drm/i915/gem: Optimistically prune dma-resv from the shrinker.

As we shrink an object, also see if we can prune the dma-resv of idle
fences it is maintaining a reference to.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201223122051.4624-2-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 849c7b3..e3684d6 100644 (file)
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -58,6 +58,7 @@ i915-y += i915_drv.o \
 
 # core library code
 i915-y += \
+       dma_resv_utils.o \
        i915_memcpy.o \
        i915_mm.o \
        i915_sw_fence.o \

diff --git a/drivers/gpu/drm/i915/dma_resv_utils.c b/drivers/gpu/drm/i915/dma_resv_utils.c
new file mode 100644 (file)
index 0000000..9e508e7
--- /dev/null
+++ b/drivers/gpu/drm/i915/dma_resv_utils.c
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2020 Intel Corporation
+ */
+
+#include <linux/dma-resv.h>
+
+#include "dma_resv_utils.h"
+
+void dma_resv_prune(struct dma_resv *resv)
+{
+       if (dma_resv_trylock(resv)) {
+               if (dma_resv_test_signaled_rcu(resv, true))
+                       dma_resv_add_excl_fence(resv, NULL);
+               dma_resv_unlock(resv);
+       }
+}

diff --git a/drivers/gpu/drm/i915/dma_resv_utils.h b/drivers/gpu/drm/i915/dma_resv_utils.h
new file mode 100644 (file)
index 0000000..b9d8fb5
--- /dev/null
+++ b/drivers/gpu/drm/i915/dma_resv_utils.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2020 Intel Corporation
+ */
+
+#ifndef DMA_RESV_UTILS_H
+#define DMA_RESV_UTILS_H
+
+struct dma_resv;
+
+void dma_resv_prune(struct dma_resv *resv);
+
+#endif /* DMA_RESV_UTILS_H */

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
index dc8f052..c2dba1c 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
@@ -15,6 +15,7 @@
 
 #include "gt/intel_gt_requests.h"
 
+#include "dma_resv_utils.h"
 #include "i915_trace.h"
 
 static bool swap_available(void)
@@ -209,6 +210,8 @@ i915_gem_shrink(struct drm_i915_private *i915,
                                mutex_unlock(&obj->mm.lock);
                        }
 
+                       dma_resv_prune(obj->base.resv);
+
                        scanned += obj->base.size >> PAGE_SHIFT;
                        i915_gem_object_put(obj);
 

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_wait.c b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
index 8af55cd..c1b13ac 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_wait.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
@@ -9,6 +9,7 @@
 
 #include "gt/intel_engine.h"
 
+#include "dma_resv_utils.h"
 #include "i915_gem_ioctls.h"
 #include "i915_gem_object.h"
 
@@ -84,11 +85,8 @@ i915_gem_object_wait_reservation(struct dma_resv *resv,
         * Opportunistically prune the fences iff we know they have *all* been
         * signaled.
         */
-       if (prune_fences && dma_resv_trylock(resv)) {
-               if (dma_resv_test_signaled_rcu(resv, true))
-                       dma_resv_add_excl_fence(resv, NULL);
-               dma_resv_unlock(resv);
-       }
+       if (prune_fences)
+               dma_resv_prune(resv);
 
        return timeout;
 }