[PATCH v1 07/41] perf pmu-events: Add e_machine to struct pmu_events_map
From: Ian Rogers
Date: Tue Nov 03 2026 - 18:48:29 EST
The CPUID strings in the pmu-events mapfile.csv files have an
architecture specific format, such as "GenuineIntel-6-55-[56789ABCDEF]"
on x86 or a MIDR value like "0x00000000410fd0c0" on arm64. When perf is
built with JEVENTS_ARCH=all the tables of every architecture are
present and map_for_cpu() compared the host's CPUID against all of
them, even though only the host architecture's tables can match.
Record the ELF machine of each architecture's CPUIDs in struct
pmu_events_map, EM_NONE for the test and common tables, and have
map_for_cpu() only consider tables for the host's ELF machine. The 32
and 64-bit variants of x86 and PowerPC share tables.
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/pmu-events/empty-pmu-events.c | 24 +++++++++++++++-
tools/perf/pmu-events/jevents.py | 35 +++++++++++++++++++++++-
2 files changed, 57 insertions(+), 2 deletions(-)
diff --git a/tools/perf/pmu-events/empty-pmu-events.c b/tools/perf/pmu-events/empty-pmu-events.c
index 7df1552403e7..7428ffd4d70c 100644
--- a/tools/perf/pmu-events/empty-pmu-events.c
+++ b/tools/perf/pmu-events/empty-pmu-events.c
@@ -4,6 +4,8 @@
#include <pmu-events/pmu-events.h>
#include "util/header.h"
#include "util/pmu.h"
+#include <dwarf-regs.h>
+#include <elf.h>
#include <string.h>
#include <stddef.h>
@@ -5419,6 +5421,8 @@ struct pmu_metrics_table {
struct pmu_events_map {
const char *arch;
const char *cpuid;
+ /* The ELF machine of the architecture's CPUIDs, EM_NONE for test and common. */
+ uint16_t e_machine;
struct pmu_events_table event_table;
struct pmu_metrics_table metric_table;
};
@@ -5431,6 +5435,7 @@ static const struct pmu_events_map pmu_events_map[] = {
{
.arch = "common",
.cpuid = "common",
+ .e_machine = EM_NONE,
.event_table = {
.pmus = pmu_events__common,
.num_pmus = ARRAY_SIZE(pmu_events__common),
@@ -5444,6 +5449,7 @@ static const struct pmu_events_map pmu_events_map[] = {
{
.arch = "testarch",
.cpuid = "testcpu",
+ .e_machine = EM_NONE,
.event_table = {
.pmus = pmu_events__test_soc_cpu,
.num_pmus = ARRAY_SIZE(pmu_events__test_soc_cpu),
@@ -5457,6 +5463,7 @@ static const struct pmu_events_map pmu_events_map[] = {
{
.arch = 0,
.cpuid = 0,
+ .e_machine = EM_NONE,
.event_table = { 0, 0 },
.metric_table = { 0 },
}
@@ -5769,6 +5776,20 @@ int pmu_metrics_table__find_metric(const struct pmu_metrics_table *table,
return PMU_METRICS__NOT_FOUND;
}
+/*
+ * Is the map for the architecture of @e_machine? The 32 and 64-bit variants of
+ * an architecture share tables.
+ */
+static bool pmu_events_map__e_machine_matches(const struct pmu_events_map *map,
+ uint16_t e_machine)
+{
+ if (e_machine == EM_386)
+ e_machine = EM_X86_64;
+ else if (e_machine == EM_PPC)
+ e_machine = EM_PPC64;
+ return map->e_machine == e_machine;
+}
+
static const struct pmu_events_map *map_for_cpu(struct perf_cpu cpu)
{
static struct {
@@ -5809,7 +5830,8 @@ static const struct pmu_events_map *map_for_cpu(struct perf_cpu cpu)
break;
}
- if (!strcmp_cpuid_str(map->cpuid, cpuid))
+ if (pmu_events_map__e_machine_matches(map, EM_HOST) &&
+ !strcmp_cpuid_str(map->cpuid, cpuid))
break;
}
free(last_map_search.cpuid);
diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py
index 080e04b51b8c..db1b4749aec3 100755
--- a/tools/perf/pmu-events/jevents.py
+++ b/tools/perf/pmu-events/jevents.py
@@ -26,6 +26,15 @@ _sys_event_table_to_metric_table_mapping: Dict[str, str] = {}
# JsonEvent. Architecture standard events are in json files in the top
# f'{_args.starting_dir}/{_args.arch}' directory.
_arch_std_events: Dict[str, "JsonEvent"] = {}
+# The ELF machine of the CPUIDs in each architecture's mapfile.csv.
