From eee06c56784496805b198964c59fa8cd7c00bf48 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 28 May 2013 07:31:59 -0400 Subject: jbd2: fix block tag checksum verification brokenness Al Viro complained of a ton of bogosity with regards to the jbd2 block tag header checksum. This one checksum is 16 bits, so cut off the upper 16 bits and treat it as a 16-bit value and don't mess around with be32* conversions. Fortunately metadata checksumming is still "experimental" and not in a shipping e2fsprogs, so there should be few users affected by this. Reported-by: Al Viro Signed-off-by: Darrick J. Wong --- fs/jbd2/commit.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 0f53946f13c..e61d7224a72 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -343,20 +343,21 @@ static void jbd2_block_tag_csum_set(journal_t *j, journal_block_tag_t *tag, { struct page *page = bh->b_page; __u8 *addr; - __u32 csum; + __u32 csum32; if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) return; sequence = cpu_to_be32(sequence); addr = kmap_atomic(page); - csum = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&sequence, - sizeof(sequence)); - csum = jbd2_chksum(j, csum, addr + offset_in_page(bh->b_data), - bh->b_size); + csum32 = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&sequence, + sizeof(sequence)); + csum32 = jbd2_chksum(j, csum32, addr + offset_in_page(bh->b_data), + bh->b_size); kunmap_atomic(addr); - tag->t_checksum = cpu_to_be32(csum); + /* We only have space to store the lower 16 bits of the crc32c. */ + tag->t_checksum = cpu_to_be16(csum32); } /* * jbd2_journal_commit_transaction -- cgit v1.2.3-70-g09d2 From f5113effc2a2ee6b86a4b345ce557353dcbcfffe Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 4 Jun 2013 12:01:45 -0400 Subject: jbd2: don't create journal_head for temporary journal buffers When writing metadata to the journal, we create temporary buffer heads for that task. We also attach journal heads to these buffer heads but the only purpose of the journal heads is to keep buffers linked in transaction's BJ_IO list. We remove the need for journal heads by reusing buffer_head's b_assoc_buffers list for that purpose. Also since BJ_IO list is just a temporary list for transaction commit, we use a private list in jbd2_journal_commit_transaction() for that thus removing BJ_IO list from transaction completely. Reviewed-by: Zheng Liu Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o" --- fs/jbd2/checkpoint.c | 1 - fs/jbd2/commit.c | 65 +++++++++++++++++---------------------------------- fs/jbd2/journal.c | 36 +++++++++++----------------- fs/jbd2/transaction.c | 14 ++++------- include/linux/jbd2.h | 32 ++++++++++++------------- 5 files changed, 56 insertions(+), 92 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c index c78841ee81c..2735fef6e55 100644 --- a/fs/jbd2/checkpoint.c +++ b/fs/jbd2/checkpoint.c @@ -690,7 +690,6 @@ void __jbd2_journal_drop_transaction(journal_t *journal, transaction_t *transact J_ASSERT(transaction->t_state == T_FINISHED); J_ASSERT(transaction->t_buffers == NULL); J_ASSERT(transaction->t_forget == NULL); - J_ASSERT(transaction->t_iobuf_list == NULL); J_ASSERT(transaction->t_shadow_list == NULL); J_ASSERT(transaction->t_log_list == NULL); J_ASSERT(transaction->t_checkpoint_list == NULL); diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index e61d7224a72..57bd2ff9788 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -369,7 +369,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) { struct transaction_stats_s stats; transaction_t *commit_transaction; - struct journal_head *jh, *new_jh, *descriptor; + struct journal_head *jh, *descriptor; struct buffer_head **wbuf = journal->j_wbuf; int bufs; int flags; @@ -393,6 +393,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) tid_t first_tid; int update_tail; int csum_size = 0; + LIST_HEAD(io_bufs); if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2)) csum_size = sizeof(struct jbd2_journal_block_tail); @@ -659,29 +660,22 @@ void jbd2_journal_commit_transaction(journal_t *journal) /* Bump b_count to prevent truncate from stumbling over the shadowed buffer! @@@ This can go if we ever get - rid of the BJ_IO/BJ_Shadow pairing of buffers. */ + rid of the shadow pairing of buffers. */ atomic_inc(&jh2bh(jh)->b_count); - /* Make a temporary IO buffer with which to write it out - (this will requeue both the metadata buffer and the - temporary IO buffer). new_bh goes on BJ_IO*/ - - set_bit(BH_JWrite, &jh2bh(jh)->b_state); /* - * akpm: jbd2_journal_write_metadata_buffer() sets - * new_bh->b_transaction to commit_transaction. - * We need to clean this up before we release new_bh - * (which is of type BJ_IO) + * Make a temporary IO buffer with which to write it out + * (this will requeue the metadata buffer to BJ_Shadow). */ + set_bit(BH_JWrite, &jh2bh(jh)->b_state); JBUFFER_TRACE(jh, "ph3: write metadata"); flags = jbd2_journal_write_metadata_buffer(commit_transaction, - jh, &new_jh, blocknr); + jh, &wbuf[bufs], blocknr); if (flags < 0) { jbd2_journal_abort(journal, flags); continue; } - set_bit(BH_JWrite, &jh2bh(new_jh)->b_state); - wbuf[bufs++] = jh2bh(new_jh); + jbd2_file_log_bh(&io_bufs, wbuf[bufs]); /* Record the new block's tag in the current descriptor buffer */ @@ -695,10 +689,11 @@ void jbd2_journal_commit_transaction(journal_t *journal) tag = (journal_block_tag_t *) tagp; write_tag_block(tag_bytes, tag, jh2bh(jh)->b_blocknr); tag->t_flags = cpu_to_be16(tag_flag); - jbd2_block_tag_csum_set(journal, tag, jh2bh(new_jh), + jbd2_block_tag_csum_set(journal, tag, wbuf[bufs], commit_transaction->t_tid); tagp += tag_bytes; space_left -= tag_bytes; + bufs++; if (first_tag) { memcpy (tagp, journal->j_uuid, 16); @@ -810,7 +805,7 @@ start_journal_io: the log. Before we can commit it, wait for the IO so far to complete. Control buffers being written are on the transaction's t_log_list queue, and metadata buffers are on - the t_iobuf_list queue. + the io_bufs list. Wait for the buffers in reverse order. That way we are less likely to be woken up until all IOs have completed, and @@ -819,46 +814,31 @@ start_journal_io: jbd_debug(3, "JBD2: commit phase 3\n"); - /* - * akpm: these are BJ_IO, and j_list_lock is not needed. - * See __journal_try_to_free_buffer. - */ -wait_for_iobuf: - while (commit_transaction->t_iobuf_list != NULL) { - struct buffer_head *bh; + while (!list_empty(&io_bufs)) { + struct buffer_head *bh = list_entry(io_bufs.prev, + struct buffer_head, + b_assoc_buffers); - jh = commit_transaction->t_iobuf_list->b_tprev; - bh = jh2bh(jh); - if (buffer_locked(bh)) { - wait_on_buffer(bh); - goto wait_for_iobuf; - } - if (cond_resched()) - goto wait_for_iobuf; + wait_on_buffer(bh); + cond_resched(); if (unlikely(!buffer_uptodate(bh))) err = -EIO; - - clear_buffer_jwrite(bh); - - JBUFFER_TRACE(jh, "ph4: unfile after journal write"); - jbd2_journal_unfile_buffer(journal, jh); + jbd2_unfile_log_bh(bh); /* - * ->t_iobuf_list should contain only dummy buffer_heads - * which were created by jbd2_journal_write_metadata_buffer(). + * The list contains temporary buffer heads created by + * jbd2_journal_write_metadata_buffer(). */ BUFFER_TRACE(bh, "dumping temporary bh"); - jbd2_journal_put_journal_head(jh); __brelse(bh); J_ASSERT_BH(bh, atomic_read(&bh->b_count) == 0); free_buffer_head(bh); - /* We also have to unlock and free the corresponding - shadowed buffer */ + /* We also have to refile the corresponding shadowed buffer */ jh = commit_transaction->t_shadow_list->b_tprev; bh = jh2bh(jh); - clear_bit(BH_JWrite, &bh->b_state); + clear_buffer_jwrite(bh); J_ASSERT_BH(bh, buffer_jbddirty(bh)); /* The metadata is now released for reuse, but we need @@ -953,7 +933,6 @@ wait_for_iobuf: J_ASSERT(list_empty(&commit_transaction->t_inode_list)); J_ASSERT(commit_transaction->t_buffers == NULL); J_ASSERT(commit_transaction->t_checkpoint_list == NULL); - J_ASSERT(commit_transaction->t_iobuf_list == NULL); J_ASSERT(commit_transaction->t_shadow_list == NULL); J_ASSERT(commit_transaction->t_log_list == NULL); diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 3cdd285df20..45cdc080e46 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -310,14 +310,12 @@ static void