[PATCH 1/4] perf tools: Don't set attr.exclude_guest by default

From: Namhyung Kim
Date: Sun Sep 01 2024 - 21:46:46 EST


The exclude_guest in the event attribute is to limit profiling in the
host environment. But I'm not sure why we want to set it by default
cause we don't care about it in most cases and I feel like it just
makes new PMU implementation complicated.

Of course it's useful for perf kvm command so I added the
exclude_GH_default variable to preserve the old behavior for perf kvm
and other commands like perf record and stat won't set the exclude bit.
This is helpful for AMD IBS case since having exclude_guest bit will
clear new feature bit due to the missing feature check logic.

$ sysctl kernel.perf_event_paranoid
kernel.perf_event_paranoid = 0

$ perf record -W -e ibs_op// -vv true 2>&1 | grep switching
switching off PERF_FORMAT_LOST support
switching off weight struct support
switching off bpf_event
switching off ksymbol
switching off cloexec flag
switching off mmap2
switching off exclude_guest, exclude_host

Maybe Apple M1 users will scream but actually the default event for
perf record was converted to "cycles:P" which doesn't set the
exclude_guest bit already. So they need to specify the necessary
modifier manually like "cycles:PH" and I think it's ok.

Intestingly, I found it sets the exclude_bit if "u" modifier is used.
I don't know why but it's neither intuitive nor consistent. Let's
remove the bit there too.

Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: James Clark <james.clark@xxxxxxxxxx>
Cc: Ravi Bangoria <ravi.bangoria@xxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/builtin-kvm.c | 1 +
tools/perf/tests/attr/test-record-dummy-C0 | 2 +-
tools/perf/tests/parse-events.c | 18 +++++++++---------
tools/perf/util/parse-events.c | 2 +-
tools/perf/util/util.c | 10 ++++++++--
tools/perf/util/util.h | 3 +++
6 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index 692267b1b7e8..ca94dd3de04d 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -2147,6 +2147,7 @@ int cmd_kvm(int argc, const char **argv)
"buildid-list", "stat", NULL };
const char *kvm_usage[] = { NULL, NULL };

+ exclude_HG_default = true;
perf_host = 0;
perf_guest = 1;

diff --git a/tools/perf/tests/attr/test-record-dummy-C0 b/tools/perf/tests/attr/test-record-dummy-C0
index 576ec48b3aaf..8ce6f0a5df5b 100644
--- a/tools/perf/tests/attr/test-record-dummy-C0
+++ b/tools/perf/tests/attr/test-record-dummy-C0
@@ -37,7 +37,7 @@ precise_ip=0
mmap_data=0
sample_id_all=1
exclude_host=0
-exclude_guest=1
+exclude_guest=0
exclude_callchain_kernel=0
exclude_callchain_user=0
mmap2=1
diff --git a/tools/perf/tests/parse-events.c b/tools/perf/tests/parse-events.c
index edc2adcf1bae..9179bf3084c3 100644
--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -932,7 +932,7 @@ static int test__group2(struct evlist *evlist)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", !evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong leader", evsel__is_group_leader(evsel));
@@ -947,7 +947,7 @@ static int test__group2(struct evlist *evlist)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
if (evsel__has_leader(evsel, leader))
@@ -1072,7 +1072,7 @@ static int test__group3(struct evlist *evlist __maybe_unused)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong leader", evsel__is_group_leader(evsel));
@@ -1222,7 +1222,7 @@ static int test__group5(struct evlist *evlist __maybe_unused)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", !evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", !evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong leader", evsel__is_group_leader(evsel));
@@ -1437,7 +1437,7 @@ static int test__leader_sample1(struct evlist *evlist)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", !evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", !evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong group name", !evsel->group_name);
@@ -1453,7 +1453,7 @@ static int test__leader_sample1(struct evlist *evlist)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", !evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", !evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong leader", evsel__has_leader(evsel, leader));
@@ -1468,7 +1468,7 @@ static int test__leader_sample1(struct evlist *evlist)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", !evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", !evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong group name", !evsel->group_name);
@@ -1497,7 +1497,7 @@ static int test__leader_sample2(struct evlist *evlist __maybe_unused)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong group name", !evsel->group_name);
@@ -1513,7 +1513,7 @@ static int test__leader_sample2(struct evlist *evlist __maybe_unused)
TEST_ASSERT_VAL("wrong exclude_user", !evsel->core.attr.exclude_user);
TEST_ASSERT_VAL("wrong exclude_kernel", evsel->core.attr.exclude_kernel);
TEST_ASSERT_VAL("wrong exclude_hv", evsel->core.attr.exclude_hv);
- TEST_ASSERT_VAL("wrong exclude guest", evsel->core.attr.exclude_guest);
+ TEST_ASSERT_VAL("wrong exclude guest", !evsel->core.attr.exclude_guest);
TEST_ASSERT_VAL("wrong exclude host", !evsel->core.attr.exclude_host);
TEST_ASSERT_VAL("wrong precise_ip", !evsel->core.attr.precise_ip);
TEST_ASSERT_VAL("wrong group name", !evsel->group_name);
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index fab01ba54e34..ab73b3d45f04 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1739,7 +1739,7 @@ static int parse_events__modifier_list(struct parse_events_state *parse_state,
if (mod.user) {
if (!exclude)
exclude = eu = ek = eh = 1;
- if (!exclude_GH && !perf_guest)
+ if (!exclude_GH && !perf_guest && exclude_HG_default)
eG = 1;
eu = 0;
}
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 9d55a13787ce..7e3159faaa19 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -78,17 +78,23 @@ bool sysctl__nmi_watchdog_enabled(void)

bool test_attr__enabled;

+bool exclude_HG_default;
+
bool perf_host = true;
bool perf_guest = false;

void event_attr_init(struct perf_event_attr *attr)
{
+ /* to capture ABI version */
+ attr->size = sizeof(*attr);
+
+ if (!exclude_HG_default)
+ return;
+
if (!perf_host)
attr->exclude_host = 1;
if (!perf_guest)
attr->exclude_guest = 1;
- /* to capture ABI version */
- attr->size = sizeof(*attr);
}

int mkdir_p(char *path, mode_t mode)
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 9966c21aaf04..d33ae883a54f 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -21,6 +21,9 @@ extern const char perf_more_info_string[];

extern const char *input_name;

+/* This will control if perf_{host,guest} will set attr.exclude_{host,guest}. */
+extern bool exclude_HG_default;
+
extern bool perf_host;
extern bool perf_guest;

--
2.46.0.469.g59c65b2a67-goog