[PATCH 35/49] perf parse-events: Create two hybrid hardware events

From: kan . liang
Date: Mon Feb 08 2021 - 13:13:49 EST


From: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>

For hardware events, they have pre-defined configs. The kernel
needs to know where the event comes from (e.g. from cpu_core pmu
or from cpu_atom pmu). But the perf type 'PERF_TYPE_HARDWARE'
can't carry pmu information.

So the kernel introduces a new type 'PERF_TYPE_HARDWARE_PMU'.
The new attr.config layout for PERF_TYPE_HARDWARE_PMU is:

0xDD000000AA
AA: original hardware event ID
DD: PMU type ID

PMU type ID is retrieved from sysfs. For example,

cat /sys/devices/cpu_atom/type
10

cat /sys/devices/cpu_core/type
4

When enabling a hybrid hardware event without specified pmu, such as,
'perf stat -e cycles -a', two events are created automatically. One
is for atom, the other is for core.

root@otcpl-adl-s-2:~# ./perf stat -e cycles -vv -a -- sleep 1
Control descriptor is not initialized
------------------------------------------------------------
perf_event_attr:
type 6
size 120
config 0x400000000
sample_type IDENTIFIER
read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
disabled 1
inherit 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 3
sys_perf_event_open: pid -1 cpu 1 group_fd -1 flags 0x8 = 4
sys_perf_event_open: pid -1 cpu 2 group_fd -1 flags 0x8 = 5
sys_perf_event_open: pid -1 cpu 3 group_fd -1 flags 0x8 = 7
sys_perf_event_open: pid -1 cpu 4 group_fd -1 flags 0x8 = 8
sys_perf_event_open: pid -1 cpu 5 group_fd -1 flags 0x8 = 9
sys_perf_event_open: pid -1 cpu 6 group_fd -1 flags 0x8 = 10
sys_perf_event_open: pid -1 cpu 7 group_fd -1 flags 0x8 = 11
sys_perf_event_open: pid -1 cpu 8 group_fd -1 flags 0x8 = 12
sys_perf_event_open: pid -1 cpu 9 group_fd -1 flags 0x8 = 13
sys_perf_event_open: pid -1 cpu 10 group_fd -1 flags 0x8 = 14
sys_perf_event_open: pid -1 cpu 11 group_fd -1 flags 0x8 = 15
sys_perf_event_open: pid -1 cpu 12 group_fd -1 flags 0x8 = 16
sys_perf_event_open: pid -1 cpu 13 group_fd -1 flags 0x8 = 17
sys_perf_event_open: pid -1 cpu 14 group_fd -1 flags 0x8 = 18
sys_perf_event_open: pid -1 cpu 15 group_fd -1 flags 0x8 = 19
------------------------------------------------------------
perf_event_attr:
type 6
size 120
config 0xa00000000
sample_type IDENTIFIER
read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
disabled 1
inherit 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 16 group_fd -1 flags 0x8 = 20
sys_perf_event_open: pid -1 cpu 17 group_fd -1 flags 0x8 = 21
sys_perf_event_open: pid -1 cpu 18 group_fd -1 flags 0x8 = 22
sys_perf_event_open: pid -1 cpu 19 group_fd -1 flags 0x8 = 23
sys_perf_event_open: pid -1 cpu 20 group_fd -1 flags 0x8 = 24
sys_perf_event_open: pid -1 cpu 21 group_fd -1 flags 0x8 = 25
sys_perf_event_open: pid -1 cpu 22 group_fd -1 flags 0x8 = 26
sys_perf_event_open: pid -1 cpu 23 group_fd -1 flags 0x8 = 27
cycles: 0: 1254337 1001292571 1001292571
cycles: 1: 2595141 1001279813 1001279813
cycles: 2: 134853 1001276406 1001276406
cycles: 3: 81119 1001271089 1001271089
cycles: 4: 251353 1001264678 1001264678
cycles: 5: 415593 1001259163 1001259163
cycles: 6: 129643 1001265312 1001265312
cycles: 7: 80289 1001258979 1001258979
cycles: 8: 169983 1001251207 1001251207
cycles: 9: 81981 1001245487 1001245487
cycles: 10: 4116221 1001245537 1001245537
cycles: 11: 85531 1001253097 1001253097
cycles: 12: 3969132 1001254270 1001254270
cycles: 13: 96006 1001254691 1001254691
cycles: 14: 385004 1001244971 1001244971
cycles: 15: 394446 1001251437 1001251437
cycles: 0: 427330 1001253457 1001253457
cycles: 1: 444043 1001255914 1001255914
cycles: 2: 97285 1001253555 1001253555
cycles: 3: 92071 1001260556 1001260556
cycles: 4: 86292 1001249896 1001249896
cycles: 5: 236851 1001238979 1001238979
cycles: 6: 100081 1001239792 1001239792
cycles: 7: 72836 1001243276 1001243276
cycles: 14240632 16020168708 16020168708
cycles: 1556789 8009995425 8009995425

