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| author | Coly Li <colyli@suse.de> | 2019-11-13 16:03:22 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-11-13 15:42:50 -0700 |
| commit | 5dccefd3ea0b33cf3e5a45cbccc7e0bf22791655 (patch) | |
| tree | ac6e1c64a1899967193bed81559b31838d4f5b9a /drivers/md/bcache/btree.c | |
| parent | 84c529aea182939e68f618ed9813740c9165c7eb (diff) | |
| download | linux-5dccefd3ea0b33cf3e5a45cbccc7e0bf22791655.tar.bz2 | |
bcache: add code comments in bch_btree_leaf_dirty()
This patch adds code comments in bch_btree_leaf_dirty() to explain
why w->journal should always reference the eldest journal pin of
all the writing bkeys in the btree node. To make the bcache journal
code to be easier to be understood.
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/md/bcache/btree.c')
| -rw-r--r-- | drivers/md/bcache/btree.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index 39d7fc1ef1ee..48e33ee0d876 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -569,6 +569,11 @@ static void bch_btree_leaf_dirty(struct btree *b, atomic_t *journal_ref) set_btree_node_dirty(b); + /* + * w->journal is always the oldest journal pin of all bkeys + * in the leaf node, to make sure the oldest jset seq won't + * be increased before this btree node is flushed. + */ if (journal_ref) { if (w->journal && journal_pin_cmp(b->c, w->journal, journal_ref)) { |