From 80396a47490936f73729548310ad60e9f5df61c9 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Thu, 2 Nov 2023 21:01:25 -0400 Subject: bcachefs: Break up bch2_journal_write() Split up bch2_journal_write() to simplify locking: - bch2_journal_write_pick_flush(), which needs j->lock - bch2_journal_write_prep, which operates on the journal buffer to be written and will need the upcoming buf_lock for synchronization with the btree write buffer flush path Signed-off-by: Kent Overstreet --- fs/bcachefs/journal_io.c | 163 ++++++++++++++++++++++++++--------------------- 1 file changed, 92 insertions(+), 71 deletions(-) (limited to 'fs/bcachefs/journal_io.c') diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c index 65878542940d..392e90d4d4fb 100644 --- a/fs/bcachefs/journal_io.c +++ b/fs/bcachefs/journal_io.c @@ -1724,68 +1724,18 @@ static void bch2_journal_entries_postprocess(struct bch_fs *c, struct jset *jset jset->u64s = cpu_to_le32((u64 *) prev - jset->_data); } -void bch2_journal_write(struct closure *cl) +static int bch2_journal_write_prep(struct journal *j, struct journal_buf *w) { - struct journal *j = container_of(cl, struct journal, io); struct bch_fs *c = container_of(j, struct bch_fs, journal); - struct bch_dev *ca; - struct journal_buf *w = journal_last_unwritten_buf(j); - struct bch_replicas_padded replicas; struct jset_entry *start, *end; struct jset *jset; - struct bio *bio; - struct printbuf journal_debug_buf = PRINTBUF; + unsigned sectors, bytes, u64s; bool validate_before_checksum = false; - unsigned i, sectors, bytes, u64s, nr_rw_members = 0; int ret; - BUG_ON(BCH_SB_CLEAN(c->disk_sb.sb)); - journal_buf_realloc(j, w); jset = w->data; - j->write_start_time = local_clock(); - - spin_lock(&j->lock); - - /* - * If the journal is in an error state - we did an emergency shutdown - - * we prefer to continue doing journal writes. We just mark them as - * noflush so they'll never be used, but they'll still be visible by the - * list_journal tool - this helps in debugging. - * - * There's a caveat: the first journal write after marking the - * superblock dirty must always be a flush write, because on startup - * from a clean shutdown we didn't necessarily read the journal and the - * new journal write might overwrite whatever was in the journal - * previously - we can't leave the journal without any flush writes in - * it. - * - * So if we're in an error state, and we're still starting up, we don't - * write anything at all. - */ - if (!test_bit(JOURNAL_NEED_FLUSH_WRITE, &j->flags) && - (bch2_journal_error(j) || - w->noflush || - (!w->must_flush && - (jiffies - j->last_flush_write) < msecs_to_jiffies(c->opts.journal_flush_delay) && - test_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags)))) { - w->noflush = true; - SET_JSET_NO_FLUSH(jset, true); - jset->last_seq = 0; - w->last_seq = 0; - - j->nr_noflush_writes++; - } else if (!bch2_journal_error(j)) { - j->last_flush_write = jiffies; - j->nr_flush_writes++; - clear_bit(JOURNAL_NEED_FLUSH_WRITE, &j->flags); - } else { - spin_unlock(&j->lock); - goto err; - } - spin_unlock(&j->lock); - /* * New btree roots are set by journalling them; when the journal entry * gets written we have to propagate them to c->btree_roots @@ -1816,7 +1766,7 @@ void bch2_journal_write(struct closure *cl) bch2_fs_fatal_error(c, "aieeee! journal write overran available space, %zu > %u (extra %u reserved %u/%u)", vstruct_bytes(jset), w->sectors << 9, u64s, w->u64s_reserved, j->entry_u64s_reserved); - goto err; + return -EINVAL; } jset->magic = cpu_to_le64(jset_magic(c)); @@ -1835,37 +1785,115 @@ void bch2_journal_write(struct closure *cl) validate_before_checksum = true; if (validate_before_checksum && - jset_validate(c, NULL, jset, 0, WRITE)) - goto err; + (ret = jset_validate(c, NULL, jset, 0, WRITE))) + return