ref: e970afced259e8a524cef8cd1d74120e3c70eb1a
parent: 9cc36f15cc9a72a2b53470533704e31f7616f846
author: ngkaho1234 <[email protected]>
date: Mon Dec 14 11:10:58 EST 2015
ext4_journal: some changes below. - check whether buffer going to be added is dirty. - skip checkpoint on transactions having no data block.
--- a/lwext4/ext4_journal.c
+++ b/lwext4/ext4_journal.c
@@ -831,7 +831,13 @@
int jbd_trans_add_block(struct jbd_trans *trans,
struct ext4_block *block)
{- struct jbd_buf *buf = calloc(1, sizeof(struct jbd_buf));
+ struct jbd_buf *buf;
+ /* We do not need to add those unmodified buffer to
+ * a transaction. */
+ if (!ext4_bcache_test_flag(block->buf, BC_DIRTY))
+ return EOK;
+
+ buf = calloc(1, sizeof(struct jbd_buf));
if (!buf)
return ENOMEM;
@@ -946,6 +952,10 @@
uuid_exist = true;
tag_tbl_size = journal->block_size -
sizeof(struct jbd_bhdr);
+
+ if (!trans->start_iblock)
+ trans->start_iblock = desc_iblock;
+
}
tag_info.block = jbd_buf->block.lb_id;
tag_info.uuid_exist = uuid_exist;
@@ -1032,6 +1042,10 @@
blocks_entry = (char *)(header + 1);
tag_tbl_size = journal->block_size -
sizeof(struct jbd_revoke_header);
+
+ if (!trans->start_iblock)
+ trans->start_iblock = desc_iblock;
+
}
if (tag_tbl_size < record_len) {@@ -1097,8 +1111,9 @@
trans->written_cnt++;
if (trans->written_cnt == trans->data_cnt) {TAILQ_REMOVE(&journal->cp_queue, trans, trans_node);
- journal->start += trans->alloc_blocks;
- journal->trans_id = ++trans->trans_id;
+ journal->start = trans->start_iblock +
+ trans->alloc_blocks;
+ journal->trans_id = trans->trans_id + 1;
jbd_journal_write_sb(journal);
jbd_write_sb(journal->jbd_fs);
jbd_journal_free_trans(journal, trans, false);
@@ -1134,11 +1149,14 @@
goto Finish;
journal->alloc_trans_id++;
- TAILQ_INSERT_TAIL(&journal->cp_queue, trans,
- trans_node);
- if (trans == TAILQ_FIRST(&journal->cp_queue)) {- jbd_journal_cp_trans(journal, trans);
- }
+ if (trans->data_cnt) {+ TAILQ_INSERT_TAIL(&journal->cp_queue, trans,
+ trans_node);
+ if (trans == TAILQ_FIRST(&journal->cp_queue)) {+ jbd_journal_cp_trans(journal, trans);
+ }
+ } else
+ jbd_journal_free_trans(journal, trans, false);
}
Finish:
if (rc != EOK) {--- a/lwext4/ext4_types.h
+++ b/lwext4/ext4_types.h
@@ -1107,6 +1107,7 @@
struct jbd_trans {uint32_t trans_id;
+ uint32_t start_iblock;
int alloc_blocks;
int data_cnt;
int written_cnt;