drm/i915: Stop storing the ring size in the ring pointer (v3)

Previously, we were storing the ring size in the ring pointer before it
was actually allocated.  We would then guard setting the ring size on
checking for CONTEXT_ALLOC_BIT.  This is error-prone at best and really
only saves us a few bytes on something that already burns at least 4K.
Instead, this patch adds a new ring_size field and makes everything use
that.

v2 (Daniel Vetter):
 - Replace 512 * SZ_4K with SZ_2M

v2 (Jason Ekstrand):
 - Rebase on top of page migration code

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210708154835.528166-3-jason@jlekstrand.net

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index ddc3cc3f8f092ded5626e59ea429deecd897546f..a4faf06022d5a280e26508260d06f3906674bb32 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -211,8 +211,7 @@ static void intel_context_set_gem(struct intel_context *ce,
        GEM_BUG_ON(rcu_access_pointer(ce->gem_context));
        RCU_INIT_POINTER(ce->gem_context, ctx);
 
-       if (!test_bit(CONTEXT_ALLOC_BIT, &ce->flags))
-               ce->ring = __intel_context_ring_size(SZ_16K);
+       ce->ring_size = SZ_16K;
 
        if (rcu_access_pointer(ctx->vm)) {
                struct i915_address_space *vm;

diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index 4033184f13b9fe9474443dd5f4bf30e3631a8330..bd63813c8a802537ca609f058bde00d3849a2b19 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -371,7 +371,8 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine)
        ce->engine = engine;
        ce->ops = engine->cops;
        ce->sseu = engine->sseu;
-       ce->ring = __intel_context_ring_size(SZ_4K);
+       ce->ring = NULL;
+       ce->ring_size = SZ_4K;
 
        ewma_runtime_init(&ce->runtime.avg);
 

diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h
index f83a73a2b39fc239006413a2a90deac00247a3f6..b10cbe8fee9923f8e2a62572d2a4515d6936bb02 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_context.h
+++ b/drivers/gpu/drm/i915/gt/intel_context.h
@@ -175,11 +175,6 @@ int intel_context_prepare_remote_request(struct intel_context *ce,
 
 struct i915_request *intel_context_create_request(struct intel_context *ce);
 
-static inline struct intel_ring *__intel_context_ring_size(u64 sz)
-{
-       return u64_to_ptr(struct intel_ring, sz);
-}
-
 static inline bool intel_context_is_barrier(const struct intel_context *ce)
 {
        return test_bit(CONTEXT_BARRIER_BIT, &ce->flags);

diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h
index ed8c447a7346ba433f7f947c3713cb27d1db5d36..90026c17710553ebee56cde9bd3fb0185c9324c2 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_context_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_context_types.h
@@ -82,6 +82,7 @@ struct intel_context {
        spinlock_t signal_lock; /* protects signals, the list of requests */
 
        struct i915_vma *state;
+       u32 ring_size;
        struct intel_ring *ring;
        struct intel_timeline *timeline;
 

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 5ca3d16643353b8cf7adb47865ec175fdcd7e91a..d561573ed98c25291b6fac512c4fd71d8bacd081 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -807,7 +807,8 @@ intel_engine_create_pinned_context(struct intel_engine_cs *engine,
 
        __set_bit(CONTEXT_BARRIER_BIT, &ce->flags);
        ce->timeline = page_pack_bits(NULL, hwsp);
-       ce->ring = __intel_context_ring_size(ring_size);
+       ce->ring = NULL;
+       ce->ring_size = ring_size;
 
        i915_vm_put(ce->vm);
        ce->vm = i915_vm_get(vm);

diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index a27bac0a4bfb8bdb3baef7f43279640ebd46e087..8ada1afe3d2292e9c53e03790f97c18cacee0922 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -845,7 +845,7 @@ int lrc_alloc(struct intel_context *ce, struct intel_engine_cs *engine)
        if (IS_ERR(vma))
                return PTR_ERR(vma);
 
