On 4/15/2025 2:14 PM, Tvrtko Ursulin wrote:
On 14/04/2025 18:58, Christian König wrote:
Adding Pierre-eric and Tvrtko as well.
Thanks!
Am 11.04.25 um 15:04 schrieb Sunil Khatri:
Add helper function which get the process information for
the drm_file and updates the user provided character buffer
with the information of process name and pid as a string.
Signed-off-by: Sunil Khatri <sunil.kha...@amd.com>
---
drivers/gpu/drm/drm_file.c | 30 ++++++++++++++++++++++++++++++
include/drm/drm_file.h | 1 +
2 files changed, 31 insertions(+)
diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
index cb5f22f5bbb6..4434258d21b5 100644
--- a/drivers/gpu/drm/drm_file.c
+++ b/drivers/gpu/drm/drm_file.c
@@ -965,6 +965,36 @@ void drm_show_fdinfo(struct seq_file *m, struct
file *f)
}
EXPORT_SYMBOL(drm_show_fdinfo);
+/**
+ * drm_process_info - Fill info string with process name and pid
+ * @file_priv: context of interest for process name and pid
+ * @proc_info: user char ptr to write the string to
+ * @buff_size: size of the buffer passed for the string
+ *
+ * This update the user provided buffer with process
+ * name and pid information for @file_priv
+ */
+void drm_process_info(struct drm_file *file_priv, char *proc_info,
size_t buff_size)
+{
+ struct task_struct *task;
+ struct pid *pid;
+ struct drm_device *dev = file_priv->minor->dev;
+
+ if (!proc_info) {
+ drm_err(dev, "Invalid user buffer\n");
I'd replace this with drm_WARN_ON_ONCE.
This sounds fine, will update with warn once in next version.
Another thing I would consider is avoiding the need for stack space by
exporting a logging helper instead. Something like (from patch 3/3):
drm_file_err(uq_mgr->file, "Timed out waiting for fence %p\n", f);
Which would output the client name info as a prefix or something.
I guess here we are making a generic function and nothing specific to
the driver or a feature like uq_manager. this is supposed to be a common
helper function for all drm clients
and based on drm_file. With respect to the user i guess the
driver/feature specific information can we placed in the caller itself
and thats upto the user.
Especially attractive if you add client name.
Also while here, is %p for the fence is useful? FWIW in the tracing
series we are going for %llu:%llu (context:seqno).
To be frank i dont see the fence ptr to be very useful as they are
being reused too and we do see same fence ptr again too. but this we
could improve later. I will push a new patch series for this with the
comments taken into.
Regards
Sunil Khatri
Regards,
Tvrtko
+ return;
+ }
+
+ rcu_read_lock();
+ pid = rcu_dereference(file_priv->pid);
+ task = pid_task(pid, PIDTYPE_TGID);
+ if (task)
+ snprintf(proc_info, buff_size, "comm:%s pid:%d",
task->comm, task->pid);
Looks good in general, but I think people would like to see the
optional client name here as well.
It's rather useful to have for native context.
Regards,
Christian.
+
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(drm_process_info);
+
/**
* mock_drm_getfile - Create a new struct file for the drm device
* @minor: drm minor to wrap (e.g. #drm_device.primary)
diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h
index f0ef32e9fa5e..c01b34936968 100644
--- a/include/drm/drm_file.h
+++ b/include/drm/drm_file.h
@@ -501,6 +501,7 @@ void drm_print_memory_stats(struct drm_printer *p,
void drm_show_memory_stats(struct drm_printer *p, struct
drm_file *file);
void drm_show_fdinfo(struct seq_file *m, struct file *f);
+void drm_process_info(struct drm_file *file_priv, char *proc_info,
size_t buff_size);
struct file *mock_drm_getfile(struct drm_minor *minor, unsigned
int flags);
