[PATCH] i386: Utilize performance counter reservation framework in oprofile
Incorporates the new performance counter reservation system in oprofile.
Also cleans up a lot of the initialization code. The code original zero'd
out every register associated with performance counters regardless if those
registers were used or not. This causes issues with the nmi watchdog.
Now oprofile tries to reserve registers and gives up if it can't get them.
Cc: levon@movementarian.org
Cc: oprofile-list@lists.sf.net
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
diff --git a/arch/i386/oprofile/nmi_int.c b/arch/i386/oprofile/nmi_int.c
index 5f8dc8a..8710ca0 100644
--- a/arch/i386/oprofile/nmi_int.c
+++ b/arch/i386/oprofile/nmi_int.c
@@ -98,15 +98,19 @@
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 @@
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 @@
apic_write(APIC_LVTPC, saved_lvtpc[cpu]);
apic_write(APIC_LVTERR, v);
nmi_restore_registers(msrs);
+ model->shutdown(msrs);
}
@@ -284,6 +293,14 @@
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);