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Diffstat (limited to 'arch/x86/kernel/cpu/perf_counter.c')
-rw-r--r--arch/x86/kernel/cpu/perf_counter.c311
1 files changed, 277 insertions, 34 deletions
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index 76dfef23f789..900332b800f8 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -55,6 +55,7 @@ struct x86_pmu {
int num_counters_fixed;
int counter_bits;
u64 counter_mask;
+ int apic;
u64 max_period;
u64 intel_ctrl;
};
@@ -66,6 +67,52 @@ static DEFINE_PER_CPU(struct cpu_hw_counters, cpu_hw_counters) = {
};
/*
+ * Not sure about some of these
+ */
+static const u64 p6_perfmon_event_map[] =
+{
+ [PERF_COUNT_HW_CPU_CYCLES] = 0x0079,
+ [PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,
+ [PERF_COUNT_HW_CACHE_REFERENCES] = 0x0f2e,
+ [PERF_COUNT_HW_CACHE_MISSES] = 0x012e,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x00c4,
+ [PERF_COUNT_HW_BRANCH_MISSES] = 0x00c5,
+ [PERF_COUNT_HW_BUS_CYCLES] = 0x0062,
+};
+
+static u64 p6_pmu_event_map(int event)
+{
+ return p6_perfmon_event_map[event];
+}
+
+/*
+ * Counter setting that is specified not to count anything.
+ * We use this to effectively disable a counter.
+ *
+ * L2_RQSTS with 0 MESI unit mask.
+ */
+#define P6_NOP_COUNTER 0x0000002EULL
+
+static u64 p6_pmu_raw_event(u64 event)
+{
+#define P6_EVNTSEL_EVENT_MASK 0x000000FFULL
+#define P6_EVNTSEL_UNIT_MASK 0x0000FF00ULL
+#define P6_EVNTSEL_EDGE_MASK 0x00040000ULL
+#define P6_EVNTSEL_INV_MASK 0x00800000ULL
+#define P6_EVNTSEL_COUNTER_MASK 0xFF000000ULL
+
+#define P6_EVNTSEL_MASK \
+ (P6_EVNTSEL_EVENT_MASK | \
+ P6_EVNTSEL_UNIT_MASK | \
+ P6_EVNTSEL_EDGE_MASK | \
+ P6_EVNTSEL_INV_MASK | \
+ P6_EVNTSEL_COUNTER_MASK)
+
+ return event & P6_EVNTSEL_MASK;
+}
+
+
+/*
* Intel PerfMon v3. Used on Core2 and later.
*/
static const u64 intel_perfmon_event_map[] =
@@ -401,7 +448,7 @@ static const u64 amd_hw_cache_event_ids
[ C(RESULT_MISS) ] = 0x0041, /* Data Cache Misses */
},
[ C(OP_WRITE) ] = {
- [ C(RESULT_ACCESS) ] = 0x0042, /* Data Cache Refills from L2 */
+ [ C(RESULT_ACCESS) ] = 0x0142, /* Data Cache Refills :system */
[ C(RESULT_MISS) ] = 0,
},
[ C(OP_PREFETCH) ] = {
@@ -567,6 +614,7 @@ static DEFINE_MUTEX(pmc_reserve_mutex);
static bool reserve_pmc_hardware(void)
{
+#ifdef CONFIG_X86_LOCAL_APIC
int i;
if (nmi_watchdog == NMI_LOCAL_APIC)
@@ -581,9 +629,11 @@ static bool reserve_pmc_hardware(void)
if (!reserve_evntsel_nmi(x86_pmu.eventsel + i))
goto eventsel_fail;
}
+#endif
return true;
+#ifdef CONFIG_X86_LOCAL_APIC
eventsel_fail:
for (i--; i >= 0; i--)
release_evntsel_nmi(x86_pmu.eventsel + i);
@@ -598,10 +648,12 @@ perfctr_fail:
enable_lapic_nmi_watchdog();
return false;
+#endif
}
static void release_pmc_hardware(void)
{
+#ifdef CONFIG_X86_LOCAL_APIC
int i;
for (i = 0; i < x86_pmu.num_counters; i++) {
@@ -611,6 +663,7 @@ static void release_pmc_hardware(void)
if (nmi_watchdog == NMI_LOCAL_APIC)
enable_lapic_nmi_watchdog();
+#endif
}
static void hw_perf_counter_destroy(struct perf_counter *counter)
