* remove redundant VM Exit for non-aligned guest pte write or part of pte write.
@ 2007-12-20 8:51 Dong, Eddie
[not found] ` <10EA09EFD8728347A513008B6B0DA77A028A6DB2-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
0 siblings, 1 reply; 6+ messages in thread
From: Dong, Eddie @ 2007-12-20 8:51 UTC (permalink / raw)
To: kvm-devel
[-- Attachment #1: Type: text/plain, Size: 3915 bytes --]
I observed 1-2 seconds faster in Windows XPSP2 ACPI bootup with total of
23 seconds.
I can;t say it is exactly caused by this patch, but anyway it simplifies
the logic and
code w/o any additional complexity.
thx,eddie
A guest non-aligned pte write or part of pte
update will leave shadow_trap_nonpresent_pte
in spte, which expects a new VM Exit at next
access time.
This patch fixed this by reading guest pte
in advance and thus be able to update spte
and reduce next VM Exit.
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 401eb7c..b2fd336 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1285,8 +1285,7 @@ static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu,
static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
struct kvm_mmu_page *sp,
u64 *spte,
- const void *new, int bytes,
- int offset_in_pte)
+ const void *new)
{
if (sp->role.level != PT_PAGE_TABLE_LEVEL) {
++vcpu->kvm->stat.mmu_pde_zapped;
@@ -1295,9 +1294,9 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu,
++vcpu->kvm->stat.mmu_pte_updated;
if (sp->role.glevels == PT32_ROOT_LEVEL)
- paging32_update_pte(vcpu, sp, spte, new, bytes,
offset_in_pte);
+ paging32_update_pte(vcpu, sp, spte, new);
else
- paging64_update_pte(vcpu, sp, spte, new, bytes,
offset_in_pte);
+ paging64_update_pte(vcpu, sp, spte, new);
}
static bool need_remote_flush(u64 old, u64 new)
@@ -1336,8 +1335,8 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu,
gpa_t gpa,
struct hlist_node *node, *n;
struct hlist_head *bucket;
unsigned index;
- u64 entry;
- u64 *spte;
+ u64 entry, gentry;
+ u64 *spte, *gpte;
unsigned offset = offset_in_page(gpa);
unsigned pte_size;
unsigned page_offset;
@@ -1346,6 +1345,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu,
gpa_t gpa,
int level;
int flooded = 0;
int npte;
+ int r;
pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes);
++vcpu->kvm->stat.mmu_pte_write;
@@ -1406,11 +1406,19 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu,
gpa_t gpa,
continue;
}
spte = &sp->spt[page_offset / sizeof(*spte)];
+ if ((gpa & (pte_size - 1)) || (bytes < pte_size)) {
+ gentry = 0;
+ gpte = &gentry;
+ r = kvm_read_guest(vcpu->kvm, gpa & ~(pte_size -
1),
+ gpte, pte_size);
+ if (r < 0)
+ continue;
+ } else
+ gpte = new;
while (npte--) {
entry = *spte;
mmu_pte_write_zap_pte(vcpu, sp, spte);
- mmu_pte_write_new_pte(vcpu, sp, spte, new,
bytes,
- page_offset & (pte_size -
1));
+ mmu_pte_write_new_pte(vcpu, sp, spte, gpte);
mmu_pte_write_flush_tlb(vcpu, entry, *spte);
++spte;
}
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 56b88f7..4e4d859 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -240,20 +240,17 @@ err:
}
static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct
kvm_mmu_page *page,
- u64 *spte, const void *pte, int bytes,
- int offset_in_pte)
+ u64 *spte, const void *pte)
{
pt_element_t gpte;
unsigned pte_access;
gpte = *(const pt_element_t *)pte;
if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) {
- if (!offset_in_pte && !is_present_pte(gpte))
+ if (!is_present_pte(gpte))
set_shadow_pte(spte,
shadow_notrap_nonpresent_pte);
return;
}
- if (bytes < sizeof(pt_element_t))
- return;
pgprintk("%s: gpte %llx spte %p\n", __FUNCTION__, (u64)gpte,
spte);
pte_access = page->role.access & FNAME(gpte_access)(vcpu, gpte);
mmu_set_spte(vcpu, spte, page->role.access, pte_access, 0, 0,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
[-- Attachment #2: tlb-clean3.patch --]
[-- Type: application/octet-stream, Size: 3526 bytes --]
A guest non-aligned pte write or part of pte
update will leave shadow_trap_nonpresent_pte
in spte, which expects a new VM Exit at next
access time.