journal_kill_thread(journal_t *journal) * * If the source buffer has already been modified by a new transaction * since we took the last commit snapshot, we use the frozen copy of - * that data for IO. If we end up using the existing buffer_head's data - * for the write, then we *have* to lock the buffer to prevent anyone - * else from using and possibly modifying it while the IO is in - * progress. + * that data for IO. If we end up using the existing buffer_head's data + * for the write, then we have to make sure nobody modifies it while the + * IO is in progress. do_get_write_access() handles this. * - * The function returns a pointer to the buffer_heads to be used for IO. - * - * We assume that the journal has already been locked in this function. + * The function returns a pointer to the buffer_head to be used for IO. + * * * Return value: * <0: Error @@ -330,15 +328,14 @@ static void journal_kill_thread(journal_t *journal) int jbd2_journal_write_metadata_buffer(transaction_t *transaction, struct journal_head *jh_in, - struct journal_head **jh_out, - unsigned long long blocknr) + struct buffer_head **bh_out, + sector_t blocknr) { int need_copy_out = 0; int done_copy_out = 0; int do_escape = 0; char *mapped_data; struct buffer_head *new_bh; - struct journal_head *new_jh; struct page *new_page; unsigned int new_offset; struct buffer_head *bh_in = jh2bh(jh_in); @@ -368,14 +365,13 @@ retry_alloc: /* keep subsequent assertions sane */ atomic_set(&new_bh->b_count, 1); - new_jh = jbd2_journal_add_journal_head(new_bh); /* This sleeps */ + jbd_lock_bh_state(bh_in); +repeat: /* * If a new transaction has already done a buffer copy-out, then * we use that version of the data for the commit. */ - jbd_lock_bh_state(bh_in); -repeat: if (jh_in->b_frozen_data) { done_copy_out = 1; new_page = virt_to_page(jh_in->b_frozen_data); @@ -415,7 +411,7 @@ repeat: jbd_unlock_bh_state(bh_in); tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS); if (!tmp) { - jbd2_journal_put_journal_head(new_jh); + brelse(new_bh); return -ENOMEM; } jbd_lock_bh_state(bh_in); @@ -426,7 +422,7 @@ repeat: jh_in->b_frozen_data = tmp; mapped_data = kmap_atomic(new_page); - memcpy(tmp, mapped_data + new_offset, jh2bh(jh_in)->b_size); + memcpy(tmp, mapped_data + new_offset, bh_in->b_size); kunmap_atomic(mapped_data); new_page = virt_to_page(tmp); @@ -452,14 +448,13 @@ repeat: } set_bh_page(new_bh, new_page, new_offset); - new_jh->b_transaction = NULL; - new_bh->b_size = jh2bh(jh_in)->b_size; - new_bh->b_bdev = transaction->t_journal->j_dev; + new_bh->b_size = bh_in->b_size; + new_bh->b_bdev = journal->j_dev; new_bh->b_blocknr = blocknr; set_buffer_mapped(new_bh); set_buffer_dirty(new_bh); - *jh_out = new_jh; + *bh_out = new_bh; /* * The to-be-written buffer needs to get moved to the io queue, @@ -472,9 +467,6 @@ repeat: spin_unlock(&journal->j_list_lock); jbd_unlock_bh_state(bh_in); - JBUFFER_TRACE(new_jh, "file as BJ_IO"); - jbd2_journal_file_buffer(new_jh, transaction, BJ_IO); - return do_escape | (done_copy_out << 1); } diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index 5d8268ad364..98301090025 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -1601,10 +1601,10 @@ __blist_del_buffer(struct journal_head **list, struct journal_head *jh) * Remove a buffer from the appropriate transaction list. * * Note that this function can *change* the value of - * bh->b_transaction->t_buffers, t_forget, t_iobuf_list, t_shadow_list, - * t_log_list or t_reserved_list. If the caller is holding onto a copy of one - * of these pointers, it could go bad. Generally the caller needs to re-read - * the pointer from the transaction_t. + * bh->b_transaction->t_buffers, t_forget, t_shadow_list, t_log_list or + * t_reserved_list. If the caller is holding onto a copy of one of these + * pointers, it could go bad. Generally the caller needs to re-read the + * pointer from the transaction_t. * * Called under j_list_lock. */ @@ -1634,9 +1634,6 @@ static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh) case BJ_Forget: list = &transaction->t_forget; break; - case BJ_IO: - list = &transaction->t_iobuf_list; - break; case BJ_Shadow: list = &transaction->t_shadow_list; break; @@ -2148,9 +2145,6 @@ void __jbd2_journal_file_buffer(struct journal_head *jh, case BJ_Forget: list = &transaction->t_forget; break; - case BJ_IO: - list = &transaction->t_iobuf_list; - break; case BJ_Shadow: list = &transaction->t_shadow_list; break; diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index 682a63c34d2..57210844b22 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -523,12 +523,6 @@ struct transaction_s */ struct journal_head *t_checkpoint_io_list; - /* - * Doubly-linked circular list of temporary buffers currently undergoing - * IO in the log [j_list_lock] - */ - struct journal_head *t_iobuf_list; - /* * Doubly-linked circular list of metadata buffers being shadowed by log * IO. The IO buffers on the iobuf list and the shadow buffers on this @@ -991,6 +985,14 @@ extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, i extern void __journal_free_buffer(struct journal_head *bh); extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); extern void __journal_clean_data_list(transaction_t *transaction); +static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) +{ + list_add_tail(&bh->b_assoc_buffers, head); +} +static inline void jbd2_unfile_log_bh(struct buffer_head *bh) +{ + list_del_init(&bh->b_assoc_buffers); +} /* Log buffer allocation */ extern struct journal_head * jbd2_journal_get_descriptor_buffer(journal_t *); @@ -1039,11 +1041,10 @@ extern void jbd2_buffer_abort_trigger(struct journal_head *jh, struct jbd2_buffer_trigger_type *triggers); /* Buffer IO */ -extern int -jbd2_journal_write_metadata_buffer(transaction_t *transaction, - struct journal_head *jh_in, - struct journal_head **jh_out, - unsigned long long blocknr); +extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, + struct journal_head *jh_in, + struct buffer_head **bh_out, + sector_t blocknr); /* Transaction locking */ extern void __wait_on_journal (journal_t *); @@ -1286,11 +1287,10 @@ static inline int jbd_space_needed(journal_t *journal) #define BJ_None 0 /* Not journaled */ #define BJ_Metadata 1 /* Normal journaled metadata */ #define BJ_Forget 2 /* Buffer superseded by this transaction */ -#define BJ_IO 3 /* Buffer is for temporary IO use */ -#define BJ_Shadow 4 /* Buffer contents being shadowed to the log */ -#define BJ_LogCtl 5 /* Buffer contains log descriptors */ -#define BJ_Reserved 6 /* Buffer is reserved for access by journal */ -#define BJ_Types 7 +#define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ +#define BJ_LogCtl 4 /* Buffer contains log descriptors */ +#define BJ_Reserved 5 /* Buffer is reserved for access by journal */ +#define BJ_Types 6 extern int jbd_blocks_per_page(struct inode *inode); -- cgit v1.2.3-70-g09d2 From e5a120aeb57f40ae568a5ca1dd6ace53d0213582 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 4 Jun 2013 12:06:01 -0400 Subject: jbd2: remove journal_head from descriptor buffers Similarly as for metadata buffers, also log descriptor buffers don't really need the journal head. So strip it and remove BJ_LogCtl list. Reviewed-by: Zheng Liu Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o" --- fs/jbd2/checkpoint.c | 1 - fs/jbd2/commit.c | 78 ++++++++++++++++++++------------------------------- fs/jbd2/journal.c | 4 +-- fs/jbd2/revoke.c | 49 ++++++++++++++++---------------- fs/jbd2/transaction.c | 6 ---- include/linux/jbd2.h | 19 +++++-------- 6 files changed, 64 insertions(+), 93 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c index 2735fef6e55..65ec076e41f 100644 --- a/fs/jbd2/checkpoint.c +++ b/fs/jbd2/checkpoint.c @@ -691,7 +691,6 @@ void __jbd2_journal_drop_transaction(journal_t *journal, transaction_t *transact J_ASSERT(transaction->t_buffers == NULL); J_ASSERT(transaction->t_forget == NULL); J_ASSERT(transaction->t_shadow_list == NULL); - J_ASSERT(transaction->t_log_list == NULL); J_ASSERT(transaction->t_checkpoint_list == NULL); J_ASSERT(transaction->t_checkpoint_io_list == NULL); J_ASSERT(atomic_read(&transaction->t_updates) == 0); diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 