Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
Cc:     tytso@mit.edu, jack@suse.com, linux-ext4@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Alexander Lochmann <alexander.lochmann@tu-dortmund.de>,
        Horst Schirmeier <horst.schirmeier@tu-dortmund.de>
Subject: [PATCH 1/1] Updated locking documentation for struct journal_t
Date:   Fri,  8 Mar 2019 16:06:05 +0100
Message-Id: <20190308150605.98405-1-alexander.lochmann@tu-dortmund.de>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
To:     unlisted-recipients:; (no To-header on input)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

We used LockDoc to derive locking rules for each member
of struct journal_t. Based on those results, we extended
the existing documentation by more members
of struct inode, and updated the existing documentation.

Signed-off-by: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
Signed-off-by: Horst Schirmeier <horst.schirmeier@tu-dortmund.de>
---
 include/linux/jbd2.h | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 0f919d5fe84f..c1ba44ca515a 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -585,7 +585,8 @@ struct transaction_s
 	}			t_state;
 
 	/*
-	 * Where in the log does this transaction's commit start? [no locking]
+	 * Where in the log does this transaction's commit start?
+	 * [journal_t->j_state_lock]
 	 */
 	unsigned long		t_log_start;
 
@@ -647,17 +648,17 @@ struct transaction_s
 	unsigned long		t_max_wait;
 
 	/*
-	 * When transaction started
+	 * When transaction started [j_state_lock]
 	 */
 	unsigned long		t_start;
 
 	/*
-	 * When commit was requested
+	 * When commit was requested [j_state_lock]
 	 */
 	unsigned long		t_requested;
 
 	/*
-	 * Checkpointing stats [j_checkpoint_sem]
+	 * Checkpointing stats [j_list_lock]
 	 */
 	struct transaction_chp_stats_s t_chp_stats;
 
@@ -744,6 +745,7 @@ jbd2_time_diff(unsigned long start, unsigned long end)
 /**
  * struct journal_s - The journal_s type is the concrete type associated with
  *     journal_t.
+ * (Locking Documentation improved by LockDoc)
  */
 struct journal_s
 {
@@ -762,6 +764,7 @@ struct journal_s
 
 	/**
 	 * @j_sb_buffer: The first part of the superblock buffer.
+	 * [j_checkpoint_mutex]
 	 */
 	struct buffer_head	*j_sb_buffer;
 
@@ -1015,6 +1018,7 @@ struct journal_s
 	 * @j_commit_interval:
 	 *
 	 * What is the maximum transaction lifetime before we begin a commit?
+	 * [super_block->s_umount]
 	 */
 	unsigned long		j_commit_interval;
 
@@ -1032,7 +1036,7 @@ struct journal_s
 	 * @j_revoke:
 	 *
 	 * The revoke table - maintains the list of revoked blocks in the
-	 * current transaction.
+	 * current transaction. [j_state_lock]
 	 */
 	struct jbd2_revoke_table_s *j_revoke;
 
-- 
2.20.1