[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/op_model_athlon.c b/arch/i386/oprofile/op_model_athlon.c
index 693bdea..3057a19 100644
--- a/arch/i386/oprofile/op_model_athlon.c
+++ b/arch/i386/oprofile/op_model_athlon.c
@@ -21,10 +21,12 @@
#define NUM_COUNTERS 4
#define NUM_CONTROLS 4
+#define CTR_IS_RESERVED(msrs,c) (msrs->counters[(c)].addr ? 1 : 0)
#define CTR_READ(l,h,msrs,c) do {rdmsr(msrs->counters[(c)].addr, (l), (h));} while (0)
#define CTR_WRITE(l,msrs,c) do {wrmsr(msrs->counters[(c)].addr, -(unsigned int)(l), -1);} while (0)
#define CTR_OVERFLOWED(n) (!((n) & (1U<<31)))
+#define CTRL_IS_RESERVED(msrs,c) (msrs->controls[(c)].addr ? 1 : 0)
#define CTRL_READ(l,h,msrs,c) do {rdmsr(msrs->controls[(c)].addr, (l), (h));} while (0)
#define CTRL_WRITE(l,h,msrs,c) do {wrmsr(msrs->controls[(c)].addr, (l), (h));} while (0)
#define CTRL_SET_ACTIVE(n) (n |= (1<<22))
@@ -40,15 +42,21 @@
static void athlon_fill_in_addresses(struct op_msrs * const msrs)
{
- msrs->counters[0].addr = MSR_K7_PERFCTR0;
- msrs->counters[1].addr = MSR_K7_PERFCTR1;
- msrs->counters[2].addr = MSR_K7_PERFCTR2;
- msrs->counters[3].addr = MSR_K7_PERFCTR3;
+ int i;
- msrs->controls[0].addr = MSR_K7_EVNTSEL0;
- msrs->controls[1].addr = MSR_K7_EVNTSEL1;
- msrs->controls[2].addr = MSR_K7_EVNTSEL2;
- msrs->controls[3].addr = MSR_K7_EVNTSEL3;
+ for (i=0; i < NUM_COUNTERS; i++) {
+ if (reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i))
+ msrs->counters[i].addr = MSR_K7_PERFCTR0 + i;
+ else
+ msrs->counters[i].addr = 0;
+ }
+
+ for (i=0; i < NUM_CONTROLS; i++) {
+ if (reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i))
+ msrs->controls[i].addr = MSR_K7_EVNTSEL0 + i;
+ else
+ msrs->controls[i].addr = 0;
+ }
}
@@ -59,19 +67,23 @@
/* clear all counters */
for (i = 0 ; i < NUM_CONTROLS; ++i) {
+ if (unlikely(!CTRL_IS_RESERVED(msrs,i)))
+ continue;
CTRL_READ(low, high, msrs, i);
CTRL_CLEAR(low);
CTRL_WRITE(low, high, msrs, i);
}
-
+
/* avoid a false detection of ctr overflows in NMI handler */
for (i = 0; i < NUM_COUNTERS; ++i) {
+ if (unlikely(!CTR_IS_RESERVED(msrs,i)))
+ continue;
CTR_WRITE(1, msrs, i);
}
/* enable active counters */
for (i = 0; i < NUM_COUNTERS; ++i) {
- if (counter_config[i].enabled) {
+ if ((counter_config[i].enabled) && (CTR_IS_RESERVED(msrs,i))) {
reset_value[i] = counter_config[i].count;
CTR_WRITE(counter_config[i].count, msrs, i);
@@ -98,6 +110,8 @@
int i;
for (i = 0 ; i < NUM_COUNTERS; ++i) {
+ if (!reset_value[i])
+ continue;
CTR_READ(low, high, msrs, i);
if (CTR_OVERFLOWED(low)) {
oprofile_add_sample(regs, i);
@@ -132,12 +146,27 @@
/* Subtle: stop on all counters to avoid race with
* setting our pm callback */
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);
}
}
+static void athlon_shutdown(struct op_msrs const * const msrs)
+{
+ int i;
+
+ for (i = 0 ; i < NUM_COUNTERS ; ++i) {
+ if (CTR_IS_RESERVED(msrs,i))
+ release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
+ }
+ for (i = 0 ; i < NUM_CONTROLS ; ++i) {
+ if (CTRL_IS_RESERVED(msrs,i))
+ release_evntsel_nmi(MSR_K7_EVNTSEL0 + i);
+ }
+}
struct op_x86_model_spec const op_athlon_spec = {
.num_counters = NUM_COUNTERS,
@@ -146,5 +175,6 @@
.setup_ctrs = &athlon_setup_ctrs,
.check_ctrs = &athlon_check_ctrs,
.start = &athlon_start,
- .stop = &athlon_stop
+ .stop = &athlon_stop,
+ .shutdown = &athlon_shutdown
};