diff options
Diffstat (limited to 'fs/jbd/commit.c')
| -rw-r--r-- | fs/jbd/commit.c | 270 |
1 files changed, 178 insertions, 92 deletions
diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c index ae08c057e751..bb217dcb41af 100644 --- a/fs/jbd/commit.c +++ b/fs/jbd/commit.c @@ -17,9 +17,11 @@ #include <linux/fs.h> #include <linux/jbd.h> #include <linux/errno.h> -#include <linux/slab.h> #include <linux/mm.h> #include <linux/pagemap.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <trace/events/jbd.h> /* * Default IO end handler for temporary BJ_IO buffer_heads. @@ -84,7 +86,12 @@ nope: static void release_data_buffer(struct buffer_head *bh) { if (buffer_freed(bh)) { + WARN_ON_ONCE(buffer_dirty(bh)); clear_buffer_freed(bh); + clear_buffer_mapped(bh); + clear_buffer_new(bh); + clear_buffer_req(bh); + bh->b_bdev = NULL; release_buffer_page(bh); } else put_bh(bh); @@ -119,7 +126,6 @@ static int journal_write_commit_record(journal_t *journal, struct buffer_head *bh; journal_header_t *header; int ret; - int barrier_done = 0; if (is_journal_aborted(journal)) return 0; @@ -137,48 +143,36 @@ static int journal_write_commit_record(journal_t *journal, JBUFFER_TRACE(descriptor, "write commit block"); set_buffer_dirty(bh); - if (journal->j_flags & JFS_BARRIER) { - set_buffer_ordered(bh); - barrier_done = 1; - } - ret = sync_dirty_buffer(bh); - if (barrier_done) - clear_buffer_ordered(bh); - /* is it possible for another commit to fail at roughly - * the same time as this one? If so, we don't want to - * trust the barrier flag in the super, but instead want - * to remember if we sent a barrier request - */ - if (ret == -EOPNOTSUPP && barrier_done) { - char b[BDEVNAME_SIZE]; - printk(KERN_WARNING - "JBD: barrier-based sync failed on %s - " - "disabling barriers\n", - bdevname(journal->j_dev, b)); - spin_lock(&journal->j_state_lock); - journal->j_flags &= ~JFS_BARRIER; - spin_unlock(&journal->j_state_lock); - - /* And try again, without the barrier */ - set_buffer_uptodate(bh); - set_buffer_dirty(bh); + if (journal->j_flags & JFS_BARRIER) + ret = __sync_dirty_buffer(bh, WRITE_SYNC | WRITE_FLUSH_FUA); + else ret = sync_dirty_buffer(bh); - } + put_bh(bh); /* One for getblk() */ journal_put_journal_head(descriptor); return (ret == -EIO); } -static void journal_do_submit_data(struct buffer_head **wbuf, int bufs) +static void journal_do_submit_data(struct buffer_head **wbuf, int bufs, + int write_op) { int i; for (i = 0; i < bufs; i++) { wbuf[i]->b_end_io = end_buffer_write_sync; - /* We use-up our safety reference in submit_bh() */ - submit_bh(WRITE, wbuf[i]); + /* + * Here we write back pagecache data that may be mmaped. Since + * we cannot afford to clean the page and set PageWriteback + * here due to lock ordering (page lock ranks above transaction + * start), the data can change while IO is in flight. Tell the + * block layer it should bounce the bio pages if stable data + * during write is required. + * + * We use up our safety reference in submit_bh(). + */ + _submit_bh(write_op, wbuf[i], 1 << BIO_SNAP_STABLE); } } @@ -186,7 +180,8 @@ static void journal_do_submit_data(struct buffer_head **wbuf, int bufs) * Submit all the data buffers to disk */ static int journal_submit_data_buffers(journal_t *journal, - transaction_t *commit_transaction) + transaction_t *commit_transaction, + int write_op) { struct journal_head *jh; struct buffer_head *bh; @@ -224,8 +219,10 @@ write_out_data: if (!trylock_buffer(bh)) { BUFFER_TRACE(bh, "needs blocking lock"); spin_unlock(&journal->j_list_lock); + trace_jbd_do_submit_data(journal, + commit_transaction); /* Write out all data to prevent deadlocks */ - journal_do_submit_data(wbuf, bufs); + journal_do_submit_data(wbuf, bufs, write_op); bufs = 0; lock_buffer(bh); spin_lock(&journal->j_list_lock); @@ -238,7 +235,7 @@ write_out_data: spin_lock(&journal->j_list_lock); } /* Someone already cleaned up the buffer? */ - if (!buffer_jbd(bh) + if (!buffer_jbd(bh) || bh2jh(bh) != jh || jh->b_transaction != commit_transaction || jh->b_jlist != BJ_SyncData) { jbd_unlock_bh_state(bh); @@ -256,7 +253,9 @@ write_out_data: jbd_unlock_bh_state(bh); if (bufs == journal->j_wbufsize) { spin_unlock(&journal->j_list_lock); - journal_do_submit_data(wbuf, bufs); + trace_jbd_do_submit_data(journal, + commit_transaction); + journal_do_submit_data(wbuf, bufs, write_op); bufs = 0; goto write_out_data; } @@ -273,10 +272,6 @@ write_out_data: jbd_unlock_bh_state(bh); if (locked) unlock_buffer(bh); - journal_remove_journal_head(bh); - /* One for our safety reference, other for - * journal_remove_journal_head() */ - put_bh(bh); release_data_buffer(bh); } @@ -286,7 +281,8 @@ write_out_data: } } spin_unlock(&journal->j_list_lock); - journal_do_submit_data(wbuf, bufs); + trace_jbd_do_submit_data(journal, commit_transaction); + journal_do_submit_data(wbuf, bufs, write_op); return err; } @@ -305,7 +301,9 @@ void journal_commit_transaction(journal_t *journal) int bufs; int flags; int err; - unsigned long blocknr; + unsigned int blocknr; + ktime_t start_time; + u64 commit_time; char *tagp = NULL; journal_header_t *header; journal_block_tag_t *tag = NULL; @@ -313,22 +311,27 @@ void journal_commit_transaction(journal_t *journal) int first_tag = 0; int tag_flag; int i; + struct blk_plug plug; + int write_op = WRITE; /* * First job: lock down the current transaction and wait for * all outstanding updates to complete. */ -#ifdef COMMIT_STATS - spin_lock(&journal->j_list_lock); - summarise_journal_usage(journal); - spin_unlock(&journal->j_list_lock); -#endif - /* Do we need to erase the effects of a prior journal_flush? */ if (journal->j_flags & JFS_FLUSHED) { jbd_debug(3, "super block updated\n"); - journal_update_superblock(journal, 1); + mutex_lock(&journal->j_checkpoint_mutex); + /* + * We hold j_checkpoint_mutex so tail cannot change under us. + * We don't need any special data guarantees for writing sb + * since journal is empty and it is ok for write to be + * flushed only with transaction commit. + */ + journal_update_sb_log_tail(journal, journal->j_tail_sequence, + journal->j_tail, WRITE_SYNC); + mutex_unlock(&journal->j_checkpoint_mutex); } else { jbd_debug(3, "superblock not updated\n"); } @@ -337,14 +340,16 @@ void 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_jbd_start_commit(journal, commit_transaction); jbd_debug(1, "JBD: starting commit of transaction %d\n", commit_transaction->t_tid); spin_lock(&journal->j_state_lock); + J_ASSERT(commit_transaction->t_state == T_RUNNING); commit_transaction->t_state = T_LOCKED; + trace_jbd_commit_locking(journal, commit_transaction); spin_lock(&commit_transaction->t_handle_lock); while (commit_transaction->t_updates) { DEFINE_WAIT(wait); @@ -379,7 +384,7 @@ void journal_commit_transaction(journal_t *journal) * we do not require it to remember exactly which old buffers it * has reserved. This is consistent with the existing behaviour * that multiple journal_get_write_access() calls to the same - * buffer are perfectly permissable. + * buffer are perfectly permissible. */ while (commit_transaction->t_reserved_list) { jh = commit_transaction->t_reserved_list; @@ -411,24 +416,38 @@ void journal_commit_transaction(journal_t *journal) jbd_debug (3, "JBD: commit phase 1\n"); /* + * Clear revoked flag to reflect there is no revoked buffers + * in the next transaction which is going to be started. + */ + journal_clear_buffer_revoked_flags(journal); + + /* * Switch to a new revoke table. */ journal_switch_revoke_table(journal); + trace_jbd_commit_flushing(journal, commit_transaction); commit_transaction->t_state = T_FLUSH; journal->j_committing_transaction = commit_transaction; journal->j_running_transaction = NULL; + start_time = ktime_get(); commit_transaction->t_log_start = journal->j_head; wake_up(&journal->j_wait_transaction_locked); spin_unlock(&journal->j_state_lock); jbd_debug (3, "JBD: commit phase 2\n"); + if (tid_geq(journal->j_commit_waited, commit_transaction->t_tid)) + write_op = WRITE_SYNC; + /* * Now start flushing things to disk, in the order they appear * on the transaction lists. Data blocks go first. */ - err = journal_submit_data_buffers(journal, commit_transaction); + blk_start_plug(&plug); + err = journal_submit_data_buffers(journal, commit_transaction, + write_op); + blk_finish_plug(&plug); /* * Wait for all previously submitted IO to complete. @@ -463,14 +482,11 @@ void journal_commit_transaction(journal_t *journal) spin_lock(&journal->j_list_lock); continue; } - if (buffer_jbd(bh) && jh->b_jlist == BJ_Locked) { + if (buffer_jbd(bh) && bh2jh(bh) == jh && + jh->b_transaction == commit_transaction && + jh->b_jlist == BJ_Locked) __journal_unfile_buffer(jh); - jbd_unlock_bh_state(bh); - journal_remove_journal_head(bh); - put_bh(bh); - } else { - jbd_unlock_bh_state(bh); - } + jbd_unlock_bh_state(bh); release_data_buffer(bh); cond_resched_lock(&journal->j_list_lock); } @@ -482,10 +498,14 @@ void journal_commit_transaction(journal_t *journal) printk(KERN_WARNING "JBD: Detected IO errors while flushing file data " "on %s\n", bdevname(journal->j_fs_dev, b)); + if (journal->j_flags & JFS_ABORT_ON_SYNCDATA_ERR) + journal_abort(journal, err); err = 0; } - journal_write_revoke_records(journal, commit_transaction); + blk_start_plug(&plug); + + journal_write_revoke_records(journal, commit_transaction, write_op); /* * If we found any dirty or locked buffers, then we should have @@ -506,6 +526,7 @@ void journal_commit_transaction(journal_t *journal) commit_transaction->t_state = T_COMMIT; spin_unlock(&journal->j_state_lock); + trace_jbd_commit_logging(journal, commit_transaction); J_ASSERT(commit_transaction->t_nr_buffers <= commit_transaction->t_outstanding_credits); @@ -518,9 +539,10 @@ void journal_commit_transaction(journal_t *journal) jh = commit_transaction->t_buffers; /* If we're in abort mode, we just un-journal the buffer and - release it for background writing. */ + release it. */ if (is_journal_aborted(journal)) { + clear_buffer_jbddirty(jh2bh(jh)); JBUFFER_TRACE(jh, "journal is aborting: refile"); journal_refile_buffer(journal, jh); /* If that was the last one, we need to clean up @@ -591,13 +613,13 @@ void 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. */ - atomic_inc(&jh2bh(jh)->b_count); + get_bh(jh2bh(jh)); /* 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); + set_buffer_jwrite(jh2bh(jh)); /* * akpm: journal_write_metadata_buffer() sets * new_bh->b_transaction to commit_transaction. @@ -607,7 +629,7 @@ void journal_commit_transaction(journal_t *journal) JBUFFER_TRACE(jh, "ph3: write metadata"); flags = journal_write_metadata_buffer(commit_transaction, jh, &new_jh, blocknr); - set_bit(BH_JWrite, &jh2bh(new_jh)->b_state); + set_buffer_jwrite(jh2bh(new_jh)); wbuf[bufs++] = jh2bh(new_jh); /* Record the new block's tag in the current descriptor @@ -654,7 +676,17 @@ start_journal_io: clear_buffer_dirty(bh); set_buffer_uptodate(bh); bh->b_end_io = journal_end_buffer_io_sync; - submit_bh(WRITE, bh); + /* + * In data=journal mode, here we can end up + * writing pagecache data that might be + * mmapped. Since we can't afford to clean the + * page and set PageWriteback (see the comment + * near the other use of _submit_bh()), the + * data can change while the write is in + * flight. Tell the block layer to bounce the + * bio pages if stable pages are required. + */ + _submit_bh(write_op, bh, 1 << BIO_SNAP_STABLE); } cond_resched(); @@ -665,6 +697,8 @@ start_journal_io: } } + blk_finish_plug(&plug); + /* Lo and behold: we have just managed to send a transaction to the log. Before we can commit it, wait for the IO so far to complete. Control buffers being written are on the @@ -717,7 +751,7 @@ wait_for_iobuf: 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 @@ -726,8 +760,13 @@ wait_for_iobuf: required. */ JBUFFER_TRACE(jh, "file as BJ_Forget"); journal_file_buffer(jh, commit_transaction, BJ_Forget); - /* Wake up any transactions which were waiting for this - IO to complete */ + /* + * Wake up any transactions which were waiting for this + * IO to complete. The barrier must be here so that changes + * by 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); @@ -762,8 +801,17 @@ wait_for_iobuf: /* AKPM: bforget here */ } + if (err) + journal_abort(journal, err); + jbd_debug(3, "JBD: commit phase 6\n"); + /* All metadata is written, now write commit record and do cleanup */ + spin_lock(&journal->j_state_lock); + J_ASSERT(commit_transaction->t_state == T_COMMIT); + commit_transaction->t_state = T_COMMIT_RECORD; + spin_unlock(&journal->j_state_lock); + if (journal_write_commit_record(journal, commit_transaction)) err = -EIO; @@ -793,10 +841,16 @@ restart_loop: while (commit_transaction->t_forget) { transaction_t *cp_transaction; struct buffer_head *bh; + int try_to_free = 0; jh = commit_transaction->t_forget; spin_unlock(&journal->j_list_lock); bh = jh2bh(jh); + /* + * Get a reference so that bh cannot be freed before we are + * done with it. + */ + get_bh(bh); jbd_lock_bh_state(bh); J_ASSERT_JH(jh, jh->b_transaction == commit_transaction || jh->b_transaction == journal->j_running_transaction); @@ -836,44 +890,63 @@ restart_loop: * there's no point in keeping a checkpoint record for * it. */ - /* A buffer which has been freed while still being - * journaled by a previous transaction may end up still - * being dirty here, but we want to avoid writing back - * that buffer in the future now that the last use has - * been committed. That's not only a performance gain, - * it also stops aliasing problems if the buffer is left - * behind for writeback and gets reallocated for another - * use in a different page. */ + /* + * A buffer which has been freed while still being journaled by + * a previous transaction. + */ if (buffer_freed(bh)) { - clear_buffer_freed(bh); - clear_buffer_jbddirty(bh); + /* + * If the running transaction is the one containing + * "add to orphan" operation (b_next_transaction != + * NULL), we have to wait for that transaction to + * commit before we can really get rid of the buffer. + * So just clear b_modified to not confuse transaction + * credit accounting and refile the buffer to + * BJ_Forget of the running transaction. If the just + * committed transaction contains "add to orphan" + * operation, we can completely invalidate the buffer + * now. We are rather throughout in that since the + * buffer may be still accessible when blocksize < + * pagesize and it is attached to the last partial + * page. + */ + jh->b_modified = 0; + if (!jh->b_next_transaction) { + clear_buffer_freed(bh); + clear_buffer_jbddirty(bh); + clear_buffer_mapped(bh); + clear_buffer_new(bh); + clear_buffer_req(bh); + bh->b_bdev = NULL; + } } if (buffer_jbddirty(bh)) { JBUFFER_TRACE(jh, "add to new checkpointing trans"); __journal_insert_checkpoint(jh, commit_transaction); - JBUFFER_TRACE(jh, "refile for checkpoint writeback"); - __journal_refile_buffer(jh); - jbd_unlock_bh_state(bh); + if (is_journal_aborted(journal)) + clear_buffer_jbddirty(bh); } else { J_ASSERT_BH(bh, !buffer_dirty(bh)); - /* The buffer on BJ_Forget list and not jbddirty means + /* + * The buffer on BJ_Forget list and not jbddirty means * it has been freed by this transaction and hence it * could not have been reallocated until this * transaction has committed. *BUT* it could be * reallocated once we have written all the data to * disk and before we process the buffer on BJ_Forget - * list. */ - JBUFFER_TRACE(jh, "refile or unfile freed buffer"); - __journal_refile_buffer(jh); - if (!jh->b_transaction) { - jbd_unlock_bh_state(bh); - /* needs a brelse */ - journal_remove_journal_head(bh); - release_buffer_page(bh); - } else - jbd_unlock_bh_state(bh); + * list. + */ + if (!jh->b_next_transaction) + try_to_free = 1; } + JBUFFER_TRACE(jh, "refile or unfile freed buffer"); + __journal_refile_buffer(jh); + jbd_unlock_bh_state(bh); + if (try_to_free) + release_buffer_page(bh); + else + __brelse(bh); cond_resched_lock(&journal->j_list_lock); } spin_unlock(&journal->j_list_lock); @@ -899,12 +972,24 @@ restart_loop: jbd_debug(3, "JBD: commit phase 8\n"); - J_ASSERT(commit_transaction->t_state == T_COMMIT); + J_ASSERT(commit_transaction->t_state == T_COMMIT_RECORD); commit_transaction->t_state = T_FINISHED; J_ASSERT(commit_transaction == journal->j_committing_transaction); journal->j_commit_sequence = commit_transaction->t_tid; journal->j_committing_transaction = NULL; + commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time)); + + /* + * weight the commit time higher than the average time so we don't + * react too strongly to vast changes in commit time + */ + if (likely(journal->j_average_commit_time)) + journal->j_average_commit_time = (commit_time*3 + + journal->j_average_commit_time) / 4; + else + journal->j_average_commit_time = commit_time; + spin_unlock(&journal->j_state_lock); if (commit_transaction->t_checkpoint_list == NULL && @@ -928,6 +1013,7 @@ restart_loop: } spin_unlock(&journal->j_list_lock); + trace_jbd_end_commit(journal, commit_transaction); jbd_debug(1, "JBD: commit %d complete, head %d\n", journal->j_commit_sequence, journal->j_tail_sequence); |