drm: Print the pid when debug logging an ioctl error.

When we debug print what ioctl we're calling into, we include the pid.
If you have multiple processes rendering simulataneously, the error
return also needs the pid so you can see which of the ioctl calls was
the one to fail.

Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20180130215643.11016-1-eric@anholt.net
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index b1e96fb68ea8868052e2c365374f3e3a07f33ba3..af782911c505d49944fbc03ec36b1f52296529b1 100644 (file)
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -848,7 +848,7 @@ long drm_ioctl(struct file *filp,
        if (kdata != stack_kdata)
                kfree(kdata);
        if (retcode)
-               DRM_DEBUG("ret = %d\n", retcode);
+               DRM_DEBUG("pid=%d, ret = %d\n", task_pid_nr(current), retcode);
        return retcode;
 }
 EXPORT_SYMBOL(drm_ioctl);