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| author |   Oliver Upton <oliver.upton@linux.dev> | 2024-02-21 05:42:49 +0000 |
|---|---|---|
| committer | Oliver Upton <oliver.upton@linux.dev> | 2024-02-23 21:46:02 +0000 |
| commit | 05f4d4f5d462618150a199bf26fd442b54b5d41a (patch) | |
| tree | dbe257e3dd1c896eed33649aea1101b46cf42abf | |
| parent | KVM: arm64: vgic: Get rid of the LPI linked-list (diff) | |
| download | wireguard-linux-05f4d4f5d462618150a199bf26fd442b54b5d41a.tar.xz wireguard-linux-05f4d4f5d462618150a199bf26fd442b54b5d41a.zip | |
KVM: arm64: vgic: Use atomics to count LPIs
Switch to using atomics for LPI accounting, allowing vgic_irq references
to be dropped in parallel.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240221054253.3848076-7-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-debug.c | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-its.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic.c | 2 | ||||
| -rw-r--r-- | include/kvm/arm_vgic.h | 4 |
4 files changed, 6 insertions, 6 deletions
diff --git a/arch/arm64/kvm/vgic/vgic-debug.c b/arch/arm64/kvm/vgic/vgic-debug.c index 85606a531dc3..389025ce7749 100644 --- a/arch/arm64/kvm/vgic/vgic-debug.c +++ b/arch/arm64/kvm/vgic/vgic-debug.c @@ -149,7 +149,7 @@ static void print_dist_state(struct seq_file *s, struct vgic_dist *dist) seq_printf(s, "vgic_model:\t%s\n", v3 ? "GICv3" : "GICv2"); seq_printf(s, "nr_spis:\t%d\n", dist->nr_spis); if (v3) - seq_printf(s, "nr_lpis:\t%d\n", dist->lpi_list_count); + seq_printf(s, "nr_lpis:\t%d\n", atomic_read(&dist->lpi_count)); seq_printf(s, "enabled:\t%d\n", dist->enabled); seq_printf(s, "\n"); diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 3d0208162bcd..0be3c33676c3 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -96,7 +96,7 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid, goto out_unlock; } - dist->lpi_list_count++; + atomic_inc(&dist->lpi_count); out_unlock: raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags); @@ -346,7 +346,7 @@ int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr) * command). If coming from another path (such as enabling LPIs), * we must be careful not to overrun the array. */ - irq_count = READ_ONCE(dist->lpi_list_count); + irq_count = atomic_read(&dist->lpi_count); intids = kmalloc_array(irq_count, sizeof(intids[0]), GFP_KERNEL_ACCOUNT); if (!intids) return -ENOMEM; diff --git a/arch/arm64/kvm/vgic/vgic.c b/arch/arm64/kvm/vgic/vgic.c index 6240faab0127..15dbd17b3a9e 100644 --- a/arch/arm64/kvm/vgic/vgic.c +++ b/arch/arm64/kvm/vgic/vgic.c @@ -123,7 +123,7 @@ void __vgic_put_lpi_locked(struct kvm *kvm, struct vgic_irq *irq) return; xa_erase(&dist->lpi_xa, irq->intid); - dist->lpi_list_count--; + atomic_dec(&dist->lpi_count); kfree(irq); } diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index aeff363e3ba6..71e9d719533b 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -273,10 +273,10 @@ struct vgic_dist { */ u64 propbaser; - /* Protects the lpi_list and the count value below. */ + /* Protects the lpi_list. */ raw_spinlock_t lpi_list_lock; struct xarray lpi_xa; - int lpi_list_count; + atomic_t lpi_count; /* LPI translation cache */ struct list_head lpi_translation_cache; |