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From:   "=?UTF-8?q?Javier=20Gonz=C3=A1lez?=" <javier@javigon.com>
To:     mb@lightnvm.io
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        =?UTF-8?q?Javier=20Gonz=C3=A1lez?= <javier@cnexlabs.com>
Subject: [PATCH] lightnvm: pblk: add comments wrt locking in recovery path
Date:   Wed, 28 Nov 2018 12:20:16 +0100
Message-Id: <1543404016-14902-1-git-send-email-javier@cnexlabs.com>
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Sender: linux-kernel-owner@vger.kernel.org
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pblk's recovery path is single threaded and therefore a number of
assumptions regarding concurrency can be made. To avoid confusion, make
this explicit with a couple of comments in the code.

Signed-off-by: Javier González <javier@cnexlabs.com>
---
 drivers/lightnvm/pblk-core.c     | 1 +
 drivers/lightnvm/pblk-recovery.c | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
index 44c5dc046912..f1b411e7c7c9 100644
--- a/drivers/lightnvm/pblk-core.c
+++ b/drivers/lightnvm/pblk-core.c
@@ -1276,6 +1276,7 @@ static int pblk_line_prepare(struct pblk *pblk, struct pblk_line *line)
 	return 0;
 }
 
+/* Line allocations in the recovery path are always single threaded */
 int pblk_line_recov_alloc(struct pblk *pblk, struct pblk_line *line)
 {
 	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
diff --git a/drivers/lightnvm/pblk-recovery.c b/drivers/lightnvm/pblk-recovery.c
index 416d9840544b..4c726506a831 100644
--- a/drivers/lightnvm/pblk-recovery.c
+++ b/drivers/lightnvm/pblk-recovery.c
@@ -13,6 +13,9 @@
  * General Public License for more details.
  *
  * pblk-recovery.c - pblk's recovery path
+ *
+ * The L2P recovery path is single threaded as the L2P table is updated in order
+ * following the line sequence ID.
  */
 
 #include "pblk.h"
-- 
2.7.4