1 files changed, 416 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_amd.c b/arch/x86/kernel/cpu/perf_event_amd.c
new file mode 100644
index 000000000000..8f3dbfda3c4f
--- /dev/null
+++ b/arch/x86/kernel/cpu/perf_event_amd.c
@@ -0,0 +1,416 @@
+#ifdef CONFIG_CPU_SUP_AMD
+
+static DEFINE_RAW_SPINLOCK(amd_nb_lock);
+
+static __initconst u64 amd_hw_cache_event_ids
+                                [PERF_COUNT_HW_CACHE_MAX]
+                                [PERF_COUNT_HW_CACHE_OP_MAX]
+                                [PERF_COUNT_HW_CACHE_RESULT_MAX] =
+{
+ [ C(L1D) ] = {
+        [ C(OP_READ) ] = {
+                [ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses        */
+                [ C(RESULT_MISS)   ] = 0x0041, /* Data Cache Misses          */
+        },
+        [ C(OP_WRITE) ] = {
+                [ C(RESULT_ACCESS) ] = 0x0142, /* Data Cache Refills :system */
+                [ C(RESULT_MISS)   ] = 0,
+        },
+        [ C(OP_PREFETCH) ] = {
+                [ C(RESULT_ACCESS) ] = 0x0267, /* Data Prefetcher :attempts  */
+                [ C(RESULT_MISS)   ] = 0x0167, /* Data Prefetcher :cancelled */
+        },
+ },
+ [ C(L1I ) ] = {
+        [ C(OP_READ) ] = {
+                [ C(RESULT_ACCESS) ] = 0x0080, /* Instruction cache fetches  */
+                [ C(RESULT_MISS)   ] = 0x0081, /* Instruction cache misses   */
+        },
+        [ C(OP_WRITE) ] = {
+                [ C(RESULT_ACCESS) ] = -1,
+                [ C(RESULT_MISS)   ] = -1,
+        },
+        [ C(OP_PREFETCH) ] = {
+                [ C(RESULT_ACCESS) ] = 0x014B, /* Prefetch Instructions :Load */
+                [ C(RESULT_MISS)   ] = 0,
+        },
+ },
+ [ C(LL  ) ] = {
+        [ C(OP_READ) ] = {
+                [ C(RESULT_ACCESS) ] = 0x037D, /* Requests to L2 Cache :IC+DC */
+                [ C(RESULT_MISS)   ] = 0x037E, /* L2 Cache Misses : IC+DC     */
+        },
+        [ C(OP_WRITE) ] = {
+                [ C(RESULT_ACCESS) ] = 0x017F, /* L2 Fill/Writeback           */
+                [ C(RESULT_MISS)   ] = 0,
+        },
+        [ C(OP_PREFETCH) ] = {
+                [ C(RESULT_ACCESS) ] = 0,
+                [ C(RESULT_MISS)   ] = 0,
+        },
+ },
+ [ C(DTLB) ] = {
+        [ C(OP_READ) ] = {
+                [ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses        */
+                [ C(RESULT_MISS)   ] = 0x0046, /* L1 DTLB and L2 DLTB Miss   */
+        },
+        [ C(OP_WRITE) ] = {
+                [ C(RESULT_ACCESS) ] = 0,
+                [ C(RESULT_MISS)   ] = 0,
+        },
+        [ C(OP_PREFETCH) ] = {
+                [ C(RESULT_ACCESS) ] = 0,
+                [ C(RESULT_MISS)   ] = 0,
+        },
+ },
+ [ C(ITLB) ] = {
+        [ C(OP_READ) ] = {
+                [ C(RESULT_ACCESS) ] = 0x0080, /* Instruction fecthes        */
+                [ C(RESULT_MISS)   ] = 0x0085, /* Instr. fetch ITLB misses   */
+        },
+        [ C(OP_WRITE) ] = {
+                [ C(RESULT_ACCESS) ] = -1,
+                [ C(RESULT_MISS)   ] = -1,
+        },
+        [ C(OP_PREFETCH) ] = {
+                [ C(RESULT_ACCESS) ] = -1,
+                [ C(RESULT_MISS)   ] = -1,
+        },
+ },
+ [ C(BPU ) ] = {
+        [ C(OP_READ) ] = {
+                [ C(RESULT_ACCESS) ] = 0x00c2, /* Retired Branch Instr.      */
+                [ C(RESULT_MISS)   ] = 0x00c3, /* Retired Mispredicted BI    */
+        },
+        [ C(OP_WRITE) ] = {
+                [ C(RESULT_ACCESS) ] = -1,
+                [ C(RESULT_MISS)   ] = -1,
+        },
+        [ C(OP_PREFETCH) ] = {
+                [ C(RESULT_ACCESS) ] = -1,
+                [ C(RESULT_MISS)   ] = -1,
+        },
+ },
+};
+
+/*
+ * AMD Performance Monitor K7 and later.
