bcachefs: Better journal tracepoints

Factor out bch2_journal_bufs_to_text(), and use it in the
journal_entry_full() tracepoint; when we can't get a journal reservation
we need to know the outstanding journal entry sizes to know if the
problem is due to excessive flushing.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2024-01-15 17:59:51 -05:00
parent 4ae016607b
commit e6a2566f7a
2 changed files with 79 additions and 60 deletions

View File

@ -27,6 +27,47 @@ static const char * const bch2_journal_errors[] = {
NULL
};
static void bch2_journal_buf_to_text(struct printbuf *out, struct journal *j, u64 seq)
{
union journal_res_state s = READ_ONCE(j->reservations);
unsigned i = seq & JOURNAL_BUF_MASK;
struct journal_buf *buf = j->buf + i;
prt_printf(out, "seq:");
prt_tab(out);
prt_printf(out, "%llu", seq);
prt_newline(out);
printbuf_indent_add(out, 2);
prt_printf(out, "refcount:");
prt_tab(out);
prt_printf(out, "%u", journal_state_count(s, i));
prt_newline(out);
prt_printf(out, "size:");
prt_tab(out);
prt_human_readable_u64(out, vstruct_bytes(buf->data));
prt_newline(out);
prt_printf(out, "expires");
prt_tab(out);
prt_printf(out, "%li jiffies", buf->expires - jiffies);
prt_newline(out);
printbuf_indent_sub(out, 2);
}
static void bch2_journal_bufs_to_text(struct printbuf *out, struct journal *j)
{
if (!out->nr_tabstops)
printbuf_tabstop_push(out, 24);
for (u64 seq = journal_last_unwritten_seq(j);
seq <= journal_cur_seq(j);
seq++)
bch2_journal_buf_to_text(out, j, seq);
}
static inline bool journal_seq_unwritten(struct journal *j, u64 seq)
{
return seq > j->seq_ondisk;
@ -156,7 +197,7 @@ void bch2_journal_buf_put_final(struct journal *j, u64 seq, bool write)
* We don't close a journal_buf until the next journal_buf is finished writing,
* and can be opened again - this also initializes the next journal_buf:
*/
static void __journal_entry_close(struct journal *j, unsigned closed_val)
static void __journal_entry_close(struct journal *j, unsigned closed_val, bool trace)
{
struct bch_fs *c = container_of(j, struct bch_fs, journal);
struct journal_buf *buf = journal_cur_buf(j);
@ -185,7 +226,17 @@ static void __journal_entry_close(struct journal *j, unsigned closed_val)
/* Close out old buffer: */
buf->data->u64s = cpu_to_le32(old.cur_entry_offset);
trace_journal_entry_close(c, vstruct_bytes(buf->data));
if (trace_journal_entry_close_enabled() && trace) {
struct printbuf pbuf = PRINTBUF;
pbuf.atomic++;
prt_str(&pbuf, "entry size: ");
prt_human_readable_u64(&pbuf, vstruct_bytes(buf->data));
prt_newline(&pbuf);
bch2_prt_task_backtrace(&pbuf, current, 1);
trace_journal_entry_close(c, pbuf.buf);
printbuf_exit(&pbuf);
}
sectors = vstruct_blocks_plus(buf->data, c->block_bits,
buf->u64s_reserved) << c->block_bits;
@ -225,7 +276,7 @@ static void __journal_entry_close(struct journal *j, unsigned closed_val)
void bch2_journal_halt(struct journal *j)
{
spin_lock(&j->lock);
__journal_entry_close(j, JOURNAL_ENTRY_ERROR_VAL);
__journal_entry_close(j, JOURNAL_ENTRY_ERROR_VAL, true);
if (!j->err_seq)
j->err_seq = journal_cur_seq(j);
journal_wake(j);
@ -239,7 +290,7 @@ static bool journal_entry_want_write(struct journal *j)
/* Don't close it yet if we already have a write in flight: */
if (ret)
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL);
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL, true);
else if (nr_unwritten_journal_entries(j)) {
struct journal_buf *buf = journal_cur_buf(j);
@ -406,7 +457,7 @@ static void journal_write_work(struct work_struct *work)
if (delta > 0)
mod_delayed_work(c->io_complete_wq, &j->write_work, delta);
else
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL);
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL, true);
unlock:
spin_unlock(&j->lock);
}
@ -463,13 +514,21 @@ retry:
buf->buf_size < JOURNAL_ENTRY_SIZE_MAX)
j->buf_size_want = max(j->buf_size_want, buf->buf_size << 1);
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL);
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL, false);
ret = journal_entry_open(j);
if (ret == JOURNAL_ERR_max_in_flight) {
track_event_change(&c->times[BCH_TIME_blocked_journal_max_in_flight],
&j->max_in_flight_start, true);
trace_and_count(c, journal_entry_full, c);
if (trace_journal_entry_full_enabled()) {
struct printbuf buf = PRINTBUF;
buf.atomic++;
bch2_journal_bufs_to_text(&buf, j);
trace_journal_entry_full(c, buf.buf);
printbuf_exit(&buf);
}
count_event(c, journal_entry_full);
}
unlock:
can_discard = j->can_discard;
@ -549,7 +608,7 @@ void bch2_journal_entry_res_resize(struct journal *j,
/*
* Not enough room in current journal entry, have to flush it:
*/
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL);
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL, true);
} else {
journal_cur_buf(j)->u64s_reserved += d;
}
@ -606,7 +665,7 @@ recheck_need_open:
struct journal_res res = { 0 };
if (journal_entry_is_open(j))
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL);
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL, true);
spin_unlock(&j->lock);
@ -786,7 +845,7 @@ static struct journal_buf *__bch2_next_write_buffer_flush_journal_buf(struct jou
if (buf->need_flush_to_write_buffer) {
if (seq == journal_cur_seq(j))
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL);
__journal_entry_close(j, JOURNAL_ENTRY_CLOSED_VAL, true);
union journal_res_state s;
s.v = atomic64_read_acquire(&j->reservations.counter);
@ -1339,35 +1398,9 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j)
}
prt_newline(out);
for (u64 seq = journal_cur_seq(j);
seq >= journal_last_unwritten_seq(j);
--seq) {
unsigned i = seq & JOURNAL_BUF_MASK;
prt_printf(out, "unwritten entry:");
prt_tab(out);
prt_printf(out, "%llu", seq);
prt_newline(out);
printbuf_indent_add(out, 2);
prt_printf(out, "refcount:");
prt_tab(out);
prt_printf(out, "%u", journal_state_count(s, i));
prt_newline(out);
prt_printf(out, "sectors:");
prt_tab(out);
prt_printf(out, "%u", j->buf[i].sectors);
prt_newline(out);
prt_printf(out, "expires");
prt_tab(out);
prt_printf(out, "%li jiffies", j->buf[i].expires - jiffies);
prt_newline(out);
printbuf_indent_sub(out, 2);
}
prt_printf(out, "unwritten entries:");
prt_newline(out);
bch2_journal_bufs_to_text(out, j);
prt_printf(out,
"replay done:\t\t%i\n",

