From c43dce6f13fb12144571c168c7a593e5e546f3b5 Mon Sep 17 00:00:00 2001 From: Bibo Mao Date: Thu, 9 Apr 2026 18:56:36 +0800 Subject: LoongArch: KVM: Make vcpu_is_preempted() as a macro rather than function vcpu_is_preempted() is performance sensitive that called in function osq_lock(), here make it as a macro. So that parameter is not parsed at most time, it can avoid cache line thrashing across numa nodes. Here is part of UnixBench result on Loongson-3C5000 DualWay machine with 32 cores and 2 numa nodes. original inline macro execl 7025.7 6991.2 7242.3 fstime 474.6 703.1 1071 From the test result, making vcpu_is_preempted() as a macro is the best, and there is some improvment compared with the original function method. Signed-off-by: Bibo Mao Signed-off-by: Huacai Chen --- arch/loongarch/kernel/paravirt.c | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-) (limited to 'arch/loongarch/kernel') diff --git a/arch/loongarch/kernel/paravirt.c b/arch/loongarch/kernel/paravirt.c index b74fe6db49ab..10821cce554c 100644 --- a/arch/loongarch/kernel/paravirt.c +++ b/arch/loongarch/kernel/paravirt.c @@ -10,9 +10,9 @@ #include static int has_steal_clock; -static DEFINE_PER_CPU(struct kvm_steal_time, steal_time) __aligned(64); -static DEFINE_STATIC_KEY_FALSE(virt_preempt_key); +DEFINE_STATIC_KEY_FALSE(virt_preempt_key); DEFINE_STATIC_KEY_FALSE(virt_spin_lock_key); +DEFINE_PER_CPU(struct kvm_steal_time, steal_time) __aligned(64); static bool steal_acc = true; @@ -260,18 +260,6 @@ static int pv_time_cpu_down_prepare(unsigned int cpu) return 0; } - -bool vcpu_is_preempted(int cpu) -{ - struct kvm_steal_time *src; - - if (!static_branch_unlikely(&virt_preempt_key)) - return false; - - src = &per_cpu(steal_time, cpu); - return !!(src->preempted & KVM_VCPU_PREEMPTED); -} -EXPORT_SYMBOL(vcpu_is_preempted); #endif static void pv_cpu_reboot(void *unused) -- cgit v1.2.3