[RFC PATCH 035/162] drm/i915: Make intel_init_workaround_bb more compatible with ww locking.

[Matthew Auld]

From: Daniele Ceraolo Spurio <daniele.ceraolospu...@intel.com>

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.lankho...@linux.intel.com>
Cc: Thomas Hellström <thomas.hellst...@linux.intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospu...@intel.com>
---
 .../drm/i915/gt/intel_engine_workaround_bb.c  | 45 +++++++++++++++----
 1 file changed, 37 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_workaround_bb.c 
b/drivers/gpu/drm/i915/gt/intel_engine_workaround_bb.c
index b03bdfc92bb2..f3636b73cc10 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_workaround_bb.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_workaround_bb.c
@@ -229,7 +229,7 @@ gen10_init_indirectctx_bb(struct intel_engine_cs *engine, 
u32 *batch)
 
 #define CTX_WA_BB_OBJ_SIZE (PAGE_SIZE)
 
-static int lrc_setup_wa_ctx(struct intel_engine_cs *engine)
+static int lrc_init_wa_ctx(struct intel_engine_cs *engine)
 {
        struct drm_i915_gem_object *obj;
        struct i915_vma *vma;
@@ -245,10 +245,6 @@ 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;
 
@@ -257,6 +253,18 @@ static int lrc_setup_wa_ctx(struct intel_engine_cs *engine)
        return err;
 }
 
+static void lrc_destroy_wa_ctx(struct intel_engine_cs *engine, bool unpin)
+{
+       if (!engine->wa_ctx.vma)
+               return;
+
+       if (unpin)
+               i915_vma_unpin(engine->wa_ctx.vma);
+
+       i915_vma_put(engine->wa_ctx.vma);
+       engine->wa_ctx.vma = NULL;
+}
+
 typedef u32 *(*wa_bb_func_t)(struct intel_engine_cs *engine, u32 *batch);
 
 int intel_init_workaround_bb(struct intel_engine_cs *engine)
@@ -266,6 +274,7 @@ int intel_init_workaround_bb(struct intel_engine_cs *engine)
                                            &wa_ctx->per_ctx };
        wa_bb_func_t wa_bb_fn[2];
        void *batch, *batch_ptr;
+       struct i915_gem_ww_ctx ww;
        unsigned int i;
        int ret;
 
@@ -293,13 +302,21 @@ int intel_init_workaround_bb(struct intel_engine_cs 
*engine)
                return 0;
        }
 
-       ret = lrc_setup_wa_ctx(engine);
+       ret = lrc_init_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);
 
        /*
@@ -323,13 +340,25 @@ int intel_init_workaround_bb(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)
+               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)
-               intel_fini_workaround_bb(engine);
+               lrc_destroy_wa_ctx(engine, false);
 
        return ret;
 }
 
+
 void intel_fini_workaround_bb(struct intel_engine_cs *engine)
 {
-       i915_vma_unpin_and_release(&engine->wa_ctx.vma, 0);
+       lrc_destroy_wa_ctx(engine, true);
 }
-- 
2.26.2

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel