UPSTREAM: binder: Add binder_proc logging to binderfs
Currently /sys/kernel/debug/binder/proc contains
the debug data for every binder_proc instance.
This patch makes this information also available
in a binderfs instance mounted with a mount option
"stats=global" in addition to debugfs. The patch does
not affect the presence of the file in debugfs.
If a binderfs instance is mounted at path /dev/binderfs,
this file would be present at /dev/binderfs/binder_logs/proc.
This change provides an alternate way to access this file when debugfs
is not mounted.
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Hridya Valsaraju <hridya@google.com>
Link: https://lore.kernel.org/r/20190903161655.107408-5-hridya@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bug: 136497735
(cherry picked from commit 4feb80faf428a02d407a9ea1952004af01308765)
Change-Id: I3aa974979f2d4aebbe79ea9df30ede2813826157
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index e3b5d61..920b1ca 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -488,6 +488,7 @@ struct binder_priority {
* @inner_lock: can nest under outer_lock and/or node lock
* @outer_lock: no nesting under innor or node lock
* Lock order: 1) outer, 2) node, 3) inner
+ * @binderfs_entry: process-specific binderfs log file
*
* Bookkeeping structure for binder processes
*/
@@ -519,6 +520,7 @@ struct binder_proc {
struct binder_context *context;
spinlock_t inner_lock;
spinlock_t outer_lock;
+ struct dentry *binderfs_entry;
};
enum {
@@ -5158,6 +5160,8 @@ static int binder_open(struct inode *nodp, struct file *filp)
{
struct binder_proc *proc;
struct binder_device *binder_dev;
+ struct binderfs_info *info;
+ struct dentry *binder_binderfs_dir_entry_proc = NULL;
binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__,
current->group_leader->pid, current->pid);
@@ -5180,11 +5184,14 @@ static int binder_open(struct inode *nodp, struct file *filp)
}
/* binderfs stashes devices in i_private */
- if (is_binderfs_device(nodp))
+ if (is_binderfs_device(nodp)) {
binder_dev = nodp->i_private;
- else
+ info = nodp->i_sb->s_fs_info;
+ binder_binderfs_dir_entry_proc = info->proc_log_dir;
+ } else {
binder_dev = container_of(filp->private_data,
struct binder_device, miscdev);
+ }
proc->context = &binder_dev->context;
binder_alloc_init(&proc->alloc);
@@ -5215,6 +5222,35 @@ static int binder_open(struct inode *nodp, struct file *filp)
&proc_fops);
}
+ if (binder_binderfs_dir_entry_proc) {
+ char strbuf[11];
+ struct dentry *binderfs_entry;
+
+ snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
+ /*
+ * Similar to debugfs, the process specific log file is shared
+ * between contexts. If the file has already been created for a
+ * process, the following binderfs_create_file() call will
+ * fail with error code EEXIST if another context of the same
+ * process invoked binder_open(). This is ok since same as
+ * debugfs, the log file will contain information on all
+ * contexts of a given PID.
+ */
+ binderfs_entry = binderfs_create_file(binder_binderfs_dir_entry_proc,
+ strbuf, &proc_fops, (void *)(unsigned long)proc->pid);
+ if (!IS_ERR(binderfs_entry)) {
+ proc->binderfs_entry = binderfs_entry;
+ } else {
+ int error;
+
+ error = PTR_ERR(binderfs_entry);
+ if (error != -EEXIST) {
+ pr_warn("Unable to create file %s in binderfs (error %d)\n",
+ strbuf, error);
+ }
+ }
+ }
+
return 0;
}
@@ -5254,6 +5290,12 @@ static int binder_release(struct inode *nodp, struct file *filp)
struct binder_proc *proc = filp->private_data;
debugfs_remove(proc->debugfs_entry);
+
+ if (proc->binderfs_entry) {
+ binderfs_remove_file(proc->binderfs_entry);
+ proc->binderfs_entry = NULL;
+ }
+
binder_defer_work(proc, BINDER_DEFERRED_RELEASE);
return 0;