From: Mukesh Rathor <[email protected]> We also optimize one - the TLB flush. The native operation would needlessly IPI offline VCPUs causing extra wakeups. Using the Xen one avoids that and lets the hypervisor determine which VCPU needs the TLB flush.
Signed-off-by: Mukesh Rathor <[email protected]> Signed-off-by: Konrad Rzeszutek Wilk <[email protected]> --- arch/x86/xen/mmu.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 490ddb3..c1d406f 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -2222,6 +2222,15 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { void __init xen_init_mmu_ops(void) { x86_init.paging.pagetable_init = xen_pagetable_init; + + /* Optimization - we can use the HVM one but it has no idea which + * VCPUs are descheduled - which means that it will needlessly IPI + * them. Xen knows so let it do the job. + */ + if (xen_feature(XENFEAT_auto_translated_physmap)) { + pv_mmu_ops.flush_tlb_others = xen_flush_tlb_others; + return; + } pv_mmu_ops = xen_mmu_ops; memset(dummy_mapping, 0xff, PAGE_SIZE); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
