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4a09f4a23a
Some variables relative with paravirt feature are declared in the header
file asm/qspinlock.h, however this file can be included only when option
CONFIG_SMP is on. There is compiling warnings if CONFIG_SMP is off since
variables are not declared.
Move these variable declarations to header file asm/paravirt.h to avoid
compiling warnings.
Fixes: c43dce6f13 ("LoongArch: KVM: Make vcpu_is_preempted() as a macro rather than function")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202605061313.O8Hswm2b-lkp@intel.com/
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
61 lines
1.4 KiB
C
61 lines
1.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_LOONGARCH_QSPINLOCK_H
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#define _ASM_LOONGARCH_QSPINLOCK_H
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#include <asm/kvm_para.h>
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#include <asm/paravirt.h>
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#ifdef CONFIG_PARAVIRT
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#define virt_spin_lock virt_spin_lock
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static inline bool virt_spin_lock(struct qspinlock *lock)
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{
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int val;
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if (!static_branch_unlikely(&virt_spin_lock_key))
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return false;
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/*
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* On hypervisors without PARAVIRT_SPINLOCKS support we fall
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* back to a Test-and-Set spinlock, because fair locks have
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* horrible lock 'holder' preemption issues.
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*/
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__retry:
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val = atomic_read(&lock->val);
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if (val || !atomic_try_cmpxchg(&lock->val, &val, _Q_LOCKED_VAL)) {
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cpu_relax();
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goto __retry;
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}
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return true;
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}
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/*
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* Macro is better than inline function here
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* With macro, parameter cpu is parsed only when it is used.
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* With inline function, parameter cpu is parsed even though it is not used.
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* This may cause cache line thrashing across NUMA nodes.
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*/
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#define vcpu_is_preempted(cpu) \
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({ \
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bool __val; \
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\
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if (!static_branch_unlikely(&virt_preempt_key)) \
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__val = false; \
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else { \
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struct kvm_steal_time *src; \
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src = &per_cpu(steal_time, cpu); \
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__val = !!(READ_ONCE(src->preempted) & KVM_VCPU_PREEMPTED); \
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} \
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__val; \
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})
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#endif /* CONFIG_PARAVIRT */
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#include <asm-generic/qspinlock.h>
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#endif // _ASM_LOONGARCH_QSPINLOCK_H
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