-       ring = intel_engine_create_ring(engine, (unsigned long)ce->ring);
+       ring = intel_engine_create_ring(engine, ce->ring_size);
        if (IS_ERR(ring)) {
                err = PTR_ERR(ring);
                goto err_vma;

diff --git a/drivers/gpu/drm/i915/gt/intel_migrate.c b/drivers/gpu/drm/i915/gt/intel_migrate.c
index 14afa1974ea59e8e709156dbae8b61f6c8d8ceb0..d0a7c934fd3bbfa86c5289e4ffbbfdd8765bdf5b 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_migrate.c
+++ b/drivers/gpu/drm/i915/gt/intel_migrate.c
@@ -232,7 +232,8 @@ struct intel_context *intel_migrate_create_context(struct intel_migrate *m)
        if (IS_ERR(ce))
                return ce;
 
-       ce->ring = __intel_context_ring_size(SZ_256K);
+       ce->ring = NULL;
+       ce->ring_size = SZ_256K;
 
        i915_vm_put(ce->vm);
        ce->vm = i915_vm_get(m->context->vm);

diff --git a/drivers/gpu/drm/i915/gt/selftest_execlists.c b/drivers/gpu/drm/i915/gt/selftest_execlists.c
index 08896ae027d5566f45c57c50341732f97f925c3a..d790b8b946ed914c8b75f8c9634c7536682fc260 100644 (file)
--- a/drivers/gpu/drm/i915/gt/selftest_execlists.c
+++ b/drivers/gpu/drm/i915/gt/selftest_execlists.c
@@ -2810,7 +2810,7 @@ static int __live_preempt_ring(struct intel_engine_cs *engine,
                        goto err_ce;
                }
 
-               tmp->ring = __intel_context_ring_size(ring_sz);
+               tmp->ring_size = ring_sz;
 
                err = intel_context_pin(tmp);
                if (err) {

diff --git a/drivers/gpu/drm/i915/gt/selftest_mocs.c b/drivers/gpu/drm/i915/gt/selftest_mocs.c
index b9bb0e6e97f7f9a9eac30ea9c4e06b5fe714902c..8763bbeca0f7779ade539f64ca4fd695054e8181 100644 (file)
--- a/drivers/gpu/drm/i915/gt/selftest_mocs.c
+++ b/drivers/gpu/drm/i915/gt/selftest_mocs.c
@@ -28,7 +28,7 @@ static struct intel_context *mocs_context_create(struct intel_engine_cs *engine)
                return ce;
 
        /* We build large requests to read the registers from the ring */
-       ce->ring = __intel_context_ring_size(SZ_16K);
+       ce->ring_size = SZ_16K;
 
        return ce;
 }

diff --git a/drivers/gpu/drm/i915/gt/selftest_timeline.c b/drivers/gpu/drm/i915/gt/selftest_timeline.c
index 64da0c91dec1d1d8754e20483571ec2c52b47890..d0b6a3afcf44e0c1028c780b9c4049359b4bced5 100644 (file)
--- a/drivers/gpu/drm/i915/gt/selftest_timeline.c
+++ b/drivers/gpu/drm/i915/gt/selftest_timeline.c
@@ -874,7 +874,7 @@ static int create_watcher(struct hwsp_watcher *w,
        if (IS_ERR(ce))
                return PTR_ERR(ce);
 
-       ce->ring = __intel_context_ring_size(ringsz);
+       ce->ring_size = ringsz;
        w->rq = intel_context_create_request(ce);
        intel_context_put(ce);
        if (IS_ERR(w->rq))

diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c
index 734c37c5e34743752538d20493b6b090bd8e1403..b56a8e37a3cd6acc794f8e36bfb89337153b101a 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -1409,11 +1409,8 @@ int intel_vgpu_setup_submission(struct intel_vgpu *vgpu)
                intel_context_set_single_submission(ce);
 
                /* Max ring buffer size */
-               if (!intel_uc_wants_guc_submission(&engine->gt->uc)) {
-                       const unsigned int ring_size = 512 * SZ_4K;
-
-                       ce->ring = __intel_context_ring_size(ring_size);
-               }
+               if (!intel_uc_wants_guc_submission(&engine->gt->uc))
+                       ce->ring_size = SZ_2M;
 
                s->shadow[i] = ce;
        }