[tip:perf/urgent] perf db-export: Pass main_thread to db_export__thread()

tip-bot for Adrian Hunter
2019-07-17T22:52:55Z

Commit-ID: ed5c0a16feb9f1a4347f109d5e9607f6f38688a0
Gitweb: https://git.kernel.org/tip/ed5c0a16feb9f1a4347f109d5e9607f6f38688a0
Author: Adrian Hunter <adrian.hunter@intel.com>
AuthorDate: Wed, 10 Jul 2019 11:57:52 +0300
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 10 Jul 2019 12:11:04 -0300

perf db-export: Pass main_thread to db_export__thread()

Calls to db_export__thread() already have main_thread so there is no
reason to get it again, instead pass it as a parameter. Note that one
difference in this approach is that the main thread is not created if it
does not exist. It is better if it is not created because:

- If main_thread is being traced it will have been created already.

- If it is not being traced, there will be no other information about
it, and it will never get deleted because there will be no EXIT event.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190710085810.1650-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/db-export.c | 29 ++++++++---------------------
tools/perf/util/db-export.h | 3 ++-
2 files changed, 10 insertions(+), 22 deletions(-)

diff --git a/tools/perf/util/db-export.c b/tools/perf/util/db-export.c
index 8fab57f90cbc..14501236c046 100644
--- a/tools/perf/util/db-export.c
+++ b/tools/perf/util/db-export.c
@@ -59,9 +59,9 @@ int db_export__machine(struct db_export *dbe, struct machine *machine)
}

int db_export__thread(struct db_export *dbe, struct thread *thread,
- struct machine *machine, struct comm *comm)
+ struct machine *machine, struct comm *comm,
+ struct thread *main_thread)
{
- struct thread *main_thread;
u64 main_thread_db_id = 0;
int err;

@@ -70,28 +70,19 @@ int db_export__thread(struct db_export *dbe, struct thread *thread,

thread->db_id = ++dbe->thread_last_db_id;

- if (thread->pid_ != -1) {
- if (thread->pid_ == thread->tid) {
- main_thread = thread;
- } else {
- main_thread = machine__findnew_thread(machine,
- thread->pid_,
- thread->pid_);
- if (!main_thread)
- return -ENOMEM;
+ if (main_thread) {
+ if (main_thread != thread) {
err = db_export__thread(dbe, main_thread, machine,
- comm);
+ comm, main_thread);
if (err)
- goto out_put;
+ return err;
if (comm) {
err = db_export__comm_thread(dbe, comm, thread);
if (err)
- goto out_put;
+ return err;
}
}
main_thread_db_id = main_thread->db_id;
- if (main_thread != thread)
- thread__put(main_thread);
}

if (dbe->export_thread)
@@ -99,10 +90,6 @@ int db_export__thread(struct db_export *dbe, struct thread *thread,
machine);

return 0;
-
-out_put:
- thread__put(main_thread);
- return err;
}

/*
@@ -324,7 +311,7 @@ int db_export__sample(struct db_export *dbe, union perf_event *event,
if (main_thread)
comm = machine__thread_exec_comm(al->machine, main_thread);

- err = db_export__thread(dbe, thread, al->machine, comm);
+ err = db_export__thread(dbe, thread, al->machine, comm, main_thread);
if (err)
goto out_put;

diff --git a/tools/perf/util/db-export.h b/tools/perf/util/db-export.h
index 148a657b1887..6e267321594c 100644
--- a/tools/perf/util/db-export.h
+++ b/tools/perf/util/db-export.h
@@ -75,7 +75,8 @@ void db_export__exit(struct db_export *dbe);
int db_export__evsel(struct db_export *dbe, struct perf_evsel *evsel);
int db_export__machine(struct db_export *dbe, struct machine *machine);
int db_export__thread(struct db_export *dbe, struct thread *thread,
- struct machine *machine, struct comm *comm);
+ struct machine *machine, struct comm *comm,
+ struct thread *main_thread);
int db_export__exec_comm(struct db_export *dbe, struct comm *comm,
struct thread *main_thread);
int db_export__comm_thread(struct db_export *dbe, struct comm *comm,