In r5c_finish_stripe_write_out(), R5LOG_PAYLOAD_FLUSH is append to
log->current_io.
Appending R5LOG_PAYLOAD_FLUSH in quiesce needs extra writes to
journal. To simplify the logic, we just skip R5LOG_PAYLOAD_FLUSH in
quiesce.
Even R5LOG_PAYLOAD_FLUSH supports multiple stripes per payload.
However, current implementation is one stripe per R5LOG_PAYLOAD_FLUSH,
which is simpler.
Signed-off-by: Song Liu <songliubraving@xxxxxx>
---
drivers/md/raid5-cache.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 59 insertions(+), 1 deletion(-)
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index e69f922..fd0bfea 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -590,7 +590,21 @@ static void r5l_log_endio(struct bio *bio)
mempool_free(io->meta_page, log->meta_pool);
spin_lock_irqsave(&log->io_list_lock, flags);
- __r5l_set_io_unit_state(io, IO_UNIT_IO_END);
+
+ if (list_empty(&io->stripe_list))
+ /*
+ * this io_unit only has R5LOG_PAYLOAD_FLUSH, set
+ * to IO_UNIT_STRIPE_END
+ */
+ __r5l_set_io_unit_state(io, IO_UNIT_STRIPE_END);
+ else
+ /*
+ * io_unit with R5LOG_PAYLOAD_FLUSH and also DATA/PARITY
+ * set to IO_UNIT_IO_END and wait for all stripes get
+ * handled.
+ */
+ __r5l_set_io_unit_state(io, IO_UNIT_IO_END);
+
if (log->need_cache_flush)
r5l_move_to_end_ios(log);
else
@@ -843,6 +857,41 @@ static void r5l_append_payload_page(struct r5l_log *log, struct page *page)
r5_reserve_log_entry(log, io);
}
+static void r5l_append_flush_payload(struct r5l_log *log, sector_t sect)
+{
+ struct mddev *mddev = log->rdev->mddev;
+ struct r5conf *conf = mddev->private;
+ struct r5l_io_unit *io;
+ struct r5l_payload_flush *payload;
+ int meta_size;
+
+ /*
+ * payload_flush requires extra writes to the journal.
+ * To avoid handling the extra IO in quiesce, just skip
+ * flush_payload
+ */
+ if (conf->quiesce)
+ return;
+
+ mutex_lock(&log->io_mutex);
+ meta_size = sizeof(struct r5l_payload_flush) + sizeof(__le64);
+
+ if (r5l_get_meta(log, meta_size)) {
+ mutex_unlock(&log->io_mutex);
+ return;
+ }
+
+ /* current implementation is one stripe per flush payload */
+ io = log->current_io;
+ payload = page_address(io->meta_page) + io->meta_offset;
+ payload->header.type = cpu_to_le16(R5LOG_PAYLOAD_FLUSH);
+ payload->header.flags = cpu_to_le16(0);
+ payload->size = cpu_to_le32(sizeof(__le64));
+ payload->flush_stripes[0] = cpu_to_le64(sect);
+ io->meta_offset += meta_size;
+ mutex_unlock(&log->io_mutex);
+}
+
static int r5l_log_stripe(struct r5l_log *log, struct stripe_head *sh,
int data_pages, int parity_pages)
{
@@ -1466,6 +1515,13 @@ static void r5l_do_reclaim(struct r5l_log *log)
list_empty(&log->finished_ios)))
break;
+ /*
+ * In some cases, io_unit with only R5LOG_PAYLOAD_FLUSH
+ * will stay in finished_ios list. It is necessary to
+ * complete them before quiesce.
+ */
+ r5l_complete_finished_ios(log);
+
md_wakeup_thread(log->rdev->mddev->thread);
wait_event_lock_irq(log->iounit_wait,
r5l_reclaimable_space(log) > reclaimable,
@@ -2784,6 +2840,8 @@ void r5c_finish_stripe_write_out(struct r5conf *conf,
atomic_dec(&conf->r5c_flushing_full_stripes);
atomic_dec(&conf->r5c_cached_full_stripes);
}
+
+ r5l_append_flush_payload(log, sh->sector);
}
int
--
2.9.3
--
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