[prev in list] [next in list] [prev in thread] [next in thread] 

List:       alsa-devel
Subject:    [PATCH 1/6] ALSA: emu10k1: remove pointless locks from timer code
From:       Oswald Buddenhagen <oswald.buddenhagen () gmx ! de>
Date:       2023-04-28 9:59:36
Message-ID: 20230428095941.1706278-2-oswald.buddenhagen () gmx ! de
[Download RAW message or body]

Contrary to its name, reg_lock locks the emu data structure, not the
registers. As the functions access only data which is set once at card
initialization, there is no point in locking it.

Actually locking the registers would be pointless as well, as
snd_emu10k1_intr_{en,dis}able() does its own locking, and TIMER is
accessed only in this one place.

Locking snd_emu10k1_timer_{start,stop}() against each other also
wouldn't buy us anything; the functions interleaving their I/O accesses
wouldn't introduce new problems.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
---
 sound/pci/emu10k1/timer.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/sound/pci/emu10k1/timer.c b/sound/pci/emu10k1/timer.c
index 2435d3ba68f7..993663fef885 100644
--- a/sound/pci/emu10k1/timer.c
+++ b/sound/pci/emu10k1/timer.c
@@ -18,29 +18,23 @@
 static int snd_emu10k1_timer_start(struct snd_timer *timer)
 {
 	struct snd_emu10k1 *emu;
-	unsigned long flags;
 	unsigned int delay;
 
 	emu = snd_timer_chip(timer);
 	delay = timer->sticks - 1;
 	if (delay < 5 ) /* minimum time is 5 ticks */
 		delay = 5;
-	spin_lock_irqsave(&emu->reg_lock, flags);
 	snd_emu10k1_intr_enable(emu, INTE_INTERVALTIMERENB);
 	outw(delay & TIMER_RATE_MASK, emu->port + TIMER);
-	spin_unlock_irqrestore(&emu->reg_lock, flags);
 	return 0;
 }
 
 static int snd_emu10k1_timer_stop(struct snd_timer *timer)
 {
 	struct snd_emu10k1 *emu;
-	unsigned long flags;
 
 	emu = snd_timer_chip(timer);
-	spin_lock_irqsave(&emu->reg_lock, flags);
 	snd_emu10k1_intr_disable(emu, INTE_INTERVALTIMERENB);
-	spin_unlock_irqrestore(&emu->reg_lock, flags);
 	return 0;
 }
 
-- 
2.40.0.152.g15d061e6df

[prev in list] [next in list] [prev in thread] [next in thread]