]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
KVM: VMX: Only save/restore MSR_K6_STAR if necessary
authorAvi Kivity <avi@qumranet.com>
Thu, 19 Apr 2007 11:28:44 +0000 (14:28 +0300)
committerAvi Kivity <avi@qumranet.com>
Thu, 3 May 2007 07:52:30 +0000 (10:52 +0300)
commit4d56c8a787aefb2e3fc4ac4be966db96c14d1ad8
tree99db1bc065832b2685bd5edb75cd7c1019011ead
parent35cc7f971188366f5a5c0d5da1456bb38cef5da9
KVM: VMX: Only save/restore MSR_K6_STAR if necessary

Intel hosts only support syscall/sysret in long more (and only if efer.sce
is enabled), so only reload the related MSR_K6_STAR if the guest will
actually be able to use it.

This reduces vmexit cost by about 500 cycles (6400 -> 5870) on my setup.

Signed-off-by: Avi Kivity <avi@qumranet.com>
drivers/kvm/vmx.c