d8d0da4eee
include/asm-generic/qrwlock.h was trying to get arch_spin_is_locked via
asm-generic/qspinlock.h. However, this does not work because architectures
might be using queued rwlocks but not queued spinlocks (csky), or because they
might be defining their own queued_* macros before including asm/qspinlock.h.
To fix this, ensure that asm/spinlock.h always includes qrwlock.h after
defining arch_spin_is_locked (either directly for csky, or via
asm/qspinlock.h for other architectures). The only inclusion elsewhere
is in kernel/locking/qrwlock.c. That one is really unnecessary because
the file is only compiled in SMP configurations (config QUEUED_RWLOCKS
depends on SMP) and in that case linux/spinlock.h already includes
asm/qrwlock.h if needed, via asm/spinlock.h.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Waiman Long <longman@redhat.com>
Fixes: 26128cb6c7e6 ("locking/rwlocks: Add contention detection for rwlocks")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Ben Gardon <bgardon@google.com>
[Add arch/sparc and kernel/locking parts per discussion with Waiman. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
28 lines
601 B
C
28 lines
601 B
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (C) 2012 ARM Ltd.
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*/
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#ifndef __ASM_SPINLOCK_H
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#define __ASM_SPINLOCK_H
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#include <asm/qspinlock.h>
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#include <asm/qrwlock.h>
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/* See include/linux/spinlock.h */
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#define smp_mb__after_spinlock() smp_mb()
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/*
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* Changing this will break osq_lock() thanks to the call inside
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* smp_cond_load_relaxed().
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*
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* See:
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* https://lore.kernel.org/lkml/20200110100612.GC2827@hirez.programming.kicks-ass.net
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*/
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#define vcpu_is_preempted vcpu_is_preempted
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static inline bool vcpu_is_preempted(int cpu)
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{
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return false;
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}
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#endif /* __ASM_SPINLOCK_H */
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