[PATCH 07/16] perf auxtrace: For reporting purposes, un-group AUX area event

From: Adrian Hunter
Date: Wed Apr 01 2020 - 06:18:31 EST


An AUX area event must be the group leader when recording traces in
sample mode, but that does not produce the expected results from
'perf report' because it expects the leader to provide samples. Rather
than teach 'perf report' about AUX area sampling, un-group the AUX
area event during processing, making the 2nd event the leader.

Example:

$ perf record -e '{intel_pt//u,branch-misses:u}' -c 1 uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.080 MB perf.data ]

Before:

$ perf report

Samples: 800 of events 'anon group { intel_pt//u, branch-misses:u }', Event count (approx.): 800
Children Self Command Shared Object Symbol
0.00% 47.50% 0.00% 47.50% uname libc-2.28.so [.] _dl_addr
0.00% 16.38% 0.00% 16.38% uname ld-2.28.so [.] __GI___tunables_init
0.00% 54.75% 0.00% 4.75% uname ld-2.28.so [.] dl_main
0.00% 3.12% 0.00% 3.12% uname ld-2.28.so [.] _dl_map_object_from_fd
0.00% 2.38% 0.00% 2.38% uname ld-2.28.so [.] strcmp
0.00% 2.25% 0.00% 2.25% uname ld-2.28.so [.] _dl_check_map_versions
0.00% 2.00% 0.00% 2.00% uname ld-2.28.so [.] _dl_important_hwcaps
0.00% 2.00% 0.00% 2.00% uname ld-2.28.so [.] _dl_map_object_deps
0.00% 51.50% 0.00% 1.50% uname ld-2.28.so [.] _dl_sysdep_start
0.00% 1.25% 0.00% 1.25% uname ld-2.28.so [.] _dl_load_cache_lookup
0.00% 51.12% 0.00% 1.12% uname ld-2.28.so [.] _dl_start
0.00% 50.88% 0.00% 1.12% uname ld-2.28.so [.] do_lookup_x
0.00% 50.62% 0.00% 1.00% uname ld-2.28.so [.] _dl_lookup_symbol_x
0.00% 1.00% 0.00% 1.00% uname ld-2.28.so [.] _dl_map_object
0.00% 1.00% 0.00% 1.00% uname ld-2.28.so [.] _dl_next_ld_env_entry
0.00% 0.88% 0.00% 0.88% uname ld-2.28.so [.] _dl_cache_libcmp
0.00% 0.88% 0.00% 0.88% uname ld-2.28.so [.] _dl_new_object
0.00% 50.88% 0.00% 0.88% uname ld-2.28.so [.] _dl_relocate_object
0.00% 0.62% 0.00% 0.62% uname ld-2.28.so [.] _dl_init_paths
0.00% 0.62% 0.00% 0.62% uname ld-2.28.so [.] _dl_name_match_p
0.00% 0.50% 0.00% 0.50% uname ld-2.28.so [.] get_common_indeces.constprop.1
0.00% 0.50% 0.00% 0.50% uname ld-2.28.so [.] memmove
0.00% 0.50% 0.00% 0.50% uname ld-2.28.so [.] memset
0.00% 0.50% 0.00% 0.50% uname ld-2.28.so [.] open_verify.constprop.11
0.00% 0.38% 0.00% 0.38% uname ld-2.28.so [.] _dl_check_all_versions
0.00% 0.38% 0.00% 0.38% uname ld-2.28.so [.] _dl_find_dso_for_object
0.00% 0.38% 0.00% 0.38% uname ld-2.28.so [.] init_tls
0.00% 0.25% 0.00% 0.25% uname ld-2.28.so [.] __tunable_get_val
0.00% 0.25% 0.00% 0.25% uname ld-2.28.so [.] _dl_add_to_namespace_list
0.00% 0.25% 0.00% 0.25% uname ld-2.28.so [.] _dl_determine_tlsoffset
0.00% 0.25% 0.00% 0.25% uname ld-2.28.so [.] _dl_discover_osversion
0.00% 0.25% 0.00% 0.25% uname ld-2.28.so [.] calloc@plt
0.00% 0.25% 0.00% 0.25% uname ld-2.28.so [.] malloc
0.00% 0.25% 0.00% 0.25% uname ld-2.28.so [.] malloc@plt
0.00% 0.25% 0.00% 0.25% uname libc-2.28.so [.] _nl_load_locale_from_archive
0.00% 0.25% 0.00% 0.25% uname [unknown] [k] 0xffffffffa3a00010
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] __libc_scratch_buffer_set_array_size
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] _dl_allocate_tls_storage
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] _dl_catch_exception
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] _dl_setup_hash
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] _dl_sort_maps
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] _dl_sysdep_read_whole_file
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] access
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] calloc
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] mmap64
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] openaux
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] rtld_lock_default_lock_recursive
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] rtld_lock_default_unlock_recursive
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] strchr
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] strlen
0.00% 0.12% 0.00% 0.12% uname ld-2.28.so [.] 0x0000000000001080
0.00% 0.12% 0.00% 0.12% uname libc-2.28.so [.] __strchrnul_avx2
0.00% 0.12% 0.00% 0.12% uname libc-2.28.so [.] _nl_normalize_codeset
0.00% 0.12% 0.00% 0.12% uname libc-2.28.so [.] malloc
0.00% 0.12% 0.00% 0.12% uname [unknown] [k] 0xffffffffa3a011f0
0.00% 50.00% 0.00% 0.00% uname ld-2.28.so [.] _dl_start_user
0.00% 50.00% 0.00% 0.00% uname [unknown] [.] 0000000000000000