@@ -666,6 +719,7 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
{
struct perf_counter_attr *attr = &counter->attr;
struct hw_perf_counter *hwc = &counter->hw;
+ u64 config;
int err;
if (!x86_pmu_initialized())
@@ -701,6 +755,15 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
hwc->sample_period = x86_pmu.max_period;
hwc->last_period = hwc->sample_period;
atomic64_set(&hwc->period_left, hwc->sample_period);
+ } else {
+ /*
+ * If we have a PMU initialized but no APIC
+ * interrupts, we cannot sample hardware
+ * counters (user-space has to fall back and
+ * sample via a hrtimer based software counter):
+ */
+ if (!x86_pmu.apic)
+ return -EOPNOTSUPP;
}
counter->destroy = hw_perf_counter_destroy;
@@ -718,14 +781,40 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
if (attr->config >= x86_pmu.max_events)
return -EINVAL;
+
/*
* The generic map:
*/
- hwc->config |= x86_pmu.event_map(attr->config);
+ config = x86_pmu.event_map(attr->config);
+
+ if (config == 0)
+ return -ENOENT;
+
+ if (config == -1LL)
+ return -EINVAL;
+
+ hwc->config |= config;
return 0;
}
+static void p6_pmu_disable_all(void)
+{
+ struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+ u64 val;
+
+ if (!cpuc->enabled)
+ return;
+
+ cpuc->enabled = 0;
+ barrier();
+
+ /* p6 only has one enable register */
+ rdmsrl(MSR_P6_EVNTSEL0, val);
+ val &= ~ARCH_PERFMON_EVENTSEL0_ENABLE;
+ wrmsrl(MSR_P6_EVNTSEL0, val);
+}
+
static void intel_pmu_disable_all(void)
{
wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, 0);
@@ -767,6 +856,23 @@ void hw_perf_disable(void)
return x86_pmu.disable_all();
}
+static void p6_pmu_enable_all(void)
+{
+ struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+ unsigned long val;
+
+ if (cpuc->enabled)
+ return;
+
+ cpuc->enabled = 1;
+ barrier();
+
+ /* p6 only has one enable register */
+ rdmsrl(MSR_P6_EVNTSEL0, val);
+ val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
+ wrmsrl(MSR_P6_EVNTSEL0, val);
+}
+
static void intel_pmu_enable_all(void)
{
wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, x86_pmu.intel_ctrl);
@@ -784,13 +890,13 @@ static void amd_pmu_enable_all(void)
barrier();
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
+ struct perf_counter *counter = cpuc->counters[idx];
u64 val;
if (!test_bit(idx, cpuc->active_mask))
continue;
- rdmsrl(MSR_K7_EVNTSEL0 + idx, val);
- if (val & ARCH_PERFMON_EVENTSEL0_ENABLE)
- continue;
+
+ val = counter->hw.config;
val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
wrmsrl(MSR_K7_EVNTSEL0 + idx, val);
}
@@ -819,16 +925,13 @@ static inline void intel_pmu_ack_status(u64 ack)
static inline void x86_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
{
- int err;
- err = checking_wrmsrl(hwc->config_base + idx,
+ (void)checking_wrmsrl(hwc->config_base + idx,
hwc->config | ARCH_PERFMON_EVENTSEL0_ENABLE);
}
static inline void x86_pmu_disable_counter(struct hw_perf_counter *hwc, int idx)
{
- int err;
- err = checking_wrmsrl(hwc->config_base + idx,
- hwc->config);
+ (void)checking_wrmsrl(hwc->config_base + idx, hwc->config);
