sync: add debugfs support

Change-Id: I8a7ea63e454fbeee1ecf17e6c3caff7c43b24734
Signed-off-by: Erik Gilling <konkers@android.com>

diff --git a/drivers/base/sync.c b/drivers/base/sync.c
index ea0b664..49fcfc4 100644 (file)
--- a/drivers/base/sync.c
+++ b/drivers/base/sync.c
@@ -14,10 +14,12 @@
  *
  */
 
+#include <linux/debugfs.h>
 #include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
+#include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/sync.h>
 #include <linux/uaccess.h>
@@ -27,10 +29,17 @@
 static void sync_fence_signal_pt(struct sync_pt *pt);
 static int _sync_pt_has_signaled(struct sync_pt *pt);
 
+static LIST_HEAD(sync_timeline_list_head);
+static DEFINE_SPINLOCK(sync_timeline_list_lock);
+
+static LIST_HEAD(sync_fence_list_head);
+static DEFINE_SPINLOCK(sync_fence_list_lock);
+
 struct sync_timeline *sync_timeline_create(const struct sync_timeline_ops *ops,
                                           int size, const char *name)
 {
        struct sync_timeline *obj;
+       unsigned long flags;
 
        if (size < sizeof(struct sync_timeline))
                return NULL;
@@ -48,9 +57,27 @@ struct sync_timeline *sync_timeline_create(const struct sync_timeline_ops *ops,
        INIT_LIST_HEAD(&obj->active_list_head);
        spin_lock_init(&obj->active_list_lock);
 
+       spin_lock_irqsave(&sync_timeline_list_lock, flags);
+       list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
+       spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
+
        return obj;
 }
 
+static void sync_timeline_free(struct sync_timeline *obj)
+{
+       unsigned long flags;
+
+       if (obj->ops->release_obj)
+               obj->ops->release_obj(obj);
+
+       spin_lock_irqsave(&sync_timeline_list_lock, flags);
+       list_del(&obj->sync_timeline_list);
+       spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
+
+       kfree(obj);
+}
+
 void sync_timeline_destroy(struct sync_timeline *obj)
 {
        unsigned long flags;
@@ -62,7 +89,7 @@ void sync_timeline_destroy(struct sync_timeline *obj)
        spin_unlock_irqrestore(&obj->child_list_lock, flags);
 
        if (needs_freeing)
-               kfree(obj);
+               sync_timeline_free(obj);
        else
                sync_timeline_signal(obj);
 }
@@ -95,7 +122,7 @@ static void sync_timeline_remove_pt(struct sync_pt *pt)
        spin_unlock_irqrestore(&obj->child_list_lock, flags);
 
        if (needs_freeing)
-               kfree(obj);
+               sync_timeline_free(obj);
 }
 
 void sync_timeline_signal(struct sync_timeline *obj)
@@ -206,6 +233,7 @@ static const struct file_operations sync_fence_fops = {
 static struct sync_fence *sync_fence_alloc(const char *name)
 {
        struct sync_fence *fence;
+       unsigned long flags;
 
        fence = kzalloc(sizeof(struct sync_fence), GFP_KERNEL);
        if (fence == NULL)
@@ -223,6 +251,11 @@ static struct sync_fence *sync_fence_alloc(const char *name)
        spin_lock_init(&fence->waiter_list_lock);
 
        init_waitqueue_head(&fence->wq);
+
+       spin_lock_irqsave(&sync_fence_list_lock, flags);
+       list_add_tail(&fence->sync_fence_list, &sync_fence_list_head);
+       spin_unlock_irqrestore(&sync_fence_list_lock, flags);
+
        return fence;
 
 err:
@@ -451,8 +484,14 @@ int sync_fence_wait(struct sync_fence *fence, long timeout)
 static int sync_fence_release(struct inode *inode, struct file *file)
 {
        struct sync_fence *fence = file->private_data;
+       unsigned long flags;
 
        sync_fence_free_pts(fence);
+
+       spin_lock_irqsave(&sync_fence_list_lock, flags);
+       list_del(&fence->sync_fence_list);
+       spin_unlock_irqrestore(&sync_fence_list_lock, flags);
+
        kfree(fence);
 
        return 0;
@@ -523,8 +562,141 @@ static long sync_fence_ioctl(struct file *file, unsigned int cmd,
 
        case SYNC_IOC_MERGE:
                return sync_fence_ioctl_merge(fence, arg);
+
        default:
                return -ENOTTY;
        }
 }
 
