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kernel
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linux
parisc: Improve interrupt handling in arch_spin_lock_flags()
Rewrite arch_spin_lock() and arch_spin_lock_flags() to not re-enable and
disable the PSW_SM_I interrupt flag too often.
Signed-off-by: Helge Deller <deller@gmx.de>
+19
-10
+19
-10
arch/parisc/include/asm/spinlock.h
+19
-10
arch/parisc/include/asm/spinlock.h
···
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static inline int arch_spin_is_locked(arch_spinlock_t *x)
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{
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volatile unsigned int *a = __ldcw_align(x);
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+
smp_mb();
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return *a == 0;
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}
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-
#define arch_spin_lock(lock) arch_spin_lock_flags(lock, 0)
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-
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-
static inline void arch_spin_lock_flags(arch_spinlock_t *x,
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-
unsigned long flags)
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+
static inline void arch_spin_lock(arch_spinlock_t *x)
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{
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volatile unsigned int *a;
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a = __ldcw_align(x);
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while (__ldcw(a) == 0)
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while (*a == 0)
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-
if (flags & PSW_SM_I) {
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-
local_irq_enable();
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-
cpu_relax();
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local_irq_disable();
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-
} else
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-
cpu_relax();
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cpu_relax();
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}
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+
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static inline void arch_spin_lock_flags(arch_spinlock_t *x,
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+
unsigned long flags)
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+
{
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volatile unsigned int *a;
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unsigned long flags_dis;
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+
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a = __ldcw_align(x);
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+
while (__ldcw(a) == 0) {
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local_save_flags(flags_dis);
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local_irq_restore(flags);
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while (*a == 0)
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cpu_relax();
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local_irq_restore(flags_dis);
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}
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}
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#define arch_spin_lock_flags arch_spin_lock_flags
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