After:

Samples: 800 of event 'branch-misses:u', Event count (approx.): 800
Children Self Command Shared Object Symbol
54.75% 4.75% uname ld-2.28.so [.] dl_main
51.50% 1.50% uname ld-2.28.so [.] _dl_sysdep_start
51.12% 1.12% uname ld-2.28.so [.] _dl_start
50.88% 0.88% uname ld-2.28.so [.] _dl_relocate_object
50.88% 1.12% uname ld-2.28.so [.] do_lookup_x
50.62% 1.00% uname ld-2.28.so [.] _dl_lookup_symbol_x
50.00% 0.00% uname ld-2.28.so [.] _dl_start_user
50.00% 0.00% uname [unknown] [.] 0000000000000000
47.50% 47.50% uname libc-2.28.so [.] _dl_addr
16.38% 16.38% uname ld-2.28.so [.] __GI___tunables_init
3.12% 3.12% uname ld-2.28.so [.] _dl_map_object_from_fd
2.38% 2.38% uname ld-2.28.so [.] strcmp
2.25% 2.25% uname ld-2.28.so [.] _dl_check_map_versions
2.00% 2.00% uname ld-2.28.so [.] _dl_important_hwcaps
2.00% 2.00% uname ld-2.28.so [.] _dl_map_object_deps
1.25% 1.25% uname ld-2.28.so [.] _dl_load_cache_lookup
1.00% 1.00% uname ld-2.28.so [.] _dl_map_object
1.00% 1.00% uname ld-2.28.so [.] _dl_next_ld_env_entry
0.88% 0.88% uname ld-2.28.so [.] _dl_cache_libcmp
0.88% 0.88% uname ld-2.28.so [.] _dl_new_object
0.62% 0.62% uname ld-2.28.so [.] _dl_init_paths
0.62% 0.62% uname ld-2.28.so [.] _dl_name_match_p
0.50% 0.50% uname ld-2.28.so [.] get_common_indeces.constprop.1
0.50% 0.50% uname ld-2.28.so [.] memmove
0.50% 0.50% uname ld-2.28.so [.] memset
0.50% 0.50% uname ld-2.28.so [.] open_verify.constprop.11
0.38% 0.38% uname ld-2.28.so [.] _dl_check_all_versions
0.38% 0.38% uname ld-2.28.so [.] _dl_find_dso_for_object
0.38% 0.38% uname ld-2.28.so [.] init_tls
0.25% 0.25% uname ld-2.28.so [.] __tunable_get_val
0.25% 0.25% uname ld-2.28.so [.] _dl_add_to_namespace_list
0.25% 0.25% uname ld-2.28.so [.] _dl_determine_tlsoffset
0.25% 0.25% uname ld-2.28.so [.] _dl_discover_osversion
0.25% 0.25% uname ld-2.28.so [.] calloc@plt
0.25% 0.25% uname ld-2.28.so [.] malloc
0.25% 0.25% uname ld-2.28.so [.] malloc@plt
0.25% 0.25% uname libc-2.28.so [.] _nl_load_locale_from_archive
0.25% 0.25% uname [unknown] [k] 0xffffffffa3a00010
0.12% 0.12% uname ld-2.28.so [.] __libc_scratch_buffer_set_array_size
0.12% 0.12% uname ld-2.28.so [.] _dl_allocate_tls_storage
0.12% 0.12% uname ld-2.28.so [.] _dl_catch_exception
0.12% 0.12% uname ld-2.28.so [.] _dl_setup_hash
0.12% 0.12% uname ld-2.28.so [.] _dl_sort_maps
0.12% 0.12% uname ld-2.28.so [.] _dl_sysdep_read_whole_file
0.12% 0.12% uname ld-2.28.so [.] access
0.12% 0.12% uname ld-2.28.so [.] calloc
0.12% 0.12% uname ld-2.28.so [.] mmap64
0.12% 0.12% uname ld-2.28.so [.] openaux
0.12% 0.12% uname ld-2.28.so [.] rtld_lock_default_lock_recursive
0.12% 0.12% uname ld-2.28.so [.] rtld_lock_default_unlock_recursive
0.12% 0.12% uname ld-2.28.so [.] strchr
0.12% 0.12% uname ld-2.28.so [.] strlen
0.12% 0.12% uname ld-2.28.so [.] 0x0000000000001080
0.12% 0.12% uname libc-2.28.so [.] __strchrnul_avx2
0.12% 0.12% uname libc-2.28.so [.] _nl_normalize_codeset
0.12% 0.12% uname libc-2.28.so [.] malloc
0.12% 0.12% uname [unknown] [k] 0xffffffffa3a011f0

