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author | Paul Mackerras | 2011-12-15 03:02:47 +0100 |
---|---|---|
committer | Avi Kivity | 2012-03-05 13:52:39 +0100 |
commit | 55514893739d28f095f19b012133eea4cb4a9390 (patch) | |
tree | 53133098473395a8a4ff1f00414137c2481a5fd0 /arch/powerpc/kvm/book3s_64_mmu_hv.c | |
parent | KVM: PPC: Book3s HV: Maintain separate guest and host views of R and C bits (diff) | |
download | kernel-qcow2-linux-55514893739d28f095f19b012133eea4cb4a9390.tar.gz kernel-qcow2-linux-55514893739d28f095f19b012133eea4cb4a9390.tar.xz kernel-qcow2-linux-55514893739d28f095f19b012133eea4cb4a9390.zip |
KVM: PPC: Book3S HV: Use the hardware referenced bit for kvm_age_hva
This uses the host view of the hardware R (referenced) bit to speed
up kvm_age_hva() and kvm_test_age_hva(). Instead of removing all
the relevant HPTEs in kvm_age_hva(), we now just reset their R bits
if set. Also, kvm_test_age_hva() now scans the relevant HPTEs to
see if any of them have R set.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_hv.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_hv.c | 81 |
1 files changed, 70 insertions, 11 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index aa51ddef468e..926e2b92bdab 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -772,16 +772,50 @@ int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn) { - if (!kvm->arch.using_mmu_notifiers) - return 0; - if (!(*rmapp & KVMPPC_RMAP_REFERENCED)) - return 0; - kvm_unmap_rmapp(kvm, rmapp, gfn); - while (test_and_set_bit_lock(KVMPPC_RMAP_LOCK_BIT, rmapp)) - cpu_relax(); - *rmapp &= ~KVMPPC_RMAP_REFERENCED; - __clear_bit_unlock(KVMPPC_RMAP_LOCK_BIT, rmapp); - return 1; + struct revmap_entry *rev = kvm->arch.revmap; + unsigned long head, i, j; + unsigned long *hptep; + int ret = 0; + + retry: + lock_rmap(rmapp); + if (*rmapp & KVMPPC_RMAP_REFERENCED) { + *rmapp &= ~KVMPPC_RMAP_REFERENCED; + ret = 1; + } + if (!(*rmapp & KVMPPC_RMAP_PRESENT)) { + unlock_rmap(rmapp); + return ret; + } + + i = head = *rmapp & KVMPPC_RMAP_INDEX; + do { + hptep = (unsigned long *) (kvm->arch.hpt_virt + (i << 4)); + j = rev[i].forw; + + /* If this HPTE isn't referenced, ignore it */ + if (!(hptep[1] & HPTE_R_R)) + continue; + + if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) { + /* unlock rmap before spinning on the HPTE lock */ + unlock_rmap(rmapp); + while (hptep[0] & HPTE_V_HVLOCK) + cpu_relax(); + goto retry; + } + + /* Now check and modify the HPTE */ + if ((hptep[0] & HPTE_V_VALID) && (hptep[1] & HPTE_R_R)) { + kvmppc_clear_ref_hpte(kvm, hptep, i); + rev[i].guest_rpte |= HPTE_R_R; + ret = 1; + } + hptep[0] &= ~HPTE_V_HVLOCK; + } while ((i = j) != head); + + unlock_rmap(rmapp); + return ret; } int kvm_age_hva(struct kvm *kvm, unsigned long hva) @@ -794,7 +828,32 @@ int kvm_age_hva(struct kvm *kvm, unsigned long hva) static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn) { - return !!(*rmapp & KVMPPC_RMAP_REFERENCED); + struct revmap_entry *rev = kvm->arch.revmap; + unsigned long head, i, j; + unsigned long *hp; + int ret = 1; + + if (*rmapp & KVMPPC_RMAP_REFERENCED) + return 1; + + lock_rmap(rmapp); + if (*rmapp & KVMPPC_RMAP_REFERENCED) + goto out; + + if (*rmapp & KVMPPC_RMAP_PRESENT) { + i = head = *rmapp & KVMPPC_RMAP_INDEX; + do { + hp = (unsigned long *)(kvm->arch.hpt_virt + (i << 4)); + j = rev[i].forw; + if (hp[1] & HPTE_R_R) + goto out; + } while ((i = j) != head); + } + ret = 0; + + out: + unlock_rmap(rmapp); + return ret; } int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) |