[PATCH V2] lightnvm: pblk: take bitmap alloc. out of critical section

[PATCH V2] lightnvm: pblk: take bitmap alloc. out of critical section

[Javier González]

Changes since V1 - from Matias:
 - rename a function to line__reinit
 - propagate error code
 - improve commit message

Javier González (1):
  lightnvm: pblk: take bitmap alloc. out of critical section

 drivers/lightnvm/pblk-core.c | 97 +++++++++++++++++++++++++-------------------
 1 file changed, 56 insertions(+), 41 deletions(-)

-- 
2.7.4

[PATCH] lightnvm: pblk: take bitmap alloc. out of critical section

[Javier González]

pblk allocates line bitmaps within the line lock unnecessarily. In order
to take pressure out of the fast patch, allocate line bitmaps outside
of this lock and refactor accordingly.

Signed-off-by: Javier González <javier@cnexlabs.com>
---
 drivers/lightnvm/pblk-core.c | 97 +++++++++++++++++++++++++-------------------
 1 file changed, 56 insertions(+), 41 deletions(-)

diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
index 5f960a6609c8..09d89a568cd5 100644
--- a/drivers/lightnvm/pblk-core.c
+++ b/drivers/lightnvm/pblk-core.c
@@ -1058,6 +1058,25 @@ static int pblk_line_init_metadata(struct pblk *pblk, struct pblk_line *line,
 	return 1;
 }
 
+static int pblk_line_alloc_bitmaps(struct pblk *pblk, struct pblk_line *line)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+
+	line->map_bitmap = kzalloc(lm->sec_bitmap_len, GFP_KERNEL);
+	if (!line->map_bitmap)
+		return -ENOMEM;
+
+	/* will be initialized using bb info from map_bitmap */
+	line->invalid_bitmap = kmalloc(lm->sec_bitmap_len, GFP_KERNEL);
+	if (!line->invalid_bitmap) {
+		kfree(line->map_bitmap);
+		line->map_bitmap = NULL;
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
 /* For now lines are always assumed full lines. Thus, smeta former and current
  * lun bitmaps are omitted.
  */
@@ -1162,18 +1181,7 @@ static int pblk_line_prepare(struct pblk *pblk, struct pblk_line *line)
 {
 	struct pblk_line_meta *lm = &pblk->lm;
 	int blk_in_line = atomic_read(&line->blk_in_line);
-	int blk_to_erase, ret;
-
-	line->map_bitmap = kzalloc(lm->sec_bitmap_len, GFP_ATOMIC);
-	if (!line->map_bitmap)
-		return -ENOMEM;
-
-	/* will be initialized using bb info from map_bitmap */
-	line->invalid_bitmap = kmalloc(lm->sec_bitmap_len, GFP_ATOMIC);
-	if (!line->invalid_bitmap) {
-		ret = -ENOMEM;
-		goto fail_free_map_bitmap;
-	}
+	int blk_to_erase;
 
 	/* Bad blocks do not need to be erased */
 	bitmap_copy(line->erase_bitmap, line->blk_bitmap, lm->blk_per_line);
@@ -1191,15 +1199,15 @@ static int pblk_line_prepare(struct pblk *pblk, struct pblk_line *line)
 	}
 
 	if (blk_in_line < lm->min_blk_line) {
-		ret = -EAGAIN;
-		goto fail_free_invalid_bitmap;
+		spin_unlock(&line->lock);
+		return -EAGAIN;
 	}
 
 	if (line->state != PBLK_LINESTATE_FREE) {
 		WARN(1, "pblk: corrupted line %d, state %d\n",
 							line->id, line->state);
-		ret = -EINTR;
-		goto fail_free_invalid_bitmap;
+		spin_unlock(&line->lock);
+		return -EINTR;
 	}
 
 	line->state = PBLK_LINESTATE_OPEN;
@@ -1213,16 +1221,6 @@ static int pblk_line_prepare(struct pblk *pblk, struct pblk_line *line)
 	kref_init(&line->ref);
 
