[Mesa-dev] [PATCH v2 1/2] anv: Use GEM_BUSY instead of GEM_WAIT when timeout == 0

[Jason Ekstrand]

---
 src/intel/vulkan/anv_device.c  | 26 +++++++++++++++++++-------
 src/intel/vulkan/anv_gem.c     | 17 +++++++++++++++++
 src/intel/vulkan/anv_private.h |  1 +
 3 files changed, 37 insertions(+), 7 deletions(-)

diff --git a/src/intel/vulkan/anv_device.c b/src/intel/vulkan/anv_device.c
index 9e860d5..fc3c27e 100644
--- a/src/intel/vulkan/anv_device.c
+++ b/src/intel/vulkan/anv_device.c
@@ -1294,13 +1294,25 @@ VkResult
 anv_device_wait(struct anv_device *device, struct anv_bo *bo,
                 int64_t timeout)
 {
-   int ret = anv_gem_wait(device, bo->gem_handle, &timeout);
-   if (ret == -1 && errno == ETIME) {
-      return VK_TIMEOUT;
-   } else if (ret == -1) {
-      /* We don't know the real error. */
-      device->lost = true;
-      return vk_errorf(VK_ERROR_DEVICE_LOST, "gem wait failed: %m");
+   if (timeout == 0) {
+      /* GEM_BUSY is more efficient if we don't want to wait */
+      int ret = anv_gem_busy(device, bo->gem_handle);
+      if (ret == 1) {
+         return VK_TIMEOUT;
+      } else if (ret == -1) {
+         /* We don't know the real error. */
+         device->lost = true;
+         return vk_errorf(VK_ERROR_DEVICE_LOST, "gem wait failed: %m");
+      }
+   } else {
+      int ret = anv_gem_wait(device, bo->gem_handle, &timeout);
+      if (ret == -1 && errno == ETIME) {
+         return VK_TIMEOUT;
+      } else if (ret == -1) {
+         /* We don't know the real error. */
+         device->lost = true;
+         return vk_errorf(VK_ERROR_DEVICE_LOST, "gem wait failed: %m");
+      }
    }
 
    /* Query for device status after the wait.  If the BO we're waiting on got
diff --git a/src/intel/vulkan/anv_gem.c b/src/intel/vulkan/anv_gem.c
index 7612f49..86a456a 100644
--- a/src/intel/vulkan/anv_gem.c
+++ b/src/intel/vulkan/anv_gem.c
@@ -147,6 +147,23 @@ anv_gem_set_domain(struct anv_device *device, uint32_t gem_handle,
 }
 
 /**
+ * Returns 0, 1, or negative to indicate error
+ */
+int
+anv_gem_busy(struct anv_device *device, uint32_t gem_handle)
+{
+   struct drm_i915_gem_busy busy = {
+      .handle = gem_handle,
+   };
+
+   int ret = anv_ioctl(device->fd, DRM_IOCTL_I915_GEM_BUSY, &busy);
+   if (ret < 0)
+      return ret;
+
+   return busy.busy != 0;
+}
+
+/**
  * On error, \a timeout_ns holds the remaining time.
  */
 int
diff --git a/src/intel/vulkan/anv_private.h b/src/intel/vulkan/anv_private.h
index dc83b4a..2375247 100644
--- a/src/intel/vulkan/anv_private.h
+++ b/src/intel/vulkan/anv_private.h
@@ -647,6 +647,7 @@ void anv_gem_munmap(void *p, uint64_t size);
 uint32_t anv_gem_create(struct anv_device *device, size_t size);
 void anv_gem_close(struct anv_device *device, uint32_t gem_handle);
 uint32_t anv_gem_userptr(struct anv_device *device, void *mem, size_t size);
+int anv_gem_busy(struct anv_device *device, uint32_t gem_handle);
 int anv_gem_wait(struct anv_device *device, uint32_t gem_handle, int64_t *timeout_ns);
 int anv_gem_execbuffer(struct anv_device *device,
                        struct drm_i915_gem_execbuffer2 *execbuf);
-- 
2.5.0.400.gff86faf