drm/i915: Use ww locking in intel_renderstate.

We want to start using ww locking in intel_context_pin, for this
we need to lock multiple objects, and the single i915_gem_object_lock
is not enough.

Convert to using ww-waiting, and make sure we always pin intel_context_state,
even if we don't have a renderstate object.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200819140904.1708856-10-maarten.lankhorst@linux.intel.com
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index e0755f1a904b283bbf79c2de04136ecb9d3d0890..8694ddbdac4cc30f45b8ac15a31ecf8ad172efd4 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -406,21 +406,20 @@ static int __engines_record_defaults(struct intel_gt *gt)
                /* We must be able to switch to something! */
                GEM_BUG_ON(!engine->kernel_context);
 
-               err = intel_renderstate_init(&so, engine);
-               if (err)
-                       goto out;
-
                ce = intel_context_create(engine);
                if (IS_ERR(ce)) {
                        err = PTR_ERR(ce);
                        goto out;
                }
 
-               rq = intel_context_create_request(ce);
+               err = intel_renderstate_init(&so, ce);
+               if (err)
+                       goto err;
+
+               rq = i915_request_create(ce);
                if (IS_ERR(rq)) {
                        err = PTR_ERR(rq);
-                       intel_context_put(ce);
-                       goto out;
+                       goto err_fini;
                }
 
                err = intel_engine_emit_ctx_wa(rq);
@@ -434,9 +433,13 @@ static int __engines_record_defaults(struct intel_gt *gt)
 err_rq:
                requests[id] = i915_request_get(rq);
                i915_request_add(rq);
-               intel_renderstate_fini(&so);
-               if (err)
+err_fini:
+               intel_renderstate_fini(&so, ce);
+err:
+               if (err) {
+                       intel_context_put(ce);
                        goto out;
+               }
        }
 
        /* Flush the default context image to memory, and enable powersaving. */

diff --git a/drivers/gpu/drm/i915/gt/intel_renderstate.c b/drivers/gpu/drm/i915/gt/intel_renderstate.c
index 1bfad589c63b348d53b35943302ff3bf0c9f2c98..5164de04049d2948771e3df2801cf7393750d7e4 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_renderstate.c
+++ b/drivers/gpu/drm/i915/gt/intel_renderstate.c
@@ -27,6 +27,7 @@
 
 #include "i915_drv.h"
 #include "intel_renderstate.h"
+#include "gt/intel_context.h"
 #include "intel_ring.h"
 
 static const struct intel_renderstate_rodata *
@@ -157,33 +158,47 @@ out:
 #undef OUT_BATCH
 
 int intel_renderstate_init(struct intel_renderstate *so,
-                          struct intel_engine_cs *engine)
+                          struct intel_context *ce)
 {
-       struct drm_i915_gem_object *obj;
+       struct intel_engine_cs *engine = ce->engine;
+       struct drm_i915_gem_object *obj = NULL;
        int err;
 
        memset(so, 0, sizeof(*so));
 
        so->rodata = render_state_get_rodata(engine);
-       if (!so->rodata)
-               return 0;
+       if (so->rodata) {
+               if (so->rodata->batch_items * 4 > PAGE_SIZE)
+                       return -EINVAL;
+
+               obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);
+               if (IS_ERR(obj))
+                       return PTR_ERR(obj);
+
+               so->vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
+               if (IS_ERR(so->vma)) {
+                       err = PTR_ERR(so->vma);
+                       goto err_obj;
+               }
+       }
 
-       if (so->rodata->batch_items * 4 > PAGE_SIZE)
-               return -EINVAL;
+       i915_gem_ww_ctx_init(&so->ww, true);
+retry:
+       err = intel_context_pin(ce);
+       if (err)
+               goto err_fini;
 
-       obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);
-       if (IS_ERR(obj))
-               return PTR_ERR(obj);
+       /* return early if there's nothing to setup */
+       if (!err && !so->rodata)
+               return 0;
 
