[PATCH v3 2/3] panthor: save task pid and comm in panthor_group

[Chia-I Wu]

We would like to report them on gpu errors.

We choose to save the info on panthor_group_create rather than on
panthor_open because, when the two differ, we are more interested in the
task that created the group.

Signed-off-by: Chia-I Wu <olvaffe at gmail.com>
Reviewed-by: Steven Price <steven.price at arm.com>

---
v3: fix new kerneldoc warnings
v2: save to panthor_group on panthor_group_create rather than to
    panthor_file on panthor_open
---
 drivers/gpu/drm/panthor/panthor_sched.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
index a2248f692a030..9987aeb4608bc 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -641,6 +641,15 @@ struct panthor_group {
 		size_t kbo_sizes;
 	} fdinfo;
 
+	/** @task_info: Info of current->group_leader that created the group. */
+	struct {
+		/** @task_info.pid: pid of current->group_leader */
+		pid_t pid;
+
+		/** @task_info.comm: comm of current->group_leader */
+		char comm[TASK_COMM_LEN];
+	} task_info;
+
 	/** @state: Group state. */
 	enum panthor_group_state state;
 
@@ -3389,6 +3398,14 @@ group_create_queue(struct panthor_group *group,
 	return ERR_PTR(ret);
 }
 
+static void group_init_task_info(struct panthor_group *group)
+{
+	struct task_struct *task = current->group_leader;
+
+	group->task_info.pid = task->pid;
+	get_task_comm(group->task_info.comm, task);
+}
+
 static void add_group_kbo_sizes(struct panthor_device *ptdev,
 				struct panthor_group *group)
 {
@@ -3540,6 +3557,8 @@ int panthor_group_create(struct panthor_file *pfile,
 	add_group_kbo_sizes(group->ptdev, group);
 	spin_lock_init(&group->fdinfo.lock);
 
+	group_init_task_info(group);
+
 	return gid;
 
 err_put_group:
-- 
2.50.0.727.gbf7dc18ff4-goog