Jan Beulich
2008-Jun-12 14:36 UTC
[Xen-devel] [PATCH] x86: add perf counter for pointless updates of writable pages through a hypercall
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Index: 2008-06-12/xen/arch/x86/mm.c
==================================================================---
2008-06-12.orig/xen/arch/x86/mm.c 2008-06-12 09:04:50.000000000 +0200
+++ 2008-06-12/xen/arch/x86/mm.c 2008-06-12 09:08:36.000000000 +0200
@@ -2606,6 +2606,8 @@ 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);
Index: 2008-06-12/xen/include/asm-x86/perfc_defn.h
==================================================================---
2008-06-12.orig/xen/include/asm-x86/perfc_defn.h 2008-06-10 18:00:41.000000000
+0200
+++ 2008-06-12/xen/include/asm-x86/perfc_defn.h 2008-06-12 09:08:36.000000000
+0200
@@ -23,6 +23,7 @@ PERFCOUNTER(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_update-s 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")
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel