sound: rawmidi: record a substream's owner process

Record the pid of the task that opened a RawMIDI substream.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 9 insertions, 0 deletions

diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 818b1299ed91..2f766123b158 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -278,6 +278,7 @@ static int open_substream(struct snd_rawmidi *rmidi,
                 substream->active_sensing = 0;
                 if (mode & SNDRV_RAWMIDI_LFLG_APPEND)
                         substream->append = 1;
+                substream->pid = get_pid(task_pid(current));
                 rmidi->streams[substream->stream].substream_opened++;
         }
         substream->use_count++;
@@ -488,6 +489,8 @@ static void close_substream(struct snd_rawmidi *rmidi,
         snd_rawmidi_runtime_free(substream);
         substream->opened = 0;
         substream->append = 0;
+        put_pid(substream->pid);
+        substream->pid = NULL;
         rmidi->streams[substream->stream].substream_opened--;
 }
 
@@ -1336,6 +1339,9 @@ static void snd_rawmidi_proc_info_read(struct snd_info_entry *entry,
                                     substream->number,
                                     (unsigned long) substream->bytes);
                         if (substream->opened) {
+                                snd_iprintf(buffer,
+                                    "  Owner PID    : %d\n",
+                                    pid_vnr(substream->pid));
                                 runtime = substream->runtime;
                                 snd_iprintf(buffer,
                                     "  Mode         : %s\n"
@@ -1357,6 +1363,9 @@ static void snd_rawmidi_proc_info_read(struct snd_info_entry *entry,
                                     substream->number,
                                     (unsigned long) substream->bytes);
                         if (substream->opened) {
+                                snd_iprintf(buffer,
+                                            "  Owner PID    : %d\n",
+                                            pid_vnr(substream->pid));
                                 runtime = substream->runtime;
                                 snd_iprintf(buffer,
                                             "  Buffer size  : %lu\n"