memory: Don't update all memory region when ioeventfd changed
commit4dc56152237f61694fa42675a78ffd14a509df98
authorGonglei <arei.gonglei@huawei.com>
Thu, 8 May 2014 03:47:32 +0000 (8 11:47 +0800)
committerPaolo Bonzini <pbonzini@redhat.com>
Tue, 17 Jun 2014 14:07:37 +0000 (17 16:07 +0200)
tree0edbaa91512ac1de8593534c4f83065db25de9a1
parentb0e56e0b63f350691b52d3e75e89bb64143fbeff
memory: Don't update all memory region when ioeventfd changed

memory mappings don't rely on ioeventfds, there is no need
to destroy and rebuild them when manipulating ioeventfds,
otherwise it scarifies performance.

according to testing result, each ioeventfd deleing needs
about 5ms, within which memory mapping rebuilding needs
about 4ms. With many Nics and vmchannel in a VM doing migrating,
there can be many ioeventfds deleting which increasing
downtime remarkably.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Herongguang <herongguang.he@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memory.c