57bd2ff9788..7c6f7eea231 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -85,8 +85,7 @@ nope: __brelse(bh); } -static void jbd2_commit_block_csum_set(journal_t *j, - struct journal_head *descriptor) +static void jbd2_commit_block_csum_set(journal_t *j, struct buffer_head *bh) { struct commit_header *h; __u32 csum; @@ -94,12 +93,11 @@ static void jbd2_commit_block_csum_set(journal_t *j, if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) return; - h = (struct commit_header *)(jh2bh(descriptor)->b_data); + h = (struct commit_header *)(bh->b_data); h->h_chksum_type = 0; h->h_chksum_size = 0; h->h_chksum[0] = 0; - csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data, - j->j_blocksize); + csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize); h->h_chksum[0] = cpu_to_be32(csum); } @@ -116,7 +114,6 @@ static int journal_submit_commit_record(journal_t *journal, struct buffer_head **cbh, __u32 crc32_sum) { - struct journal_head *descriptor; struct commit_header *tmp; struct buffer_head *bh; int ret; @@ -127,12 +124,10 @@ static int journal_submit_commit_record(journal_t *journal, if (is_journal_aborted(journal)) return 0; - descriptor = jbd2_journal_get_descriptor_buffer(journal); - if (!descriptor) + bh = jbd2_journal_get_descriptor_buffer(journal); + if (!bh) return 1; - bh = jh2bh(descriptor); - tmp = (struct commit_header *)bh->b_data; tmp->h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER); tmp->h_blocktype = cpu_to_be32(JBD2_COMMIT_BLOCK); @@ -146,9 +141,9 @@ static int journal_submit_commit_record(journal_t *journal, tmp->h_chksum_size = JBD2_CRC32_CHKSUM_SIZE; tmp->h_chksum[0] = cpu_to_be32(crc32_sum); } - jbd2_commit_block_csum_set(journal, descriptor); + jbd2_commit_block_csum_set(journal, bh); - JBUFFER_TRACE(descriptor, "submit commit block"); + BUFFER_TRACE(bh, "submit commit block"); lock_buffer(bh); clear_buffer_dirty(bh); set_buffer_uptodate(bh); @@ -180,7 +175,6 @@ static int journal_wait_on_commit_record(journal_t *journal, if (unlikely(!buffer_uptodate(bh))) ret = -EIO; put_bh(bh); /* One for getblk() */ - jbd2_journal_put_journal_head(bh2jh(bh)); return ret; } @@ -321,7 +315,7 @@ static void write_tag_block(int tag_bytes, journal_block_tag_t *tag, } static void jbd2_descr_block_csum_set(journal_t *j, - struct journal_head *descriptor) + struct buffer_head *bh) { struct jbd2_journal_block_tail *tail; __u32 csum; @@ -329,12 +323,10 @@ static void jbd2_descr_block_csum_set(journal_t *j, if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) return; - tail = (struct jbd2_journal_block_tail *) - (jh2bh(descriptor)->b_data + j->j_blocksize - + tail = (struct jbd2_journal_block_tail *)(bh->b_data + j->j_blocksize - sizeof(struct jbd2_journal_block_tail)); tail->t_checksum = 0; - csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data, - j->j_blocksize); + csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize); tail->t_checksum = cpu_to_be32(csum); } @@ -369,7 +361,8 @@ void jbd2_journal_commit_transaction(journal_t *journal) { struct transaction_stats_s stats; transaction_t *commit_transaction; - struct journal_head *jh, *descriptor; + struct journal_head *jh; + struct buffer_head *descriptor; struct buffer_head **wbuf = journal->j_wbuf; int bufs; int flags; @@ -394,6 +387,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) int update_tail; int csum_size = 0; LIST_HEAD(io_bufs); + LIST_HEAD(log_bufs); if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2)) csum_size = sizeof(struct jbd2_journal_block_tail); @@ -547,7 +541,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) blk_start_plug(&plug); jbd2_journal_write_revoke_records(journal, commit_transaction, - WRITE_SYNC); + &log_bufs, WRITE_SYNC); blk_finish_plug(&plug); jbd_debug(3, "JBD2: commit phase 2\n"); @@ -573,8 +567,8 @@ void jbd2_journal_commit_transaction(journal_t *journal) atomic_read(&commit_transaction->t_outstanding_credits)); err = 0; - descriptor = NULL; bufs = 0; + descriptor = NULL; blk_start_plug(&plug); while (commit_transaction->t_buffers) { @@ -606,8 +600,6 @@ void jbd2_journal_commit_transaction(journal_t *journal) record the metadata buffer. */ if (!descriptor) { - struct buffer_head *bh; - J_ASSERT (bufs == 0); jbd_debug(4, "JBD2: get descriptor\n"); @@ -618,26 +610,26 @@ void jbd2_journal_commit_transaction(journal_t *journal) continue; } - bh = jh2bh(descriptor); jbd_debug(4, "JBD2: got buffer %llu (%p)\n", - (unsigned long long)bh->b_blocknr, bh->b_data); - header = (journal_header_t *)&bh->b_data[0]; + (unsigned long long)descriptor->b_blocknr, + descriptor->b_data); + header = (journal_header_t *)descriptor->b_data; header->h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER); header->h_blocktype = cpu_to_be32(JBD2_DESCRIPTOR_BLOCK); header->h_sequence = cpu_to_be32(commit_transaction->t_tid); - tagp = &bh->b_data[sizeof(journal_header_t)]; - space_left = bh->b_size - sizeof(journal_header_t); + tagp = &descriptor->b_data[sizeof(journal_header_t)]; + space_left = descriptor->b_size - + sizeof(journal_header_t); first_tag = 1; - set_buffer_jwrite(bh); - set_buffer_dirty(bh); - wbuf[bufs++] = bh; + set_buffer_jwrite(descriptor); + set_buffer_dirty(descriptor); + wbuf[bufs++] = descriptor; /* Record it so that we can wait for IO completion later */ - BUFFER_TRACE(bh, "ph3: file as descriptor"); - jbd2_journal_file_buffer(descriptor, commit_transaction, - BJ_LogCtl); + BUFFER_TRACE(descriptor, "ph3: file as descriptor"); + jbd2_file_log_bh(&log_bufs, descriptor); } /* Where is the buffer to be written? */ @@ -864,26 +856,19 @@ start_journal_io: jbd_debug(3, "JBD2: commit phase 4\n"); /* Here we wait for the revoke record and descriptor record buffers */ - wait_for_ctlbuf: - while (commit_transaction->t_log_list != NULL) { + while (!list_empty(&log_bufs)) { struct buffer_head *bh; - jh = commit_transaction->t_log_list->b_tprev; - bh = jh2bh(jh); - if (buffer_locked(bh)) { - wait_on_buffer(bh); - goto wait_for_ctlbuf; - } - if (cond_resched()) - goto wait_for_ctlbuf; + bh = list_entry(log_bufs.prev, struct buffer_head, b_assoc_buffers); + wait_on_buffer(bh); + cond_resched(); if (unlikely(!buffer_uptodate(bh))) err = -EIO; BUFFER_TRACE(bh, "ph5: control buffer writeout done: unfile"); clear_buffer_jwrite(bh); - jbd2_journal_unfile_buffer(journal, jh); - jbd2_journal_put_journal_head(jh); + jbd2_unfile_log_bh(bh); __brelse(bh); /* One for getblk */ /* AKPM: bforget here */ } @@ -934,7 +919,6 @@ start_journal_io: J_ASSERT(commit_transaction->t_buffers == NULL); J_ASSERT(commit_transaction->t_checkpoint_list == NULL); J_ASSERT(commit_transaction->t_shadow_list == NULL); - J_ASSERT(commit_transaction->t_log_list == NULL); restart_loop: /* diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 45cdc080e46..b0a8d1e4703 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -790,7 +790,7 @@ int jbd2_journal_bmap(journal_t *journal, unsigned long blocknr, * But we don't bother doing that, so there will be coherency problems with * mmaps of blockdevs which hold live JBD-controlled filesystems. */ -struct journal_head *jbd2_journal_get_descriptor_buffer(journal_t *journal) +struct buffer_head *jbd2_journal_get_descriptor_buffer(journal_t *journal) { struct buffer_head *bh; unsigned long long blocknr; @@ -809,7 +809,7 @@ struct journal_head *jbd2_journal_get_descriptor_buffer(journal_t *journal) set_buffer_uptodate(bh); unlock_buffer(bh); BUFFER_TRACE(bh, "return this buffer"); - return jbd2_journal_add_journal_head(bh); + return bh; } /* diff --git a/fs/jbd2/revoke.c b/fs/jbd2/revoke.c index f30b80b4ce8..198c9c10276 100644 --- a/fs/jbd2/revoke.c +++ b/fs/jbd2/revoke.c @@ -122,9 +122,10 @@ struct jbd2_revoke_table_s #ifdef __KERNEL__ static void write_one_revoke_record(journal_t *, transaction_t *, - struct journal_head **, int *, + struct list_head *, + struct buffer_head **, int *, struct jbd2_revoke_record_s *, int); -static void flush_descriptor(journal_t *, struct journal_head *, int, int); +static void flush_descriptor(journal_t *, struct buffer_head *, int, int); #endif /* Utility functions to maintain the revoke table */ @@ -531,9 +532,10 @@ void jbd2_journal_switch_revoke_table(journal_t *journal) */ void jbd2_journal_write_revoke_records(journal_t *journal, transaction_t *transaction, + struct list_head *log_bufs, int write_op) { - struct journal_head *descriptor; + struct buffer_head *descriptor; struct jbd2_revoke_record_s *record; struct jbd2_revoke_table_s *revoke; struct list_head *hash_list; @@ -553,7 +555,7 @@ void jbd2_journal_write_revoke_records(journal_t *journal, while (!list_empty(hash_list)) { record = (struct jbd2_revoke_record_s *) hash_list->next; - write_one_revoke_record(journal, transaction, + write_one_revoke_record(journal, transaction, log_bufs, &descriptor, &offset, record, write_op); count++; @@ -573,13 +575,14 @@ void jbd2_journal_write_revoke_records(journal_t *journal, static void write_one_revoke_record(journal_t *journal, transaction_t *transaction, - struct journal_head **descriptorp, + struct list_head *log_bufs, + struct buffer_head **descriptorp, int *offsetp, struct jbd2_revoke_record_s *record, int write_op) { int csum_size = 0; - struct journal_head *descriptor; + struct buffer_head *descriptor; int offset; journal_header_t *header; @@ -609,26 +612,26 @@ static void write_one_revoke_record(journal_t *journal, descriptor = jbd2_journal_get_descriptor_buffer(journal); if (!descriptor) return; - header = (journal_header_t *) &jh2bh(descriptor)->b_data[0]; + header = (journal_header_t *)descriptor->b_data; header->h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER); header->h_blocktype = cpu_to_be32(JBD2_REVOKE_BLOCK); header->h_sequence = cpu_to_be32(transaction->t_tid); /* Record it so that we can wait for IO completion later */ - JBUFFER_TRACE(descriptor, "file as BJ_LogCtl"); - jbd2_journal_file_buffer(descriptor, transaction, BJ_LogCtl); + BUFFER_TRACE(descriptor, "file in log_bufs"); + jbd2_file_log_bh(log_bufs, descriptor); offset = sizeof(jbd2_journal_revoke_header_t); *descriptorp = descriptor; } if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT)) { - * ((__be64 *)(&jh2bh(descriptor)->b_data[offset])) = + * ((__be64 *)(&descriptor->b_data[offset])) = cpu_to_be64(record->blocknr); offset += 8; } else { - * ((__be32 *)(&jh2bh(descriptor)->b_data[offset])) = + * ((__be32 *)(&descriptor->b_data[offset])) = cpu_to_be32(record->blocknr); offset += 4; } @@ -636,8 +639,7 @@ static void write_one_revoke_record(journal_t *journal, *offsetp = offset; } -static void jbd2_revoke_csum_set(journal_t *j, - struct journal_head *descriptor) +static void jbd2_revoke_csum_set(journal_t *j, struct buffer_head *bh) { struct jbd2_journal_revoke_tail *tail; __u32 csum; @@ -645,12 +647,10 @@ static void jbd2_revoke_csum_set(journal_t *j, if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) return; - tail = (struct jbd2_journal_revoke_tail *) - (jh2bh(descriptor)->b_data + j->j_blocksize - + tail = (struct jbd2_journal_revoke_tail *)(bh->b_data + j->j_blocksize - sizeof(struct jbd2_journal_revoke_tail)); tail->r_checksum = 0; - csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data, - j->j_blocksize); + csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize); tail->r_checksum = cpu_to_be32(csum); } @@ -662,25 +662,24 @@ static void jbd2_revoke_csum_set(journal_t *j, */ static void flush_descriptor(journal_t *journal, - struct journal_head *descriptor, + struct buffer_head *descriptor, int offset, int write_op) { jbd2_journal_revoke_header_t *header; - struct buffer_head *bh = jh2bh(descriptor); if (is_journal_aborted(journal)) { - put_bh(bh); + put_bh(descriptor); return; } - header = (jbd2_journal_revoke_header_t *) jh2bh(descriptor)->b_data; + header = (jbd2_journal_revoke_header_t *)descriptor->b_data; header->r_count = cpu_to_be32(offset); jbd2_revoke_csum_set(journal, descriptor); - set_buffer_jwrite(bh); - BUFFER_TRACE(bh, "write"); - set_buffer_dirty(bh); - write_dirty_buffer(bh, write_op); + set_buffer_jwrite(descriptor); + BUFFER_TRACE(descriptor, "write"); + set_buffer_dirty(descriptor); + write_dirty_buffer(descriptor, write_op); } #endif diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index 98301090025..f1c5392e62b 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -1637,9 +1637,6 @@ static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh) case BJ_Shadow: list = &transaction->t_shadow_list; break; - case BJ_LogCtl: - list = &transaction->t_log_list; - break; case BJ_Reserved: list = &transaction->t_reserved_list; break; @@ -2148,9 +2145,6 @@ void __jbd2_journal_file_buffer(struct journal_head *jh, case BJ_Shadow: list = &transaction->t_shadow_list; break; - case BJ_LogCtl: - list = &transaction->t_log_list; - break; case BJ_Reserved: list = &transaction->t_reserved_list; break; diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index 57210844b22..b7dc40da99e 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -530,12 +530,6 @@ struct transaction_s */ struct journal_head *t_shadow_list; - /* - * Doubly-linked circular list of control buffers being written to the - * log. [j_list_lock] - */ - struct journal_head *t_log_list; - /* * List of inodes whose data we've modified in data=ordered mode. * [j_list_lock] @@ -995,7 +989,7 @@ static inline void jbd2_unfile_log_bh(struct buffer_head *bh) } /* Log buffer allocation */ -extern struct journal_head * jbd2_journal_get_descriptor_buffer(journal_t *); +struct buffer_head *jbd2_journal_get_descriptor_buffer(journal_t *journal); int jbd2_journal_next_log_block(journal_t *, unsigned long long *); int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, unsigned long *block); @@ -1179,8 +1173,10 @@ extern int jbd2_journal_init_revoke_caches(void); extern void jbd2_journal_destroy_revoke(journal_t *); extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); -extern void jbd2_journal_write_revoke_records(journal_t *, - transaction_t *, int); +extern void jbd2_journal_write_revoke_records(journal_t *journal, + transaction_t *transaction, + struct list_head *log_bufs, + int write_op); /* Recovery revoke support */ extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); @@ -1288,9 +1284,8 @@ static inline int jbd_space_needed(journal_t *journal) #define BJ_Metadata 1 /* Normal journaled metadata */ #define BJ_Forget 2 /* Buffer superseded by this transaction */ #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ -#define BJ_LogCtl 4 /* Buffer contains log descriptors */ -#define BJ_Reserved 5 /* Buffer is reserved for access by journal */ -#define BJ_Types 6 +#define BJ_Reserved 4 /* Buffer is reserved for access by journal */ +#define BJ_Types 5 extern int jbd_blocks_per_page(struct inode *inode); -- cgit v1.2.3-70-g09d2 From b34090e5e22a02fba0e4473056cce9420ad9dd0b Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 4 Jun 2013 12:08:56 -0400 Subject: jbd2: refine waiting for shadow buffers Currently when we add a buffer to a transaction, we wait until the buffer is removed from BJ_Shadow list (so that we prevent any changes to the buffer that is just written to the journal). This can take unnecessarily long as a lot happens between the time the buffer is submitted to the journal and the time when we remove the buffer from BJ_Shadow list. (e.g. We wait for all data buffers in the transaction, we issue a cache flush, etc.) Also this creates a dependency of do_get_write_access() on transaction commit (namely waiting for data IO to complete) which we want to avoid when implementing transaction reservation. So we modify commit code to set new BH_Shadow flag when temporary shadowing buffer is created and we clear that flag once IO on that buffer is complete. This allows do_get_write_access() to wait only for BH_Shadow bit and thus removes the dependency on data IO completion. Reviewed-by: Zheng Liu Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o" --- fs/jbd2/commit.c | 18 +++++++++--------- fs/jbd2/journal.c | 2 ++ fs/jbd2/transaction.c | 44 +++++++++++++++++++------------------------- include/linux/jbd.h | 25 +++++++++++++++++++++++++ include/linux/jbd2.h | 28 ++++++++++++++++++++++++++++ include/linux/jbd_common.h | 26 -------------------------- 6 files changed, 83 insertions(+), 60 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 7c6f7eea231..d73a0d808ec 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -30,15 +30,22 @@ #include /* - * Default IO end handler for temporary BJ_IO buffer_heads. + * IO end handler for temporary buffer_heads handling writes to the journal. */ static void journal_end_buffer_io_sync(struct buffer_head *bh, int uptodate) { + struct buffer_head *orig_bh = bh->b_private; + BUFFER_TRACE(bh, ""); if (uptodate) set_buffer_uptodate(bh); else clear_buffer_uptodate(bh); + if (orig_bh) { + clear_bit_unlock(BH_Shadow, &orig_bh->b_state); + smp_mb__after_clear_bit(); + wake_up_bit(&orig_bh->b_state, BH_Shadow); + } unlock_buffer(bh); } @@ -832,6 +839,7 @@ start_journal_io: bh = jh2bh(jh); clear_buffer_jwrite(bh); J_ASSERT_BH(bh, buffer_jbddirty(bh)); + J_ASSERT_BH(bh, !buffer_shadow(bh)); /* The metadata is now released for reuse, but we need to remember it against this transaction so that when @@ -839,14 +847,6 @@ start_journal_io: required. */ JBUFFER_TRACE(jh, "file as BJ_Forget"); jbd2_journal_file_buffer(jh, commit_transaction, BJ_Forget); - /* - * Wake up any transactions which were waiting for this IO to - * complete. The barrier must be here so that changes by - * jbd2_journal_file_buffer() take effect before wake_up_bit() - * does the waitqueue check. - */ - smp_mb(); - wake_up_bit(&bh->b_state, BH_Unshadow); JBUFFER_TRACE(jh, "brelse shadowed buffer"); __brelse(bh); } diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index b0a8d1e4703..5ef0712e2f7 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -451,6 +451,7 @@ repeat: new_bh->b_size = bh_in->b_size; new_bh->b_bdev = journal->j_dev; new_bh->b_blocknr = blocknr; + new_bh->b_private = bh_in; set_buffer_mapped(new_bh); set_buffer_dirty(new_bh); @@ -465,6 +466,7 @@ repeat: spin_lock(&journal->j_list_lock); __jbd2_journal_file_buffer(jh_in, transaction, BJ_Shadow); spin_unlock(&journal->j_list_lock); + set_buffer_shadow(bh_in); jbd_unlock_bh_state(bh_in); return do_escape | (done_copy_out << 1); diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index f1c5392e62b..6f4248dd875 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -619,6 +619,12 @@ static void warn_dirty_buffer(struct buffer_head *bh) bdevname(bh->b_bdev, b), (unsigned long long)bh->b_blocknr); } +static int sleep_on_shadow_bh(void *word) +{ + io_schedule(); + return 0; +} + /* * If the buffer is already part of the current transaction, then there * is nothing we need to do. If it is already part of a prior @@ -754,41 +760,29 @@ repeat: * journaled. If the primary copy is already going to * disk then we cannot do copy-out here. */ - if (jh->b_jlist == BJ_Shadow) { - DEFINE_WAIT_BIT(wait, &bh->b_state, BH_Unshadow); - wait_queue_head_t *wqh; - - wqh = bit_waitqueue(&bh->b_state, BH_Unshadow); - + if (buffer_shadow(bh)) { JBUFFER_TRACE(jh, "on shadow: sleep"); jbd_unlock_bh_state(bh); - /* commit wakes up all shadow buffers after IO */ - for ( ; ; ) { - prepare_to_wait(wqh, &wait.wait, - TASK_UNINTERRUPTIBLE); - if (jh->b_jlist != BJ_Shadow) - break; - schedule(); - } - finish_wait(wqh, &wait.wait); + wait_on_bit(&bh->b_state, BH_Shadow, + sleep_on_shadow_bh, TASK_UNINTERRUPTIBLE); goto repeat; } - /* Only do the copy if the currently-owning transaction - * still needs it. If it is on the Forget list, the - * committing transaction is past that stage. The - * buffer had better remain locked during the kmalloc, - * but that should be true --- we hold the journal lock - * still and the buffer is already on the BUF_JOURNAL - * list so won't be flushed. + /* + * Only do the copy if the currently-owning transaction still + * needs it. If buffer isn't on BJ_Metadata list, the + * committing transaction is past that stage (here we use the + * fact that BH_Shadow is set under bh_state lock together with + * refiling to BJ_Shadow list and at this point we know the + * buffer doesn't have BH_Shadow set). * * Subtle point, though: if this is a get_undo_access, * then we will be relying on the frozen_data to contain * the new value of the committed_data record after the * transaction, so we HAVE to force the frozen_data copy - * in that case. */ - - if (jh->b_jlist != BJ_Forget || force_copy) { + * in that case. + */ + if (jh->b_jlist == BJ_Metadata || force_copy) { JBUFFER_TRACE(jh, "generate frozen data"); if (!frozen_buffer) { JBUFFER_TRACE(jh, "allocate memory for buffer"); diff --git a/include/linux/jbd.h b/include/linux/jbd.h index 9c505f1aa1f..2439054a6c9 100644 --- a/include/linux/jbd.h +++ b/include/linux/jbd.h @@ -244,6 +244,31 @@ typedef struct journal_superblock_s #include #include + +enum jbd_state_bits { + BH_JBD /* Has an attached ext3 journal_head */ + = BH_PrivateStart, + BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ + BH_Freed, /* Has been freed (truncated) */ + BH_Revoked, /* Has been revoked from the log */ + BH_RevokeValid, /* Revoked flag is valid */ + BH_JBDDirty, /* Is dirty but journaled */ + BH_State, /* Pins most journal_head state */ + BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ + BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */ + BH_JBDPrivateStart, /* First bit available for private use by FS */ +}; + +BUFFER_FNS(JBD, jbd) +BUFFER_FNS(JWrite, jwrite) +BUFFER_FNS(JBDDirty, jbddirty) +TAS_BUFFER_FNS(JBDDirty, jbddirty) +BUFFER_FNS(Revoked, revoked) +TAS_BUFFER_FNS(Revoked, revoked) +BUFFER_FNS(RevokeValid, revokevalid) +TAS_BUFFER_FNS(RevokeValid, revokevalid) +BUFFER_FNS(Freed, freed) + #include #define J_ASSERT(assert) BUG_ON(!(assert)) diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index b7dc40da99e..e33e84b3d5c 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -302,6 +302,34 @@ typedef struct journal_superblock_s #include #include + +enum jbd_state_bits { + BH_JBD /* Has an attached ext3 journal_head */ + = BH_PrivateStart, + BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ + BH_Freed, /* Has been freed (truncated) */ + BH_Revoked, /* Has been revoked from the log */ + BH_RevokeValid, /* Revoked flag is valid */ + BH_JBDDirty, /* Is dirty but journaled */ + BH_State, /* Pins most journal_head state */ + BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ + BH_Shadow, /* IO on shadow buffer is running */ + BH_Verified, /* Metadata block has been verified ok */ + BH_JBDPrivateStart, /* First bit available for private use by FS */ +}; + +BUFFER_FNS(JBD, jbd) +BUFFER_FNS(JWrite, jwrite) +BUFFER_FNS(JBDDirty, jbddirty) +TAS_BUFFER_FNS(JBDDirty, jbddirty) +BUFFER_FNS(Revoked, revoked) +TAS_BUFFER_FNS(Revoked, revoked) +BUFFER_FNS(RevokeValid, revokevalid) +TAS_BUFFER_FNS(RevokeValid, revokevalid) +BUFFER_FNS(Freed, freed) +BUFFER_FNS(Shadow, shadow) +BUFFER_FNS(Verified, verified) + #include #define J_ASSERT(assert) BUG_ON(!(assert)) diff --git a/include/linux/jbd_common.h b/include/linux/jbd_common.h index 6133679bc4c..b1f708976ff 100644 --- a/include/linux/jbd_common.h +++ b/include/linux/jbd_common.h @@ -1,32 +1,6 @@ #ifndef _LINUX_JBD_STATE_H #define _LINUX_JBD_STATE_H -enum jbd_state_bits { - BH_JBD /* Has an attached ext3 journal_head */ - = BH_PrivateStart, - BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ - BH_Freed, /* Has been freed (truncated) */ - BH_Revoked, /* Has been revoked from the log */ - BH_RevokeValid, /* Revoked flag is valid */ - BH_JBDDirty, /* Is dirty but journaled */ - BH_State, /* Pins most journal_head state */ - BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ - BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */ - BH_Verified, /* Metadata block has been verified ok */ - BH_JBDPrivateStart, /* First bit available for private use by FS */ -}; - -BUFFER_FNS(JBD, jbd) -BUFFER_FNS(JWrite, jwrite) -BUFFER_FNS(JBDDirty, jbddirty) -TAS_BUFFER_FNS(JBDDirty, jbddirty) -BUFFER_FNS(Revoked, revoked) -TAS_BUFFER_FNS(Revoked, revoked) -BUFFER_FNS(RevokeValid, revokevalid) -TAS_BUFFER_FNS(RevokeValid, revokevalid) -BUFFER_FNS(Freed, freed) -BUFFER_FNS(Verified, verified) - static inline struct buffer_head *jh2bh(struct journal_head *jh) { return jh->b_bh; -- cgit v1.2.3-70-g09d2 From 8f7d89f36829b9061a14f9040cda1372f264c4fe Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 4 Jun 2013 12:35:11 -0400 Subject: jbd2: transaction reservation support In some cases we cannot start a transaction because of locking constraints and passing started transaction into those places is not handy either because we could block transaction commit for too long. Transaction reservation is designed to solve these issues. It reserves a handle with given number of credits in the journal and the handle can be later attached to the running transaction without blocking on commit or checkpointing. Reserved handles do not block transaction commit in any way, they only reduce maximum size of the running transaction (because we have to always be prepared to accomodate request for attaching reserved handle). Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4_jbd2.c | 2 +- fs/jbd2/commit.c | 6 + fs/jbd2/journal.c | 2 + fs/jbd2/transaction.c | 328 ++++++++++++++++++++++++++++++++++++-------------- include/linux/jbd2.h | 28 ++++- 5 files changed, 273 insertions(+), 93 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c index 451eb404533..bd25e782ec6 100644 --- a/fs/ext4/ext4_jbd2.c +++ b/fs/ext4/ext4_jbd2.c @@ -62,7 +62,7 @@ handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line, ext4_abort(sb, "Detected aborted journal"); return ERR_PTR(-EROFS); } - return jbd2__journal_start(journal, nblocks, GFP_NOFS, type, line); + return jbd2__journal_start(journal, nblocks, 0, GFP_NOFS, type, line); } int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle) diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index d73a0d808ec..cfbce48adc0 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -523,6 +523,12 @@ void jbd2_journal_commit_transaction(journal_t *journal) */ jbd2_journal_switch_revoke_table(journal); + /* + * Reserved credits cannot be claimed anymore, free them + */ + atomic_sub(atomic_read(&journal->j_reserved_credits), + &commit_transaction->t_outstanding_credits); + trace_jbd2_commit_flushing(journal, commit_transaction); stats.run.rs_flushing = jiffies; stats.run.rs_locked = jbd2_time_diff(stats.run.rs_locked, diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index f43f97ba002..70990d682a0 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1030,6 +1030,7 @@ static journal_t * journal_init_common (void) init_waitqueue_head(&journal->j_wait_done_commit); init_waitqueue_head(&journal->j_wait_commit); init_waitqueue_head(&journal->j_wait_updates); + init_waitqueue_head(&journal->j_wait_reserved); mutex_init(&journal->j_barrier); mutex_init(&journal->j_checkpoint_mutex); spin_lock_init(&journal->j_revoke_lock); @@ -1039,6 +1040,7 @@ static journal_t * journal_init_common (void) journal->j_commit_interval = (HZ * JBD2_DEFAULT_MAX_COMMIT_AGE); journal->j_min_batch_time = 0; journal->j_max_batch_time = 15000; /* 15ms */ + atomic_set(&journal->j_reserved_credits, 0); /* The journal is marked for error until we succeed with recovery! */ journal->j_flags = JBD2_ABORT; diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index f14288b0404..f33342a2a95 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -89,7 +89,8 @@ jbd2_get_transaction(journal_t *journal, transaction_t *transaction) transaction->t_expires = jiffies + journal->j_commit_interval; spin_lock_init(&transaction->t_handle_lock); atomic_set(&transaction->t_updates, 0); - atomic_set(&transaction->t_outstanding_credits, 0); + atomic_set(&transaction->t_outstanding_credits, + atomic_read(&journal->j_reserved_credits)); atomic_set(&transaction->t_handle_count, 0); INIT_LIST_HEAD(&transaction->t_inode_list); INIT_LIST_HEAD(&transaction->t_private_list); @@ -140,6 +141,112 @@ static inline void update_t_max_wait(transaction_t *transaction, #endif } +/* + * Wait until running transaction passes T_LOCKED state. Also starts the commit + * if needed. The function expects running transaction to exist and releases + * j_state_lock. + */ +static void wait_transaction_locked(journal_t *journal) + __releases(journal->j_state_lock) +{ + DEFINE_WAIT(wait); + int need_to_start; + tid_t tid = journal->j_running_transaction->t_tid; + + prepare_to_wait(&journal->j_wait_transaction_locked, &wait, + TASK_UNINTERRUPTIBLE); + need_to_start = !tid_geq(journal->j_commit_request, tid); + read_unlock(&journal->j_state_lock); + if (need_to_start) + jbd2_log_start_commit(journal, tid); + schedule(); + finish_wait(&journal->j_wait_transaction_locked, &wait); +} + +static void sub_reserved_credits(journal_t *journal, int blocks) +{ + atomic_sub(blocks, &journal->j_reserved_credits); + wake_up(&journal->j_wait_reserved); +} + +/* + * Wait until we can add credits for handle to the running transaction. Called + * with j_state_lock held for reading. Returns 0 if handle joined the running + * transaction. Returns 1 if we had to wait, j_state_lock is dropped, and + * caller must retry. + */ +static int add_transaction_credits(journal_t *journal, int blocks, + int rsv_blocks) +{ + transaction_t *t = journal->j_running_transaction; + int needed; + int total = blocks + rsv_blocks; + + /* + * If the current transaction is locked down for commit, wait + * for the lock to be released. + */ + if (t->t_state == T_LOCKED) { + wait_transaction_locked(journal); + return 1; + } + + /* + * If there is not enough space left in the log to write all + * potential buffers requested by this operation, we need to + * stall pending a log checkpoint to free some more log space. + */ + needed = atomic_add_return(total, &t->t_outstanding_credits); + if (needed > journal->j_max_transaction_buffers) { + /* + * If the current transaction is already too large, + * then start to commit it: we can then go back and + * attach this handle to a new transaction. + */ + atomic_sub(total, &t->t_outstanding_credits); + wait_transaction_locked(journal); + return 1; + } + + /* + * The commit code assumes that it can get enough log space + * without forcing a checkpoint. This is *critical* for + * correctness: a checkpoint of a buffer which is also + * associated with a committing transaction creates a deadlock, + * so commit simply cannot force through checkpoints. + * + * We must therefore ensure the necessary space in the journal + * *before* starting to dirty potentially checkpointed buffers + * in the new transaction. + */ + if (jbd2_log_space_left(journal) < jbd2_space_needed(journal)) { + atomic_sub(total, &t->t_outstanding_credits); + read_unlock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); + if (jbd2_log_space_left(journal) < jbd2_space_needed(journal)) + __jbd2_log_wait_for_space(journal); + write_unlock(&journal->j_state_lock); + return 1; + } + + /* No reservation? We are done... */ + if (!rsv_blocks) + return 0; + + needed = atomic_add_return(rsv_blocks, &journal->j_reserved_credits); + /* We allow at most half of a transaction to be reserved */ + if (needed > journal->j_max_transaction_buffers / 2) { + sub_reserved_credits(journal, rsv_blocks); + atomic_sub(total, &t->t_outstanding_credits); + read_unlock(&journal->j_state_lock); + wait_event(journal->j_wait_reserved, + atomic_read(&journal->j_reserved_credits) + rsv_blocks + <= journal->j_max_transaction_buffers / 2); + return 1; + } + return 0; +} + /* * start_this_handle: Given a handle, deal with any locking or stalling * needed to make sure that there is enough journal space for the handle @@ -151,18 +258,24 @@ static int start_this_handle(journal_t *journal, handle_t *handle, gfp_t gfp_mask) { transaction_t *transaction, *new_transaction = NULL; - tid_t tid; - int needed, need_to_start; - int nblocks = handle->h_buffer_credits; + int blocks = handle->h_buffer_credits; + int rsv_blocks = 0; unsigned long ts = jiffies; - if (nblocks > journal->j_max_transaction_buffers) { + /* + * 1/2 of transaction can be reserved so we can practically handle + * only 1/2 of maximum transaction size per operation + */ + if (WARN_ON(blocks > journal->j_max_transaction_buffers / 2)) { printk(KERN_ERR "JBD2: %s wants too many credits (%d > %d)\n", - current->comm, nblocks, - journal->j_max_transaction_buffers); + current->comm, blocks, + journal->j_max_transaction_buffers / 2); return -ENOSPC; } + if (handle->h_rsv_handle) + rsv_blocks = handle->h_rsv_handle->h_buffer_credits; + alloc_transaction: if (!journal->j_running_transaction) { new_transaction = kmem_cache_zalloc(transaction_cache, @@ -199,8 +312,12 @@ repeat: return -EROFS; } - /* Wait on the journal's transaction barrier if necessary */ - if (journal->j_barrier_count) { + /* + * Wait on the journal's transaction barrier if necessary. Specifically + * we allow reserved handles to proceed because otherwise commit could + * deadlock on page writeback not being able to complete. + */ + if (!handle->h_reserved && journal->j_barrier_count) { read_unlock(&journal->j_state_lock); wait_event(journal->j_wait_transaction_locked, journal->j_barrier_count == 0); @@ -213,7 +330,7 @@ repeat: goto alloc_transaction; write_lock(&journal->j_state_lock); if (!journal->j_running_transaction && - !journal->j_barrier_count) { + (handle->h_reserved || !journal->j_barrier_count)) { jbd2_get_transaction(journal, new_transaction); new_transaction = NULL; } @@ -223,75 +340,18 @@ repeat: transaction = journal->j_running_transaction; - /* - * If the current transaction is locked down for commit, wait for the - * lock to be released. - */ - if (transaction->t_state == T_LOCKED) { - DEFINE_WAIT(wait); - - prepare_to_wait(&journal->j_wait_transaction_locked, - &wait, TASK_UNINTERRUPTIBLE); - read_unlock(&journal->j_state_lock); - schedule(); - finish_wait(&journal->j_wait_transaction_locked, &wait); - goto repeat; - } - - /* - * If there is not enough space left in the log to write all potential - * buffers requested by this operation, we need to stall pending a log - * checkpoint to free some more log space. - */ - needed = atomic_add_return(nblocks, - &transaction->t_outstanding_credits); - - if (needed > journal->j_max_transaction_buffers) { + if (!handle->h_reserved) { + /* We may have dropped j_state_lock - restart in that case */ + if (add_transaction_credits(journal, blocks, rsv_blocks)) + goto repeat; + } else { /* - * If the current transaction is already too large, then start - * to commit it: we can then go back and attach this handle to - * a new transaction. + * We have handle reserved so we are allowed to join T_LOCKED + * transaction and we don't have to check for transaction size + * and journal space. */ - DEFINE_WAIT(wait); - - jbd_debug(2, "Handle %p starting new commit...\n", handle); - atomic_sub(nblocks, &transaction->t_outstanding_credits); - prepare_to_wait(&journal->j_wait_transaction_locked, &wait, - TASK_UNINTERRUPTIBLE); - tid = transaction->t_tid; - need_to_start = !tid_geq(journal->j_commit_request, tid); - read_unlock(&journal->j_state_lock); - if (need_to_start) - jbd2_log_start_commit(journal, tid); - schedule(); - finish_wait(&journal->j_wait_transaction_locked, &wait); - goto repeat; - } - - /* - * The commit code assumes that it can get enough log space - * without forcing a checkpoint. This is *critical* for - * correctness: a checkpoint of a buffer which is also - * associated with a committing transaction creates a deadlock, - * so commit simply cannot force through checkpoints. - * - * We must therefore ensure the necessary space in the journal - * *before* starting to dirty potentially checkpointed buffers - * in the new transaction. - * - * The worst part is, any transaction currently committing can - * reduce the free space arbitrarily. Be careful to account for - * those buffers when checkpointing. - */ - if (jbd2_log_space_left(journal) < jbd2_space_needed(journal)) { - jbd_debug(2, "Handle %p waiting for checkpoint...\n", handle); - atomic_sub(nblocks, &transaction->t_outstanding_credits); - read_unlock(&journal->j_state_lock); - write_lock(&journal->j_state_lock); - if (jbd2_log_space_left(journal) < jbd2_space_needed(journal)) - __jbd2_log_wait_for_space(journal); - write_unlock(&journal->j_state_lock); - goto repeat; + sub_reserved_credits(journal, blocks); + handle->h_reserved = 0; } /* OK, account for the buffers that this operation expects to @@ -299,12 +359,12 @@ repeat: */ update_t_max_wait(transaction, ts); handle->h_transaction = transaction; - handle->h_requested_credits = nblocks; + handle->h_requested_credits = blocks; handle->h_start_jiffies = jiffies; atomic_inc(&transaction->t_updates); atomic_inc(&transaction->t_handle_count); - jbd_debug(4, "Handle %p given %d credits (total %d, free %d)\n", - handle, nblocks, + jbd_debug(4, "Handle %p given %d credits (total %d, free %lu)\n", + handle, blocks, atomic_read(&transaction->t_outstanding_credits), jbd2_log_space_left(journal)); read_unlock(&journal->j_state_lock); @@ -338,16 +398,21 @@ static handle_t *new_handle(int nblocks) * * We make sure that the transaction can guarantee at least nblocks of * modified buffers in the log. We block until the log can guarantee - * that much space. - * - * This function is visible to journal users (like ext3fs), so is not - * called with the journal already locked. + * that much space. Additionally, if rsv_blocks > 0, we also create another + * handle with rsv_blocks reserved blocks in the journal. This handle is + * is stored in h_rsv_handle. It is not attached to any particular transaction + * and thus doesn't block transaction commit. If the caller uses this reserved + * handle, it has to set h_rsv_handle to NULL as otherwise jbd2_journal_stop() + * on the parent handle will dispose the reserved one. Reserved handle has to + * be converted to a normal handle using jbd2_journal_start_reserved() before + * it can be used. * * Return a pointer to a newly allocated handle, or an ERR_PTR() value * on failure. */ -handle_t *jbd2__journal_start(journal_t *journal, int nblocks, gfp_t gfp_mask, - unsigned int type, unsigned int line_no) +handle_t *jbd2__journal_start(journal_t *journal, int nblocks, int rsv_blocks, + gfp_t gfp_mask, unsigned int type, + unsigned int line_no) { handle_t *handle = journal_current_handle(); int err; @@ -364,11 +429,25 @@ handle_t *jbd2__journal_start(journal_t *journal, int nblocks, gfp_t gfp_mask, handle = new_handle(nblocks); if (!handle) return ERR_PTR(-ENOMEM); + if (rsv_blocks) { + handle_t *rsv_handle; + + rsv_handle = new_handle(rsv_blocks); + if (!rsv_handle) { + jbd2_free_handle(handle); + return ERR_PTR(-ENOMEM); + } + rsv_handle->h_reserved = 1; + rsv_handle->h_journal = journal; + handle->h_rsv_handle = rsv_handle; + } current->journal_info = handle; err = start_this_handle(journal, handle, gfp_mask); if (err < 0) { + if (handle->h_rsv_handle) + jbd2_free_handle(handle->h_rsv_handle); jbd2_free_handle(handle); current->journal_info = NULL; return ERR_PTR(err); @@ -385,10 +464,68 @@ EXPORT_SYMBOL(jbd2__journal_start); handle_t *jbd2_journal_start(journal_t *journal, int nblocks) { - return jbd2__journal_start(journal, nblocks, GFP_NOFS, 0, 0); + return jbd2__journal_start(journal, nblocks, 0, GFP_NOFS, 0, 0); } EXPORT_SYMBOL(jbd2_journal_start); +void jbd2_journal_free_reserved(handle_t *handle) +{ + journal_t *journal = handle->h_journal; + + WARN_ON(!handle->h_reserved); + sub_reserved_credits(journal, handle->h_buffer_credits); + jbd2_free_handle(handle); +} +EXPORT_SYMBOL(jbd2_journal_free_reserved); + +/** + * int jbd2_journal_start_reserved(handle_t *handle) - start reserved handle + * @handle: handle to start + * + * Start handle that has been previously reserved with jbd2_journal_reserve(). + * This attaches @handle to the running transaction (or creates one if there's + * not transaction running). Unlike jbd2_journal_start() this function cannot + * block on journal commit, checkpointing, or similar stuff. It can block on + * memory allocation or frozen journal though. + * + * Return 0 on success, non-zero on error - handle is freed in that case. + */ +int jbd2_journal_start_reserved(handle_t *handle, unsigned int type, + unsigned int line_no) +{ + journal_t *journal = handle->h_journal; + int ret = -EIO; + + if (WARN_ON(!handle->h_reserved)) { + /* Someone passed in normal handle? Just stop it. */ + jbd2_journal_stop(handle); + return ret; + } + /* + * Usefulness of mixing of reserved and unreserved handles is + * questionable. So far nobody seems to need it so just error out. + */ + if (WARN_ON(current->journal_info)) { + jbd2_journal_free_reserved(handle); + return ret; + } + + handle->h_journal = NULL; + current->journal_info = handle; + /* + * GFP_NOFS is here because callers are likely from writeback or + * similarly