This patch fixed this by reading guest pte
in advance and thus be able to update spte
and reduce next VM Exit.
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 401eb7c..b2fd336 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1285,8 +1285,7 @@ static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu,
static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
struct kvm_mmu_page *sp,
u64 *spte,
- const void *new, int bytes,
- int offset_in_pte)
+ const void *new)
{
if (sp->role.level != PT_PAGE_TABLE_LEVEL) {
++vcpu->kvm->stat.mmu_pde_zapped;
@@ -1295,9 +1294,9 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
++vcpu->kvm->stat.mmu_pte_updated;
if (sp->role.glevels == PT32_ROOT_LEVEL)
- paging32_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte);
+ paging32_update_pte(vcpu, sp, spte, new);
else
- paging64_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte);
+ paging64_update_pte(vcpu, sp, spte, new);
}
static bool need_remote_flush(u64 old, u64 new)
@@ -1336,8 +1335,8 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
struct hlist_node *node, *n;
struct hlist_head *bucket;
unsigned index;
- u64 entry;
- u64 *spte;
+ u64 entry, gentry;
+ u64 *spte, *gpte;
unsigned offset = offset_in_page(gpa);
unsigned pte_size;
unsigned page_offset;
@@ -1346,6 +1345,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
int level;
int flooded = 0;
int npte;
+ int r;
pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes);
++vcpu->kvm->stat.mmu_pte_write;
@@ -1406,11 +1406,19 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
continue;
}
spte = &sp->spt[page_offset / sizeof(*spte)];
+ if ((gpa & (pte_size - 1)) || (bytes < pte_size)) {
+ gentry = 0;
+ gpte = &gentry;
+ r = kvm_read_guest(vcpu->kvm, gpa & ~(pte_size - 1),
+ gpte, pte_size);
+ if (r < 0)
+ continue;
+ } else
+ gpte = new;
while (npte--) {
entry = *spte;
mmu_pte_write_zap_pte(vcpu, sp, spte);
- mmu_pte_write_new_pte(vcpu, sp, spte, new, bytes,
- page_offset & (pte_size - 1));
+ mmu_pte_write_new_pte(vcpu, sp, spte, gpte);
mmu_pte_write_flush_tlb(vcpu, entry, *spte);
++spte;
}
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 56b88f7..4e4d859 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -240,20 +240,17 @@ err:
}
static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
- u64 *spte, const void *pte, int bytes,
- int offset_in_pte)
+ u64 *spte, const void *pte)
{
pt_element_t gpte;
unsigned pte_access;
gpte = *(const pt_element_t *)pte;
if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) {
- if (!offset_in_pte && !is_present_pte(gpte))
+ if (!is_present_pte(gpte))
set_shadow_pte(spte, shadow_notrap_nonpresent_pte);
return;
}
- if (bytes < sizeof(pt_element_t))
- return;
pgprintk("%s: gpte %llx spte %p\n", __FUNCTION__, (u64)gpte, spte);
pte_access = page->role.access & FNAME(gpte_access)(vcpu, gpte);
mmu_set_spte(vcpu, spte, page->role.access, pte_access, 0, 0,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
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^ permalink raw reply related [flat|nested] 6+ messages in thread[parent not found: <10EA09EFD8728347A513008B6B0DA77A028A6DB2-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>]
* Re: remove redundant VM Exit for non-aligned guest pte write or part of pte write. [not found] ` <10EA09EFD8728347A513008B6B0DA77A028A6DB2-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org> @ 2007-12-20 9:21 ` Avi Kivity [not found] ` <476A3436.1000900-atKUWr5tajBWk0Htik3J/w@public.gmane.org> 0 siblings, 1 reply; 6+ messages in thread From: Avi Kivity @ 2007-12-20 9:21 UTC (permalink / raw) To: Dong, Eddie; +Cc: kvm-devel Dong, Eddie wrote: > I observed 1-2 seconds faster in Windows XPSP2 ACPI bootup with total of > 23 seconds. > I can;t say it is exactly caused by this patch, but anyway it simplifies > the logic and > code w/o any additional complexity. > thx,eddie > > > Patch looks good, but will delay so that the guest scaling patch can be merged. kvm_read_guest() will need to change to kvm_read_guest_inatomic(), since the mmu is becoming spinlocked. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic. ------------------------------------------------------------------------- SF.Net email is sponsored by: Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace ^ permalink raw reply [flat|nested] 6+ messages in thread
[parent not found: <476A3436.1000900-atKUWr5tajBWk0Htik3J/w@public.gmane.org>]
