[PATCH] i386: Utilize performance counter reservation framework in oprofile

[linux-2.6] / arch / i386 / oprofile / nmi_int.c

diff --git a/arch/i386/oprofile/nmi_int.c b/arch/i386/oprofile/nmi_int.c
index 5f8dc8a21bd7157e2fa9e40a6b18422fc0ed2c00..8710ca081b1e43e01ef340f954ad4160934274d3 100644 (file)
--- a/arch/i386/oprofile/nmi_int.c
+++ b/arch/i386/oprofile/nmi_int.c
@@ -98,15 +98,19 @@ static void nmi_cpu_save_registers(struct op_msrs * msrs)
        unsigned int i;
 
        for (i = 0; i < nr_ctrs; ++i) {
-               rdmsr(counters[i].addr,
-                       counters[i].saved.low,
-                       counters[i].saved.high);
+               if (counters[i].addr){
+                       rdmsr(counters[i].addr,
+                               counters[i].saved.low,
+                               counters[i].saved.high);
+               }
        }
  
        for (i = 0; i < nr_ctrls; ++i) {
-               rdmsr(controls[i].addr,
-                       controls[i].saved.low,
-                       controls[i].saved.high);
+               if (controls[i].addr){
+                       rdmsr(controls[i].addr,
+                               controls[i].saved.low,
+                               controls[i].saved.high);
+               }
        }
 }
 
@@ -205,15 +209,19 @@ static void nmi_restore_registers(struct op_msrs * msrs)
        unsigned int i;
 
        for (i = 0; i < nr_ctrls; ++i) {
-               wrmsr(controls[i].addr,
-                       controls[i].saved.low,
-                       controls[i].saved.high);
+               if (controls[i].addr){
+                       wrmsr(controls[i].addr,
+                               controls[i].saved.low,
+                               controls[i].saved.high);
+               }
        }
  
        for (i = 0; i < nr_ctrs; ++i) {
-               wrmsr(counters[i].addr,
-                       counters[i].saved.low,
-                       counters[i].saved.high);
+               if (counters[i].addr){
+                       wrmsr(counters[i].addr,
+                               counters[i].saved.low,
+                               counters[i].saved.high);
+               }
        }
 }
  
@@ -234,6 +242,7 @@ static void nmi_cpu_shutdown(void * dummy)
        apic_write(APIC_LVTPC, saved_lvtpc[cpu]);
        apic_write(APIC_LVTERR, v);
        nmi_restore_registers(msrs);
+       model->shutdown(msrs);
 }
 
  
@@ -284,6 +293,14 @@ static int nmi_create_files(struct super_block * sb, struct dentry * root)
                struct dentry * dir;
                char buf[4];
  
+               /* quick little hack to _not_ expose a counter if it is not
+                * available for use.  This should protect userspace app.
+                * NOTE:  assumes 1:1 mapping here (that counters are organized
+                *        sequentially in their struct assignment).
+                */
+               if (unlikely(!avail_to_resrv_perfctr_nmi_bit(i)))
+                       continue;
+
                snprintf(buf,  sizeof(buf), "%d", i);
                dir = oprofilefs_mkdir(sb, root, buf);
                oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled);