[PATCH 1/5] drm/msm: Remove unnecessary struct_mutex

From: Rob Clark
Date: Tue Nov 09 2021 - 13:06:23 EST


From: Rob Clark <robdclark@xxxxxxxxxxxx>

The struct_mutex locking is a remnant from the days before per-obj locks,
and no longer needed.

Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_debugfs.c | 37 ++++++++++---------------------
drivers/gpu/drm/msm/msm_fbdev.c | 13 ++++-------
2 files changed, 16 insertions(+), 34 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_debugfs.c b/drivers/gpu/drm/msm/msm_debugfs.c
index dee13fedee3b..698e86f5b960 100644
--- a/drivers/gpu/drm/msm/msm_debugfs.c
+++ b/drivers/gpu/drm/msm/msm_debugfs.c
@@ -134,8 +134,10 @@ DEFINE_SIMPLE_ATTRIBUTE(shrink_fops,
"0x%08llx\n");


-static int msm_gem_show(struct drm_device *dev, struct seq_file *m)
+static int msm_gem_show(struct seq_file *m, void *arg)
{
+ struct drm_info_node *node = (struct drm_info_node *) m->private;
+ struct drm_device *dev = node->minor->dev;
struct msm_drm_private *priv = dev->dev_private;
int ret;

@@ -150,8 +152,10 @@ static int msm_gem_show(struct drm_device *dev, struct seq_file *m)
return 0;
}

-static int msm_mm_show(struct drm_device *dev, struct seq_file *m)
+static int msm_mm_show(struct seq_file *m, void *arg)
{
+ struct drm_info_node *node = (struct drm_info_node *) m->private;
+ struct drm_device *dev = node->minor->dev;
struct drm_printer p = drm_seq_file_printer(m);

drm_mm_print(&dev->vma_offset_manager->vm_addr_space_mm, &p);
@@ -159,8 +163,10 @@ static int msm_mm_show(struct drm_device *dev, struct seq_file *m)
return 0;
}

-static int msm_fb_show(struct drm_device *dev, struct seq_file *m)
+static int msm_fb_show(struct seq_file *m, void *arg)
{
+ struct drm_info_node *node = (struct drm_info_node *) m->private;
+ struct drm_device *dev = node->minor->dev;
struct msm_drm_private *priv = dev->dev_private;
struct drm_framebuffer *fb, *fbdev_fb = NULL;

@@ -183,29 +189,10 @@ static int msm_fb_show(struct drm_device *dev, struct seq_file *m)
return 0;
}

-static int show_locked(struct seq_file *m, void *arg)
-{
- struct drm_info_node *node = (struct drm_info_node *) m->private;
- struct drm_device *dev = node->minor->dev;
- int (*show)(struct drm_device *dev, struct seq_file *m) =
- node->info_ent->data;
- int ret;
-
- ret = mutex_lock_interruptible(&dev->struct_mutex);
- if (ret)
- return ret;
-
- ret = show(dev, m);
-
- mutex_unlock(&dev->struct_mutex);
-
- return ret;
-}
-
static struct drm_info_list msm_debugfs_list[] = {
- {"gem", show_locked, 0, msm_gem_show},
- { "mm", show_locked, 0, msm_mm_show },
- { "fb", show_locked, 0, msm_fb_show },
+ {"gem", msm_gem_show},
+ { "mm", msm_mm_show },
+ { "fb", msm_fb_show },
};

static int late_init_minor(struct drm_minor *minor)
diff --git a/drivers/gpu/drm/msm/msm_fbdev.c b/drivers/gpu/drm/msm/msm_fbdev.c
index 0daaeb54ff6f..4c39ef9dd75d 100644
--- a/drivers/gpu/drm/msm/msm_fbdev.c
+++ b/drivers/gpu/drm/msm/msm_fbdev.c
@@ -81,8 +81,6 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,

bo = msm_framebuffer_bo(fb, 0);

- mutex_lock(&dev->struct_mutex);
-
/*
* NOTE: if we can be guaranteed to be able to map buffer
* in panic (ie. lock-safe, etc) we could avoid pinning the
@@ -91,14 +89,14 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
if (ret) {
DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
- goto fail_unlock;
+ goto fail;
}

fbi = drm_fb_helper_alloc_fbi(helper);
if (IS_ERR(fbi)) {
DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
ret = PTR_ERR(fbi);
- goto fail_unlock;
+ goto fail;
}

DBG("fbi=%p, dev=%p", fbi, dev);
@@ -115,7 +113,7 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
fbi->screen_base = msm_gem_get_vaddr(bo);
if (IS_ERR(fbi->screen_base)) {
ret = PTR_ERR(fbi->screen_base);
- goto fail_unlock;
+ goto fail;
}
fbi->screen_size = bo->size;
fbi->fix.smem_start = paddr;
@@ -124,12 +122,9 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);

- mutex_unlock(&dev->struct_mutex);
-
return 0;

-fail_unlock:
- mutex_unlock(&dev->struct_mutex);
+fail:
drm_framebuffer_remove(fb);
return ret;
}
--
2.31.1