Merge tag 'perf-core-for-mingo-4.15-20171003' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

- Multithread the synthesizing of PERF_RECORD_ events for pre-existing
  threads in 'perf top', speeding up that phase, greatly improving the
  user experience in systems such as Intel's Knights Mill (Kan Liang)

- 'perf test' fixes for the perf_event_attr test case (Jiri Olsa, Thomas Richter)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 48 insertions, 5 deletions

diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index c09bdb509d82..bf73117b4822 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -45,6 +45,8 @@ struct thread *thread__new(pid_t pid, pid_t tid)
                 thread->cpu = -1;
                 INIT_LIST_HEAD(&thread->namespaces_list);
                 INIT_LIST_HEAD(&thread->comm_list);
+                init_rwsem(&thread->namespaces_lock);
+                init_rwsem(&thread->comm_lock);
 
                 comm_str = malloc(32);
                 if (!comm_str)
@@ -83,18 +85,26 @@ void thread__delete(struct thread *thread)
                 map_groups__put(thread->mg);
                 thread->mg = NULL;
         }
+        down_write(&thread->namespaces_lock);
         list_for_each_entry_safe(namespaces, tmp_namespaces,
                                  &thread->namespaces_list, list) {
                 list_del(&namespaces->list);
                 namespaces__free(namespaces);
         }
+        up_write(&thread->namespaces_lock);
+
+        down_write(&thread->comm_lock);
         list_for_each_entry_safe(comm, tmp_comm, &thread->comm_list, list) {
                 list_del(&comm->list);
                 comm__free(comm);
         }
+        up_write(&thread->comm_lock);
+
         unwind__finish_access(thread);
         nsinfo__zput(thread->nsinfo);
 
+        exit_rwsem(&thread->namespaces_lock);
+        exit_rwsem(&thread->comm_lock);
         free(thread);
 }
 
@@ -125,8 +135,8 @@ struct namespaces *thread__namespaces(const struct thread *thread)
         return list_first_entry(&thread->namespaces_list, struct namespaces, list);
 }
 
-int thread__set_namespaces(struct thread *thread, u64 timestamp,
-                           struct namespaces_event *event)
+static int __thread__set_namespaces(struct thread *thread, u64 timestamp,
+                                    struct namespaces_event *event)
 {
         struct namespaces *new, *curr = thread__namespaces(thread);
 
@@ -149,6 +159,17 @@ int thread__set_namespaces(struct thread *thread, u64 timestamp,
         return 0;
 }
 
+int thread__set_namespaces(struct thread *thread, u64 timestamp,
+                           struct namespaces_event *event)
+{
+        int ret;
+
+        down_write(&thread->namespaces_lock);
+        ret = __thread__set_namespaces(thread, timestamp, event);
+        up_write(&thread->namespaces_lock);
+        return ret;
+}
+
 struct comm *thread__comm(const struct thread *thread)
 {
         if (list_empty(&thread->comm_list))
@@ -170,8 +191,8 @@ struct comm *thread__exec_comm(const struct thread *thread)
         return last;
 }
 
-int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
-                       bool exec)
+static int ____thread__set_comm(struct thread *thread, const char *str,
+                                u64 timestamp, bool exec)
 {
         struct comm *new, *curr = thread__comm(thread);
 
@@ -195,6 +216,17 @@ int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
         return 0;
 }
 
+int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
+                       bool exec)
+{
+        int ret;
+
+        down_write(&thread->comm_lock);
+        ret = ____thread__set_comm(thread, str, timestamp, exec);
+        up_write(&thread->comm_lock);
+        return ret;
+}
+
 int thread__set_comm_from_proc(struct thread *thread)
 {
         char path[64];
@@ -212,7 +244,7 @@ int thread__set_comm_from_proc(struct thread *thread)
         return err;
 }
 
-const char *thread__comm_str(const struct thread *thread)
+static const char *__thread__comm_str(const struct thread *thread)
 {
         const struct comm *comm = thread__comm(thread);
 
@@ -222,6 +254,17 @@ const char *thread__comm_str(const struct thread *thread)
         return comm__str(comm);
 }
 
+const char *thread__comm_str(const struct thread *thread)
+{
+        const char *str;
+
+        down_read((struct rw_semaphore *)&thread->comm_lock);
+        str = __thread__comm_str(thread);
+        up_read((struct rw_semaphore *)&thread->comm_lock);
+
+        return str;
+}
+
 /* CHECKME: it should probably better return the max comm len from its comm list */
 int thread__comm_len(struct thread *thread)
 {