Commit fb64f3fd authored by Kent Overstreet's avatar Kent Overstreet Committed by Kent Overstreet
Browse files

bcachefs: BCH_JSET_ENTRY_log 



Add a journal entry type for logging messages, and add an option to use
it to log the transaction name - this makes for a very handy debugging
tool, as with it we can use the 'bcachefs list_journal' command to see
not only what updates were done, but what was doing them.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
parent f0f41a6d

fs/bcachefs/bcachefs_format.h

+8 −1
Original line number Diff line number Diff line
@@ -1430,6 +1430,7 @@ LE64_BITMASK(BCH_SB_INODES_USE_KEY_CACHE,struct bch_sb, flags[3], 29, 30); 
LE64_BITMASK(BCH_SB_JOURNAL_FLUSH_DELAY,struct bch_sb, flags[3], 30, 62);

LE64_BITMASK(BCH_SB_JOURNAL_FLUSH_DISABLED,struct bch_sb, flags[3], 62, 63);

LE64_BITMASK(BCH_SB_JOURNAL_RECLAIM_DELAY,struct bch_sb, flags[4], 0, 32);

LE64_BITMASK(BCH_SB_JOURNAL_TRANSACTION_NAMES,struct bch_sb, flags[4], 32, 33);



/*

 * Features:
@@ -1667,7 +1668,8 @@ static inline __u64 __bset_magic(struct bch_sb *sb) 
	x(usage,		5)		\

	x(data_usage,		6)		\

	x(clock,		7)		\

	x(dev_usage,		8)

	x(dev_usage,		8)		\

	x(log,			9)



enum {

#define x(f, nr)	BCH_JSET_ENTRY_##f	= nr,
@@ -1739,6 +1741,11 @@ struct jset_entry_dev_usage { 
	struct jset_entry_dev_usage_type d[];

} __attribute__((packed));



struct jset_entry_log {

	struct jset_entry	entry;

	u8			d[];

} __attribute__((packed));



/*

 * On disk format for a journal entry:

 * seq is monotonically increasing; every journal entry has its own unique

fs/bcachefs/btree_types.h

+1 −0
Original line number Diff line number Diff line
@@ -380,6 +380,7 @@ struct btree_trans { 
	bool			in_traverse_all:1;

	bool			restarted:1;

	bool			paths_sorted:1;

	bool			journal_transaction_names:1;

	/*

	 * For when bch2_trans_update notices we'll be splitting a compressed

	 * extent:

fs/bcachefs/btree_update_leaf.c

+39 −5
Original line number Diff line number Diff line
@@ -290,6 +290,31 @@ static inline int bch2_trans_journal_res_get(struct btree_trans *trans, 
	return ret == -EAGAIN ? BTREE_INSERT_NEED_JOURNAL_RES : ret;

}



#define JSET_ENTRY_LOG_U64s		4



static noinline void journal_transaction_name(struct btree_trans *trans)

{

	struct bch_fs *c = trans->c;

	struct jset_entry *entry = journal_res_entry(&c->journal, &trans->journal_res);

	struct jset_entry_log *l = container_of(entry, struct jset_entry_log, entry);

	unsigned u64s = JSET_ENTRY_LOG_U64s - 1;

	unsigned b, buflen = u64s * sizeof(u64);



	l->entry.u64s		= cpu_to_le16(u64s);

	l->entry.btree_id	= 0;

	l->entry.level		= 0;

	l->entry.type		= BCH_JSET_ENTRY_log;

	l->entry.pad[0]		= 0;

	l->entry.pad[1]		= 0;

	l->entry.pad[2]		= 0;

	b = snprintf(l->d, buflen, "%ps", (void *) trans->ip);

	while (b < buflen)

		l->d[b++] = '\0';



	trans->journal_res.offset	+= JSET_ENTRY_LOG_U64s;

	trans->journal_res.u64s		-= JSET_ENTRY_LOG_U64s;

