Re: [PATCH 3/4] binder: Make transaction_log available in binderfs

[Todd Kjos <tkjos@google.com>]

On Wed, Aug 28, 2019 at 5:59 AM Christian Brauner
<christian.brauner@ubuntu.com> wrote:
>
> On Tue, Aug 27, 2019 at 01:41:51PM -0700, Hridya Valsaraju wrote:
> > Currently, the binder transaction log files 'transaction_log'
> > and 'failed_transaction_log' live in debugfs at the following locations:
> >
> > /sys/kernel/debug/binder/failed_transaction_log
> > /sys/kernel/debug/binder/transaction_log
> >
> > This patch makes these files also available in a binderfs instance
> > mounted with the mount option "stats=global".
> > It does not affect the presence of these files in debugfs.
> > If a binderfs instance is mounted at path /dev/binderfs, the location of
> > these files will be as follows:
> >
> > /dev/binderfs/binder_logs/failed_transaction_log
> > /dev/binderfs/binder_logs/transaction_log
> >
> > This change provides an alternate option to access these files when
> > debugfs is not mounted.
> >
> > Signed-off-by: Hridya Valsaraju <hridya@google.com>
>
> Acked-by: Christian Brauner <christian.brauner@ubuntu.com>

Acked-by: Todd Kjos <tkjos@google.com>

>
> > ---
> >  drivers/android/binder.c          | 34 +++++--------------------------
> >  drivers/android/binder_internal.h | 30 +++++++++++++++++++++++++++
> >  drivers/android/binderfs.c        | 19 +++++++++++++++++
> >  3 files changed, 54 insertions(+), 29 deletions(-)
> >
> > diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> > index de795bd229c4..bed217310197 100644
> > --- a/drivers/android/binder.c
> > +++ b/drivers/android/binder.c
> > @@ -197,30 +197,8 @@ static inline void binder_stats_created(enum binder_stat_types type)
> >       atomic_inc(&binder_stats.obj_created[type]);
> >  }
> >
> > -struct binder_transaction_log_entry {
> > -     int debug_id;
> > -     int debug_id_done;
> > -     int call_type;
> > -     int from_proc;
> > -     int from_thread;
> > -     int target_handle;
> > -     int to_proc;
> > -     int to_thread;
> > -     int to_node;
> > -     int data_size;
> > -     int offsets_size;
> > -     int return_error_line;
> > -     uint32_t return_error;
> > -     uint32_t return_error_param;
> > -     const char *context_name;
> > -};
> > -struct binder_transaction_log {
> > -     atomic_t cur;
> > -     bool full;
> > -     struct binder_transaction_log_entry entry[32];
> > -};
> > -static struct binder_transaction_log binder_transaction_log;
> > -static struct binder_transaction_log binder_transaction_log_failed;
> > +struct binder_transaction_log binder_transaction_log;
> > +struct binder_transaction_log binder_transaction_log_failed;
> >
> >  static struct binder_transaction_log_entry *binder_transaction_log_add(
> >       struct binder_transaction_log *log)
> > @@ -6166,7 +6144,7 @@ static void print_binder_transaction_log_entry(struct seq_file *m,
> >                       "\n" : " (incomplete)\n");
> >  }
> >
> > -static int transaction_log_show(struct seq_file *m, void *unused)
> > +int binder_transaction_log_show(struct seq_file *m, void *unused)
> >  {
> >       struct binder_transaction_log *log = m->private;
> >       unsigned int log_cur = atomic_read(&log->cur);
> > @@ -6198,8 +6176,6 @@ const struct file_operations binder_fops = {
> >       .release = binder_release,
> >  };
> >
> > -DEFINE_SHOW_ATTRIBUTE(transaction_log);
> > -
> >  static int __init init_binder_device(const char *name)
> >  {
> >       int ret;
> > @@ -6268,12 +6244,12 @@ static int __init binder_init(void)
> >                                   0444,
> >                                   binder_debugfs_dir_entry_root,
> >                                   &binder_transaction_log,
> > -                                 &transaction_log_fops);
> > +                                 &binder_transaction_log_fops);
> >               debugfs_create_file("failed_transaction_log",
> >                                   0444,
> >                                   binder_debugfs_dir_entry_root,
> >                                   &binder_transaction_log_failed,
> > -                                 &transaction_log_fops);
> > +                                 &binder_transaction_log_fops);
> >       }
> >
> >       if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) &&
> > diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
> > index 12ef96f256c6..b9be42d9464c 100644
> > --- a/drivers/android/binder_internal.h
> > +++ b/drivers/android/binder_internal.h
> > @@ -65,4 +65,34 @@ DEFINE_SHOW_ATTRIBUTE(binder_state);
> >
> >  int binder_transactions_show(struct seq_file *m, void *unused);
> >  DEFINE_SHOW_ATTRIBUTE(binder_transactions);
> > +
> > +int binder_transaction_log_show(struct seq_file *m, void *unused);
> > +DEFINE_SHOW_ATTRIBUTE(binder_transaction_log);
> > +
> > +struct binder_transaction_log_entry {
> > +     int debug_id;
> > +     int debug_id_done;
> > +     int call_type;
> > +     int from_proc;
> > +     int from_thread;
> > +     int target_handle;
> > +     int to_proc;
> > +     int to_thread;
> > +     int to_node;
> > +     int data_size;
> > +     int offsets_size;
> > +     int return_error_line;
> > +     uint32_t return_error;
> > +     uint32_t return_error_param;
> > +     const char *context_name;
> > +};
> > +
> > +struct binder_transaction_log {
> > +     atomic_t cur;
> > +     bool full;
> > +     struct binder_transaction_log_entry entry[32];
> > +};
> > +
> > +extern struct binder_transaction_log binder_transaction_log;
> > +extern struct binder_transaction_log binder_transaction_log_failed;
> >  #endif /* _LINUX_BINDER_INTERNAL_H */
> > diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c
> > index d542f9b8d8ab..dc25a7d759c9 100644
> > --- a/drivers/android/binderfs.c
> > +++ b/drivers/android/binderfs.c
> > @@ -630,8 +630,27 @@ static int init_binder_logs(struct super_block *sb)
> >
> >       file_dentry = binderfs_create_file(binder_logs_root_dir, "transactions",
> >                                          &binder_transactions_fops, NULL);
> > +     if (IS_ERR(file_dentry)) {
> > +             ret = PTR_ERR(file_dentry);
> > +             goto out;
> > +     }
> > +
> > +     file_dentry = binderfs_create_file(binder_logs_root_dir,
> > +                                        "transaction_log",
> > +                                        &binder_transaction_log_fops,
> > +                                        &binder_transaction_log);
> > +     if (IS_ERR(file_dentry)) {
> > +             ret = PTR_ERR(file_dentry);
> > +             goto out;
> > +     }
> > +
> > +     file_dentry = binderfs_create_file(binder_logs_root_dir,
> > +                                        "failed_transaction_log",
> > +                                        &binder_transaction_log_fops,
> > +                                        &binder_transaction_log_failed);
> >       if (IS_ERR(file_dentry))
> >               ret = PTR_ERR(file_dentry);
> > +
> >  out:
> >       return ret;
> >  }
> > --
> > 2.23.0.187.g17f5b7556c-goog
> >