drm/i915: Remove access to global seqno in the HWSP

Stop accessing the HWSP to read the global seqno, and stop tracking the
mirror in the engine's execution timeline -- it is unused.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190226094922.31617-2-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 3f6eddb6f6de7ee8bd21aa05296adcadb40874e3..061a767e3bed9de3f6fb8ccc66df87d004289601 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -526,8 +526,6 @@ static void error_print_engine(struct drm_i915_error_state_buf *m,
                                   ee->vm_info.pp_dir_base);
                }
        }
-       err_printf(m, "  seqno: 0x%08x\n", ee->seqno);
-       err_printf(m, "  last_seqno: 0x%08x\n", ee->last_seqno);
        err_printf(m, "  ring->head: 0x%08x\n", ee->cpu_ring_head);
        err_printf(m, "  ring->tail: 0x%08x\n", ee->cpu_ring_tail);
        err_printf(m, "  hangcheck timestamp: %dms (%lu%s)\n",
@@ -1216,8 +1214,6 @@ static void error_record_engine_registers(struct i915_gpu_state *error,
 
        ee->instpm = I915_READ(RING_INSTPM(engine->mmio_base));
        ee->acthd = intel_engine_get_active_head(engine);
-       ee->seqno = intel_engine_get_seqno(engine);
-       ee->last_seqno = intel_engine_last_submit(engine);
        ee->start = I915_READ_START(engine);
        ee->head = I915_READ_HEAD(engine);
        ee->tail = I915_READ_TAIL(engine);

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.h b/drivers/gpu/drm/i915/i915_gpu_error.h
index 94eaf8ab905132c75d0c0ce4c6757cec623a57ac..19ac102afaff407ad1ea3fc8c959f88cd9497fc4 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gpu_error.h
+++ b/drivers/gpu/drm/i915/i915_gpu_error.h
@@ -94,8 +94,6 @@ struct i915_gpu_state {
                u32 cpu_ring_head;
                u32 cpu_ring_tail;
 
-               u32 last_seqno;
-
                /* Register state */
                u32 start;
                u32 tail;
@@ -108,7 +106,6 @@ struct i915_gpu_state {
                u32 bbstate;
                u32 instpm;
                u32 instps;
-               u32 seqno;
                u64 bbaddr;
                u64 acthd;
                u32 fault_reg;

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 124b3e279c880675d14b04b7b5719f133493e873..596183f35b781fcc4ffea06f2e760050270ee121 100644 (file)
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -179,12 +179,11 @@ static void free_capture_list(struct i915_request *request)
 static void __retire_engine_request(struct intel_engine_cs *engine,
                                    struct i915_request *rq)
 {
-       GEM_TRACE("%s(%s) fence %llx:%lld, global=%d, current %d:%d\n",
+       GEM_TRACE("%s(%s) fence %llx:%lld, global=%d, current %d\n",
                  __func__, engine->name,
                  rq->fence.context, rq->fence.seqno,
                  rq->global_seqno,
-                 hwsp_seqno(rq),
-                 intel_engine_get_seqno(engine));
+                 hwsp_seqno(rq));
 
        GEM_BUG_ON(!i915_request_completed(rq));
 
@@ -243,12 +242,11 @@ static void i915_request_retire(struct i915_request *request)
 {
        struct i915_active_request *active, *next;
 
-       GEM_TRACE("%s fence %llx:%lld, global=%d, current %d:%d\n",
+       GEM_TRACE("%s fence %llx:%lld, global=%d, current %d\n",
                  request->engine->name,
                  request->fence.context, request->fence.seqno,
                  request->global_seqno,
-                 hwsp_seqno(request),
-                 intel_engine_get_seqno(request->engine));
+                 hwsp_seqno(request));
 
        lockdep_assert_held(&request->i915->drm.struct_mutex);
        GEM_BUG_ON(!i915_sw_fence_signaled(&request->submit));
@@ -305,12 +303,11 @@ void i915_request_retire_upto(struct i915_request *rq)
        struct intel_ring *ring = rq->ring;
        struct i915_request *tmp;
 
-       GEM_TRACE("%s fence %llx:%lld, global=%d, current %d:%d\n",
+       GEM_TRACE("%s fence %llx:%lld, global=%d, current %d\n",
                  rq->engine->name,
                  rq->fence.context, rq->fence.seqno,
                  rq->global_seqno,
-                 hwsp_seqno(rq),
-                 intel_engine_get_seqno(rq->engine));
+                 hwsp_seqno(rq));
 
        lockdep_assert_held(&rq->i915->drm.struct_mutex);
        GEM_BUG_ON(!i915_request_completed(rq));
@@ -354,12 +351,11 @@ void __i915_request_submit(struct i915_request *request)
        struct intel_engine_cs *engine = request->engine;
        u32 seqno;
 
-       GEM_TRACE("%s fence %llx:%lld -> global=%d, current %d:%d\n",
+       GEM_TRACE("%s fence %llx:%lld -> global=%d, current %d\n",
                  engine->name,
                  request->fence.context, request->fence.seqno,
                  engine->timeline.seqno + 1,
-                 hwsp_seqno(request),
-                 intel_engine_get_seqno(engine));
+                 hwsp_seqno(request));
 
