[PATCH 2/8] perf/x86/msr: Use new probe function

From: Jiri Olsa
Date: Mon Mar 18 2019 - 14:21:30 EST


Using perf_msr_probe function to add msr events.

The functionality is the same, with one exception,
that perf_msr_probe checks for rdmsr to return
value != 0 for given MSR register.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
arch/x86/events/msr.c | 76 ++++++++++++++++++++-----------------------
1 file changed, 35 insertions(+), 41 deletions(-)

diff --git a/arch/x86/events/msr.c b/arch/x86/events/msr.c
index a878e6286e4a..926d887aa606 100644
--- a/arch/x86/events/msr.c
+++ b/arch/x86/events/msr.c
@@ -2,6 +2,7 @@
#include <linux/perf_event.h>
#include <linux/nospec.h>
#include <asm/intel-family.h>
+#include "probe.h"

enum perf_msr_id {
PERF_MSR_TSC = 0,
@@ -12,32 +13,30 @@ enum perf_msr_id {
PERF_MSR_PTSC = 5,
PERF_MSR_IRPERF = 6,
PERF_MSR_THERM = 7,
- PERF_MSR_THERM_SNAP = 8,
- PERF_MSR_THERM_UNIT = 9,
PERF_MSR_EVENT_MAX,
};

-static bool test_aperfmperf(int idx)
+static bool test_aperfmperf(int idx, void *data)
{
return boot_cpu_has(X86_FEATURE_APERFMPERF);
}

-static bool test_ptsc(int idx)
+static bool test_ptsc(int idx, void *data)
{
return boot_cpu_has(X86_FEATURE_PTSC);
}

-static bool test_irperf(int idx)
+static bool test_irperf(int idx, void *data)
{
return boot_cpu_has(X86_FEATURE_IRPERF);
}

-static bool test_therm_status(int idx)
+static bool test_therm_status(int idx, void *data)
{
return boot_cpu_has(X86_FEATURE_DTHERM);
}

-static bool test_intel(int idx)
+static bool test_intel(int idx, void *data)
{
if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
boot_cpu_data.x86 != 6)
@@ -97,12 +96,6 @@ static bool test_intel(int idx)
return false;
}

-struct perf_msr {
- u64 msr;
- struct perf_pmu_events_attr *attr;
- bool (*test)(int idx);
-};
-
PMU_EVENT_ATTR_STRING(tsc, evattr_tsc, "event=0x00" );
PMU_EVENT_ATTR_STRING(aperf, evattr_aperf, "event=0x01" );
PMU_EVENT_ATTR_STRING(mperf, evattr_mperf, "event=0x02" );
@@ -114,17 +107,32 @@ PMU_EVENT_ATTR_STRING(cpu_thermal_margin, evattr_therm, "event=0x07" );
PMU_EVENT_ATTR_STRING(cpu_thermal_margin.snapshot, evattr_therm_snap, "1" );
PMU_EVENT_ATTR_STRING(cpu_thermal_margin.unit, evattr_therm_unit, "C" );

+static unsigned long msr_mask;
+
+MSR_ATTR(evattr_tsc);
+MSR_ATTR(evattr_aperf);
+MSR_ATTR(evattr_mperf);
+MSR_ATTR(evattr_pperf);
+MSR_ATTR(evattr_smi);
+MSR_ATTR(evattr_ptsc);
+MSR_ATTR(evattr_irperf);
+
+static struct attribute *msr_evattr_therm[] = {
+ &evattr_therm.attr.attr,
+ &evattr_therm_snap.attr.attr,
+ &evattr_therm_unit.attr.attr,
+ NULL,
+};
+
static struct perf_msr msr[] = {
- [PERF_MSR_TSC] = { 0, &evattr_tsc, NULL, },
- [PERF_MSR_APERF] = { MSR_IA32_APERF, &evattr_aperf, test_aperfmperf, },
- [PERF_MSR_MPERF] = { MSR_IA32_MPERF, &evattr_mperf, test_aperfmperf, },
- [PERF_MSR_PPERF] = { MSR_PPERF, &evattr_pperf, test_intel, },
- [PERF_MSR_SMI] = { MSR_SMI_COUNT, &evattr_smi, test_intel, },
- [PERF_MSR_PTSC] = { MSR_F15H_PTSC, &evattr_ptsc, test_ptsc, },
- [PERF_MSR_IRPERF] = { MSR_F17H_IRPERF, &evattr_irperf, test_irperf, },
- [PERF_MSR_THERM] = { MSR_IA32_THERM_STATUS, &evattr_therm, test_therm_status, },
- [PERF_MSR_THERM_SNAP] = { MSR_IA32_THERM_STATUS, &evattr_therm_snap, test_therm_status, },
- [PERF_MSR_THERM_UNIT] = { MSR_IA32_THERM_STATUS, &evattr_therm_unit, test_therm_status, },
+ [PERF_MSR_TSC] = { 0, msr_evattr_tsc, NULL, },
+ [PERF_MSR_APERF] = { MSR_IA32_APERF, msr_evattr_aperf, test_aperfmperf, },
+ [PERF_MSR_MPERF] = { MSR_IA32_MPERF, msr_evattr_mperf, test_aperfmperf, },
+ [PERF_MSR_PPERF] = { MSR_PPERF, msr_evattr_pperf, test_intel, },
+ [PERF_MSR_SMI] = { MSR_SMI_COUNT, msr_evattr_smi, test_intel, },
+ [PERF_MSR_PTSC] = { MSR_F15H_PTSC, msr_evattr_ptsc, test_ptsc, },
+ [PERF_MSR_IRPERF] = { MSR_F17H_IRPERF, msr_evattr_irperf, test_irperf, },
+ [PERF_MSR_THERM] = { MSR_IA32_THERM_STATUS, msr_evattr_therm, test_therm_status, },
};

static struct attribute *events_attrs[PERF_MSR_EVENT_MAX + 1] = {
@@ -168,7 +176,7 @@ static int msr_event_init(struct perf_event *event)

cfg = array_index_nospec((unsigned long)cfg, PERF_MSR_EVENT_MAX);

- if (!msr[cfg].attr)
+ if (!(msr_mask & (1 << cfg)))
return -EINVAL;

event->hw.idx = -1;
@@ -255,28 +263,14 @@ static struct pmu pmu_msr = {

static int __init msr_init(void)
{
- int i, j = 0;
-
if (!boot_cpu_has(X86_FEATURE_TSC)) {
pr_cont("no MSR PMU driver.\n");
return 0;
}

- /* Probe the MSRs. */
- for (i = PERF_MSR_TSC + 1; i < PERF_MSR_EVENT_MAX; i++) {
- u64 val;
-
- /* Virt sucks; you cannot tell if a R/O MSR is present :/ */
- if (!msr[i].test(i) || rdmsrl_safe(msr[i].msr, &val))
- msr[i].attr = NULL;
- }
-
- /* List remaining MSRs in the sysfs attrs. */
- for (i = 0; i < PERF_MSR_EVENT_MAX; i++) {
- if (msr[i].attr)
- events_attrs[j++] = &msr[i].attr->attr.attr;
- }
- events_attrs[j] = NULL;
+ msr[PERF_MSR_TSC].no_check = true;
+ msr_mask = perf_msr_probe(msr, PERF_MSR_EVENT_MAX,
+ events_attrs, NULL);

perf_pmu_register(&pmu_msr, "msr", -1);

--
2.17.2