This patch renames original bch_mca_scan() to __bch_mca_scan() and add
the third parameter "bool reap_flush". The parameter reap_flush is used
when calling mca_reap() inside __bch_mca_scan() to indicate weather
mca_reap() should flush or skip dirty btree node cache.
bch_mca_scan() still exists but it changes to a wrapper of,
{return __bch_mca_scan(shrink, sc, false);}
bch_mca_scan() won't reap dirty btree node cache, by this change, it is
possible to reap and shrink dirty btree node cache when calling
__bch_mca_scan() with reap_flush set to true.
This is necessary for following changes which control memory consumption
of bcache btree node cache by throttling regular I/O requests.
Signed-off-by: Coly Li <colyli@xxxxxxx>
---
drivers/md/bcache/btree.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index fa872df4e770..b37405aedf6e 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -699,8 +699,9 @@ static int mca_reap(struct btree *b, unsigned int min_order, bool flush)
return -ENOMEM;
}
-static unsigned long bch_mca_scan(struct shrinker *shrink,
- struct shrink_control *sc)
+static unsigned long __bch_mca_scan(struct shrinker *shrink,
+ struct shrink_control *sc,
+ bool reap_flush)
{
struct cache_set *c = container_of(shrink, struct cache_set, shrink);
struct btree *b, *t;
@@ -738,7 +739,7 @@ static unsigned long bch_mca_scan(struct shrinker *shrink,
if (nr <= 0)
goto out;
- if (!mca_reap(b, 0, false)) {
+ if (!mca_reap(b, 0, reap_flush)) {
mca_data_free(b);
rw_unlock(true, b);
freed++;
@@ -751,7 +752,7 @@ static unsigned long bch_mca_scan(struct shrinker *shrink,
if (nr <= 0 || i >= btree_cache_used)
goto out;
- if (!mca_reap(b, 0, false)) {
+ if (!mca_reap(b, 0, reap_flush)) {
mca_bucket_free(b);
mca_data_free(b);
rw_unlock(true, b);
@@ -766,6 +767,12 @@ static unsigned long bch_mca_scan(struct shrinker *shrink,
return freed * c->btree_pages;
}
+static unsigned long bch_mca_scan(struct shrinker *shrink,
+ struct shrink_control *sc)
+{
+ return __bch_mca_scan(shrink, sc, false);
+}
+
static unsigned long bch_mca_count(struct shrinker *shrink,
struct shrink_control *sc)
{
--
2.16.4
