diff options
author | Julien Grall <julien.grall@arm.com> | 2021-11-22 12:18:43 +0000 |
---|---|---|
committer | Marc Zyngier <maz@kernel.org> | 2022-02-08 14:57:03 +0000 |
commit | 3248136b3637e1671e4fa46e32e2122f9ec4bc3d (patch) | |
tree | f73f39b63f7e6ecf9800b7a796cc5a0b0b186949 /arch/arm64/include | |
parent | f8051e960922a9de8e42159103d5d9c697ef17ec (diff) | |
download | linux-3248136b3637e1671e4fa46e32e2122f9ec4bc3d.tar.bz2 |
KVM: arm64: Align the VMID allocation with the arm64 ASID
At the moment, the VMID algorithm will send an SGI to all the
CPUs to force an exit and then broadcast a full TLB flush and
I-Cache invalidation.
This patch uses the new VMID allocator. The benefits are:
- Aligns with arm64 ASID algorithm.
- CPUs are not forced to exit at roll-over. Instead,
the VMID will be marked reserved and context invalidation
is broadcasted. This will reduce the IPIs traffic.
- More flexible to add support for pinned KVM VMIDs in
the future.
With the new algo, the code is now adapted:
- The call to update_vmid() will be done with preemption
disabled as the new algo requires to store information
per-CPU.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211122121844.867-4-shameerali.kolothum.thodi@huawei.com
Diffstat (limited to 'arch/arm64/include')
-rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 4 | ||||
-rw-r--r-- | arch/arm64/include/asm/kvm_mmu.h | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 1fea13a0857e..47aeed22e2ad 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -71,9 +71,7 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu); void kvm_arm_vcpu_destroy(struct kvm_vcpu *vcpu); struct kvm_vmid { - /* The VMID generation used for the virt. memory system */ - u64 vmid_gen; - u32 vmid; + atomic64_t id; }; struct kvm_s2_mmu { diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 81839e9a8a24..74735a864eee 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -115,6 +115,7 @@ alternative_cb_end #include <asm/cache.h> #include <asm/cacheflush.h> #include <asm/mmu_context.h> +#include <asm/kvm_host.h> void kvm_update_va_mask(struct alt_instr *alt, __le32 *origptr, __le32 *updptr, int nr_inst); @@ -266,7 +267,8 @@ static __always_inline u64 kvm_get_vttbr(struct kvm_s2_mmu *mmu) u64 cnp = system_supports_cnp() ? VTTBR_CNP_BIT : 0; baddr = mmu->pgd_phys; - vmid_field = (u64)READ_ONCE(vmid->vmid) << VTTBR_VMID_SHIFT; + vmid_field = atomic64_read(&vmid->id) << VTTBR_VMID_SHIFT; + vmid_field &= VTTBR_VMID_MASK(kvm_arm_vmid_bits); return kvm_phys_to_vttbr(baddr) | vmid_field | cnp; } |