+ */
+static const u64 amd_perfmon_event_map[] =
+{
+  [PERF_COUNT_HW_CPU_CYCLES]            = 0x0076,
+  [PERF_COUNT_HW_INSTRUCTIONS]          = 0x00c0,
+  [PERF_COUNT_HW_CACHE_REFERENCES]      = 0x0080,
+  [PERF_COUNT_HW_CACHE_MISSES]          = 0x0081,
+  [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]   = 0x00c4,
+  [PERF_COUNT_HW_BRANCH_MISSES]         = 0x00c5,
+};
+
+static u64 amd_pmu_event_map(int hw_event)
+{
+        return amd_perfmon_event_map[hw_event];
+}
+
+static u64 amd_pmu_raw_event(u64 hw_event)
+{
+#define K7_EVNTSEL_EVENT_MASK   0xF000000FFULL
+#define K7_EVNTSEL_UNIT_MASK    0x00000FF00ULL
+#define K7_EVNTSEL_EDGE_MASK    0x000040000ULL
+#define K7_EVNTSEL_INV_MASK     0x000800000ULL
+#define K7_EVNTSEL_REG_MASK     0x0FF000000ULL
+
+#define K7_EVNTSEL_MASK                 \
+        (K7_EVNTSEL_EVENT_MASK |        \
+         K7_EVNTSEL_UNIT_MASK  |        \
+         K7_EVNTSEL_EDGE_MASK  |        \
+         K7_EVNTSEL_INV_MASK   |        \
+         K7_EVNTSEL_REG_MASK)
+
+        return hw_event & K7_EVNTSEL_MASK;
+}
+
+/*
+ * AMD64 events are detected based on their event codes.
+ */
+static inline int amd_is_nb_event(struct hw_perf_event *hwc)
+{
+        return (hwc->config & 0xe0) == 0xe0;
+}
+
+static void amd_put_event_constraints(struct cpu_hw_events *cpuc,
+                                      struct perf_event *event)
+{
+        struct hw_perf_event *hwc = &event->hw;
+        struct amd_nb *nb = cpuc->amd_nb;
+        int i;
+
+        /*
+         * only care about NB events
+         */
+        if (!(nb && amd_is_nb_event(hwc)))
+                return;
+
+        /*
+         * need to scan whole list because event may not have
+         * been assigned during scheduling
+         *
+         * no race condition possible because event can only
+         * be removed on one CPU at a time AND PMU is disabled
+         * when we come here
+         */
+        for (i = 0; i < x86_pmu.num_events; i++) {
+                if (nb->owners[i] == event) {
+                        cmpxchg(nb->owners+i, event, NULL);
+                        break;
+                }
+        }
+}
+
+ /*
+  * AMD64 NorthBridge events need special treatment because
+  * counter access needs to be synchronized across all cores
+  * of a package. Refer to BKDG section 3.12
+  *
+  * NB events are events measuring L3 cache, Hypertransport
+  * traffic. They are identified by an event code >= 0xe00.
