[PATCH 3/9] oprofile, perf, x86: introduce new functions to reserve perfctrs by index

[Robert Richter <robert.richter@amd.com>]

Current perfctr reservation code allocates single pmu msrs. The msr
addresses may differ depending on the model and offset calculation is
necessary. This can be easier implemented by reserving a counter by
its index only.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
---
 arch/x86/include/asm/nmi.h             |    2 ++
 arch/x86/kernel/cpu/perfctr-watchdog.c |   29 ++++++++++++++++++++---------
 arch/x86/oprofile/op_model_amd.c       |    4 ++--
 arch/x86/oprofile/op_model_ppro.c      |    4 ++--
 4 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/arch/x86/include/asm/nmi.h b/arch/x86/include/asm/nmi.h
index 93da9c3..f5db47d 100644
--- a/arch/x86/include/asm/nmi.h
+++ b/arch/x86/include/asm/nmi.h
@@ -19,6 +19,8 @@ extern void die_nmi(char *str, struct pt_regs *regs, int do_panic);
 extern int check_nmi_watchdog(void);
 extern int nmi_watchdog_enabled;
 extern int avail_to_resrv_perfctr_nmi_bit(unsigned int);
+extern int reserve_perfctr(unsigned int);
+extern void release_perfctr(unsigned int);
 extern int reserve_perfctr_nmi(unsigned int);
 extern void release_perfctr_nmi(unsigned int);
 extern int reserve_evntsel_nmi(unsigned int);
diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c
index 5c129ee..0868b8b 100644
--- a/arch/x86/kernel/cpu/perfctr-watchdog.c
+++ b/arch/x86/kernel/cpu/perfctr-watchdog.c
@@ -117,11 +117,8 @@ int avail_to_resrv_perfctr_nmi_bit(unsigned int counter)
 }
 EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi_bit);
 
-int reserve_perfctr_nmi(unsigned int msr)
+int reserve_perfctr(unsigned int counter)
 {
-	unsigned int counter;
-
-	counter = nmi_perfctr_msr_to_bit(msr);
 	/* register not managed by the allocator? */
 	if (counter > NMI_MAX_COUNTER_BITS)
 		return 1;
@@ -130,19 +127,33 @@ int reserve_perfctr_nmi(unsigned int msr)
 		return 1;
 	return 0;
 }
-EXPORT_SYMBOL(reserve_perfctr_nmi);
+EXPORT_SYMBOL(reserve_perfctr);
 
-void release_perfctr_nmi(unsigned int msr)
+void release_perfctr(unsigned int counter)
 {
-	unsigned int counter;
-
-	counter = nmi_perfctr_msr_to_bit(msr);
 	/* register not managed by the allocator? */
 	if (counter > NMI_MAX_COUNTER_BITS)
 		return;
 
 	clear_bit(counter, perfctr_nmi_owner);
 }
+EXPORT_SYMBOL(release_perfctr);
+
+int reserve_perfctr_nmi(unsigned int msr)
+{
+	unsigned int counter;
+	counter = nmi_perfctr_msr_to_bit(msr);
+	return reserve_perfctr(counter);
+}
+EXPORT_SYMBOL(reserve_perfctr_nmi);
+
+void release_perfctr_nmi(unsigned int msr)
+{
+	unsigned int counter;
+
+	counter = nmi_perfctr_msr_to_bit(msr);
+	release_perfctr(counter);
+}
 EXPORT_SYMBOL(release_perfctr_nmi);
 
 int reserve_evntsel_nmi(unsigned int msr)
diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index 79e79a6..905995d 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -134,7 +134,7 @@ static void op_amd_fill_in_addresses(struct op_msrs * const msrs)
 	int i;
 
 	for (i = 0; i < NUM_COUNTERS; i++) {
-		if (reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i)) {
+		if (reserve_perfctr(i)) {
 			msrs->counters[i].addr = MSR_K7_PERFCTR0 + i;
 			msrs->controls[i].addr = MSR_K7_EVNTSEL0 + i;
 		}
@@ -428,7 +428,7 @@ static void op_amd_shutdown(struct op_msrs const * const msrs)
 
 	for (i = 0; i < NUM_COUNTERS; ++i) {
 		if (msrs->counters[i].addr)
-			release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
+			release_perfctr(i);
 	}
 }
 
diff --git a/arch/x86/oprofile/op_model_ppro.c b/arch/x86/oprofile/op_model_ppro.c
index d6abdf6..a838ee4 100644
--- a/arch/x86/oprofile/op_model_ppro.c
+++ b/arch/x86/oprofile/op_model_ppro.c
@@ -35,7 +35,7 @@ static void ppro_fill_in_addresses(struct op_msrs * const msrs)
 	int i;
 
 	for (i = 0; i < num_counters; i++) {
-		if (!reserve_perfctr_nmi(MSR_P6_PERFCTR0 + i)) {
+		if (reserve_perfctr(i)) {
 			msrs->counters[i].addr = MSR_P6_PERFCTR0 + i;
 			msrs->controls[i].addr = MSR_P6_EVNTSEL0 + i;
 		}
@@ -192,7 +192,7 @@ static void ppro_shutdown(struct op_msrs const * const msrs)
 
 	for (i = 0; i < num_counters; ++i) {
 		if (msrs->counters[i].addr)
-			release_perfctr_nmi(MSR_P6_PERFCTR0 + i);
+			release_perfctr(i);
 	}
 	if (reset_value) {
 		kfree(reset_value);
-- 
1.7.0