2015-04-10 19:51:05

by Radim Krčmář

[permalink] [raw]
Subject: [PATCH] KVM: reuse memslot in kvm_write_guest_page

Saves one O(log N) search.

Signed-off-by: Radim Krčmář <[email protected]>
---
I'm still not sure how to bridge the gap between the code we have and
the code I want, but all routes so far contained this change. Notice
that we use '_memslot' and '_in_slot' suffix for the same meaning ...
(And the completely useless 'kvm' parameter for page dirtying.)

virt/kvm/kvm_main.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 91a36e21c0fb..09cf409b0389 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1589,15 +1589,17 @@ int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
int offset, int len)
{
int r;
+ struct kvm_memory_slot *memslot;
unsigned long addr;

- addr = gfn_to_hva(kvm, gfn);
+ memslot = gfn_to_memslot(kvm, gfn);
+ addr = gfn_to_hva_memslot(memslot, gfn);
if (kvm_is_error_hva(addr))
return -EFAULT;
r = __copy_to_user((void __user *)addr + offset, data, len);
if (r)
return -EFAULT;
- mark_page_dirty(kvm, gfn);
+ mark_page_dirty_in_slot(kvm, memslot, gfn);
return 0;
}
EXPORT_SYMBOL_GPL(kvm_write_guest_page);
--
2.3.5