diff options
Diffstat (limited to 'arch/x86/kernel/cpu/perf_event_p4.c')
-rw-r--r-- | arch/x86/kernel/cpu/perf_event_p4.c | 135 |
1 files changed, 106 insertions, 29 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c index fb901c5080f7..8b7a0c306784 100644 --- a/arch/x86/kernel/cpu/perf_event_p4.c +++ b/arch/x86/kernel/cpu/perf_event_p4.c @@ -570,11 +570,92 @@ static __initconst const u64 p4_hw_cache_event_ids }, }; +/* + * Because of Netburst being quite restricted in now + * many same events can run simultaneously, we use + * event aliases, ie different events which have the + * same functionallity but use non-intersected resources + * (ESCR/CCCR/couter registers). This allow us to run + * two or more semi-same events together. It is done + * transparently to a user space. + * + * Never set any cusom internal bits such as P4_CONFIG_HT, + * P4_CONFIG_ALIASABLE or bits for P4_PEBS_METRIC, they are + * either up-to-dated automatically either not appliable + * at all. + * + * And be really carefull choosing aliases! + */ +struct p4_event_alias { + u64 orig; + u64 alter; +} p4_event_aliases[] = { + { + /* + * Non-halted cycles can be substituted with + * non-sleeping cycles (see Intel SDM Vol3b for + * details). + */ + .orig = + p4_config_pack_escr(P4_ESCR_EVENT(P4_EVENT_GLOBAL_POWER_EVENTS) | + P4_ESCR_EMASK_BIT(P4_EVENT_GLOBAL_POWER_EVENTS, RUNNING)), + .alter = + 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; + + /* + * Probably we're lucky and don't have to do + * matching over all config bits. + */ + if (!(config & P4_CONFIG_ALIASABLE)) + return 0; + + config_match = config & P4_CONFIG_EVENT_ALIAS_MASK; + + /* + * If an event was previously swapped to the alter config + * we should swap it back otherwise contnention on registers + * will return back. + */ + for (i = 0; i < ARRAY_SIZE(p4_event_aliases); i++) { + if (config_match == p4_event_aliases[i].orig) { + config_match = p4_event_aliases[i].alter; + break; + } else if (config_match == p4_event_aliases[i].alter) { + config_match = p4_event_aliases[i].orig; + 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 @@ -719,31 +800,6 @@ static int p4_validate_raw_event(struct perf_event *event) return 0; } -static void p4_hw_watchdog_set_attr(struct perf_event_attr *wd_attr) -{ - /* - * Watchdog ticks are special on Netburst, we use - * that named "non-sleeping" ticks as recommended - * by Intel SDM Vol3b. - */ - WARN_ON_ONCE(wd_attr->type != PERF_TYPE_HARDWARE || - wd_attr->config != PERF_COUNT_HW_CPU_CYCLES); - - wd_attr->type = PERF_TYPE_RAW; - wd_attr->config = - 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 int p4_hw_config(struct perf_event *event) { int cpu = get_cpu(); @@ -1159,6 +1215,8 @@ 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); @@ -1167,6 +1225,17 @@ 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: + /* + * Aliases are swappable so we may hit circular + * lock if both original config and alias need + * resources (MSR registers) which already busy. + */ + 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)) @@ -1180,8 +1249,17 @@ 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)) { + /* + * Probably 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) @@ -1218,7 +1296,6 @@ static __initconst const struct x86_pmu p4_pmu = { .cntval_bits = ARCH_P4_CNTRVAL_BITS, .cntval_mask = ARCH_P4_CNTRVAL_MASK, .max_period = (1ULL << (ARCH_P4_CNTRVAL_BITS - 1)) - 1, - .hw_watchdog_set_attr = p4_hw_watchdog_set_attr, .hw_config = p4_hw_config, .schedule_events = p4_pmu_schedule_events, /* |