+  * They measure events on the NorthBride which is shared
+  * by all cores on a package. NB events are counted on a
+  * shared set of counters. When a NB event is programmed
+  * in a counter, the data actually comes from a shared
+  * counter. Thus, access to those counters needs to be
+  * synchronized.
+  *
+  * We implement the synchronization such that no two cores
+  * can be measuring NB events using the same counters. Thus,
+  * we maintain a per-NB allocation table. The available slot
+  * is propagated using the event_constraint structure.
+  *
+  * We provide only one choice for each NB event based on
+  * the fact that only NB events have restrictions. Consequently,
+  * if a counter is available, there is a guarantee the NB event
+  * will be assigned to it. If no slot is available, an empty
+  * constraint is returned and scheduling will eventually fail
+  * for this event.
+  *
+  * Note that all cores attached the same NB compete for the same
+  * counters to host NB events, this is why we use atomic ops. Some
+  * multi-chip CPUs may have more than one NB.
+  *
+  * Given that resources are allocated (cmpxchg), they must be
+  * eventually freed for others to use. This is accomplished by
+  * calling amd_put_event_constraints().
+  *
+  * Non NB events are not impacted by this restriction.
+  */
+static struct event_constraint *
+amd_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
+{
+        struct hw_perf_event *hwc = &event->hw;
+        struct amd_nb *nb = cpuc->amd_nb;
+        struct perf_event *old = NULL;
+        int max = x86_pmu.num_events;
+        int i, j, k = -1;
+
+        /*
+         * if not NB event or no NB, then no constraints
+         */
+        if (!(nb && amd_is_nb_event(hwc)))
+                return &unconstrained;
+
+        /*
+         * detect if already present, if so reuse
+         *
+         * cannot merge with actual allocation
+         * because of possible holes
+         *
+         * event can already be present yet not assigned (in hwc->idx)
+         * because of successive calls to x86_schedule_events() from
+         * hw_perf_group_sched_in() without hw_perf_enable()
+         */
+        for (i = 0; i < max; i++) {
+                /*
+                 * keep track of first free slot
+                 */
+                if (k == -1 && !nb->owners[i])
+                        k = i;
+
+                /* already present, reuse */
+                if (nb->owners[i] == event)
+                        goto done;
+        }
+        /*
+         * not present, so grab a new slot
+         * starting either at:
+         */
+        if (hwc->idx != -1) {
+                /* previous assignment */
+                i = hwc->idx;
+        } else if (k != -1) {
+                /* start from free slot found */
+                i = k;
+        } else {
+                /*
+                 * event not found, no slot found in
+                 * first pass, try again from the
+                 * beginning
+                 */
+                i = 0;
+        }
+        j = i;
+        do {
+                old = cmpxchg(nb->owners+i, NULL, event);
+                if (!old)
+                        break;
+                if (++i == max)
+                        i = 0;
+        } while (i != j);
+done:
+        if (!old)
+                return &nb->event_constraints[i];
+
+        return &emptyconstraint;
+}
+
+static __initconst struct x86_pmu amd_pmu = {
+        .name                   = "AMD",
+        .handle_irq             = x86_pmu_handle_irq,
+        .disable_all            = x86_pmu_disable_all,
+        .enable_all             = x86_pmu_enable_all,
