[intel-gem] Replace idlelock usage with real lock acquisition.

diff --git a/linux-core/drmP.h b/linux-core/drmP.h
index fc7043d..8246f44 100644 (file)
--- a/linux-core/drmP.h
+++ b/linux-core/drmP.h
@@ -474,6 +474,11 @@ struct drm_lock_data {
        uint32_t kernel_waiters;
        uint32_t user_waiters;
        int idle_has_lock;
+       /**
+        * Boolean signaling that the lock is held on behalf of the
+        * file_priv client by the kernel in an ioctl handler.
+        */
+       int kernel_held;
 };
 
 /**
@@ -778,6 +783,7 @@ struct drm_driver {
         * Driver-specific callback to set memory domains from userspace
         */
        int (*gem_set_domain) (struct drm_gem_object *obj,
+                              struct drm_file *file_priv,
                               uint32_t read_domains,
                               uint32_t write_domain);
 
@@ -1178,6 +1184,9 @@ extern int drm_lock_take(struct drm_lock_data *lock_data, unsigned int context);
 extern int drm_lock_free(struct drm_lock_data *lock_data, unsigned int context);
 extern void drm_idlelock_take(struct drm_lock_data *lock_data);
 extern void drm_idlelock_release(struct drm_lock_data *lock_data);
+extern int drm_client_lock_take(struct drm_device *dev,
+                               struct drm_file *file_priv);
+extern void drm_client_lock_release(struct drm_device *dev);
 
 /*
  * These are exported to drivers so that they can implement fencing using

diff --git a/linux-core/drm_gem.c b/linux-core/drm_gem.c
index fb175d7..b726e59 100644 (file)
--- a/linux-core/drm_gem.c
+++ b/linux-core/drm_gem.c
@@ -291,7 +291,7 @@ drm_gem_pread_ioctl(struct drm_device *dev, void *data,
 
        mutex_lock(&dev->struct_mutex);
        if (dev->driver->gem_set_domain) {
-               ret = dev->driver->gem_set_domain(obj,
+               ret = dev->driver->gem_set_domain(obj, file_priv,
                                                  DRM_GEM_DOMAIN_CPU,
                                                  0);
                if (ret) {
@@ -384,7 +384,7 @@ drm_gem_pwrite_ioctl(struct drm_device *dev, void *data,
 
        mutex_lock(&dev->struct_mutex);
        if (dev->driver->gem_set_domain) {
-               ret = dev->driver->gem_set_domain(obj,
+               ret = dev->driver->gem_set_domain(obj, file_priv,
                                                  DRM_GEM_DOMAIN_CPU,
                                                  DRM_GEM_DOMAIN_CPU);
                if (ret) {
@@ -530,7 +530,7 @@ drm_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 
        mutex_lock(&dev->struct_mutex);
        if (dev->driver->gem_set_domain) {
-               ret = dev->driver->gem_set_domain(obj,
+               ret = dev->driver->gem_set_domain(obj, file_priv,
                                                   args->read_domains,
                                                   args->write_domain);
        } else {

diff --git a/linux-core/drm_lock.c b/linux-core/drm_lock.c
index db1d646..ad7c167 100644 (file)
--- a/linux-core/drm_lock.c
+++ b/linux-core/drm_lock.c
@@ -215,22 +215,16 @@ int drm_lock_take(struct drm_lock_data *lock_data,
        } while (prev != old);
        spin_unlock_irqrestore(&lock_data->spinlock, irqflags);
 
-       if (_DRM_LOCKING_CONTEXT(old) == context) {
-               if (old & _DRM_LOCK_HELD) {
-                       if (context != DRM_KERNEL_CONTEXT) {
-                               DRM_ERROR("%d holds heavyweight lock\n",
-                                         context);
-                       }
-                       return 0;
+       /* Warn on recursive locking of user contexts. */
+       if (_DRM_LOCKING_CONTEXT(old) == context && _DRM_LOCK_IS_HELD(old)) {
+               if (context != DRM_KERNEL_CONTEXT) {
+                       DRM_ERROR("%d holds heavyweight lock\n",
+                                 context);
                }
+               return 0;
        }
 
-       if ((_DRM_LOCKING_CONTEXT(new)) == context && (new & _DRM_LOCK_HELD)) {
-               /* Have lock */
-
-               return 1;
-       }
-       return 0;
+       return !_DRM_LOCK_IS_HELD(old);
 }
 