+_arch_e_machine: Dict[str, str] = {
+ 'arm64': 'EM_AARCH64',
+ 'nds32': 'EM_NDS32',
+ 'powerpc': 'EM_PPC64',
+ 'riscv': 'EM_RISCV',
+ 's390': 'EM_S390',
+ 'x86': 'EM_X86_64',
+}
# Events to write out when the table is closed
_pending_events: list["JsonEvent"] = []
# Name of events table to be written out
@@ -730,6 +739,8 @@ struct pmu_metrics_table {
struct pmu_events_map {
\tconst char *arch;
\tconst char *cpuid;
+\t/* The ELF machine of the architecture's CPUIDs, EM_NONE for test and common. */
+\tuint16_t e_machine;
\tstruct pmu_events_table event_table;
\tstruct pmu_metrics_table metric_table;
};
@@ -745,6 +756,7 @@ static const struct pmu_events_map pmu_events_map[] = {
_args.output_file.write("""{
\t.arch = "testarch",
\t.cpuid = "testcpu",
+\t.e_machine = EM_NONE,
\t.event_table = {
\t\t.pmus = pmu_events__test_soc_cpu,
\t\t.num_pmus = ARRAY_SIZE(pmu_events__test_soc_cpu),
@@ -760,6 +772,7 @@ static const struct pmu_events_map pmu_events_map[] = {
_args.output_file.write("""{
\t.arch = "common",
\t.cpuid = "common",
+\t.e_machine = EM_NONE,
\t.event_table = {
\t\t.pmus = pmu_events__common,
\t\t.num_pmus = ARRAY_SIZE(pmu_events__common),
@@ -772,6 +785,7 @@ static const struct pmu_events_map pmu_events_map[] = {
},
""")
else:
+ e_machine = _arch_e_machine[arch]
with open(f'{_args.starting_dir}/{arch}/mapfile.csv', encoding='utf-8') as csvfile:
table = csv.reader(csvfile)
first = True
@@ -798,6 +812,7 @@ static const struct pmu_events_map pmu_events_map[] = {
_args.output_file.write(f"""{{
\t.arch = "{arch}",
\t.cpuid = "{cpuid}",
+\t.e_machine = {e_machine},
\t.event_table = {{
\t\t.pmus = {event_tblname},
\t\t.num_pmus = {event_size}
@@ -814,6 +829,7 @@ static const struct pmu_events_map pmu_events_map[] = {
_args.output_file.write("""{
\t.arch = 0,
\t.cpuid = 0,
+\t.e_machine = EM_NONE,
\t.event_table = { 0, 0 },
\t.metric_table = { 0 },
}
@@ -1178,6 +1194,20 @@ int pmu_metrics_table__find_metric(const struct pmu_metrics_table *table,
\treturn PMU_METRICS__NOT_FOUND;
}
+/*
+ * Is the map for the architecture of @e_machine? The 32 and 64-bit variants of
+ * an architecture share tables.
+ */
+static bool pmu_events_map__e_machine_matches(const struct pmu_events_map *map,
+\t\t\t\t\t uint16_t e_machine)
+{
+\tif (e_machine == EM_386)
+\t\te_machine = EM_X86_64;
+\telse if (e_machine == EM_PPC)
+\t\te_machine = EM_PPC64;
+\treturn map->e_machine == e_machine;
+}
+
static const struct pmu_events_map *map_for_cpu(struct perf_cpu cpu)
{
\tstatic struct {
@@ -1218,7 +1248,8 @@ static const struct pmu_events_map *map_for_cpu(struct perf_cpu cpu)
\t\t\t\tbreak;
\t\t\t}
-\t\t\tif (!strcmp_cpuid_str(map->cpuid, cpuid))
+\t\t\tif (pmu_events_map__e_machine_matches(map, EM_HOST) &&
+\t\t\t !strcmp_cpuid_str(map->cpuid, cpuid))
\t\t\t\tbreak;
\t\t}
\t\tfree(last_map_search.cpuid);
@@ -1503,6 +1534,8 @@ such as "arm/cortex-a34".''',
#include <pmu-events/pmu-events.h>
#include "util/header.h"
#include "util/pmu.h"
+#include <dwarf-regs.h>
+#include <elf.h>
#include <string.h>
#include <stddef.h>
--
2.56.0.385.gac671c819a-goog