+        .enable                 = x86_pmu_enable_event,
+        .disable                = x86_pmu_disable_event,
+        .eventsel               = MSR_K7_EVNTSEL0,
+        .perfctr                = MSR_K7_PERFCTR0,
+        .event_map              = amd_pmu_event_map,
+        .raw_event              = amd_pmu_raw_event,
+        .max_events             = ARRAY_SIZE(amd_perfmon_event_map),
+        .num_events             = 4,
+        .event_bits             = 48,
+        .event_mask             = (1ULL << 48) - 1,
+        .apic                   = 1,
+        /* use highest bit to detect overflow */
+        .max_period             = (1ULL << 47) - 1,
+        .get_event_constraints  = amd_get_event_constraints,
+        .put_event_constraints  = amd_put_event_constraints
+};
+
+static struct amd_nb *amd_alloc_nb(int cpu, int nb_id)
+{
+        struct amd_nb *nb;
+        int i;
+
+        nb = kmalloc(sizeof(struct amd_nb), GFP_KERNEL);
+        if (!nb)
+                return NULL;
+
+        memset(nb, 0, sizeof(*nb));
+        nb->nb_id = nb_id;
+
+        /*
+         * initialize all possible NB constraints
+         */
+        for (i = 0; i < x86_pmu.num_events; i++) {
+                set_bit(i, nb->event_constraints[i].idxmsk);
+                nb->event_constraints[i].weight = 1;
+        }
+        return nb;
+}
+
+static void amd_pmu_cpu_online(int cpu)
+{
+        struct cpu_hw_events *cpu1, *cpu2;
+        struct amd_nb *nb = NULL;
+        int i, nb_id;
+
+        if (boot_cpu_data.x86_max_cores < 2)
+                return;
+
+        /*
+         * function may be called too early in the
+         * boot process, in which case nb_id is bogus
+         */
+        nb_id = amd_get_nb_id(cpu);
+        if (nb_id == BAD_APICID)
+                return;
+
+        cpu1 = &per_cpu(cpu_hw_events, cpu);
+        cpu1->amd_nb = NULL;
+
+        raw_spin_lock(&amd_nb_lock);
+
+        for_each_online_cpu(i) {
+                cpu2 = &per_cpu(cpu_hw_events, i);
+                nb = cpu2->amd_nb;
+                if (!nb)
+                        continue;
+                if (nb->nb_id == nb_id)
+                        goto found;
+        }
+
+        nb = amd_alloc_nb(cpu, nb_id);
+        if (!nb) {
+                pr_err("perf_events: failed NB allocation for CPU%d\n", cpu);
+                raw_spin_unlock(&amd_nb_lock);
+                return;
+        }
+found:
+        nb->refcnt++;
+        cpu1->amd_nb = nb;
+
+        raw_spin_unlock(&amd_nb_lock);
+}
+
+static void amd_pmu_cpu_offline(int cpu)
+{
+        struct cpu_hw_events *cpuhw;
+
+        if (boot_cpu_data.x86_max_cores < 2)
+                return;
+
+        cpuhw = &per_cpu(cpu_hw_events, cpu);
+
+        raw_spin_lock(&amd_nb_lock);
+
+        if (--cpuhw->amd_nb->refcnt == 0)
+                kfree(cpuhw->amd_nb);
+
+        cpuhw->amd_nb = NULL;
+
+        raw_spin_unlock(&amd_nb_lock);
+}
+
+static __init int amd_pmu_init(void)
+{
+        /* Performance-monitoring supported from K7 and later: */
+        if (boot_cpu_data.x86 < 6)
+                return -ENODEV;
+
+        x86_pmu = amd_pmu;
+
+        /* Events are common for all AMDs */
+        memcpy(hw_cache_event_ids, amd_hw_cache_event_ids,
+               sizeof(hw_cache_event_ids));
+
+        /*
+         * explicitly initialize the boot cpu, other cpus will get
+         * the cpu hotplug callbacks from smp_init()
+         */
+        amd_pmu_cpu_online(smp_processor_id());
+        return 0;
+}
+
+#else /* CONFIG_CPU_SUP_AMD */
+
+static int amd_pmu_init(void)
+{
+        return 0;
+}
+
+static void amd_pmu_cpu_online(int cpu)
+{
+}
+
+static void amd_pmu_cpu_offline(int cpu)
+{
+}
+
+#endif