 	return 0;
-
-fail_free_invalid_bitmap:
-	spin_unlock(&line->lock);
-	kfree(line->invalid_bitmap);
-	line->invalid_bitmap = NULL;
-fail_free_map_bitmap:
-	kfree(line->map_bitmap);
-	line->map_bitmap = NULL;
-
-	return ret;
 }
 
 int pblk_line_recov_alloc(struct pblk *pblk, struct pblk_line *line)
@@ -1242,13 +1240,16 @@ int pblk_line_recov_alloc(struct pblk *pblk, struct pblk_line *line)
 	}
 	spin_unlock(&l_mg->free_lock);
 
-	pblk_rl_free_lines_dec(&pblk->rl, line, true);
+	ret = pblk_line_alloc_bitmaps(pblk, line);
+	if (ret)
+		return ret;
 
 	if (!pblk_line_init_bb(pblk, line, 0)) {
 		list_add(&line->list, &l_mg->free_list);
 		return -EINTR;
 	}
 
+	pblk_rl_free_lines_dec(&pblk->rl, line, true);
 	return 0;
 }
 
@@ -1260,6 +1261,24 @@ void pblk_line_recov_close(struct pblk *pblk, struct pblk_line *line)
 	line->emeta = NULL;
 }
 
+static void pblk_line_reinit(struct pblk_line *line)
+{
+	*line->vsc = cpu_to_le32(EMPTY_ENTRY);
+
+	line->map_bitmap = NULL;
+	line->invalid_bitmap = NULL;
+	line->smeta = NULL;
+	line->emeta = NULL;
+}
+
+void pblk_line_free(struct pblk_line *line)
+{
+	kfree(line->map_bitmap);
+	kfree(line->invalid_bitmap);
+
+	pblk_line_reinit(line);
+}
+
 struct pblk_line *pblk_line_get(struct pblk *pblk)
 {
 	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
@@ -1326,11 +1345,14 @@ static struct pblk_line *pblk_line_retry(struct pblk *pblk,
 		return NULL;
 	}
 
+	retry_line->map_bitmap = line->map_bitmap;
+	retry_line->invalid_bitmap = line->invalid_bitmap;
 	retry_line->smeta = line->smeta;
 	retry_line->emeta = line->emeta;
 	retry_line->meta_line = line->meta_line;
 
-	pblk_line_free(line);
+	pblk_line_reinit(line);
+
 	l_mg->data_line = retry_line;
 	spin_unlock(&l_mg->free_lock);
 
@@ -1383,6 +1405,9 @@ struct pblk_line *pblk_line_get_first_data(struct pblk *pblk)
 	}
 	spin_unlock(&l_mg->free_lock);
 
+	if (pblk_line_alloc_bitmaps(pblk, line))
+		return NULL;
+
 	if (pblk_line_erase(pblk, line)) {
 		line = pblk_line_retry(pblk, line);
 		if (!line)
@@ -1527,6 +1552,9 @@ struct pblk_line *pblk_line_replace_data(struct pblk *pblk)
 		goto retry_erase;
 	}
 
+	if (pblk_line_alloc_bitmaps(pblk, new))
+		return NULL;
+
 retry_setup:
 	if (!pblk_line_init_metadata(pblk, new, cur)) {
 		new = pblk_line_retry(pblk, new);
@@ -1566,19 +1594,6 @@ struct pblk_line *pblk_line_replace_data(struct pblk *pblk)
 	return new;
 }
 
-void pblk_line_free(struct pblk_line *line)
-{
-	kfree(line->map_bitmap);
-	kfree(line->invalid_bitmap);
-
-	*line->vsc = cpu_to_le32(EMPTY_ENTRY);
-
-	line->map_bitmap = NULL;
-	line->invalid_bitmap = NULL;
-	line->smeta = NULL;
-	line->emeta = NULL;
-}
-
 static void __pblk_line_put(struct pblk *pblk, struct pblk_line *line)
 {
 	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
-- 
2.7.4