linux-kernel - [PATCH 11/15] regulator: core: Use fsleep() to get best sleep mechanism

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240904-devel-anna-maria-b4-timers-flseep-v1-11-e98760256370@linutronix.de>
Date: Wed, 04 Sep 2024 15:05:01 +0200
From: Anna-Maria Behnsen <anna-maria@...utronix.de>
To: Frederic Weisbecker <frederic@...nel.org>, 
 Thomas Gleixner <tglx@...utronix.de>, Jonathan Corbet <corbet@....net>
Cc: linux-kernel@...r.kernel.org, Len Brown <len.brown@...el.com>, 
 "Rafael J. Wysocki" <rafael@...nel.org>, 
 Anna-Maria Behnsen <anna-maria@...utronix.de>, 
 Liam Girdwood <lgirdwood@...il.com>, Mark Brown <broonie@...nel.org>
Subject: [PATCH 11/15] regulator: core: Use fsleep() to get best sleep
 mechanism

_regulator_delay_helper() implements the recommondation of the outdated
documentation which sleep mechanism should be used. There is already a
function in place which does everything and also maps to reality called
fsleep().

Use fsleep() to choose the best mechanism.

Cc: Liam Girdwood <lgirdwood@...il.com>
Cc: Mark Brown <broonie@...nel.org>
Signed-off-by: Anna-Maria Behnsen <anna-maria@...utronix.de>
---
 drivers/regulator/core.c | 33 ++++-----------------------------
 1 file changed, 4 insertions(+), 29 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 7674b7f2df14..155c3e3ab3f1 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2671,39 +2671,14 @@ static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
  * _regulator_delay_helper - a delay helper function
  * @delay: time to delay in microseconds
  *
- * Delay for the requested amount of time as per the guidelines in:
+ * For details please refere to fsleep() function description.
  *
- *     Documentation/timers/timers-howto.rst
- *
- * The assumption here is that these regulator operations will never used in
+ * The assumption here is that these regulator operations are never used in
  * atomic context and therefore sleeping functions can be used.
  */
-static void _regulator_delay_helper(unsigned int delay)
+static inline void _regulator_delay_helper(unsigned int delay)
 {
-	unsigned int ms = delay / 1000;
-	unsigned int us = delay % 1000;
-
-	if (ms > 0) {
-		/*
-		 * For small enough values, handle super-millisecond
-		 * delays in the usleep_range() call below.
-		 */
-		if (ms < 20)
-			us += ms * 1000;
-		else
-			msleep(ms);
-	}
-
-	/*
-	 * Give the scheduler some room to coalesce with any other
-	 * wakeup sources. For delays shorter than 10 us, don't even
-	 * bother setting up high-resolution timers and just busy-
-	 * loop.
-	 */
-	if (us >= 10)
-		usleep_range(us, us + 100);
-	else
-		udelay(us);
+	fsleep(delay);
 }

 /**

-- 
2.39.2