View File

@ -46,7 +46,7 @@ DECLARE_EVENT_CLASS(fs_str,
__assign_str(str, str);
),
TP_printk("%d,%d %s", MAJOR(__entry->dev), MINOR(__entry->dev), __get_str(str))
TP_printk("%d,%d\n%s", MAJOR(__entry->dev), MINOR(__entry->dev), __get_str(str))
);
DECLARE_EVENT_CLASS(trans_str,
@ -273,28 +273,14 @@ DEFINE_EVENT(bch_fs, journal_full,
TP_ARGS(c)
);
DEFINE_EVENT(bch_fs, journal_entry_full,
TP_PROTO(struct bch_fs *c),
TP_ARGS(c)
DEFINE_EVENT(fs_str, journal_entry_full,
TP_PROTO(struct bch_fs *c, const char *str),
TP_ARGS(c, str)
);
TRACE_EVENT(journal_entry_close,
TP_PROTO(struct bch_fs *c, unsigned bytes),
TP_ARGS(c, bytes),
TP_STRUCT__entry(
__field(dev_t, dev )
__field(u32, bytes )
),
TP_fast_assign(
__entry->dev = c->dev;
__entry->bytes = bytes;
),
TP_printk("%d,%d entry bytes %u",
MAJOR(__entry->dev), MINOR(__entry->dev),
__entry->bytes)
DEFINE_EVENT(fs_str, journal_entry_close,
TP_PROTO(struct bch_fs *c, const char *str),
TP_ARGS(c, str)
);
DEFINE_EVENT(bio, journal_write,