[tip: locking/kcsan] checkpatch: Warn about data_race() without comment

[tip-bot2 for Marco Elver]

The following commit has been merged into the locking/kcsan branch of tip:

Commit-ID:     5099a722e9727fe9a93fac51e961735f40e5b6c8
Gitweb:        https://git.kernel.org/tip/5099a722e9727fe9a93fac51e961735f40e5b6c8
Author:        Marco Elver <elver@xxxxxxxxxx>
AuthorDate:    Wed, 01 Apr 2020 12:17:14 +02:00
Committer:     Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Wed, 06 May 2020 10:54:58 -07:00

checkpatch: Warn about data_race() without comment

Warn about applications of data_race() without a comment, to encourage
documenting the reasoning behind why it was deemed safe.

Suggested-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
 scripts/checkpatch.pl | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index a63380c..48bb950 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5833,6 +5833,14 @@ sub process {
 			}
 		}
 
+# check for data_race without a comment.
+		if ($line =~ /\bdata_race\s*\(/) {
+			if (!ctx_has_comment($first_line, $linenr)) {
+				WARN("DATA_RACE",
+				     "data_race without comment\n" . $herecurr);
+			}
+		}
+
 # check for smp_read_barrier_depends and read_barrier_depends
 		if (!$file && $line =~ /\b(smp_|)read_barrier_depends\s*\(/) {
 			WARN("READ_BARRIER_DEPENDS",