diff options
Diffstat (limited to 'fs/jbd2/journal.c')
-rw-r--r-- | fs/jbd2/journal.c | 149 |
1 files changed, 60 insertions, 89 deletions
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 152880c298ca..35302bc192eb 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1283,6 +1283,48 @@ static int jbd2_min_tag_size(void) return sizeof(journal_block_tag_t) - 4; } +/** + * jbd2_journal_shrink_scan() + * + * Scan the checkpointed buffer on the checkpoint list and release the + * journal_head. + */ +static unsigned long jbd2_journal_shrink_scan(struct shrinker *shrink, + struct shrink_control *sc) +{ + journal_t *journal = container_of(shrink, journal_t, j_shrinker); + unsigned long nr_to_scan = sc->nr_to_scan; + unsigned long nr_shrunk; + unsigned long count; + + count = percpu_counter_read_positive(&journal->j_checkpoint_jh_count); + trace_jbd2_shrink_scan_enter(journal, sc->nr_to_scan, count); + + nr_shrunk = jbd2_journal_shrink_checkpoint_list(journal, &nr_to_scan); + + count = percpu_counter_read_positive(&journal->j_checkpoint_jh_count); + trace_jbd2_shrink_scan_exit(journal, nr_to_scan, nr_shrunk, count); + + return nr_shrunk; +} + +/** + * jbd2_journal_shrink_count() + * + * Count the number of checkpoint buffers on the checkpoint list. + */ +static unsigned long jbd2_journal_shrink_count(struct shrinker *shrink, + struct shrink_control *sc) +{ + journal_t *journal = container_of(shrink, journal_t, j_shrinker); + unsigned long count; + + count = percpu_counter_read_positive(&journal->j_checkpoint_jh_count); + trace_jbd2_shrink_count(journal, sc->nr_to_scan, count); + + return count; +} + /* * Management for journal control blocks: functions to create and * destroy journal_t structures, and to initialise and read existing @@ -1361,9 +1403,23 @@ static journal_t *journal_init_common(struct block_device *bdev, journal->j_sb_buffer = bh; journal->j_superblock = (journal_superblock_t *)bh->b_data; + journal->j_shrink_transaction = NULL; + journal->j_shrinker.scan_objects = jbd2_journal_shrink_scan; + journal->j_shrinker.count_objects = jbd2_journal_shrink_count; + journal->j_shrinker.seeks = DEFAULT_SEEKS; + journal->j_shrinker.batch = journal->j_max_transaction_buffers; + + if (percpu_counter_init(&journal->j_checkpoint_jh_count, 0, GFP_KERNEL)) + goto err_cleanup; + + if (register_shrinker(&journal->j_shrinker)) { + percpu_counter_destroy(&journal->j_checkpoint_jh_count); + goto err_cleanup; + } return journal; err_cleanup: + brelse(journal->j_sb_buffer); kfree(journal->j_wbuf); jbd2_journal_destroy_revoke(journal); kfree(journal); @@ -2051,93 +2107,6 @@ recovery_error: } /** - * jbd2_journal_shrink_scan() - * - * Scan the checkpointed buffer on the checkpoint list and release the - * journal_head. - */ -static unsigned long jbd2_journal_shrink_scan(struct shrinker *shrink, - struct shrink_control *sc) -{ - journal_t *journal = container_of(shrink, journal_t, j_shrinker); - unsigned long nr_to_scan = sc->nr_to_scan; - unsigned long nr_shrunk; - unsigned long count; - - count = percpu_counter_read_positive(&journal->j_jh_shrink_count); - trace_jbd2_shrink_scan_enter(journal, sc->nr_to_scan, count); - - nr_shrunk = jbd2_journal_shrink_checkpoint_list(journal, &nr_to_scan); - - count = percpu_counter_read_positive(&journal->j_jh_shrink_count); - trace_jbd2_shrink_scan_exit(journal, nr_to_scan, nr_shrunk, count); - - return nr_shrunk; -} - -/** - * jbd2_journal_shrink_count() - * - * Count the number of checkpoint buffers on the checkpoint list. - */ -static unsigned long jbd2_journal_shrink_count(struct shrinker *shrink, - struct shrink_control *sc) -{ - journal_t *journal = container_of(shrink, journal_t, j_shrinker); - unsigned long count; - - count = percpu_counter_read_positive(&journal->j_jh_shrink_count); - trace_jbd2_shrink_count(journal, sc->nr_to_scan, count); - - return count; -} - -/** - * jbd2_journal_register_shrinker() - * @journal: Journal to act on. - * - * Init a percpu counter to record the checkpointed buffers on the checkpoint - * list and register a shrinker to release their journal_head. - */ -int jbd2_journal_register_shrinker(journal_t *journal) -{ - int err; - - journal->j_shrink_transaction = NULL; - - err = percpu_counter_init(&journal->j_jh_shrink_count, 0, GFP_KERNEL); - if (err) - return err; - - journal->j_shrinker.scan_objects = jbd2_journal_shrink_scan; - journal->j_shrinker.count_objects = jbd2_journal_shrink_count; - journal->j_shrinker.seeks = DEFAULT_SEEKS; - journal->j_shrinker.batch = journal->j_max_transaction_buffers; - - err = register_shrinker(&journal->j_shrinker); - if (err) { - percpu_counter_destroy(&journal->j_jh_shrink_count); - return err; - } - - return 0; -} -EXPORT_SYMBOL(jbd2_journal_register_shrinker); - -/** - * jbd2_journal_unregister_shrinker() - * @journal: Journal to act on. - * - * Unregister the checkpointed buffer shrinker and destroy the percpu counter. - */ -void jbd2_journal_unregister_shrinker(journal_t *journal) -{ - percpu_counter_destroy(&journal->j_jh_shrink_count); - unregister_shrinker(&journal->j_shrinker); -} -EXPORT_SYMBOL(jbd2_journal_unregister_shrinker); - -/** * jbd2_journal_destroy() - Release a journal_t structure. * @journal: Journal to act on. * @@ -2209,8 +2178,10 @@ int jbd2_journal_destroy(journal_t *journal) brelse(journal->j_sb_buffer); } - jbd2_journal_unregister_shrinker(journal); - + if (journal->j_shrinker.flags & SHRINKER_REGISTERED) { + percpu_counter_destroy(&journal->j_checkpoint_jh_count); + unregister_shrinker(&journal->j_shrinker); + } if (journal->j_proc_entry) jbd2_stats_proc_exit(journal); iput(journal->j_inode); |