-       so->vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
-       if (IS_ERR(so->vma)) {
-               err = PTR_ERR(so->vma);
-               goto err_obj;
-       }
+       err = i915_gem_object_lock(so->vma->obj, &so->ww);
+       if (err)
+               goto err_context;
 
        err = i915_vma_pin(so->vma, 0, 0, PIN_GLOBAL | PIN_HIGH);
        if (err)
-               goto err_obj;
+               goto err_context;
 
        err = render_state_setup(so, engine->i915);
        if (err)
@@ -193,8 +208,18 @@ int intel_renderstate_init(struct intel_renderstate *so,
 
 err_unpin:
        i915_vma_unpin(so->vma);
+err_context:
+       intel_context_unpin(ce);
+err_fini:
+       if (err == -EDEADLK) {
+               err = i915_gem_ww_ctx_backoff(&so->ww);
+               if (!err)
+                       goto retry;
+       }
+       i915_gem_ww_ctx_fini(&so->ww);
 err_obj:
-       i915_gem_object_put(obj);
+       if (obj)
+               i915_gem_object_put(obj);
        so->vma = NULL;
        return err;
 }
@@ -208,11 +233,9 @@ int intel_renderstate_emit(struct intel_renderstate *so,
        if (!so->vma)
                return 0;
 
-       i915_vma_lock(so->vma);
        err = i915_request_await_object(rq, so->vma->obj, false);
        if (err == 0)
                err = i915_vma_move_to_active(so->vma, rq, 0);
-       i915_vma_unlock(so->vma);
        if (err)
                return err;
 
@@ -233,7 +256,17 @@ int intel_renderstate_emit(struct intel_renderstate *so,
        return 0;
 }
 
-void intel_renderstate_fini(struct intel_renderstate *so)
+void intel_renderstate_fini(struct intel_renderstate *so,
+                           struct intel_context *ce)
 {
-       i915_vma_unpin_and_release(&so->vma, 0);
+       if (so->vma) {
+               i915_vma_unpin(so->vma);
+               i915_vma_close(so->vma);
+       }
+
+       intel_context_unpin(ce);
+       i915_gem_ww_ctx_fini(&so->ww);
+
+       if (so->vma)
+               i915_gem_object_put(so->vma->obj);
 }

diff --git a/drivers/gpu/drm/i915/gt/intel_renderstate.h b/drivers/gpu/drm/i915/gt/intel_renderstate.h
index 5700be69a05a65dc97bebf7a6928208cd987ae95..713aa1e86c80be75a464db4ea96df1bde07dd584 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_renderstate.h
+++ b/drivers/gpu/drm/i915/gt/intel_renderstate.h
@@ -25,9 +25,10 @@
 #define _INTEL_RENDERSTATE_H_
 
 #include <linux/types.h>
+#include "i915_gem.h"
 
 struct i915_request;
-struct intel_engine_cs;
+struct intel_context;
 struct i915_vma;
 
 struct intel_renderstate_rodata {
@@ -49,6 +50,7 @@ extern const struct intel_renderstate_rodata gen8_null_state;
 extern const struct intel_renderstate_rodata gen9_null_state;
 
 struct intel_renderstate {
+       struct i915_gem_ww_ctx ww;
        const struct intel_renderstate_rodata *rodata;
        struct i915_vma *vma;
        u32 batch_offset;
@@ -58,9 +60,10 @@ struct intel_renderstate {
 };
 
 int intel_renderstate_init(struct intel_renderstate *so,
-                          struct intel_engine_cs *engine);
+                          struct intel_context *ce);
 int intel_renderstate_emit(struct intel_renderstate *so,
                           struct i915_request *rq);
-void intel_renderstate_fini(struct intel_renderstate *so);
+void intel_renderstate_fini(struct intel_renderstate *so,
+                           struct intel_context *ce);
 
 #endif /* _INTEL_RENDERSTATE_H_ */