* Re: remove redundant VM Exit for non-aligned guest pte write or part of pte write. [not found] ` <476A3436.1000900-atKUWr5tajBWk0Htik3J/w@public.gmane.org> @ 2008-01-04 6:14 ` Dong, Eddie [not found] ` <10EA09EFD8728347A513008B6B0DA77A029B5503-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org> 0 siblings, 1 reply; 6+ messages in thread From: Dong, Eddie @ 2008-01-04 6:14 UTC (permalink / raw) To: Avi Kivity; +Cc: kvm-devel [-- Attachment #1: Type: text/plain, Size: 4206 bytes --] Avi Kivity wrote: > Dong, Eddie wrote: >> I observed 1-2 seconds faster in Windows XPSP2 ACPI bootup with >> total of 23 seconds. >> I can;t say it is exactly caused by this patch, but anyway it >> simplifies the logic and code w/o any additional complexity. >> thx,eddie >> >> >> > > Patch looks good, but will delay so that the guest scaling patch can > be merged. kvm_read_guest() will need to change to > kvm_read_guest_inatomic(), since the mmu is becoming spinlocked. Rebased. Thx, eddie A guest non-aligned pte write or part of pte update will leave shadow_trap_nonpresent_pte in spte, which expects a new VM Exit at next access time. This patch fixed this by reading guest pte in advance and thus be able to update spte and reduce next VM Exit. Signed-off-by: Yaozu (Eddie) Dong <eddie.dong-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index c478ee2..644254a 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1309,8 +1309,7 @@ static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu, static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *spte, - const void *new, int bytes, - int offset_in_pte) + const void *new) { if (sp->role.level != PT_PAGE_TABLE_LEVEL) { ++vcpu->kvm->stat.mmu_pde_zapped; @@ -1319,9 +1318,9 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, ++vcpu->kvm->stat.mmu_pte_updated; if (sp->role.glevels == PT32_ROOT_LEVEL) - paging32_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); + paging32_update_pte(vcpu, sp, spte, new); else - paging64_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); + paging64_update_pte(vcpu, sp, spte, new); } static bool need_remote_flush(u64 old, u64 new) @@ -1397,8 +1396,8 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, struct hlist_node *node, *n; struct hlist_head *bucket; unsigned index; - u64 entry; - u64 *spte; + u64 entry, gentry; + u64 *spte, *gpte; unsigned offset = offset_in_page(gpa); unsigned pte_size; unsigned page_offset; @@ -1407,6 +1406,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, int level; int flooded = 0; int npte; + int r; pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes); mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes); @@ -1470,11 +1470,20 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, continue; } spte = &sp->spt[page_offset / sizeof(*spte)]; + if ((gpa & (pte_size - 1)) || (bytes < pte_size)) { + gentry = 0; + gpte = &gentry; + r = kvm_read_guest_atomic(vcpu->kvm, + gpa & ~(pte_size - 1), + gpte, pte_size); + if (r < 0) + continue; + } else + gpte = (u64 *)new; while (npte--) { entry = *spte; mmu_pte_write_zap_pte(vcpu, sp, spte); - mmu_pte_write_new_pte(vcpu, sp, spte, new, bytes, - page_offset & (pte_size - 1)); + mmu_pte_write_new_pte(vcpu, sp, spte, gpte); mmu_pte_write_flush_tlb(vcpu, entry, *spte); ++spte; } diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 03ba860..1678071 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -240,8 +240,7 @@ err: } static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page, - u64 *spte, const void *pte, int bytes, - int offset_in_pte) + u64 *spte, const void *pte) { pt_element_t gpte; unsigned pte_access; @@ -249,12 +248,10 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page, gpte = *(const pt_element_t *)pte; if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) { - if (!offset_in_pte && !is_present_pte(gpte)) + if (!is_present_pte(gpte)) set_shadow_pte(spte, shadow_notrap_nonpresent_pte); return; } - if (bytes < sizeof(pt_element_t)) - return; pgprintk("%s: gpte %llx spte %p\n", __FUNCTION__, (u64)gpte, spte); pte_access = page->role.access & FNAME(gpte_access)(vcpu, gpte); if (gpte_to_gfn(gpte) != vcpu->arch.update_pte.gfn) [-- Attachment #2: tlb-prefetch.patch2 --] [-- Type: application/octet-stream, Size: 1522 bytes --] diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 56b88f7..8b53234 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -424,7 +424,7 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) { int