diff mbox series

[17/20] bcache: support storing bcache journal into NVDIMM meta device

Message ID 20210210050742.31237-18-colyli@suse.de (mailing list archive)
State New, archived
Headers show
Series bcache patches for Linux v5.12 | expand

Commit Message

Coly Li Feb. 10, 2021, 5:07 a.m. UTC
This patch implements two methods to store bcache journal to,
1) __journal_write_unlocked() for block interface device
   The latency method to compose bio and issue the jset bio to cache
   device (e.g. SSD). c->journal.key.ptr[0] indicates the LBA on cache
   device to store the journal jset.
2) __journal_nvdimm_write_unlocked() for memory interface NVDIMM
   Use memory interface to access NVDIMM pages and store the jset by
   memcpy_flushcache(). c->journal.key.ptr[0] indicates the linear
   address from the NVDIMM pages to store the journal jset.

For lagency configuration without NVDIMM meta device, journal I/O is
handled by __journal_write_unlocked() with existing code logic. If the
NVDIMM meta device is used (by bcache-tools), the journal I/O will
be handled by __journal_nvdimm_write_unlocked() and go into the NVDIMM
pages.

And when NVDIMM meta device is used, sb.d[] stores the linear addresses
from NVDIMM pages (no more bucket index), in journal_reclaim() the
journaling location in c->journal.key.ptr[0] should also be updated by
linear address from NVDIMM pages (no more LBA combined by sectors offset
and bucket index).

Signed-off-by: Coly Li <colyli@suse.de>
Cc: Jianpeng Ma <jianpeng.ma@intel.com>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
---
 drivers/md/bcache/journal.c | 111 ++++++++++++++++++++++++------------
 1 file changed, 75 insertions(+), 36 deletions(-)

Comments

Nix Feb. 18, 2021, 9:21 p.m. UTC | #1
On 10 Feb 2021, Coly Li uttered the following:

> This patch implements two methods to store bcache journal to,
> 1) __journal_write_unlocked() for block interface device
>    The latency method to compose bio and issue the jset bio to cache

Is this really 'latency'? I suspect from other patches it should be
'legacy', which is surely not true unless the expectation is that soon
all bcache users will have NVDIMMs and can use the other path (surely
not).

> For lagency

This non-word should possibly be 'legacy' too?
diff mbox series

Patch

diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 1f16d8e497cf..b242fcb47ce2 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -596,6 +596,8 @@  static void do_journal_discard(struct cache *ca)
 		return;
 	}
 
+	BUG_ON(bch_has_feature_nvdimm_meta(&ca->sb));
+
 	switch (atomic_read(&ja->discard_in_flight)) {
 	case DISCARD_IN_FLIGHT:
 		return;
@@ -661,9 +663,13 @@  static void journal_reclaim(struct cache_set *c)
 		goto out;
 
 	ja->cur_idx = next;
-	k->ptr[0] = MAKE_PTR(0,
-			     bucket_to_sector(c, ca->sb.d[ja->cur_idx]),
-			     ca->sb.nr_this_dev);
+	if (!bch_has_feature_nvdimm_meta(&ca->sb))
+		k->ptr[0] = MAKE_PTR(0,
+			bucket_to_sector(c, ca->sb.d[ja->cur_idx]),
+			ca->sb.nr_this_dev);
+	else
+		k->ptr[0] = ca->sb.d[ja->cur_idx];
+
 	atomic_long_inc(&c->reclaimed_journal_buckets);
 
 	bkey_init(k);
@@ -729,46 +735,21 @@  static void journal_write_unlock(struct closure *cl)
 	spin_unlock(&c->journal.lock);
 }
 
-static void journal_write_unlocked(struct closure *cl)
+
+static void __journal_write_unlocked(struct cache_set *c)
 	__releases(c->journal.lock)
 {
-	struct cache_set *c = container_of(cl, struct cache_set, journal.io);
-	struct cache *ca = c->cache;
-	struct journal_write *w = c->journal.cur;
 	struct bkey *k = &c->journal.key;
-	unsigned int i, sectors = set_blocks(w->data, block_bytes(ca)) *
-		ca->sb.block_size;
-
+	struct journal_write *w = c->journal.cur;
+	struct closure *cl = &c->journal.io;
+	struct cache *ca = c->cache;
 	struct bio *bio;
 	struct bio_list list;
+	unsigned int i, sectors = set_blocks(w->data, block_bytes(ca)) *
+		ca->sb.block_size;
 
 	bio_list_init(&list);
 