}
static inline void
@@ -836,13 +939,24 @@ intel_pmu_disable_fixed(struct hw_perf_counter *hwc, int __idx)
{
int idx = __idx - X86_PMC_IDX_FIXED;
u64 ctrl_val, mask;
- int err;
mask = 0xfULL << (idx * 4);
rdmsrl(hwc->config_base, ctrl_val);
ctrl_val &= ~mask;
- err = checking_wrmsrl(hwc->config_base, ctrl_val);
+ (void)checking_wrmsrl(hwc->config_base, ctrl_val);
+}
+
+static inline void
+p6_pmu_disable_counter(struct hw_perf_counter *hwc, int idx)
+{
+ struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+ u64 val = P6_NOP_COUNTER;
+
+ if (cpuc->enabled)
+ val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
+
+ (void)checking_wrmsrl(hwc->config_base + idx, val);
}
static inline void
@@ -912,6 +1026,8 @@ x86_perf_counter_set_period(struct perf_counter *counter,
err = checking_wrmsrl(hwc->counter_base + idx,
(u64)(-left) & x86_pmu.counter_mask);
+ perf_counter_update_userpage(counter);
+
return ret;
}
@@ -941,6 +1057,19 @@ intel_pmu_enable_fixed(struct hw_perf_counter *hwc, int __idx)
err = checking_wrmsrl(hwc->config_base, ctrl_val);
}
+static void p6_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
+{
+ struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+ u64 val;
+
+ val = hwc->config;
+ if (cpuc->enabled)
+ val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
+
+ (void)checking_wrmsrl(hwc->config_base + idx, val);
+}
+
+
static void intel_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
{
if (unlikely(hwc->config_base == MSR_ARCH_PERFMON_FIXED_CTR_CTRL)) {
@@ -957,8 +1086,6 @@ static void amd_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
if (cpuc->enabled)
x86_pmu_enable_counter(hwc, idx);
- else
- x86_pmu_disable_counter(hwc, idx);
}
static int
@@ -969,13 +1096,6 @@ fixed_mode_idx(struct perf_counter *counter, struct hw_perf_counter *hwc)
if (!x86_pmu.num_counters_fixed)
return -1;
- /*
- * Quirk, IA32_FIXED_CTRs do not work on current Atom processors:
- */
- if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
- boot_cpu_data.x86_model == 28)
- return -1;
-
event = hwc->config & ARCH_PERFMON_EVENT_MASK;
if (unlikely(event == x86_pmu.event_map(PERF_COUNT_HW_INSTRUCTIONS)))
@@ -1041,6 +1161,8 @@ try_generic:
x86_perf_counter_set_period(counter, hwc, idx);
x86_pmu.enable(hwc, idx);
+ perf_counter_update_userpage(counter);
+
return 0;
}
@@ -1133,6 +1255,8 @@ static void x86_pmu_disable(struct perf_counter *counter)
x86_perf_counter_update(counter, hwc, idx);
cpuc->counters[idx] = NULL;
clear_bit(idx, cpuc->used_mask);
+
+ perf_counter_update_userpage(counter);
}
/*
@@ -1177,6 +1301,49 @@ static void intel_pmu_reset(void)
local_irq_restore(flags);
}
+static int p6_pmu_handle_irq(struct pt_regs *regs)
+{
+ struct perf_sample_data data;
+ struct cpu_hw_counters *cpuc;
+ struct perf_counter *counter;
+ struct hw_perf_counter *hwc;
+ int idx, handled = 0;
+ u64 val;
+
+ data.regs = regs;
+ data.addr = 0;
+
+ cpuc = &__get_cpu_var(cpu_hw_counters);
+
+ for (idx = 0; idx < x86_pmu.num_counters; idx++) {
+ if (!test_bit(idx, cpuc->active_mask))
