[Intel-gfx] [PATCH v6 26/64] drm/i915: Make lrc_init_wa_ctx compatible with ww locking.

[Maarten Lankhorst]

Make creation separate from pinning, in order to take the lock only
once, and pin the mapping with the lock held.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
---
 drivers/gpu/drm/i915/gt/intel_lrc.c | 32 ++++++++++++++++++++++-------
 1 file changed, 25 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 4e856947fb13..707981db189b 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -1422,7 +1422,7 @@ gen10_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
 
 #define CTX_WA_BB_SIZE (PAGE_SIZE)
 
-static int lrc_setup_wa_ctx(struct intel_engine_cs *engine)
+static int lrc_create_wa_ctx(struct intel_engine_cs *engine)
 {
 	struct drm_i915_gem_object *obj;
 	struct i915_vma *vma;
@@ -1438,10 +1438,6 @@ static int lrc_setup_wa_ctx(struct intel_engine_cs *engine)
 		goto err;
 	}
 
-	err = i915_ggtt_pin(vma, NULL, 0, PIN_HIGH);
-	if (err)
-		goto err;
-
 	engine->wa_ctx.vma = vma;
 	return 0;
 
@@ -1464,6 +1460,7 @@ int lrc_init_wa_ctx(struct intel_engine_cs *engine)
 		&wa_ctx->indirect_ctx, &wa_ctx->per_ctx
 	};
 	wa_bb_func_t wa_bb_fn[ARRAY_SIZE(wa_bb)];
+	struct i915_gem_ww_ctx ww;
 	void *batch, *batch_ptr;
 	unsigned int i;
 	int ret;
@@ -1492,13 +1489,21 @@ int lrc_init_wa_ctx(struct intel_engine_cs *engine)
 		return 0;
 	}
 
-	ret = lrc_setup_wa_ctx(engine);
+	ret = lrc_create_wa_ctx(engine);
 	if (ret) {
 		drm_dbg(&engine->i915->drm,
 			"Failed to setup context WA page: %d\n", ret);
 		return ret;
 	}
 
+	i915_gem_ww_ctx_init(&ww, true);
+retry:
+	ret = i915_gem_object_lock(wa_ctx->vma->obj, &ww);
+	if (!ret)
+		ret = i915_ggtt_pin(wa_ctx->vma, &ww, 0, PIN_HIGH);
+	if (ret)
+		goto err;
+
 	batch = i915_gem_object_pin_map(wa_ctx->vma->obj, I915_MAP_WB);
 
 	/*
@@ -1522,8 +1527,21 @@ int lrc_init_wa_ctx(struct intel_engine_cs *engine)
 
 	__i915_gem_object_flush_map(wa_ctx->vma->obj, 0, batch_ptr - batch);
 	__i915_gem_object_release_map(wa_ctx->vma->obj);
+
 	if (ret)
-		lrc_fini_wa_ctx(engine);
+		i915_vma_unpin(wa_ctx->vma);
+err:
+	if (ret == -EDEADLK) {
+		ret = i915_gem_ww_ctx_backoff(&ww);
+		if (!ret)
+			goto retry;
+	}
+	i915_gem_ww_ctx_fini(&ww);
+
+	if (ret && engine->wa_ctx.vma) {
+		i915_vma_put(engine->wa_ctx.vma);
+		engine->wa_ctx.vma = NULL;
+	}
 
 	return ret;
 }
-- 
2.30.0.rc1