constrained call sites + */ + ret = start_this_handle(journal, handle, GFP_NOFS); + if (ret < 0) { + current->journal_info = NULL; + jbd2_journal_free_reserved(handle); + } + handle->h_type = type; + handle->h_line_no = line_no; + return ret; +} +EXPORT_SYMBOL(jbd2_journal_start_reserved); /** * int jbd2_journal_extend() - extend buffer credits. @@ -483,7 +620,8 @@ out: * to a running handle, a call to jbd2_journal_restart will commit the * handle's transaction so far and reattach the handle to a new * transaction capabable of guaranteeing the requested number of - * credits. + * credits. We preserve reserved handle if there's any attached to the + * passed in handle. */ int jbd2__journal_restart(handle_t *handle, int nblocks, gfp_t gfp_mask) { @@ -508,6 +646,10 @@ int jbd2__journal_restart(handle_t *handle, int nblocks, gfp_t gfp_mask) spin_lock(&transaction->t_handle_lock); atomic_sub(handle->h_buffer_credits, &transaction->t_outstanding_credits); + if (handle->h_rsv_handle) { + sub_reserved_credits(journal, + handle->h_rsv_handle->h_buffer_credits); + } if (atomic_dec_and_test(&transaction->t_updates)) wake_up(&journal->j_wait_updates); spin_unlock(&transaction->t_handle_lock); @@ -550,6 +692,14 @@ void jbd2_journal_lock_updates(journal_t *journal) write_lock(&journal->j_state_lock); ++journal->j_barrier_count; + /* Wait until there are no reserved handles */ + if (atomic_read(&journal->j_reserved_credits)) { + write_unlock(&journal->j_state_lock); + wait_event(journal->j_wait_reserved, + atomic_read(&journal->j_reserved_credits) == 0); + write_lock(&journal->j_state_lock); + } + /* Wait until there are no running updates */ while (1) { transaction_t *transaction = journal->j_running_transaction; @@ -1505,6 +1655,8 @@ int jbd2_journal_stop(handle_t *handle) lock_map_release(&handle->h_lockdep_map); + if (handle->h_rsv_handle) + jbd2_journal_free_reserved(handle->h_rsv_handle); jbd2_free_handle(handle); return err; } diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index 8028dd581cb..fb91c8debe6 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -410,8 +410,15 @@ struct jbd2_revoke_table_s; struct jbd2_journal_handle { - /* Which compound transaction is this update a part of? */ - transaction_t *h_transaction; + union { + /* Which compound transaction is this update a part of? */ + transaction_t *h_transaction; + /* Which journal handle belongs to - used iff h_reserved set */ + journal_t *h_journal; + }; + + /* Handle reserved for finishing the logical operation */ + handle_t *h_rsv_handle; /* Number of remaining buffers we are allowed to dirty: */ int h_buffer_credits; @@ -426,6 +433,7 @@ struct jbd2_journal_handle /* Flags [no locking] */ unsigned int h_sync: 1; /* sync-on-close */ unsigned int h_jdata: 1; /* force data journaling */ + unsigned int h_reserved: 1; /* handle with reserved credits */ unsigned int h_aborted: 1; /* fatal error on handle */ unsigned int h_type: 8; /* for handle statistics */ unsigned int h_line_no: 16; /* for handle statistics */ @@ -690,6 +698,7 @@ jbd2_time_diff(unsigned long start, unsigned long end) * @j_wait_done_commit: Wait queue for waiting for commit to complete * @j_wait_commit: Wait queue to trigger commit * @j_wait_updates: Wait queue to wait for updates to complete + * @j_wait_reserved: Wait queue to wait for reserved buffer credits to drop * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints * @j_head: Journal head - identifies the first unused block in the journal * @j_tail: Journal tail - identifies the oldest still-used block in the @@ -703,6 +712,7 @@ jbd2_time_diff(unsigned long start, unsigned long end) * journal * @j_fs_dev: Device which holds the client fs. For internal journal this will * be equal to j_dev + * @j_reserved_credits: Number of buffers reserved from the running transaction * @j_maxlen: Total maximum capacity of the journal region on disk. * @j_list_lock: Protects the buffer lists and internal buffer state. * @j_inode: Optional inode where we store the journal. If present, all journal @@ -801,6 +811,9 @@ struct journal_s /* Wait queue to wait for updates to complete */ wait_queue_head_t j_wait_updates; + /* Wait queue to wait for reserved buffer credits to drop */ + wait_queue_head_t j_wait_reserved; + /* Semaphore for locking against concurrent checkpoints */ struct mutex j_checkpoint_mutex; @@ -855,6 +868,9 @@ struct journal_s /* Total maximum capacity of the journal region on disk. */ unsigned int j_maxlen; + /* Number of buffers reserved from the running transaction */ + atomic_t j_reserved_credits; + /* * Protects the buffer lists and internal buffer state. */ @@ -1091,10 +1107,14 @@ static inline handle_t *journal_current_handle(void) */ extern handle_t *jbd2_journal_start(journal_t *, int nblocks); -extern handle_t *jbd2__journal_start(journal_t *, int nblocks, gfp_t gfp_mask, - unsigned int type, unsigned int line_no); +extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, + gfp_t gfp_mask, unsigned int type, + unsigned int line_no); extern int jbd2_journal_restart(handle_t *, int nblocks); extern int jbd2__journal_restart(handle_t *, int nblocks, gfp_t gfp_mask); +extern int jbd2_journal_start_reserved(handle_t *handle, + unsigned int type, unsigned int line_no); +extern void jbd2_journal_free_reserved(handle_t *handle); extern int jbd2_journal_extend (handle_t *, int nblocks); extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); -- cgit v1.2.3-70-g09d2 From 3ca841c106fd6cd2c942985977a5d126434a8dd6 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Wed, 12 Jun 2013 22:46:35 -0400 Subject: jbd2: relocate assert after state lock in journal_commit_transaction() The state lock is taken after we are doing an assert on the state value, not before. So we might in fact be doing an assert on a transient value. Ensure the state check is within the scope of the state lock being taken. Signed-off-by: Paul Gortmaker Signed-off-by: "Theodore Ts'o" --- fs/jbd2/commit.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index cfbce48adc0..44b42912625 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -427,13 +427,13 @@ void jbd2_journal_commit_transaction(journal_t *journal) J_ASSERT(journal->j_committing_transaction == NULL); commit_transaction = journal->j_running_transaction; - J_ASSERT(commit_transaction->t_state == T_RUNNING); trace_jbd2_start_commit(journal, commit_transaction); jbd_debug(1, "JBD2: starting commit of transaction %d\n", commit_transaction->t_tid); write_lock(&journal->j_state_lock); + J_ASSERT(commit_transaction->t_state == T_RUNNING); commit_transaction->t_state = T_LOCKED; trace_jbd2_commit_locking(journal, commit_transaction); -- cgit v1.2.3-70-g09d2 From cfc7bc896f45251bdcfa45e0d62fda0566e95c4a Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Wed, 12 Jun 2013 22:56:35 -0400 Subject: jbd2: fix duplicate debug label for phase 2 Currently we see this output: $git grep phase fs/jbd2 fs/jbd2/commit.c: jbd_debug(3, "JBD2: commit phase 1\n"); fs/jbd2/commit.c: jbd_debug(3, "JBD2: commit phase 2\n"); fs/jbd2/commit.c: jbd_debug(3, "JBD2: commit phase 2\n"); fs/jbd2/commit.c: jbd_debug(3, "JBD2: commit phase 3\n"); fs/jbd2/commit.c: jbd_debug(3, "JBD2: commit phase 4\n"); [...] There is clearly a duplicate label for phase 2, and they are both active (i.e. not in #if ... #else block). Rename them to be "2a" and "2b" so the debug output is unambiguous. Signed-off-by: Paul Gortmaker Signed-off-by: "Theodore Ts'o" --- fs/jbd2/commit.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 44b42912625..559bec1a37b 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -542,7 +542,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) wake_up(&journal->j_wait_transaction_locked); write_unlock(&journal->j_state_lock); - jbd_debug(3, "JBD2: commit phase 2\n"); + jbd_debug(3, "JBD2: commit phase 2a\n"); /* * Now start flushing things to disk, in the order they appear @@ -557,7 +557,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) &log_bufs, WRITE_SYNC); blk_finish_plug(&plug); - jbd_debug(3, "JBD2: commit phase 2\n"); + jbd_debug(3, "JBD2: commit phase 2b\n"); /* * Way to go: we have now written out all of the data for a -- cgit v1.2.3-70-g09d2