Commit c601e5d7 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Can now block journal activity without closing cur entry 



Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent c80f33b7

fs/bcachefs/journal.c

+42 −2
Original line number Diff line number Diff line
@@ -217,6 +217,12 @@ void bch2_journal_buf_put_final(struct journal *j, u64 seq) 
	if (__bch2_journal_pin_put(j, seq))

		bch2_journal_reclaim_fast(j);

	bch2_journal_do_writes(j);



	/*

	 * for __bch2_next_write_buffer_flush_journal_buf(), when quiescing an

	 * open journal entry

	 */

	wake_up(&j->wait);

}



/*
@@ -251,6 +257,9 @@ static void __journal_entry_close(struct journal *j, unsigned closed_val, bool t 
	if (!__journal_entry_is_open(old))

		return;



	if (old.cur_entry_offset == JOURNAL_ENTRY_BLOCKED_VAL)

		old.cur_entry_offset = j->cur_entry_offset_if_blocked;



	/* Close out old buffer: */

	buf->data->u64s		= cpu_to_le32(old.cur_entry_offset);
@@ -868,16 +877,44 @@ int bch2_journal_meta(struct journal *j) 
void bch2_journal_unblock(struct journal *j)

{

	spin_lock(&j->lock);

	j->blocked--;

	if (!--j->blocked &&

	    j->cur_entry_offset_if_blocked < JOURNAL_ENTRY_CLOSED_VAL &&

	    j->reservations.cur_entry_offset == JOURNAL_ENTRY_BLOCKED_VAL) {

		union journal_res_state old, new;



		old.v = atomic64_read(&j->reservations.counter);

		do {

			new.v = old.v;

			new.cur_entry_offset = j->cur_entry_offset_if_blocked;

		} while (!atomic64_try_cmpxchg(&j->reservations.counter, &old.v, new.v));

	}

	spin_unlock(&j->lock);



	journal_wake(j);

}



static void __bch2_journal_block(struct journal *j)

{

	if (!j->blocked++) {

		union journal_res_state old, new;



		old.v = atomic64_read(&j->reservations.counter);

		do {

			j->cur_entry_offset_if_blocked = old.cur_entry_offset;



			if (j->cur_entry_offset_if_blocked >= JOURNAL_ENTRY_CLOSED_VAL)

				break;



			new.v = old.v;

			new.cur_entry_offset = JOURNAL_ENTRY_BLOCKED_VAL;

		} while (!atomic64_try_cmpxchg(&j->reservations.counter, &old.v, new.v));

	}

}



void bch2_journal_block(struct journal *j)

{

	spin_lock(&j->lock);

	j->blocked++;

	__bch2_journal_block(j);

	spin_unlock(&j->lock);



	journal_quiesce(j);
@@ -1481,6 +1518,9 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j) 
	case JOURNAL_ENTRY_CLOSED_VAL:

		prt_printf(out, "closed\n");

		break;

	case JOURNAL_ENTRY_BLOCKED_VAL:

		prt_printf(out, "blocked\n");

		break;

	default:

		prt_printf(out, "%u/%u\n", s.cur_entry_offset, j->cur_entry_u64s);

		break;

fs/bcachefs/journal.h

+2 −1
Original line number Diff line number Diff line
@@ -285,7 +285,8 @@ static inline void bch2_journal_buf_put(struct journal *j, unsigned idx, u64 seq 
		spin_lock(&j->lock);

		bch2_journal_buf_put_final(j, seq);

		spin_unlock(&j->lock);

	}

	} else if (unlikely(s.cur_entry_offset == JOURNAL_ENTRY_BLOCKED_VAL))

		wake_up(&j->wait);

}



/*

fs/bcachefs/journal_types.h

+2 −0
Original line number Diff line number Diff line
@@ -112,6 +112,7 @@ union journal_res_state { 
 */

#define JOURNAL_ENTRY_OFFSET_MAX	((1U << 20) - 1)



#define JOURNAL_ENTRY_BLOCKED_VAL	(JOURNAL_ENTRY_OFFSET_MAX - 2)

#define JOURNAL_ENTRY_CLOSED_VAL	(JOURNAL_ENTRY_OFFSET_MAX - 1)

#define JOURNAL_ENTRY_ERROR_VAL		(JOURNAL_ENTRY_OFFSET_MAX)
@@ -193,6 +194,7 @@ struct journal { 
	 * insufficient devices:

	 */

	enum journal_errors	cur_entry_error;

	unsigned		cur_entry_offset_if_blocked;



	unsigned		buf_size_want;

	/*