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
tools/perf/util/auxtrace.c | 60 ++++++++++++++++++++++++++++++++++----
1 file changed, 55 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c
index 2c4ad6838766..b60bae8e395c 100644
--- a/tools/perf/util/auxtrace.c
+++ b/tools/perf/util/auxtrace.c
@@ -1234,29 +1234,79 @@ int perf_event__synthesize_auxtrace_info(struct auxtrace_record *itr,
return err;
}

+static void unleader_evsel(struct evlist *evlist, struct evsel *leader)
+{
+ struct evsel *new_leader = NULL;
+ struct evsel *evsel;
+
+ /* Find new leader for the group */
+ evlist__for_each_entry(evlist, evsel) {
+ if (evsel->leader != leader || evsel == leader)
+ continue;
+ if (!new_leader)
+ new_leader = evsel;
+ evsel->leader = new_leader;
+ }
+
+ /* Update group information */
+ if (new_leader) {
+ zfree(&new_leader->group_name);
+ new_leader->group_name = leader->group_name;
+ leader->group_name = NULL;
+
+ new_leader->core.nr_members = leader->core.nr_members - 1;
+ leader->core.nr_members = 1;
+ }
+}
+
+static void unleader_auxtrace(struct perf_session *session)
+{
+ struct evsel *evsel;
+
+ evlist__for_each_entry(session->evlist, evsel) {
+ if (auxtrace__evsel_is_auxtrace(session, evsel) &&
+ perf_evsel__is_group_leader(evsel)) {
+ unleader_evsel(session->evlist, evsel);
+ }
+ }
+}
+
int perf_event__process_auxtrace_info(struct perf_session *session,
union perf_event *event)
{
enum auxtrace_type type = event->auxtrace_info.type;
+ int err;

if (dump_trace)
fprintf(stdout, " type: %u\n", type);

switch (type) {
case PERF_AUXTRACE_INTEL_PT:
- return intel_pt_process_auxtrace_info(event, session);
+ err = intel_pt_process_auxtrace_info(event, session);
+ break;
case PERF_AUXTRACE_INTEL_BTS:
- return intel_bts_process_auxtrace_info(event, session);
+ err = intel_bts_process_auxtrace_info(event, session);
+ break;
case PERF_AUXTRACE_ARM_SPE:
- return arm_spe_process_auxtrace_info(event, session);
+ err = arm_spe_process_auxtrace_info(event, session);
+ break;
case PERF_AUXTRACE_CS_ETM:
- return cs_etm__process_auxtrace_info(event, session);
+ err = cs_etm__process_auxtrace_info(event, session);
+ break;
case PERF_AUXTRACE_S390_CPUMSF:
- return s390_cpumsf_process_auxtrace_info(event, session);
+ err = s390_cpumsf_process_auxtrace_info(event, session);
+ break;
case PERF_AUXTRACE_UNKNOWN:
default:
return -EINVAL;
}
+
+ if (err)
+ return err;
+
+ unleader_auxtrace(session);
+
+ return 0;
}

s64 perf_event__process_auxtrace(struct perf_session *session,
--
2.17.1