i, offset = 0; - pt_element_t *gpt; + pt_element_t *gpt, now; struct page *page; if (sp->role.metaphysical @@ -437,11 +437,24 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu, offset = sp->role.quadrant << PT64_LEVEL_BITS; page = gfn_to_page(vcpu->kvm, sp->gfn); gpt = kmap_atomic(page, KM_USER0); - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) - if (is_present_pte(gpt[offset + i])) + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + now = gpt[offset + i]; + if (is_present_pte(now)) { sp->spt[i] = shadow_trap_nonpresent_pte; - else + if (sp->role.level == PT_PAGE_TABLE_LEVEL) { + kunmap_atomic(gpt, KM_USER0); + if (mmu_topup_memory_cache( + &vcpu->arch.mmu_rmap_desc_cache, + rmap_desc_cache, 1)) + continue; + FNAME(update_pte)(vcpu, sp, + &sp->spt[i], &now, + sizeof(now), 0); + gpt = kmap_atomic(page, KM_USER0); + } + } else sp->spt[i] = shadow_notrap_nonpresent_pte; + } kunmap_atomic(gpt, KM_USER0); kvm_release_page_clean(page); } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c [-- Attachment #3: Type: text/plain, Size: 228 bytes --] ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ [-- Attachment #4: Type: text/plain, Size: 186 bytes --] _______________________________________________ kvm-devel mailing list kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org https://lists.sourceforge.net/lists/listinfo/kvm-devel ^ permalink raw reply related [flat|nested] 6+ messages in thread
[parent not found: <10EA09EFD8728347A513008B6B0DA77A029B5503-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>]
* Re: remove redundant VM Exit for non-aligned guest pte write or part of pte write. [not found] ` <10EA09EFD8728347A513008B6B0DA77A029B5503-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org> @ 2008-01-06 8:50 ` Avi Kivity [not found] ` <47809670.9090706-atKUWr5tajBWk0Htik3J/w@public.gmane.org> 0 siblings, 1 reply; 6+ messages in thread From: Avi Kivity @ 2008-01-06 8:50 UTC (permalink / raw) To: Dong, Eddie; +Cc: kvm-devel Dong, Eddie wrote: > Avi Kivity wrote: > >> Dong, Eddie wrote: >> >>> I observed 1-2 seconds faster in Windows XPSP2 ACPI bootup with >>> total of 23 seconds. >>> I can;t say it is exactly caused by this patch, but anyway it >>> simplifies the logic and code w/o any additional complexity. >>> thx,eddie >>> >>> >>> >>> >> Patch looks good, but will delay so that the guest scaling patch can >> be merged. kvm_read_guest() will need to change to >> kvm_read_guest_inatomic(), since the mmu is becoming spinlocked. >> > > Rebased. > Thx, eddie > > A guest non-aligned pte write or part of pte > update will leave shadow_trap_nonpresent_pte > in spte, which expects a new VM Exit at next > access time. > > This patch fixed this by reading guest pte > in advance and thus be able to update spte > and reduce next VM Exit. > > Wrong patch attached... -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ ^ permalink raw reply [flat|nested] 6+ messages in thread
[parent not found: <47809670.9090706-atKUWr5tajBWk0Htik3J/w@public.gmane.org>]
* Re: remove redundant VM Exit for non-aligned guest pte write or part of pte write. [not found] ` <47809670.9090706-atKUWr5tajBWk0Htik3J/w@public.gmane.org> @ 2008-01-06 13:59 ` Dong, Eddie [not found] ` <10EA09EFD8728347A513008B6B0DA77A029B57CD-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org> 0 siblings, 1 reply; 6+ messages in thread From: Dong, Eddie @ 2008-01-06 13:59 UTC (permalink / raw) To: Avi Kivity; +Cc: kvm-devel [-- Attachment #1: Type: text/plain, Size: 73 bytes --] > Wrong patch attached... Sorry for the wrong attachment :( Eddie [-- Attachment #2: tlb-clean3.patch2 --] [-- Type: application/octet-stream, Size: 3534 bytes --] A guest non-aligned pte write or part of pte update will leave shadow_trap_nonpresent_pte in spte, which expects a new VM Exit at next access time. This patch fixed this by reading guest pte in advance and thus be able to update spte and reduce next VM Exit. Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index c478ee2..644254a 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1309,8 +1309,7 @@ static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu, static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *spte, - const void *new, int bytes, - int offset_in_pte) + const void *new) { if (sp->role.level != PT_PAGE_TABLE_LEVEL) { ++vcpu->kvm->stat.mmu_pde_zapped; @@ -1319,9 +1318,9 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, ++vcpu->kvm->stat.mmu_pte_updated; if (sp->role.glevels == PT32_ROOT_LEVEL) - paging32_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); + paging32_update_pte(vcpu, sp, spte, new); else - paging64_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); + paging64_update_pte(vcpu, sp, spte, new); } static bool need_remote_flush(u64 old, u64 new) @@ -1397,8 +1396,8 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, struct hlist_node *node, *n; struct hlist_head *bucket; unsigned index; - u64 entry; - u64 *spte; + u64 entry, gentry; + u64 *spte, *gpte; unsigned offset = offset_in_page(gpa); unsigned pte_size; unsigned page_offset; @@ -1407,6 +1406,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, int level; int flooded = 0; int npte; + int r; pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes); mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes); @@ -1470,11 +1470,20 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, continue; } spte = &sp->spt[page_offset / sizeof(*spte)]; + if ((gpa & (pte_size - 1)) || (bytes < pte_size)) { + gentry = 0; + gpte = &gentry; + r = kvm_read_guest_atomic(vcpu->kvm, + gpa & ~(pte_size - 1), + gpte, pte_size); + if (r < 0) + continue; + } else + gpte = (u64 *)new; while (npte--) { entry = *spte; mmu_pte_write_zap_pte(vcpu, sp, spte); - mmu_pte_write_new_pte(vcpu, sp, spte, new, bytes, - page_offset & (pte_size - 1)); + mmu_pte_write_new_pte(vcpu, sp, spte, gpte); mmu_pte_write_flush_tlb(vcpu, entry, *spte); ++spte; } diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 03ba860..1678071 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -240,8 +240,7 @@ err: } static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page, - u64 *spte, const void *pte, int bytes, - int offset_in_pte) + u64 *spte, const void *pte) { pt_element_t gpte; unsigned pte_access; @@ -249,12 +248,10 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page, gpte = *(const pt_element_t *)pte; if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) { - if (!offset_in_pte && !is_present_pte(gpte)) + if (!is_present_pte(gpte)) set_shadow_pte(spte, shadow_notrap_nonpresent_pte); return; } - if (bytes < sizeof(pt_element_t)) - return; pgprintk("%s: gpte %llx spte %p\n", __FUNCTION__, (u64)gpte, spte); pte_access = page->role.access & FNAME(gpte_access)(vcpu, gpte); if (gpte_to_gfn(gpte) != vcpu->arch.update_pte.gfn) [-- Attachment #3: Type: text/plain, Size: 228 bytes --] ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ [-- Attachment #4: Type: text/plain, Size: 186 bytes --] _______________________________________________ kvm-devel mailing list kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org https://lists.sourceforge.net/lists/listinfo/kvm-devel ^ permalink raw reply related [flat|nested] 6+ messages in thread
[parent not found: <10EA09EFD8728347A513008B6B0DA77A029B57CD-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>]
* Re: remove redundant VM Exit for non-aligned guest pte write or part of pte write. [not found] ` <10EA09EFD8728347A513008B6B0DA77A029B57CD-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org> @ 2008-01-07 9:15 ` Avi Kivity 0 siblings, 0 replies; 6+ messages in thread From: Avi Kivity @ 2008-01-07 9:15 UTC (permalink / raw) To: Dong, Eddie; +Cc: kvm-devel Dong, Eddie wrote: >> Wrong patch attached... >> > > Sorry for the wrong attachment :( > Applied, thanks. I fixed the error case -- you can't 'continue', you still need to zap the pte and flush the tlb. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ ^ permalink raw reply [flat|nested] 6+ messages in thread
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2007-12-20 8:51 remove redundant VM Exit for non-aligned guest pte write or part of pte write Dong, Eddie
[not found] ` <10EA09EFD8728347A513008B6B0DA77A028A6DB2-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-12-20 9:21 ` Avi Kivity
[not found] ` <476A3436.1000900-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2008-01-04 6:14 ` Dong, Eddie
[not found] ` <10EA09EFD8728347A513008B6B0DA77A029B5503-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2008-01-06 8:50 ` Avi Kivity
[not found] ` <47809670.9090706-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2008-01-06 13:59 ` Dong, Eddie
[not found] ` <10EA09EFD8728347A513008B6B0DA77A029B57CD-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2008-01-07 9:15 ` Avi Kivity
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