xen/PMU: Initialization code for Xen PMU
Map shared data structure that will hold CPU registers, VPMU context,
V/PCPU IDs of the CPU interrupted by PMU interrupt. Hypervisor fills
this information in its handler and passes it to the guest for further
processing.
Set up PMU VIRQ.
Now that perf infrastructure will assume that PMU is available on a PV
guest we need to be careful and make sure that accesses via RDPMC
instruction don't cause fatal traps by the hypervisor. Provide a nop
RDPMC handler.
For the same reason avoid issuing a warning on a write to APIC's LVTPC.
Both of these will be made functional in later patches.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 373dbc9..19072f9 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -84,6 +84,7 @@
#include "mmu.h"
#include "smp.h"
#include "multicalls.h"
+#include "pmu.h"
EXPORT_SYMBOL_GPL(hypercall_page);
@@ -1082,6 +1083,11 @@
return ret;
}
+unsigned long long xen_read_pmc(int counter)
+{
+ return 0;
+}
+
void xen_setup_shared_info(void)
{
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
@@ -1216,7 +1222,7 @@
.write_msr = xen_write_msr_safe,
.read_tsc = native_read_tsc,
- .read_pmc = native_read_pmc,
+ .read_pmc = xen_read_pmc,
.read_tscp = native_read_tscp,
@@ -1267,6 +1273,10 @@
static void xen_reboot(int reason)
{
struct sched_shutdown r = { .reason = reason };
+ int cpu;
+
+ for_each_online_cpu(cpu)
+ xen_pmu_finish(cpu);
if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
BUG();