xenoprof: Fix more than one events can't be sampled concurrently for Intel CPU with...

The original code only sets EN bit of IA32_PERFEVTSEL0 when profiling
is started.

Signed-off-by: Xiaowei Yang <xiaowei.yang@intel.com>

diff --git a/xen/arch/x86/oprofile/op_model_ppro.c b/xen/arch/x86/oprofile/op_model_ppro.c
index 6c4344ee214efbc3f10ed3b28b31e3ef6cda8964..53ff2182c2cb113e14d29df3f50464bb615af74b 100644 (file)
--- a/xen/arch/x86/oprofile/op_model_ppro.c
+++ b/xen/arch/x86/oprofile/op_model_ppro.c
@@ -104,6 +104,8 @@ static int ppro_check_ctrs(unsigned int const cpu,
        int mode = xenoprofile_get_mode(current, regs);
 
        for (i = 0 ; i < NUM_COUNTERS; ++i) {
+               if (!reset_value[i])
+                       continue;
                CTR_READ(low, high, msrs, i);
                if (CTR_OVERFLOWED(low)) {
                        xenoprof_log_event(current, regs, eip, mode, i);
@@ -123,18 +125,30 @@ static int ppro_check_ctrs(unsigned int const cpu,
 static void ppro_start(struct op_msrs const * const msrs)
 {
        unsigned int low,high;
-       CTRL_READ(low, high, msrs, 0);
-       CTRL_SET_ACTIVE(low);
-       CTRL_WRITE(low, high, msrs, 0);
+       int i;
+
+       for (i = 0; i < NUM_COUNTERS; ++i) {
+               if (reset_value[i]) {
+                       CTRL_READ(low, high, msrs, i);
+                       CTRL_SET_ACTIVE(low);
+                       CTRL_WRITE(low, high, msrs, i);
+               }
+       }
 }
 
 
 static void ppro_stop(struct op_msrs const * const msrs)
 {
        unsigned int low,high;
-       CTRL_READ(low, high, msrs, 0);
-       CTRL_SET_INACTIVE(low);
-       CTRL_WRITE(low, high, msrs, 0);
+       int i;
+
+       for (i = 0; i < NUM_COUNTERS; ++i) {
+               if (!reset_value[i])
+                       continue;
+               CTRL_READ(low, high, msrs, i);
+               CTRL_SET_INACTIVE(low);
+               CTRL_WRITE(low, high, msrs, i);
+       }
 }