+ continue;
+
+ counter = cpuc->counters[idx];
+ hwc = &counter->hw;
+
+ val = x86_perf_counter_update(counter, hwc, idx);
+ if (val & (1ULL << (x86_pmu.counter_bits - 1)))
+ continue;
+
+ /*
+ * counter overflow
+ */
+ handled = 1;
+ data.period = counter->hw.last_period;
+
+ if (!x86_perf_counter_set_period(counter, hwc, idx))
+ continue;
+
+ if (perf_counter_overflow(counter, 1, &data))
+ p6_pmu_disable_counter(hwc, idx);
+ }
+
+ if (handled)
+ inc_irq_stat(apic_perf_irqs);
+
+ return handled;
+}
/*
* This handler is triggered by the local APIC, so the APIC IRQ handling
@@ -1186,14 +1353,13 @@ static int intel_pmu_handle_irq(struct pt_regs *regs)
{
struct perf_sample_data data;
struct cpu_hw_counters *cpuc;
- int bit, cpu, loops;
+ int bit, loops;
u64 ack, status;
data.regs = regs;
data.addr = 0;
- cpu = smp_processor_id();
- cpuc = &per_cpu(cpu_hw_counters, cpu);
+ cpuc = &__get_cpu_var(cpu_hw_counters);
perf_disable();
status = intel_pmu_get_status();
@@ -1250,14 +1416,13 @@ static int amd_pmu_handle_irq(struct pt_regs *regs)
struct cpu_hw_counters *cpuc;
struct perf_counter *counter;
struct hw_perf_counter *hwc;
- int cpu, idx, handled = 0;
+ int idx, handled = 0;
u64 val;
data.regs = regs;
data.addr = 0;
- cpu = smp_processor_id();
- cpuc = &per_cpu(cpu_hw_counters, cpu);
+ cpuc = &__get_cpu_var(cpu_hw_counters);
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
if (!test_bit(idx, cpuc->active_mask))
@@ -1300,18 +1465,22 @@ void smp_perf_pending_interrupt(struct pt_regs *regs)
void set_perf_counter_pending(void)
{
+#ifdef CONFIG_X86_LOCAL_APIC
apic->send_IPI_self(LOCAL_PENDING_VECTOR);
+#endif
}
void perf_counters_lapic_init(void)
{
- if (!x86_pmu_initialized())
+#ifdef CONFIG_X86_LOCAL_APIC
+ if (!x86_pmu.apic || !x86_pmu_initialized())
return;
/*
* Always use NMI for PMU
*/
apic_write(APIC_LVTPC, APIC_DM_NMI);
+#endif
}
static int __kprobes
@@ -1335,7 +1504,9 @@ perf_counter_nmi_handler(struct notifier_block *self,
regs = args->regs;
+#ifdef CONFIG_X86_LOCAL_APIC
apic_write(APIC_LVTPC, APIC_DM_NMI);
+#endif
/*
* Can't rely on the handled return value to say it was our NMI, two
* counters could trigger 'simultaneously' raising two back-to-back NMIs.
@@ -1354,6 +1525,33 @@ static __read_mostly struct notifier_block perf_counter_nmi_notifier = {
.priority = 1
};
+static struct x86_pmu p6_pmu = {
+ .name = "p6",
+ .handle_irq = p6_pmu_handle_irq,
+ .disable_all = p6_pmu_disable_all,
+ .enable_all = p6_pmu_enable_all,
+ .enable = p6_pmu_enable_counter,
+ .disable = p6_pmu_disable_counter,
+ .eventsel = MSR_P6_EVNTSEL0,
+ .perfctr = MSR_P6_PERFCTR0,
+ .event_map = p6_pmu_event_map,
+ .raw_event = p6_pmu_raw_event,
+ .max_events = ARRAY_SIZE(p6_perfmon_event_map),
+ .apic = 1,
+ .max_period = (1ULL << 31) - 1,
+ .version = 0,
+ .num_counters = 2,
+ /*
+ * Counters have 40 bits implemented. However they are designed such
+ * that bits [32-39] are sign extensions of bit 31. As such the
+ * effective width of a counter for P6-like PMU is 32 bits only.
