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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event_p4.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event_p4.c119
1 files changed, 115 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c
index ead584fb6a7d..7809d2bcb209 100644
--- a/arch/x86/kernel/cpu/perf_event_p4.c
+++ b/arch/x86/kernel/cpu/perf_event_p4.c
@@ -554,13 +554,102 @@ static __initconst const u64 p4_hw_cache_event_ids
[ C(RESULT_MISS) ] = -1,
},
},
+ [ C(NODE) ] = {
+ [ C(OP_READ) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ [ C(OP_WRITE) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ [ C(OP_PREFETCH) ] = {
+ [ C(RESULT_ACCESS) ] = -1,
+ [ C(RESULT_MISS) ] = -1,
+ },
+ },
};
+/*
+ * Because of Netburst being quite restricted in how many
+ * identical events may run simultaneously, we introduce event aliases,
+ * ie the different events which have the same functionality but
+ * utilize non-intersected resources (ESCR/CCCR/counter registers).
+ *
+ * This allow us to relax restrictions a bit and run two or more
+ * identical events together.
+ *
+ * Never set any custom internal bits such as P4_CONFIG_HT,
+ * P4_CONFIG_ALIASABLE or bits for P4_PEBS_METRIC, they are
+ * either up to date automatically or not applicable at all.
+ */
+struct p4_event_alias {
+ u64 original;
+ u64 alternative;
+} p4_event_aliases[] = {
+ {
+ /*
+ * Non-halted cycles can be substituted with non-sleeping cycles (see
+ * Intel SDM Vol3b for details). We need this alias to be able
+ * to run nmi-watchdog and 'perf top' (or any other user space tool
+ * which is interested in running PERF_COUNT_HW_CPU_CYCLES)
+ * simultaneously.
+ */
+ .original =
+ p4_config_pack_escr(P4_ESCR_EVENT(P4_EVENT_GLOBAL_POWER_EVENTS) |
+ P4_ESCR_EMASK_BIT(P4_EVENT_GLOBAL_POWER_EVENTS, RUNNING)),
+ .alternative =
+ p4_config_pack_escr(P4_ESCR_EVENT(P4_EVENT_EXECUTION_EVENT) |
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, NBOGUS0)|
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, NBOGUS1)|
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, NBOGUS2)|
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, NBOGUS3)|
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, BOGUS0) |
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, BOGUS1) |
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, BOGUS2) |
+ P4_ESCR_EMASK_BIT(P4_EVENT_EXECUTION_EVENT, BOGUS3))|
+ p4_config_pack_cccr(P4_CCCR_THRESHOLD(15) | P4_CCCR_COMPLEMENT |
+ P4_CCCR_COMPARE),
+ },
+};
+
+static u64 p4_get_alias_event(u64 config)
+{
+ u64 config_match;
+ int i;
+
+ /*
+ * Only event with special mark is allowed,
+ * we're to be sure it didn't come as malformed
+ * RAW event.
+ */
+ if (!(config & P4_CONFIG_ALIASABLE))
+ return 0;
+
+ config_match = config & P4_CONFIG_EVENT_ALIAS_MASK;
+
+ for (i = 0; i < ARRAY_SIZE(p4_event_aliases); i++) {
+ if (config_match == p4_event_aliases[i].original) {
+ config_match = p4_event_aliases[i].alternative;
+ break;
+ } else if (config_match == p4_event_aliases[i].alternative) {
+ config_match = p4_event_aliases[i].original;
+ break;
+ }
+ }
+
+ if (i >= ARRAY_SIZE(p4_event_aliases))
+ return 0;
+
+ return config_match | (config & P4_CONFIG_EVENT_ALIAS_IMMUTABLE_BITS);
+}
+
static u64 p4_general_events[PERF_COUNT_HW_MAX] = {
/* non-halted CPU clocks */
[PERF_COUNT_HW_CPU_CYCLES] =
p4_config_pack_escr(P4_ESCR_EVENT(P4_EVENT_GLOBAL_POWER_EVENTS) |
- P4_ESCR_EMASK_BIT(P4_EVENT_GLOBAL_POWER_EVENTS, RUNNING)),
+ P4_ESCR_EMASK_BIT(P4_EVENT_GLOBAL_POWER_EVENTS, RUNNING)) |
+ P4_CONFIG_ALIASABLE,
/*
* retired instructions
@@ -945,7 +1034,7 @@ static int p4_pmu_handle_irq(struct pt_regs *regs)
if (!x86_perf_event_set_period(event))
continue;
- if (perf_event_overflow(event, 1, &data, regs))
+ if (perf_event_overflow(event, &data, regs))
x86_pmu_stop(event, 0);
}
@@ -1120,6 +1209,8 @@ static int p4_pmu_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign
struct p4_event_bind *bind;
unsigned int i, thread, num;
int cntr_idx, escr_idx;
+ u64 config_alias;
+ int pass;
bitmap_zero(used_mask, X86_PMC_IDX_MAX);
bitmap_zero(escr_mask, P4_ESCR_MSR_TABLE_SIZE);
@@ -1128,6 +1219,17 @@ static int p4_pmu_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign
hwc = &cpuc->event_list[i]->hw;
thread = p4_ht_thread(cpu);
+ pass = 0;
+
+again:
+ /*
+ * It's possible to hit a circular lock
+ * between original and alternative events
+ * if both are scheduled already.
+ */
+ if (pass > 2)
+ goto done;
+
bind = p4_config_get_bind(hwc->config);
escr_idx = p4_get_escr_idx(bind->escr_msr[thread]);
if (unlikely(escr_idx == -1))
@@ -1141,8 +1243,17 @@ static int p4_pmu_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign
}
cntr_idx = p4_next_cntr(thread, used_mask, bind);
- if (cntr_idx == -1 || test_bit(escr_idx, escr_mask))
- goto done;
+ if (cntr_idx == -1 || test_bit(escr_idx, escr_mask)) {
+ /*
+ * Check whether an event alias is still available.
+ */
+ config_alias = p4_get_alias_event(hwc->config);
+ if (!config_alias)
+ goto done;
+ hwc->config = config_alias;
+ pass++;
+ goto again;
+ }
p4_pmu_swap_config_ts(hwc, cpu);
if (assign)