+#ifdef CONFIG_DEBUG_FS
+static const char *sync_status_str(int status)
+{
+       if (status > 0)
+               return "signaled";
+       else if (status == 0)
+               return "active";
+       else
+               return "error";
+}
+
+static void sync_print_pt(struct seq_file *s, struct sync_pt *pt, bool fence)
+{
+       int status = pt->status;
+       seq_printf(s, "  %s%spt %s",
+                  fence ? pt->parent->name : "",
+                  fence ? "_" : "",
+                  sync_status_str(status));
+       if (pt->status) {
+               struct timeval tv = ktime_to_timeval(pt->timestamp);
+               seq_printf(s, "@%ld.%06ld", tv.tv_sec, tv.tv_usec);
+       }
+
+       if (pt->parent->ops->print_pt) {
+               seq_printf(s, ": ");
+               pt->parent->ops->print_pt(s, pt);
+       }
+
+       seq_printf(s, "\n");
+}
+
+static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
+{
+       struct list_head *pos;
+       unsigned long flags;
+
+       seq_printf(s, "%s %s", obj->name, obj->ops->driver_name);
+
+       if (obj->ops->print_obj) {
+               seq_printf(s, ": ");
+               obj->ops->print_obj(s, obj);
+       }
+
+       seq_printf(s, "\n");
+
+       spin_lock_irqsave(&obj->child_list_lock, flags);
+       list_for_each(pos, &obj->child_list_head) {
+               struct sync_pt *pt =
+                       container_of(pos, struct sync_pt, child_list);
+               sync_print_pt(s, pt, false);
+       }
+       spin_unlock_irqrestore(&obj->child_list_lock, flags);
+}
+
+static void sync_print_fence(struct seq_file *s, struct sync_fence *fence)
+{
+       struct list_head *pos;
+       unsigned long flags;
+
+       seq_printf(s, "%s: %s\n", fence->name, sync_status_str(fence->status));
+
+       list_for_each(pos, &fence->pt_list_head) {
+               struct sync_pt *pt =
+                       container_of(pos, struct sync_pt, pt_list);
+               sync_print_pt(s, pt, true);
+       }
+
+       spin_lock_irqsave(&fence->waiter_list_lock, flags);
+       list_for_each(pos, &fence->waiter_list_head) {
+               struct sync_fence_waiter *waiter =
+                       container_of(pos, struct sync_fence_waiter,
+                                    waiter_list);
+
+               seq_printf(s, "waiter %pF %p\n", waiter->callback,
+                          waiter->callback_data);
+       }
+       spin_unlock_irqrestore(&fence->waiter_list_lock, flags);
+}
+
+static int sync_debugfs_show(struct seq_file *s, void *unused)
+{
+       unsigned long flags;
+       struct list_head *pos;
+
+       seq_printf(s, "objs:\n--------------\n");
+
+       spin_lock_irqsave(&sync_timeline_list_lock, flags);
+       list_for_each(pos, &sync_timeline_list_head) {
+               struct sync_timeline *obj =
+                       container_of(pos, struct sync_timeline,
+                                    sync_timeline_list);
+
+               sync_print_obj(s, obj);
+               seq_printf(s, "\n");
+       }
+       spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
+
+       seq_printf(s, "fences:\n--------------\n");
+
+       spin_lock_irqsave(&sync_fence_list_lock, flags);
+       list_for_each(pos, &sync_fence_list_head) {
+               struct sync_fence *fence =
+                       container_of(pos, struct sync_fence, sync_fence_list);
+
+               sync_print_fence(s, fence);
+               seq_printf(s, "\n");
+       }
+       spin_unlock_irqrestore(&sync_fence_list_lock, flags);
+       return 0;
+}
+
+static int sync_debugfs_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, sync_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations sync_debugfs_fops = {
+       .open           = sync_debugfs_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
+static __init int sync_debugfs_init(void)
+{
+       debugfs_create_file("sync", S_IRUGO, NULL, NULL, &sync_debugfs_fops);
+       return 0;
+}
+
+late_initcall(sync_debugfs_init);
+
+#endif

diff --git a/include/linux/sync.h b/include/linux/sync.h
index a8e289d..d64271b 100644 (file)
--- a/include/linux/sync.h
+++ b/include/linux/sync.h
@@ -39,6 +39,10 @@ struct sync_fence;
  *                      -1 if a will signabl before b
  * @free_pt:           called before sync_pt is freed
  * @release_obj:       called before sync_timeline is freed
+ * @print_obj:         print aditional debug information about sync_timeline.
+ *                       should not print a newline
+ * @print_pt:          print aditional debug information about sync_pt.
+ *                       should not print a newline
  */
 struct sync_timeline_ops {
        const char *driver_name;
@@ -57,6 +61,13 @@ struct sync_timeline_ops {
 
        /* optional */
        void (*release_obj)(struct sync_timeline *sync_timeline);
+
+       /* optional */
+       void (*print_obj)(struct seq_file *s,
+                         struct sync_timeline *sync_timeline);
+
+       /* optional */
+       void (*print_pt)(struct seq_file *s, struct sync_pt *sync_pt);
 };
 
 /**
@@ -68,6 +79,7 @@ struct sync_timeline_ops {
  * @child_list_lock:   lock protecting @child_list_head, destroyed, and
  *                       sync_pt.status
  * @active_list_head:  list of active (unsignaled/errored) sync_pts
+ * @sync_timeline_list:        membership in global sync_timeline_list
  */
 struct sync_timeline {
        const struct sync_timeline_ops  *ops;
@@ -81,6 +93,8 @@ struct sync_timeline {
 
        struct list_head        active_list_head;
        spinlock_t              active_list_lock;
+
+       struct list_head        sync_timeline_list;
 };
 
 /**
@@ -120,6 +134,7 @@ struct sync_pt {
  * @status:            1: signaled, 0:active, <0: error
  *
  * @wq:                        wait queue for fence signaling
+ * @sync_fence_list:   membership in global fence list
  */
 struct sync_fence {
        struct file             *file;
@@ -133,6 +148,8 @@ struct sync_fence {
        int                     status;
 
        wait_queue_head_t       wq;
+
+       struct list_head        sync_fence_list;
 };
 
 /**
@@ -281,9 +298,6 @@ int sync_fence_wait_async(struct sync_fence *fence,
  */
 int sync_fence_wait(struct sync_fence *fence, long timeout);
 
-/* useful for sync driver's debug print handlers */
-const char *sync_status_str(int status);
-
 #endif /* __KERNEL__ */
 
 /**