From ce095724dd15a17215a4e04453dc322dac77d8db Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Thu, 12 Jun 2008 16:11:39 +0100 Subject: [PATCH] x86: add perf counter for pointless updates of writable pages through a hypercall Signed-off-by: Jan Beulich --- xen/arch/x86/mm.c | 2 ++ xen/include/asm-x86/perfc_defn.h | 1 + 2 files changed, 3 insertions(+) diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c index 9ab765da86..514d667715 100644 --- a/xen/arch/x86/mm.c +++ b/xen/arch/x86/mm.c @@ -2602,6 +2602,8 @@ int do_mmu_update( if ( unlikely(!get_page_type(page, PGT_writable_page)) ) break; + perfc_incr(writable_mmu_updates); + okay = paging_write_guest_entry(v, va, req.val, _mfn(mfn)); put_page_type(page); diff --git a/xen/include/asm-x86/perfc_defn.h b/xen/include/asm-x86/perfc_defn.h index 0bc2515b91..6012db35d2 100644 --- a/xen/include/asm-x86/perfc_defn.h +++ b/xen/include/asm-x86/perfc_defn.h @@ -23,6 +23,7 @@ PERFCOUNTER(calls_to_mmuext_op, "calls to mmuext_op") PERFCOUNTER(num_mmuext_ops, "mmuext ops") PERFCOUNTER(calls_to_mmu_update, "calls to mmu_update") PERFCOUNTER(num_page_updates, "page updates") +PERFCOUNTER(writable_mmu_updates, "mmu_updates of writable pages") PERFCOUNTER(calls_to_update_va, "calls to update_va_map") PERFCOUNTER(page_faults, "page faults") PERFCOUNTER(copy_user_faults, "copy_user faults") -- 2.30.2