| Message ID | 5110C87F.7020601@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Feb 05, 2013 at 04:53:19PM +0800, Xiao Guangrong wrote: > There is little different between walking parent pte and walking ramp: > all spte in rmap must be present but this is not true on parent pte list, > in kvm_mmu_alloc_page, we always link the parent list before set the spte > to present > > This patch introduce mmu_spte_establish which set the spte before linking > it to parent list to eliminates the different then it is possible to unify > the code of walking pte list > > Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> > --- > arch/x86/kvm/mmu.c | 81 ++++++++++++++++++++++--------------------- > arch/x86/kvm/paging_tmpl.h | 16 ++++----- > 2 files changed, 48 insertions(+), 49 deletions(-) > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index 8041454..68d4d5f 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -1482,9 +1482,6 @@ static unsigned kvm_page_table_hashfn(gfn_t gfn) > static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu, > struct kvm_mmu_page *sp, u64 *parent_pte) > { > - if (!parent_pte) > - return; > - > pte_list_add(vcpu, parent_pte, &sp->parent_ptes); > } > > @@ -1502,7 +1499,7 @@ static void drop_parent_pte(struct kvm_mmu_page *sp, > } > > static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, > - u64 *parent_pte, int direct) > + int direct) > { > struct kvm_mmu_page *sp; > sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache); > @@ -1512,7 +1509,6 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, > set_page_private(virt_to_page(sp->spt), (unsigned long)sp); > list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); > sp->parent_ptes = 0; > - mmu_page_add_parent_pte(vcpu, sp, parent_pte); > kvm_mod_used_mmu_pages(vcpu->kvm, +1); > return sp; > } > @@ -1845,8 +1841,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, > gva_t gaddr, > unsigned level, > int direct, > - unsigned access, > - u64 *parent_pte) > + unsigned access) > { > union kvm_mmu_page_role role; > unsigned quadrant; > @@ -1876,19 +1871,15 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, > if (sp->unsync && kvm_sync_page_transient(vcpu, sp)) > break; > > - mmu_page_add_parent_pte(vcpu, sp, parent_pte); > - if (sp->unsync_children) { > + if (sp->unsync_children) > kvm_make_request(KVM_REQ_MMU_SYNC, vcpu); > - kvm_mmu_mark_parents_unsync(sp); > - } else if (sp->unsync) > - kvm_mmu_mark_parents_unsync(sp); > > __clear_sp_write_flooding_count(sp); > trace_kvm_mmu_get_page(sp, false); > return sp; > } > ++vcpu->kvm->stat.mmu_cache_miss; > - sp = kvm_mmu_alloc_page(vcpu, parent_pte, direct); > + sp = kvm_mmu_alloc_page(vcpu, direct); > if (!sp) > return sp; > sp->gfn = gfn; > @@ -1908,6 +1899,35 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, > return sp; > } > > +static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp) > +{ > + u64 spte; > + > + spte = __pa(sp->spt) | PT_PRESENT_MASK | PT_WRITABLE_MASK | > + shadow_user_mask | shadow_x_mask | shadow_accessed_mask; > + > + mmu_spte_set(sptep, spte); > +} > + > +static struct kvm_mmu_page * > +mmu_spte_establish(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn, gva_t gaddr, > + unsigned level, int direct, unsigned access) > +{ > + struct kvm_mmu_page *sp; > + > + WARN_ON(is_shadow_present_pte(*spte)); > + > + sp = kvm_mmu_get_page(vcpu, gfn, gaddr, level, direct, access); > + > + link_shadow_page(spte, sp); > + mmu_page_add_parent_pte(vcpu, sp, spte); > + > + if (sp->unsync_children || sp->unsync) > + kvm_mmu_mark_parents_unsync(sp); > + > + return sp; > +} > + > static void shadow_walk_init(struct kvm_shadow_walk_iterator *iterator, > struct kvm_vcpu *vcpu, u64 addr) > { > @@ -1957,16 +1977,6 @@ static void shadow_walk_next(struct kvm_shadow_walk_iterator *iterator) > return __shadow_walk_next(iterator, *iterator->sptep); > } > > -static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp) > -{ > - u64 spte; > - > - spte = __pa(sp->spt) | PT_PRESENT_MASK | PT_WRITABLE_MASK | > - shadow_user_mask | shadow_x_mask | shadow_accessed_mask; > - > - mmu_spte_set(sptep, spte); > -} > - > static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, > unsigned direct_access) > { > @@ -2023,11 +2033,6 @@ static void kvm_mmu_page_unlink_children(struct kvm *kvm, > mmu_page_zap_pte(kvm, sp, sp->spt + i); > } > > -static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte) > -{ > - mmu_page_remove_parent_pte(sp, parent_pte); > -} > - > static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp) > { > u64 *sptep; > @@ -2582,9 +2587,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, > bool prefault) > { > struct kvm_shadow_walk_iterator iterator; > - struct kvm_mmu_page *sp; > int emulate = 0; > - gfn_t pseudo_gfn; > > for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) { > if (iterator.level == level) { > @@ -2602,12 +2605,11 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, > u64 base_addr = iterator.addr; > > base_addr &= PT64_LVL_ADDR_MASK(iterator.level); > - pseudo_gfn = base_addr >> PAGE_SHIFT; > - sp = kvm_mmu_get_page(vcpu, pseudo_gfn, iterator.addr, > - iterator.level - 1, > - 1, ACC_ALL, iterator.sptep); > + mmu_spte_establish(vcpu, iterator.sptep, > + gpa_to_gfn(base_addr), > + iterator.addr, iterator.level - 1, > + 1, ACC_ALL); > > - link_shadow_page(iterator.sptep, sp); > } > } > return emulate; > @@ -2926,7 +2928,7 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) > spin_lock(&vcpu->kvm->mmu_lock); > kvm_mmu_free_some_pages(vcpu); > sp = kvm_mmu_get_page(vcpu, 0, 0, PT64_ROOT_LEVEL, > - 1, ACC_ALL, NULL); > + 1, ACC_ALL); > ++sp->root_count; > spin_unlock(&vcpu->kvm->mmu_lock); > vcpu->arch.mmu.root_hpa = __pa(sp->spt); > @@ -2939,8 +2941,7 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) > kvm_mmu_free_some_pages(vcpu); > sp = kvm_mmu_get_page(vcpu, i << (30 - PAGE_SHIFT), > i << 30, > - PT32_ROOT_LEVEL, 1, ACC_ALL, > - NULL); > + PT32_ROOT_LEVEL, 1, ACC_ALL); > root = __pa(sp->spt); > ++sp->root_count; > spin_unlock(&vcpu->kvm->mmu_lock); > @@ -2977,7 +2978,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) > spin_lock(&vcpu->kvm->mmu_lock); > kvm_mmu_free_some_pages(vcpu); > sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, > - 0, ACC_ALL, NULL); > + 0, ACC_ALL); > root = __pa(sp->spt); > ++sp->root_count; > spin_unlock(&vcpu->kvm->mmu_lock); > @@ -3012,7 +3013,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) > kvm_mmu_free_some_pages(vcpu); > sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, > PT32_ROOT_LEVEL, 0, > - ACC_ALL, NULL); > + ACC_ALL); > root = __pa(sp->spt); > ++sp->root_count; > spin_unlock(&vcpu->kvm->mmu_lock); > diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h > index 105dd5b..3605ff7 100644 > --- a/arch/x86/kvm/paging_tmpl.h > +++ b/arch/x86/kvm/paging_tmpl.h > @@ -434,8 +434,9 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, > sp = NULL; > if (!is_shadow_present_pte(*it.sptep)) { > table_gfn = gw->table_gfn[it.level - 2]; > - sp = kvm_mmu_get_page(vcpu, table_gfn, addr, it.level-1, > - false, access, it.sptep); > + sp = mmu_spte_establish(vcpu, it.sptep, table_gfn, > + addr, it.level-1, false, > + access); > } > > /* > @@ -444,9 +445,6 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, > */ > if (FNAME(gpte_changed)(vcpu, gw, it.level - 1)) > goto out_gpte_changed; > - > - if (sp) > - link_shadow_page(it.sptep, sp); > } > > for (; > @@ -464,9 +462,8 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, > > direct_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1); > > - sp = kvm_mmu_get_page(vcpu, direct_gfn, addr, it.level-1, > - true, direct_access, it.sptep); > - link_shadow_page(it.sptep, sp); > + mmu_spte_establish(vcpu, it.sptep, direct_gfn, addr, + it.level-1, true, direct_access); > } > > clear_sp_write_flooding_count(it.sptep); > @@ -478,7 +475,8 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, > > out_gpte_changed: > if (sp) > - kvm_mmu_put_page(sp, it.sptep); > + drop_parent_pte(sp, it.sptep); > + Unclear why TLB flushing not necessary here (entry it could have been added to remote CPU's TLB since it has been linked). -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 8041454..68d4d5f 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1482,9 +1482,6 @@ static unsigned kvm_page_table_hashfn(gfn_t gfn) static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *parent_pte) { - if (!parent_pte) - return; - pte_list_add(vcpu, parent_pte, &sp->parent_ptes); } @@ -1502,7 +1499,7 @@ static void drop_parent_pte(struct kvm_mmu_page *sp, } static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, - u64 *parent_pte, int direct) + int direct) { struct kvm_mmu_page *sp; sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache); @@ -1512,7 +1509,6 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, set_page_private(virt_to_page(sp->spt), (unsigned long)sp); list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); sp->parent_ptes = 0; - mmu_page_add_parent_pte(vcpu, sp, parent_pte); kvm_mod_used_mmu_pages(vcpu->kvm, +1); return sp; } @@ -1845,8 +1841,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, gva_t gaddr, unsigned level, int direct, - unsigned access, - u64 *parent_pte) + unsigned access) { union kvm_mmu_page_role role; unsigned quadrant; @@ -1876,19 +1871,15 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, if (sp->unsync && kvm_sync_page_transient(vcpu, sp)) break; - mmu_page_add_parent_pte(vcpu, sp, parent_pte); - if (sp->unsync_children) { + if (sp->unsync_children) kvm_make_request(KVM_REQ_MMU_SYNC, vcpu); - kvm_mmu_mark_parents_unsync(sp); - } else if (sp->unsync) - kvm_mmu_mark_parents_unsync(sp); __clear_sp_write_flooding_count(sp); trace_kvm_mmu_get_page(sp, false); return sp; } ++vcpu->kvm->stat.mmu_cache_miss; - sp = kvm_mmu_alloc_page(vcpu, parent_pte, direct); + sp = kvm_mmu_alloc_page(vcpu, direct); if (!sp) return sp; sp->gfn = gfn; @@ -1908,6 +1899,35 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, return sp; } +static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp) +{ + u64 spte; + + spte = __pa(sp->spt) | PT_PRESENT_MASK | PT_WRITABLE_MASK | + shadow_user_mask | shadow_x_mask | shadow_accessed_mask; + + mmu_spte_set(sptep, spte); +} + +static struct kvm_mmu_page * +mmu_spte_establish(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn, gva_t gaddr, + unsigned level, int direct, unsigned access) +{ + struct kvm_mmu_page *sp; + + WARN_ON(is_shadow_present_pte(*spte)); + + sp = kvm_mmu_get_page(vcpu, gfn, gaddr, level, direct, access); + + link_shadow_page(spte, sp); + mmu_page_add_parent_pte(vcpu, sp, spte); + + if (sp->unsync_children || sp->unsync) + kvm_mmu_mark_parents_unsync(sp); + + return sp; +} + static void shadow_walk_init(struct kvm_shadow_walk_iterator *iterator, struct kvm_vcpu *vcpu, u64 addr) { @@ -1957,16 +1977,6 @@ static void shadow_walk_next(struct kvm_shadow_walk_iterator *iterator) return __shadow_walk_next(iterator, *iterator->sptep); } -static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp) -{ - u64 spte; - - spte = __pa(sp->spt) | PT_PRESENT_MASK | PT_WRITABLE_MASK | - shadow_user_mask | shadow_x_mask | shadow_accessed_mask; - - mmu_spte_set(sptep, spte); -} - static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, unsigned direct_access) { @@ -2023,11 +2033,6 @@ static void kvm_mmu_page_unlink_children(struct kvm *kvm, mmu_page_zap_pte(kvm, sp, sp->spt + i); } -static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte) -{ - mmu_page_remove_parent_pte(sp, parent_pte); -} - static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp) { u64 *sptep; @@ -2582,9 +2587,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, bool prefault) { struct kvm_shadow_walk_iterator iterator; - struct kvm_mmu_page *sp; int emulate = 0; - gfn_t pseudo_gfn; for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) { if (iterator.level == level) { @@ -2602,12 +2605,11 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, u64 base_addr = iterator.addr; base_addr &= PT64_LVL_ADDR_MASK(iterator.level); - pseudo_gfn = base_addr >> PAGE_SHIFT; - sp = kvm_mmu_get_page(vcpu, pseudo_gfn, iterator.addr, - iterator.level - 1, - 1, ACC_ALL, iterator.sptep); + mmu_spte_establish(vcpu, iterator.sptep, + gpa_to_gfn(base_addr), + iterator.addr, iterator.level - 1, + 1, ACC_ALL); - link_shadow_page(iterator.sptep, sp); } } return emulate; @@ -2926,7 +2928,7 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); sp = kvm_mmu_get_page(vcpu, 0, 0, PT64_ROOT_LEVEL, - 1, ACC_ALL, NULL); + 1, ACC_ALL); ++sp->root_count; spin_unlock(&vcpu->kvm->mmu_lock); vcpu->arch.mmu.root_hpa = __pa(sp->spt); @@ -2939,8 +2941,7 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) kvm_mmu_free_some_pages(vcpu); sp = kvm_mmu_get_page(vcpu, i << (30 - PAGE_SHIFT), i << 30, - PT32_ROOT_LEVEL, 1, ACC_ALL, - NULL); + PT32_ROOT_LEVEL, 1, ACC_ALL); root = __pa(sp->spt); ++sp->root_count; spin_unlock(&vcpu->kvm->mmu_lock); @@ -2977,7 +2978,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, - 0, ACC_ALL, NULL); + 0, ACC_ALL); root = __pa(sp->spt); ++sp->root_count; spin_unlock(&vcpu->kvm->mmu_lock); @@ -3012,7 +3013,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) kvm_mmu_free_some_pages(vcpu); sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, PT32_ROOT_LEVEL, 0, - ACC_ALL, NULL); + ACC_ALL); root = __pa(sp->spt); ++sp->root_count; spin_unlock(&vcpu->kvm->mmu_lock); diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 105dd5b..3605ff7 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -434,8 +434,9 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, sp = NULL; if (!is_shadow_present_pte(*it.sptep)) { table_gfn = gw->table_gfn[it.level - 2]; - sp = kvm_mmu_get_page(vcpu, table_gfn, addr, it.level-1, - false, access, it.sptep); + sp = mmu_spte_establish(vcpu, it.sptep, table_gfn, + addr, it.level-1, false, + access); } /* @@ -444,9 +445,6 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, */ if (FNAME(gpte_changed)(vcpu, gw, it.level - 1)) goto out_gpte_changed; - - if (sp) - link_shadow_page(it.sptep, sp); } for (; @@ -464,9 +462,8 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, direct_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1); - sp = kvm_mmu_get_page(vcpu, direct_gfn, addr, it.level-1, - true, direct_access, it.sptep); - link_shadow_page(it.sptep, sp); + mmu_spte_establish(vcpu, it.sptep, direct_gfn, addr, + it.level-1, true, direct_access); } clear_sp_write_flooding_count(it.sptep); @@ -478,7 +475,8 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, out_gpte_changed: if (sp) - kvm_mmu_put_page(sp, it.sptep); + drop_parent_pte(sp, it.sptep); + kvm_release_pfn_clean(pfn); return 0; }
There is little different between walking parent pte and walking ramp: all spte in rmap must be present but this is not true on parent pte list, in kvm_mmu_alloc_page, we always link the parent list before set the spte to present This patch introduce mmu_spte_establish which set the spte before linking it to parent list to eliminates the different then it is possible to unify the code of walking pte list Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> --- arch/x86/kvm/mmu.c | 81 ++++++++++++++++++++++--------------------- arch/x86/kvm/paging_tmpl.h | 16 ++++----- 2 files changed, 48 insertions(+), 49 deletions(-)