-	if (!w->need_write) {
-		closure_return_with_destructor(cl, journal_write_unlock);
-		return;
-	} else if (journal_full(&c->journal)) {
-		journal_reclaim(c);
-		spin_unlock(&c->journal.lock);
-
-		btree_flush_write(c);
-		continue_at(cl, journal_write, bch_journal_wq);
-		return;
-	}
-
-	c->journal.blocks_free -= set_blocks(w->data, block_bytes(ca));
-
-	w->data->btree_level = c->root->level;
-
-	bkey_copy(&w->data->btree_root, &c->root->key);
-	bkey_copy(&w->data->uuid_bucket, &c->uuid_bucket);
-
-	w->data->prio_bucket[ca->sb.nr_this_dev] = ca->prio_buckets[0];
-	w->data->magic		= jset_magic(&ca->sb);
-	w->data->version	= BCACHE_JSET_VERSION;
-	w->data->last_seq	= last_seq(&c->journal);
-	w->data->csum		= csum_set(w->data);
-
 	for (i = 0; i < KEY_PTRS(k); i++) {
 		ca = PTR_CACHE(c, k, i);
 		bio = &ca->journal.bio;
@@ -793,7 +774,6 @@  static void journal_write_unlocked(struct closure *cl)
 
 		ca->journal.seq[ca->journal.cur_idx] = w->data->seq;
 	}
-
 	/* If KEY_PTRS(k) == 0, this jset gets lost in air */
 	BUG_ON(i == 0);
 
@@ -805,6 +785,65 @@  static void journal_write_unlocked(struct closure *cl)
 
 	while ((bio = bio_list_pop(&list)))
 		closure_bio_submit(c, bio, cl);
+}
+
+static void __journal_nvdimm_write_unlocked(struct cache_set *c)
+	__releases(c->journal.lock)
+{
+	struct journal_write *w = c->journal.cur;
+	struct cache *ca = c->cache;
+	unsigned int sectors;
+
+	sectors = set_blocks(w->data, block_bytes(ca)) * ca->sb.block_size;
+	atomic_long_add(sectors, &ca->meta_sectors_written);
+
+	memcpy_flushcache((void *)c->journal.key.ptr[0], w->data, sectors << 9);
+
+	c->journal.key.ptr[0] += sectors << 9;
+	ca->journal.seq[ca->journal.cur_idx] = w->data->seq;
+
+	atomic_dec_bug(&fifo_back(&c->journal.pin));
+	bch_journal_next(&c->journal);
+	journal_reclaim(c);
+
+	spin_unlock(&c->journal.lock);
+}
+
+static void journal_write_unlocked(struct closure *cl)
+{
+	struct cache_set *c = container_of(cl, struct cache_set, journal.io);
+	struct cache *ca = c->cache;
+	struct journal_write *w = c->journal.cur;
+
+	if (!w->need_write) {
+		closure_return_with_destructor(cl, journal_write_unlock);
+		return;
+	} else if (journal_full(&c->journal)) {
+		journal_reclaim(c);
+		spin_unlock(&c->journal.lock);
+
+		btree_flush_write(c);
+		continue_at(cl, journal_write, bch_journal_wq);
+		return;
+	}
+
+	c->journal.blocks_free -= set_blocks(w->data, block_bytes(ca));
+
+	w->data->btree_level = c->root->level;
+
+	bkey_copy(&w->data->btree_root, &c->root->key);
+	bkey_copy(&w->data->uuid_bucket, &c->uuid_bucket);
+
+	w->data->prio_bucket[ca->sb.nr_this_dev] = ca->prio_buckets[0];
+	w->data->magic		= jset_magic(&ca->sb);
+	w->data->version	= BCACHE_JSET_VERSION;
+	w->data->last_seq	= last_seq(&c->journal);
+	w->data->csum		= csum_set(w->data);
+
+	if (!bch_has_feature_nvdimm_meta(&ca->sb))
+		__journal_write_unlocked(c);
+	else
+		__journal_nvdimm_write_unlocked(c);
 
 	continue_at(cl, journal_write_done, NULL);
 }