lkml.org 
[lkml]   [2010]   [May]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 2/5] KVM: MMU: split the operations of kvm_mmu_zap_page()
Using kvm_mmu_prepare_zap_page() and kvm_mmu_commit_zap_page() to
split kvm_mmu_zap_page() function, then we can:

- traverse hlist safely
- easily to gather remote tlb flush which occurs during page zapped

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/mmu.c | 42 ++++++++++++++++++++++++++++++++++++++-
arch/x86/kvm/x86.c | 1 +
3 files changed, 43 insertions(+), 1 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 0cd0f29..e4df1cf 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -388,6 +388,7 @@ struct kvm_arch {
* Hash table of struct kvm_mmu_page.
*/
struct list_head active_mmu_pages;
+ struct list_head invalid_mmu_pages;
struct list_head assigned_dev_head;
struct iommu_domain *iommu_domain;
int iommu_flags;
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 84c705e..0c957bf 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -915,6 +915,7 @@ static int is_empty_shadow_page(u64 *spt)
static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp)
{
ASSERT(is_empty_shadow_page(sp->spt));
+ hlist_del(&sp->hash_link);
list_del(&sp->link);
__free_page(virt_to_page(sp->spt));
if (!sp->role.direct)
@@ -1560,6 +1561,46 @@ static int mmu_zap_unsync_children(struct kvm *kvm,
return zapped;
}

+static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
+{
+ int ret;
+
+ trace_kvm_mmu_zap_page(sp);
+ ++kvm->stat.mmu_shadow_zapped;
+ ret = mmu_zap_unsync_children(kvm, sp);
+ kvm_mmu_page_unlink_children(kvm, sp);
+ kvm_mmu_unlink_parents(kvm, sp);
+ if (!sp->role.invalid && !sp->role.direct)
+ unaccount_shadowed(kvm, sp->gfn);
+ if (sp->unsync)
+ kvm_unlink_unsync_page(kvm, sp);
+ if (!sp->root_count)
+ /* Count self */
+ ret++;
+ else
+ kvm_reload_remote_mmus(kvm);
+
+ sp->role.invalid = 1;
+ list_move(&sp->link, &kvm->arch.invalid_mmu_pages);
+ kvm_mmu_reset_last_pte_updated(kvm);
+ return ret;
+}
+
+static void kvm_mmu_commit_zap_page(struct kvm *kvm)
+{
+ struct kvm_mmu_page *sp, *n;
+
+ if (list_empty(&kvm->arch.invalid_mmu_pages))
+ return;
+
+ kvm_flush_remote_tlbs(kvm);
+ list_for_each_entry_safe(sp, n, &kvm->arch.invalid_mmu_pages, link) {
+ WARN_ON(!sp->role.invalid);
+ if (!sp->root_count)
+ kvm_mmu_free_page(kvm, sp);
+ }
+}
+
static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
{
int ret;
@@ -1577,7 +1618,6 @@ static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
if (!sp->root_count) {
/* Count self */
ret++;
- hlist_del(&sp->hash_link);
kvm_mmu_free_page(kvm, sp);
} else {
sp->role.invalid = 1;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5e5cd8d..225c3c4 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5331,6 +5331,7 @@ struct kvm *kvm_arch_create_vm(void)
}

INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
+ INIT_LIST_HEAD(&kvm->arch.invalid_mmu_pages);
INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);

/* Reserve bit 0 of irq_sources_bitmap for userspace irq source */
--
1.6.1.2




\
 
 \ /
  Last update: 2010-05-30 14:43    [W:0.240 / U:0.012 seconds]
©2003-2014 Jasper Spaans. Advertise on this site