ret; ret = bch2_encrypt(c, JSET_CSUM_TYPE(jset), journal_nonce(jset), jset->encrypted_start, vstruct_end(jset) - (void *) jset->encrypted_start); if (bch2_fs_fatal_err_on(ret, c, "error decrypting journal entry: %i", ret)) - goto err; + return ret; jset->csum = csum_vstruct(c, JSET_CSUM_TYPE(jset), journal_nonce(jset), jset); if (!validate_before_checksum && - jset_validate(c, NULL, jset, 0, WRITE)) - goto err; + (ret = jset_validate(c, NULL, jset, 0, WRITE))) + return ret; memset((void *) jset + bytes, 0, (sectors << 9) - bytes); + return 0; +} + +static int bch2_journal_write_pick_flush(struct journal *j, struct journal_buf *w) +{ + struct bch_fs *c = container_of(j, struct bch_fs, journal); + int error = bch2_journal_error(j); + + /* + * If the journal is in an error state - we did an emergency shutdown - + * we prefer to continue doing journal writes. We just mark them as + * noflush so they'll never be used, but they'll still be visible by the + * list_journal tool - this helps in debugging. + * + * There's a caveat: the first journal write after marking the + * superblock dirty must always be a flush write, because on startup + * from a clean shutdown we didn't necessarily read the journal and the + * new journal write might overwrite whatever was in the journal + * previously - we can't leave the journal without any flush writes in + * it. + * + * So if we're in an error state, and we're still starting up, we don't + * write anything at all. + */ + if (error && test_bit(JOURNAL_NEED_FLUSH_WRITE, &j->flags)) + return -EIO; + + if (error || + w->noflush || + (!w->must_flush && + (jiffies - j->last_flush_write) < msecs_to_jiffies(c->opts.journal_flush_delay) && + test_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags))) { + w->noflush = true; + SET_JSET_NO_FLUSH(w->data, true); + w->data->last_seq = 0; + w->last_seq = 0; + + j->nr_noflush_writes++; + } else { + j->last_flush_write = jiffies; + j->nr_flush_writes++; + clear_bit(JOURNAL_NEED_FLUSH_WRITE, &j->flags); + } + + return 0; +} + +void bch2_journal_write(struct closure *cl) +{ + struct journal *j = container_of(cl, struct journal, io); + struct bch_fs *c = container_of(j, struct bch_fs, journal); + struct bch_dev *ca; + struct journal_buf *w = journal_last_unwritten_buf(j); + struct bch_replicas_padded replicas; + struct bio *bio; + struct printbuf journal_debug_buf = PRINTBUF; + unsigned i, nr_rw_members = 0; + int ret; + + BUG_ON(BCH_SB_CLEAN(c->disk_sb.sb)); + + j->write_start_time = local_clock(); -retry_alloc: spin_lock(&j->lock); - ret = journal_write_alloc(j, w); + ret = bch2_journal_write_pick_flush(j, w); + spin_unlock(&j->lock); + if (ret) + goto err; + + ret = bch2_journal_write_prep(j, w); + if (ret) + goto err; + + while (1) { + spin_lock(&j->lock); + ret = journal_write_alloc(j, w); + if (!ret || !j->can_discard) + break; - if (ret && j->can_discard) { spin_unlock(&j->lock); bch2_journal_do_discards(j); - goto retry_alloc; } - if (ret) + if (ret) { __bch2_journal_debug_to_text(&journal_debug_buf, j); + spin_unlock(&j->lock); + bch_err(c, "Unable to allocate journal write:\n%s", + journal_debug_buf.buf); + printbuf_exit(&journal_debug_buf); + goto err; + } /* * write is allocated, no longer need to account for it in @@ -1880,13 +1908,6 @@ retry_alloc: bch2_journal_space_available(j); spin_unlock(&j->lock); - if (ret) { - bch_err(c, "Unable to allocate journal write:\n%s", - journal_debug_buf.buf); - printbuf_exit(&journal_debug_buf); - goto err; - } - w->devs_written = bch2_bkey_devs(bkey_i_to_s_c(&w->key)); if (c->opts.nochanges) @@ -1908,7 +1929,7 @@ retry_alloc: if (ret) goto err; - if (!JSET_NO_FLUSH(jset) && w->separate_flush) { + if (!JSET_NO_FLUSH(w->data) && w->separate_flush) { for_each_rw_member(ca, c, i) { percpu_ref_get(&ca->io_ref); -- cgit v1.2.3