+ *
+ * See IA-32 Intel Architecture Software developer manual Vol 3B
+ */
+ .counter_bits = 32,
+ .counter_mask = (1ULL << 32) - 1,
+};
+
static struct x86_pmu intel_pmu = {
.name = "Intel",
.handle_irq = intel_pmu_handle_irq,
@@ -1366,6 +1564,7 @@ static struct x86_pmu intel_pmu = {
.event_map = intel_pmu_event_map,
.raw_event = intel_pmu_raw_event,
.max_events = ARRAY_SIZE(intel_perfmon_event_map),
+ .apic = 1,
/*
* Intel PMCs cannot be accessed sanely above 32 bit width,
* so we install an artificial 1<<31 period regardless of
@@ -1389,10 +1588,43 @@ static struct x86_pmu amd_pmu = {
.num_counters = 4,
.counter_bits = 48,
.counter_mask = (1ULL << 48) - 1,
+ .apic = 1,
/* use highest bit to detect overflow */
.max_period = (1ULL << 47) - 1,
};
+static int p6_pmu_init(void)
+{
+ switch (boot_cpu_data.x86_model) {
+ case 1:
+ case 3: /* Pentium Pro */
+ case 5:
+ case 6: /* Pentium II */
+ case 7:
+ case 8:
+ case 11: /* Pentium III */
+ break;
+ case 9:
+ case 13:
+ /* Pentium M */
+ break;
+ default:
+ pr_cont("unsupported p6 CPU model %d ",
+ boot_cpu_data.x86_model);
+ return -ENODEV;
+ }
+
+ x86_pmu = p6_pmu;
+
+ if (!cpu_has_apic) {
+ pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n");
+ pr_info("no hardware sampling interrupt available.\n");
+ x86_pmu.apic = 0;
+ }
+
+ return 0;
+}
+
static int intel_pmu_init(void)
{
union cpuid10_edx edx;
@@ -1401,8 +1633,14 @@ static int intel_pmu_init(void)
unsigned int ebx;
int version;
- if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
+ if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {
+ /* check for P6 processor family */
+ if (boot_cpu_data.x86 == 6) {
+ return p6_pmu_init();
+ } else {
return -ENODEV;
+ }
+ }
/*
* Check whether the Architectural PerfMon supports
@@ -1428,8 +1666,6 @@ static int intel_pmu_init(void)
*/
x86_pmu.num_counters_fixed = max((int)edx.split.num_counters_fixed, 3);
- rdmsrl(MSR_CORE_PERF_GLOBAL_CTRL, x86_pmu.intel_ctrl);
-
/*
* Install the hw-cache-events table:
*/
@@ -1499,21 +1735,22 @@ void __init init_hw_perf_counters(void)
pr_cont("%s PMU driver.\n", x86_pmu.name);
if (x86_pmu.num_counters > X86_PMC_MAX_GENERIC) {
- x86_pmu.num_counters = X86_PMC_MAX_GENERIC;
WARN(1, KERN_ERR "hw perf counters %d > max(%d), clipping!",
x86_pmu.num_counters, X86_PMC_MAX_GENERIC);
+ x86_pmu.num_counters = X86_PMC_MAX_GENERIC;
}
perf_counter_mask = (1 << x86_pmu.num_counters) - 1;
perf_max_counters = x86_pmu.num_counters;
if (x86_pmu.num_counters_fixed > X86_PMC_MAX_FIXED) {
- x86_pmu.num_counters_fixed = X86_PMC_MAX_FIXED;
WARN(1, KERN_ERR "hw perf counters fixed %d > max(%d), clipping!",
x86_pmu.num_counters_fixed, X86_PMC_MAX_FIXED);
+ x86_pmu.num_counters_fixed = X86_PMC_MAX_FIXED;
}
perf_counter_mask |=
((1LL << x86_pmu.num_counters_fixed)-1) << X86_PMC_IDX_FIXED;
+ x86_pmu.intel_ctrl = perf_counter_mask;
perf_counters_lapic_init();
register_die_notifier(&perf_counter_nmi_notifier);
@@ -1563,6 +1800,7 @@ void callchain_store(struct perf_callchain_entry *entry, u64 ip)
static DEFINE_PER_CPU(struct perf_callchain_entry, irq_entry);
static DEFINE_PER_CPU(struct perf_callchain_entry, nmi_entry);
+static DEFINE_PER_CPU(int, in_nmi_frame);
static void
@@ -1578,7 +1816,9 @@ static void backtrace_warning(void *data, char *msg)
static int backtrace_stack(void *data, char *name)
{
- /* Process all stacks: */
+ per_cpu(in_nmi_frame, smp_processor_id()) =
+ x86_is_stack_id(NMI_STACK, name);
+
return 0;
}
@@ -1586,6 +1826,9 @@ static void backtrace_address(void *data, unsigned long addr, int reliable)
{
struct perf_callchain_entry *entry = data;
+ if (per_cpu(in_nmi_frame, smp_processor_id()))
+ return;
+
if (reliable)
callchain_store(entry, addr);
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.