 /**
@@ -386,6 +380,60 @@ void drm_idlelock_release(struct drm_lock_data *lock_data)
 }
 EXPORT_SYMBOL(drm_idlelock_release);
 
+/**
+ * Takes the lock on behalf of the client if needed, using the kernel context.
+ *
+ * This allows us to hide the hardware lock when it's required for protection
+ * of data structures (such as command ringbuffer) shared with the X Server, and
+ * a way for us to transition to lockless for those requests when the X Server
+ * stops accessing the ringbuffer directly, without having to update the
+ * other userland clients.
+ */
+int drm_client_lock_take(struct drm_device *dev, struct drm_file *file_priv)
+{
+       int ret;
+       unsigned long irqflags;
+
+       /* If the client has the lock, we're already done. */
+       if (drm_i_have_hw_lock(dev, file_priv))
+               return 0;
+
+       /* Client doesn't hold the lock.  Block taking the lock with the kernel
+        * context on behalf of the client, and return whether we were
+        * successful.
+        */
+       spin_lock_irqsave(&dev->lock.spinlock, irqflags);
+       dev->lock.user_waiters++;
+       spin_unlock_irqrestore(&dev->lock.spinlock, irqflags);
+       ret = wait_event_interruptible(dev->lock.lock_queue,
+                                      drm_lock_take(&dev->lock,
+                                                    DRM_KERNEL_CONTEXT));
+       spin_lock_irqsave(&dev->lock.spinlock, irqflags);
+       dev->lock.user_waiters--;
+       if (ret != 0) {
+               spin_unlock_irqrestore(&dev->lock.spinlock, irqflags);
+               return ret;
+       } else {
+               dev->lock.file_priv = file_priv;
+               dev->lock.lock_time = jiffies;
+               dev->lock.kernel_held = 1;
+               file_priv->lock_count++;
+               spin_unlock_irqrestore(&dev->lock.spinlock, irqflags);
+               return 0;
+       }
+}
+EXPORT_SYMBOL(drm_client_lock_take);
+
+void drm_client_lock_release(struct drm_device *dev)
+{
+       if (dev->lock.kernel_held) {
+               dev->lock.kernel_held = 0;
+               dev->lock.file_priv = NULL;
+               drm_lock_free(&dev->lock, DRM_KERNEL_CONTEXT);
+       }
+}
+EXPORT_SYMBOL(drm_client_lock_release);
+
 
 int drm_i_have_hw_lock(struct drm_device *dev, struct drm_file *file_priv)
 {

diff --git a/linux-core/i915_gem.c b/linux-core/i915_gem.c
index 5eeabda..ebe5153 100644 (file)
--- a/linux-core/i915_gem.c
+++ b/linux-core/i915_gem.c
@@ -1522,6 +1522,7 @@ void i915_gem_free_object(struct drm_gem_object *obj)
 
 int
 i915_gem_set_domain(struct drm_gem_object *obj,
+                   struct drm_file *file_priv,
                    uint32_t read_domains,
                    uint32_t write_domain)
 {
@@ -1529,11 +1530,11 @@ i915_gem_set_domain(struct drm_gem_object *obj,
 
        BUG_ON(!mutex_is_locked(&dev->struct_mutex));
 
-       drm_idlelock_take (&dev->lock);
+       drm_client_lock_take(dev, file_priv);
        i915_kernel_lost_context(dev);
        i915_gem_object_set_domain(obj, read_domains, write_domain);
        i915_gem_dev_set_domain(obj->dev);
-       drm_idlelock_release (&dev->lock);
+       drm_client_lock_release(dev);
 
        return 0;
 }

diff --git a/shared-core/i915_drv.h b/shared-core/i915_drv.h
index fee6d43..76bc6be 100644 (file)
--- a/shared-core/i915_drv.h
+++ b/shared-core/i915_drv.h
@@ -454,6 +454,7 @@ int i915_gem_busy_ioctl(struct drm_device *dev, void *data,
 int i915_gem_init_object(struct drm_gem_object *obj);
 void i915_gem_free_object(struct drm_gem_object *obj);
 int i915_gem_set_domain(struct drm_gem_object *obj,
+                       struct drm_file *file_priv,
                        uint32_t read_domains,
                        uint32_t write_domain);
 int i915_gem_flush_pwrite(struct drm_gem_object *obj,