}



static inline enum btree_insert_ret

btree_key_can_insert(struct btree_trans *trans,

		     struct btree *b,
@@ -451,6 +476,9 @@ bch2_trans_commit_write_locked(struct btree_trans *trans, 
				JOURNAL_RES_GET_NONBLOCK);

		if (ret)

			return ret;



		if (unlikely(trans->journal_transaction_names))

			journal_transaction_name(trans);

	} else {

		trans->journal_res.seq = c->journal.replay_journal_seq;

	}
@@ -911,6 +939,7 @@ static int bch2_trans_commit_run_triggers(struct btree_trans *trans) 


int __bch2_trans_commit(struct btree_trans *trans)

{

	struct bch_fs *c = trans->c;

	struct btree_insert_entry *i = NULL;

	unsigned u64s;

	int ret = 0;
@@ -920,15 +949,20 @@ int __bch2_trans_commit(struct btree_trans *trans) 
		goto out_reset;



	if (trans->flags & BTREE_INSERT_GC_LOCK_HELD)

		lockdep_assert_held(&trans->c->gc_lock);

		lockdep_assert_held(&c->gc_lock);



	memset(&trans->journal_preres, 0, sizeof(trans->journal_preres));



	trans->journal_u64s		= trans->extra_journal_entry_u64s;

	trans->journal_preres_u64s	= 0;



	trans->journal_transaction_names = READ_ONCE(c->opts.journal_transaction_names);



	if (trans->journal_transaction_names)

		trans->journal_u64s += JSET_ENTRY_LOG_U64s;



	if (!(trans->flags & BTREE_INSERT_NOCHECK_RW) &&

	    unlikely(!percpu_ref_tryget(&trans->c->writes))) {

	    unlikely(!percpu_ref_tryget(&c->writes))) {

		ret = bch2_trans_commit_get_rw_cold(trans);

		if (ret)

			goto out_reset;
@@ -972,7 +1006,7 @@ int __bch2_trans_commit(struct btree_trans *trans) 
	}



	if (trans->extra_journal_res) {

		ret = bch2_disk_reservation_add(trans->c, trans->disk_res,

		ret = bch2_disk_reservation_add(c, trans->disk_res,

				trans->extra_journal_res,

				(trans->flags & BTREE_INSERT_NOFAIL)

				? BCH_DISK_RESERVATION_NOFAIL : 0);
@@ -991,10 +1025,10 @@ int __bch2_trans_commit(struct btree_trans *trans) 
	if (ret)

		goto err;

out:

	bch2_journal_preres_put(&trans->c->journal, &trans->journal_preres);

	bch2_journal_preres_put(&c->journal, &trans->journal_preres);



	if (likely(!(trans->flags & BTREE_INSERT_NOCHECK_RW)))

		percpu_ref_put(&trans->c->writes);

		percpu_ref_put(&c->writes);

out_reset:

	trans_for_each_update(trans, i)

		bch2_path_put(trans, i->path, true);

fs/bcachefs/journal_io.c

+8 −0
Original line number Diff line number Diff line
@@ -478,6 +478,14 @@ static int journal_entry_validate_dev_usage(struct bch_fs *c, 
	return ret;

}



static int journal_entry_validate_log(struct bch_fs *c,

				      const char *where,

				      struct jset_entry *entry,

				      unsigned version, int big_endian, int write)

{

	return 0;

}



struct jset_entry_ops {

	int (*validate)(struct bch_fs *, const char *,

			struct jset_entry *, unsigned, int, int);

fs/bcachefs/opts.h

+5 −0
Original line number Diff line number Diff line
@@ -327,6 +327,11 @@ enum opt_type { 
	  OPT_BOOL(),							\

	  NO_SB_OPT,			false,				\

	  NULL,		"Read all journal entries, not just dirty ones")\

	x(journal_transaction_names,	u8,				\

	  OPT_FS|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,			\

	  OPT_BOOL(),							\

	  BCH_SB_JOURNAL_TRANSACTION_NAMES, true,			\

	  NULL,		"Log transaction function names in journal")	\

	x(noexcl,			u8,				\

	  OPT_FS|OPT_MOUNT,						\

	  OPT_BOOL(),							\