linux-kernel - [PATCH v2 1/7] regulator/core: regulator_lock

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Message-Id: <121c27939458ca3c1424b38fd6cee2d81cef831e.1693416477.git.mirq-linux@rere.qmqm.pl>
Date:   Wed, 30 Aug 2023 19:35:30 +0200
From:   Michał Mirosław <mirq-linux@...e.qmqm.pl>
To:     Liam Girdwood <lgirdwood@...il.com>,
        Mark Brown <broonie@...nel.org>
Cc:     linux-kernel@...r.kernel.org,
        Douglas Anderson <dianders@...omium.org>,
        Stephen Boyd <swboyd@...omium.org>
Subject: [PATCH v2 1/7] regulator/core: regulator_lock_nested: remove `lock`

`lock` is only false when the `rdev` is already locked and the owner is
`current`. In this case `ret` is always zero. By removing `lock`, we
thus remove `mutex_owner` write avoidance, but make the code flow more
understandable.

Reviewed-by: Douglas Anderson <dianders@...omium.org>
Signed-off-by: Michał Mirosław <mirq-linux@...e.qmqm.pl>
---
 drivers/regulator/core.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index d8e1caaf207e..215b721e5cd4 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -141,27 +141,19 @@ static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
 static inline int regulator_lock_nested(struct regulator_dev *rdev,
 					struct ww_acquire_ctx *ww_ctx)
 {
-	bool lock = false;
 	int ret = 0;
 
 	mutex_lock(&regulator_nesting_mutex);
 
 	if (!ww_mutex_trylock(&rdev->mutex, ww_ctx)) {
-		if (rdev->mutex_owner == current)
-			rdev->ref_cnt++;
-		else
-			lock = true;
-
-		if (lock) {
+		if (rdev->mutex_owner != current) {
 			mutex_unlock(&regulator_nesting_mutex);
 			ret = ww_mutex_lock(&rdev->mutex, ww_ctx);
 			mutex_lock(&regulator_nesting_mutex);
 		}
-	} else {
-		lock = true;
 	}
 
-	if (lock && ret != -EDEADLK) {
+	if (ret != -EDEADLK) {
 		rdev->ref_cnt++;
 		rdev->mutex_owner = current;
 	}
-- 
2.39.2