drm/i915: Pull the unconditional GPU cache invalidation into request construction

As the request will, in the following patch, implicitly invoke a
context-switch on construction, we should precede that with a GPU TLB
invalidation. Also, even before using GGTT, we always want to invalidate
the TLBs for any updates (as well as the ppgtt invalidates that are
unconditionally applied by execbuf). Since we almost always require the
TLB invalidate, do it unconditionally on request allocation and so we can
remove it from all other paths.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171120102002.22254-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 53ccb27bfe91776e404d724a2e3f3b7c03c45fbc..b7895788bc752571c7986e23db5981ebde71594e 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1111,10 +1111,6 @@ static int __reloc_gpu_alloc(struct i915_execbuffer *eb,
        if (err)
                goto err_request;
 
-       err = eb->engine->emit_flush(rq, EMIT_INVALIDATE);
-       if (err)
-               goto err_request;
-
        err = i915_switch_context(rq);
        if (err)
                goto err_request;
@@ -1818,8 +1814,7 @@ static int eb_move_to_gpu(struct i915_execbuffer *eb)
        /* Unconditionally flush any chipset caches (for streaming writes). */
        i915_gem_chipset_flush(eb->i915);
 
-       /* Unconditionally invalidate GPU caches and TLBs. */
-       return eb->engine->emit_flush(eb->request, EMIT_INVALIDATE);
+       return 0;
 }
 
 static bool i915_gem_check_execbuffer(struct drm_i915_gem_execbuffer2 *exec)

diff --git a/drivers/gpu/drm/i915/i915_gem_render_state.c b/drivers/gpu/drm/i915/i915_gem_render_state.c
index c2723a06fbb4e2eec80a5e137ac03590860c4f40..f7fc0df251acf24943a757c2be1be3c81e7fa95e 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_render_state.c
+++ b/drivers/gpu/drm/i915/i915_gem_render_state.c
@@ -208,10 +208,6 @@ int i915_gem_render_state_emit(struct drm_i915_gem_request *rq)
        if (err)
                goto err_unpin;
 
-       err = engine->emit_flush(rq, EMIT_INVALIDATE);
-       if (err)
-               goto err_unpin;
-
        err = engine->emit_bb_start(rq,
                                    so.batch_offset, so.batch_size,
                                    I915_DISPATCH_SECURE);

diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c
index e0d6221022a83ac9a159e72e7a8537c6334d12a5..91eae1b20c42826bcd747fcd99c01ae1fc2da653 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/i915_gem_request.c
@@ -703,17 +703,31 @@ i915_gem_request_alloc(struct intel_engine_cs *engine,
        req->reserved_space = MIN_SPACE_FOR_ADD_REQUEST;
        GEM_BUG_ON(req->reserved_space < engine->emit_breadcrumb_sz);
 
-       ret = engine->request_alloc(req);
-       if (ret)
-               goto err_ctx;
-
-       /* Record the position of the start of the request so that
+       /*
+        * Record the position of the start of the request so that
         * should we detect the updated seqno part-way through the
         * GPU processing the request, we never over-estimate the
         * position of the head.
         */
        req->head = req->ring->emit;
 
+       /* Unconditionally invalidate GPU caches and TLBs. */
+       ret = engine->emit_flush(req, EMIT_INVALIDATE);
+       if (ret)
+               goto err_ctx;
+
+       ret = engine->request_alloc(req);
+       if (ret) {
+               /*
+                * Past the point-of-no-return. Since we may have updated
+                * global state after partially completing the request alloc,
+                * we need to commit any commands so far emitted in the
+                * request to the HW.
+                */
+               __i915_add_request(req, false);
+               return ERR_PTR(ret);
+       }
+
        /* Check that we didn't interrupt ourselves with a new request */
        GEM_BUG_ON(req->timeline->seqno != req->fence.seqno);
        return req;

diff --git a/drivers/gpu/drm/i915/selftests/huge_pages.c b/drivers/gpu/drm/i915/selftests/huge_pages.c
index 01af540b6ef9a8a070f3a05d8a419a0d0dddede2..159a2cb6876583c8e48896eec8cbf195e1043c7b 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/huge_pages.c
+++ b/drivers/gpu/drm/i915/selftests/huge_pages.c
@@ -989,10 +989,6 @@ static int gpu_write(struct i915_vma *vma,
        i915_vma_unpin(batch);
        i915_vma_close(batch);
 
-       err = rq->engine->emit_flush(rq, EMIT_INVALIDATE);
-       if (err)
-               goto err_request;
-
        err = i915_switch_context(rq);
        if (err)
                goto err_request;

diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_context.c b/drivers/gpu/drm/i915/selftests/i915_gem_context.c
index c82780a9d455652e1b06bfae0635b711fcb90935..4ff30b9af1fec0b4cd0a7aac0b737e9aa4dba2a9 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_context.c
@@ -158,10 +158,6 @@ static int gpu_fill(struct drm_i915_gem_object *obj,
                goto err_batch;
        }
 
-       err = engine->emit_flush(rq, EMIT_INVALIDATE);
-       if (err)
-               goto err_request;
-
        err = i915_switch_context(rq);
        if (err)
                goto err_request;

diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_request.c b/drivers/gpu/drm/i915/selftests/i915_gem_request.c
index 6bce99050e947ad52fe24110f7fdf579c073b79c..d7bf53ff8f84ed39d11b7c5c09a81ab25f2a0803 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_request.c
@@ -459,10 +459,6 @@ empty_request(struct intel_engine_cs *engine,
        if (IS_ERR(request))
                return request;
 
-       err = engine->emit_flush(request, EMIT_INVALIDATE);
-       if (err)
-               goto out_request;
-
        err = i915_switch_context(request);
        if (err)
                goto out_request;
@@ -675,9 +671,6 @@ static int live_all_engines(void *arg)
                        goto out_request;
                }
 
-               err = engine->emit_flush(request[id], EMIT_INVALIDATE);
-               GEM_BUG_ON(err);
-
                err = i915_switch_context(request[id]);
                GEM_BUG_ON(err);
 
@@ -797,9 +790,6 @@ static int live_sequential_engines(void *arg)
                        }
                }
 
-               err = engine->emit_flush(request[id], EMIT_INVALIDATE);
-               GEM_BUG_ON(err);
-
                err = i915_switch_context(request[id]);
                GEM_BUG_ON(err);
 

diff --git a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
index 71ce06680d66ad0db52c194d163315faaaa7ef7d..145bdc26553c0880f4ca281a44d6aae1a04b9d9c 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
+++ b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
@@ -114,10 +114,6 @@ static int emit_recurse_batch(struct hang *h,
        if (err)
                goto unpin_vma;
 
-       err = rq->engine->emit_flush(rq, EMIT_INVALIDATE);
-       if (err)
-               goto unpin_hws;
-
        err = i915_switch_context(rq);
        if (err)
                goto unpin_hws;