From: Wen Yang <wen.yang@linux.dev>
To: Bjorn Andersson <andersson@kernel.org>,
Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Wen Yang <wen.yang@linux.dev>, Dave Young <dyoung@redhat.com>,
linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] hwspinlock: improve locking safety by using raw_spinlock_t
Date: Sat, 24 Aug 2024 22:38:47 +0800 [thread overview]
Message-ID: <20240824143847.5307-1-wen.yang@linux.dev> (raw)
Both __hwspin_trylock and __hwspin_unlock use hwlock->lock, and require
running in atomic context, with a special annotation:
function will never sleep.
However, this requirement is not fulfilled on PREEMPT_RT.
To address it, use raw_spinlock_t instead of spin_lock_t.
Signed-off-by: Wen Yang <wen.yang@linux.dev>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: linux-remoteproc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
drivers/hwspinlock/hwspinlock_core.c | 20 ++++++++++----------
drivers/hwspinlock/hwspinlock_internal.h | 2 +-
2 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c
index 6505261e6068..76e5a6c645b1 100644
--- a/drivers/hwspinlock/hwspinlock_core.c
+++ b/drivers/hwspinlock/hwspinlock_core.c
@@ -111,17 +111,17 @@ int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
*/
switch (mode) {
case HWLOCK_IRQSTATE:
- ret = spin_trylock_irqsave(&hwlock->lock, *flags);
+ ret = raw_spin_trylock_irqsave(&hwlock->lock, *flags);
break;
case HWLOCK_IRQ:
- ret = spin_trylock_irq(&hwlock->lock);
+ ret = raw_spin_trylock_irq(&hwlock->lock);
break;
case HWLOCK_RAW:
case HWLOCK_IN_ATOMIC:
ret = 1;
break;
default:
- ret = spin_trylock(&hwlock->lock);
+ ret = raw_spin_trylock(&hwlock->lock);
break;
}
@@ -136,17 +136,17 @@ int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
if (!ret) {
switch (mode) {
case HWLOCK_IRQSTATE:
- spin_unlock_irqrestore(&hwlock->lock, *flags);
+ raw_spin_unlock_irqrestore(&hwlock->lock, *flags);
break;
case HWLOCK_IRQ:
- spin_unlock_irq(&hwlock->lock);
+ raw_spin_unlock_irq(&hwlock->lock);
break;
case HWLOCK_RAW:
case HWLOCK_IN_ATOMIC:
/* Nothing to do */
break;
default:
- spin_unlock(&hwlock->lock);
+ raw_spin_unlock(&hwlock->lock);
break;
}
@@ -289,17 +289,17 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
/* Undo the spin_trylock{_irq, _irqsave} called while locking */
switch (mode) {
case HWLOCK_IRQSTATE:
- spin_unlock_irqrestore(&hwlock->lock, *flags);
+ raw_spin_unlock_irqrestore(&hwlock->lock, *flags);
break;
case HWLOCK_IRQ:
- spin_unlock_irq(&hwlock->lock);
+ raw_spin_unlock_irq(&hwlock->lock);
break;
case HWLOCK_RAW:
case HWLOCK_IN_ATOMIC:
/* Nothing to do */
break;
default:
- spin_unlock(&hwlock->lock);
+ raw_spin_unlock(&hwlock->lock);
break;
}
}
@@ -535,7 +535,7 @@ int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
for (i = 0; i < num_locks; i++) {
hwlock = &bank->lock[i];
- spin_lock_init(&hwlock->lock);
+ raw_spin_lock_init(&hwlock->lock);
hwlock->bank = bank;
ret = hwspin_lock_register_single(hwlock, base_id + i);
diff --git a/drivers/hwspinlock/hwspinlock_internal.h b/drivers/hwspinlock/hwspinlock_internal.h
index f298fc0ee5ad..9fbd66e8a82f 100644
--- a/drivers/hwspinlock/hwspinlock_internal.h
+++ b/drivers/hwspinlock/hwspinlock_internal.h
@@ -42,7 +42,7 @@ struct hwspinlock_ops {
*/
struct hwspinlock {
struct hwspinlock_device *bank;
- spinlock_t lock;
+ raw_spinlock_t lock;
void *priv;
};
--
2.25.1
next reply other threads:[~2024-08-24 14:39 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-08-24 14:38 Wen Yang [this message]
2024-08-26 16:37 ` [PATCH] hwspinlock: improve locking safety by using raw_spinlock_t Bjorn Andersson
2024-09-01 13:34 ` Wen Yang
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