perf tools: Share map_groups among threads of the same group
authorJiri Olsa <jolsa@kernel.org>
Wed, 9 Apr 2014 18:54:29 +0000 (20:54 +0200)
committerJiri Olsa <jolsa@kernel.org>
Mon, 28 Apr 2014 11:43:33 +0000 (13:43 +0200)
Sharing map groups within all process threads. This way
there's only one copy of mmap info and it's reachable
from any thread within the process.

Original-patch-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1397490723-1992-5-git-send-email-jolsa@redhat.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
tools/perf/util/machine.c
tools/perf/util/thread.c
tools/perf/util/thread.h

index a53cd0b8c151cdb898d3711c36e5081846813a15..98ec56dc890bf50da68dd374d401ebb61923e68c 100644 (file)
@@ -316,6 +316,17 @@ static struct thread *__machine__findnew_thread(struct machine *machine,
                rb_link_node(&th->rb_node, parent, p);
                rb_insert_color(&th->rb_node, &machine->threads);
                machine->last_match = th;
+
+               /*
+                * We have to initialize map_groups separately
+                * after rb tree is updated.
+                *
+                * The reason is that we call machine__findnew_thread
+                * within thread__init_map_groups to find the thread
+                * leader and that would screwed the rb tree.
+                */
+               if (thread__init_map_groups(th, machine))
+                       return NULL;
        }
 
        return th;
index b501848a8424cc2483232cba02520f5a95c8d140..2fde0d5e40b5f4ef409b1be27197043bbf740a3f 100644 (file)
@@ -8,6 +8,22 @@
 #include "debug.h"
 #include "comm.h"
 
+int thread__init_map_groups(struct thread *thread, struct machine *machine)
+{
+       struct thread *leader;
+       pid_t pid = thread->pid_;
+
+       if (pid == thread->tid) {
+               thread->mg = map_groups__new();
+       } else {
+               leader = machine__findnew_thread(machine, pid, pid);
+               if (leader)
+                       thread->mg = map_groups__get(leader->mg);
+       }
+
+       return thread->mg ? 0 : -1;
+}
+
 struct thread *thread__new(pid_t pid, pid_t tid)
 {
        char *comm_str;
@@ -15,10 +31,6 @@ struct thread *thread__new(pid_t pid, pid_t tid)
        struct thread *thread = zalloc(sizeof(*thread));
 
        if (thread != NULL) {
-               thread->mg = map_groups__new();
-               if (thread->mg == NULL)
-                       goto out_free;
-
                thread->pid_ = pid;
                thread->tid = tid;
                thread->ppid = -1;
@@ -40,8 +52,6 @@ struct thread *thread__new(pid_t pid, pid_t tid)
        return thread;
 
 err_thread:
-       map_groups__delete(thread->mg);
-out_free:
        free(thread);
        return NULL;
 }
@@ -126,9 +136,26 @@ void thread__insert_map(struct thread *thread, struct map *map)
        map_groups__insert(thread->mg, map);
 }
 
+static int thread__clone_map_groups(struct thread *thread,
+                                   struct thread *parent)
+{
+       int i;
+
+       /* This is new thread, we share map groups for process. */
+       if (thread->pid_ == parent->pid_)
+               return 0;
+
+       /* But this one is new process, copy maps. */
+       for (i = 0; i < MAP__NR_TYPES; ++i)
+               if (map_groups__clone(thread->mg, parent->mg, i) < 0)
+                       return -ENOMEM;
+
+       return 0;
+}
+
 int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp)
 {
-       int i, err;
+       int err;
 
        if (parent->comm_set) {
                const char *comm = thread__comm_str(parent);
@@ -140,13 +167,8 @@ int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp)
                thread->comm_set = true;
        }
 
-       for (i = 0; i < MAP__NR_TYPES; ++i)
-               if (map_groups__clone(thread->mg, parent->mg, i) < 0)
-                       return -ENOMEM;
-
        thread->ppid = parent->tid;
-
-       return 0;
+       return thread__clone_map_groups(thread, parent);
 }
 
 void thread__find_cpumode_addr_location(struct thread *thread,
index bee1eb0f73bcd1cc1a7d2336545e09779d39f0a5..3c0c2724f82c718dc02153acaf08b9a46bbac5ce 100644 (file)
@@ -30,6 +30,7 @@ struct machine;
 struct comm;
 
 struct thread *thread__new(pid_t pid, pid_t tid);
+int thread__init_map_groups(struct thread *thread, struct machine *machine);
 void thread__delete(struct thread *thread);
 static inline void thread__exited(struct thread *thread)
 {