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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event.h')
-rw-r--r--arch/x86/kernel/cpu/perf_event.h51
1 files changed, 48 insertions, 3 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h
index b9698d40ac4b..8944062f46e2 100644
--- a/arch/x86/kernel/cpu/perf_event.h
+++ b/arch/x86/kernel/cpu/perf_event.h
@@ -45,6 +45,7 @@ struct event_constraint {
u64 code;
u64 cmask;
int weight;
+ int overlap;
};
struct amd_nb {
@@ -151,15 +152,40 @@ struct cpu_hw_events {
void *kfree_on_online;
};
-#define __EVENT_CONSTRAINT(c, n, m, w) {\
+#define __EVENT_CONSTRAINT(c, n, m, w, o) {\
{ .idxmsk64 = (n) }, \
.code = (c), \
.cmask = (m), \
.weight = (w), \
+ .overlap = (o), \
}
#define EVENT_CONSTRAINT(c, n, m) \
- __EVENT_CONSTRAINT(c, n, m, HWEIGHT(n))
+ __EVENT_CONSTRAINT(c, n, m, HWEIGHT(n), 0)
+
+/*
+ * The overlap flag marks event constraints with overlapping counter
+ * masks. This is the case if the counter mask of such an event is not
+ * a subset of any other counter mask of a constraint with an equal or
+ * higher weight, e.g.:
+ *
+ * c_overlaps = EVENT_CONSTRAINT_OVERLAP(0, 0x09, 0);
+ * c_another1 = EVENT_CONSTRAINT(0, 0x07, 0);
+ * c_another2 = EVENT_CONSTRAINT(0, 0x38, 0);
+ *
+ * The event scheduler may not select the correct counter in the first
+ * cycle because it needs to know which subsequent events will be
+ * scheduled. It may fail to schedule the events then. So we set the
+ * overlap flag for such constraints to give the scheduler a hint which
+ * events to select for counter rescheduling.
+ *
+ * Care must be taken as the rescheduling algorithm is O(n!) which
+ * will increase scheduling cycles for an over-commited system
+ * dramatically. The number of such EVENT_CONSTRAINT_OVERLAP() macros
+ * and its counter masks must be kept at a minimum.
+ */
+#define EVENT_CONSTRAINT_OVERLAP(c, n, m) \
+ __EVENT_CONSTRAINT(c, n, m, HWEIGHT(n), 1)
/*
* Constraint on the Event code.
@@ -235,6 +261,11 @@ union perf_capabilities {
u64 capabilities;
};
+struct x86_pmu_quirk {
+ struct x86_pmu_quirk *next;
+ void (*func)(void);
+};
+
/*
* struct x86_pmu - generic x86 pmu
*/
@@ -259,6 +290,11 @@ struct x86_pmu {
int num_counters_fixed;
int cntval_bits;
u64 cntval_mask;
+ union {
+ unsigned long events_maskl;
+ unsigned long events_mask[BITS_TO_LONGS(ARCH_PERFMON_EVENTS_COUNT)];
+ };
+ int events_mask_len;
int apic;
u64 max_period;
struct event_constraint *
@@ -268,7 +304,7 @@ struct x86_pmu {
void (*put_event_constraints)(struct cpu_hw_events *cpuc,
struct perf_event *event);
struct event_constraint *event_constraints;
- void (*quirks)(void);
+ struct x86_pmu_quirk *quirks;
int perfctr_second_write;
int (*cpu_prepare)(int cpu);
@@ -309,6 +345,15 @@ struct x86_pmu {
struct perf_guest_switch_msr *(*guest_get_msrs)(int *nr);
};
+#define x86_add_quirk(func_) \
+do { \
+ static struct x86_pmu_quirk __quirk __initdata = { \
+ .func = func_, \
+ }; \
+ __quirk.next = x86_pmu.quirks; \
+ x86_pmu.quirks = &__quirk; \
+} while (0)
+
#define ERF_NO_HT_SHARING 1
#define ERF_HAS_RSP_1 2