Performance counter stats for 'system wide':

14,240,632 cycles
1,556,789 cycles

1.002261231 seconds time elapsed

type 6 is PERF_TYPE_HARDWARE_PMU.
0x4 in 0x400000000 indicates the cpu_core pmu.
0xa in 0xa00000000 indicates the cpu_atom pmu.

Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
tools/perf/util/parse-events.c | 73 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 73 insertions(+)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 81a6fce..1e767dc 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -446,6 +446,24 @@ static int config_attr(struct perf_event_attr *attr,
struct parse_events_error *err,
config_term_func_t config_term);

+static void config_hybrid_attr(struct perf_event_attr *attr,
+ int type, int pmu_type)
+{
+ /*
+ * attr.config layout:
+ * PERF_TYPE_HARDWARE_PMU: 0xDD000000AA
+ * AA: hardware event ID
+ * DD: PMU type ID
+ * PERF_TYPE_HW_CACHE_PMU: 0xDD00CCBBAA
+ * AA: hardware cache ID
+ * BB: hardware cache op ID
+ * CC: hardware cache op result ID
+ * DD: PMU type ID
+ */
+ attr->type = type;
+ attr->config = attr->config | ((__u64)pmu_type << PERF_PMU_TYPE_SHIFT);
+}
+
int parse_events_add_cache(struct list_head *list, int *idx,
char *type, char *op_result1, char *op_result2,
struct parse_events_error *err,
@@ -1409,6 +1427,47 @@ int parse_events_add_tracepoint(struct list_head *list, int *idx,
err, head_config);
}

+static int create_hybrid_hw_event(struct parse_events_state *parse_state,
+ struct list_head *list,
+ struct perf_event_attr *attr,
+ struct perf_pmu *pmu)
+{
+ struct evsel *evsel;
+ __u32 type = attr->type;
+ __u64 config = attr->config;
+
+ config_hybrid_attr(attr, PERF_TYPE_HARDWARE_PMU, pmu->type);
+ evsel = __add_event(list, &parse_state->idx, attr, true, NULL,
+ pmu, NULL, false, NULL);
+ if (evsel)
+ evsel->pmu_name = strdup(pmu->name);
+ else
+ return -ENOMEM;
+
+ attr->type = type;
+ attr->config = config;
+ return 0;
+}
+
+static int add_hybrid_numeric(struct parse_events_state *parse_state,
+ struct list_head *list,
+ struct perf_event_attr *attr,
+ bool *hybrid)
+{
+ struct perf_pmu *pmu;
+ int ret;
+
+ *hybrid = false;
+ perf_pmu__for_each_hybrid_pmus(pmu) {
+ *hybrid = true;
+ ret = create_hybrid_hw_event(parse_state, list, attr, pmu);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
int parse_events_add_numeric(struct parse_events_state *parse_state,
struct list_head *list,
u32 type, u64 config,
@@ -1416,6 +1475,8 @@ int parse_events_add_numeric(struct parse_events_state *parse_state,
{
struct perf_event_attr attr;
LIST_HEAD(config_terms);
+ bool hybrid;
+ int ret;

memset(&attr, 0, sizeof(attr));
attr.type = type;
@@ -1430,6 +1491,18 @@ int parse_events_add_numeric(struct parse_events_state *parse_state,
return -ENOMEM;
}

+ /*
+ * Skip the software dummy event.
+ */
+ if (type != PERF_TYPE_SOFTWARE) {
+ if (!perf_pmu__hybrid_exist())
+ perf_pmu__scan(NULL);
+
+ ret = add_hybrid_numeric(parse_state, list, &attr, &hybrid);
+ if (hybrid)
+ return ret;
+ }
+
return add_event(list, &parse_state->idx, &attr,
get_config_name(head_config), &config_terms);
}
--
2.7.4