KVM: MMU: zap pages in batch
Zap at lease 10 pages before releasing mmu-lock to reduce the overload
caused by requiring lock
After the patch, kvm_zap_obsolete_pages can forward progress anyway,
so update the comments
[ It improves the case 0.6% ~ 1% that do kernel building meanwhile read
PCI ROM. ]
Note: i am not sure that "10" is the best speculative value, i just
guessed that '10' can make vcpu do not spend long time on
kvm_zap_obsolete_pages and do not cause mmu-lock too hungry.
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
1 file changed