle_t *handle,
+ struct jbd2_inode *inode, loff_t start_byte,
+ loff_t length);
extern int jbd2_journal_begin_ordered_truncate(journal_t *journal,
struct jbd2_inode *inode, loff_t new_size);
extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode);
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v2 3/3] ext4: use jbd2_inode dirty range scoping
2019-06-20 15:18 [PATCH v2 0/3] Add dirty range scoping to jbd2 Ross Zwisler
2019-06-20 15:18 ` [PATCH v2 1/3] mm: add filemap_fdatawait_range_keep_errors() Ross Zwisler
2019-06-20 15:18 ` [PATCH v2 2/3] jbd2: introduce jbd2_inode dirty range scoping Ross Zwisler
@ 2019-06-20 15:18 ` Ross Zwisler
2019-06-20 21:27 ` Theodore Ts'o
2019-06-23 18:54 ` kbuild test robot
2 siblings, 2 replies; 9+ messages in thread
From: Ross Zwisler @ 2019-06-20 15:18 UTC (permalink / raw)
To: linux-kernel
Cc: Ross Zwisler, Theodore Ts'o, Alexander Viro, Andreas Dilger,
Jan Kara, linux-ext4, linux-fsdevel, linux-mm, Fletcher Woodruff,
Justin TerAvest, Jan Kara, stable
Use the newly introduced jbd2_inode dirty range scoping to prevent us
from waiting forever when trying to complete a journal transaction.
Signed-off-by: Ross Zwisler <zwisler@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
---
fs/ext4/ext4_jbd2.h | 12 ++++++------
fs/ext4/inode.c | 13 ++++++++++---
fs/ext4/move_extent.c | 3 ++-
3 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h
index 75a5309f22315..ef8fcf7d0d3b3 100644
--- a/fs/ext4/ext4_jbd2.h
+++ b/fs/ext4/ext4_jbd2.h
@@ -361,20 +361,20 @@ static inline int ext4_journal_force_commit(journal_t *journal)
}
static inline int ext4_jbd2_inode_add_write(handle_t *handle,
- struct inode *inode)
+ struct inode *inode, loff_t start_byte, loff_t length)
{
if (ext4_handle_valid(handle))
- return jbd2_journal_inode_add_write(handle,
- EXT4_I(inode)->jinode);
+ return jbd2_journal_inode_ranged_write(handle,
+ EXT4_I(inode)->jinode, start_byte, length);
return 0;
}
static inline int ext4_jbd2_inode_add_wait(handle_t *handle,
- struct inode *inode)
+ struct inode *inode, loff_t start_byte, loff_t length)
{
if (ext4_handle_valid(handle))
- return jbd2_journal_inode_add_wait(handle,
- EXT4_I(inode)->jinode);
+ return jbd2_journal_inode_ranged_wait(handle,
+ EXT4_I(inode)->jinode, start_byte, length);
return 0;
}
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index c7f77c6430085..27fec5c594459 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -731,10 +731,16 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
!(flags & EXT4_GET_BLOCKS_ZERO) &&
!ext4_is_quota_file(inode) &&
ext4_should_order_data(inode)) {
+ loff_t start_byte =
+ (loff_t)map->m_lblk << inode->i_blkbits;
+ loff_t length = (loff_t)map->m_len << inode->i_blkbits;
+
if (flags & EXT4_GET_BLOCKS_IO_SUBMIT)
- ret = ext4_jbd2_inode_add_wait(handle, inode);
+ ret = ext4_jbd2_inode_add_wait(handle, inode,
+ start_byte, length);
else
- ret = ext4_jbd2_inode_add_write(handle, inode);
+ ret = ext4_jbd2_inode_add_write(handle, inode,
+ start_byte, length);
if (ret)
return ret;
}
@@ -4085,7 +4091,8 @@ static int __ext4_block_zero_page_range(handle_t *handle,
err = 0;
mark_buffer_dirty(bh);
if (ext4_should_order_data(inode))
- err = ext4_jbd2_inode_add_write(handle, inode);
+ err = ext4_jbd2_inode_add_write(handle, inode, from,
+ length);
}
unlock:
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index 1083a9f3f16a1..c7ded4e2adff5 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -390,7 +390,8 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
/* Even in case of data=writeback it is reasonable to pin
* inode to transaction, to prevent unexpected data loss */
- *err = ext4_jbd2_inode_add_write(handle, orig_inode);
+ *err = ext4_jbd2_inode_add_write(handle, orig_inode,
+ (loff_t)orig_page_offset << PAGE_SHIFT, replaced_size);
unlock_pages:
unlock_page(pagep[0]);
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 9+ messages in thread