        GEM_BUG_ON(!irqs_disabled());
        lockdep_assert_held(&engine->timeline.lock);
@@ -371,7 +367,6 @@ void __i915_request_submit(struct i915_request *request)
 
        seqno = next_global_seqno(&engine->timeline);
        GEM_BUG_ON(!seqno);
-       GEM_BUG_ON(intel_engine_signaled(engine, seqno));
 
        /* We may be recursing from the signal callback of another i915 fence */
        spin_lock_nested(&request->lock, SINGLE_DEPTH_NESTING);
@@ -409,12 +404,11 @@ void __i915_request_unsubmit(struct i915_request *request)
 {
        struct intel_engine_cs *engine = request->engine;
 
-       GEM_TRACE("%s fence %llx:%lld <- global=%d, current %d:%d\n",
+       GEM_TRACE("%s fence %llx:%lld <- global=%d, current %d\n",
                  engine->name,
                  request->fence.context, request->fence.seqno,
                  request->global_seqno,
-                 hwsp_seqno(request),
-                 intel_engine_get_seqno(engine));
+                 hwsp_seqno(request));
 
        GEM_BUG_ON(!irqs_disabled());
        lockdep_assert_held(&engine->timeline.lock);
@@ -425,7 +419,6 @@ void __i915_request_unsubmit(struct i915_request *request)
         */
        GEM_BUG_ON(!request->global_seqno);
        GEM_BUG_ON(request->global_seqno != engine->timeline.seqno);
-       GEM_BUG_ON(intel_engine_has_completed(engine, request->global_seqno));
        engine->timeline.seqno--;
 
        /* We may be recursing from the signal callback of another i915 fence */

diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index 39a08932a95a0091c8030910e0a2938340da7ecd..55d6123dbba4b12854ff16a5bbbb942743d3dbd5 100644 (file)
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -788,7 +788,6 @@ static void nop_submit_request(struct i915_request *request)
        spin_lock_irqsave(&engine->timeline.lock, flags);
        __i915_request_submit(request);
        i915_request_mark_complete(request);
-       intel_engine_write_global_seqno(engine, request->global_seqno);
        spin_unlock_irqrestore(&engine->timeline.lock, flags);
 
        intel_engine_queue_breadcrumbs(engine);

diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index 57bc5c4fb3ff29318f3d82e852f12faca9b583cc..ec859c7b8c7c9a3993e29a39b9d03d0a79185278 100644 (file)
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -455,12 +455,6 @@ cleanup:
        return err;
 }
 
-void intel_engine_write_global_seqno(struct intel_engine_cs *engine, u32 seqno)
-{
-       intel_write_status_page(engine, I915_GEM_HWS_INDEX, seqno);
-       GEM_BUG_ON(intel_engine_get_seqno(engine) != seqno);
-}
-
 static void intel_engine_init_batch_pool(struct intel_engine_cs *engine)
 {
        i915_gem_batch_pool_init(&engine->batch_pool, engine);
@@ -1011,10 +1005,6 @@ bool intel_engine_is_idle(struct intel_engine_cs *engine)
        if (i915_reset_failed(engine->i915))
                return true;
 
-       /* Any inflight/incomplete requests? */
-       if (!intel_engine_signaled(engine, intel_engine_last_submit(engine)))
-               return false;
-
        /* Waiting to drain ELSP? */
        if (READ_ONCE(engine->execlists.active)) {
                struct tasklet_struct *t = &engine->execlists.tasklet;
@@ -1497,9 +1487,7 @@ void intel_engine_dump(struct intel_engine_cs *engine,
        if (i915_reset_failed(engine->i915))
                drm_printf(m, "*** WEDGED ***\n");
 
-       drm_printf(m, "\tcurrent seqno %x, last %x, hangcheck %x/%x [%d ms]\n",
-                  intel_engine_get_seqno(engine),
-                  intel_engine_last_submit(engine),
+       drm_printf(m, "\tHangcheck %x:%x [%d ms]\n",
                   engine->hangcheck.last_seqno,
                   engine->hangcheck.next_seqno,
                   jiffies_to_msecs(jiffies - engine->hangcheck.action_timestamp));

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 0516fc6b965284277e60d2b6108480fa975b47b9..09b56b84e00743ae2dc36efd98792f6cfab6619c 100644 (file)
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -528,13 +528,12 @@ static void execlists_submit_ports(struct intel_engine_cs *engine)
                        desc = execlists_update_context(rq);
                        GEM_DEBUG_EXEC(port[n].context_id = upper_32_bits(desc));
 
-                       GEM_TRACE("%s in[%d]:  ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n",
+                       GEM_TRACE("%s in[%d]:  ctx=%d.%d, global=%d (fence %llx:%lld) (current %d), prio=%d\n",
                                  engine->name, n,
                                  port[n].context_id, count,
                                  rq->global_seqno,
                                  rq->fence.context, rq->fence.seqno,
                                  hwsp_seqno(rq),
-                                 intel_engine_get_seqno(engine),
                                  rq_prio(rq));
                } else {
                        GEM_BUG_ON(!n);
@@ -840,13 +839,12 @@ execlists_cancel_port_requests(struct intel_engine_execlists * const execlists)
        while (num_ports-- && port_isset(port)) {
                struct i915_request *rq = port_request(port);
 
-               GEM_TRACE("%s:port%u global=%d (fence %llx:%lld), (current %d:%d)\n",
+               GEM_TRACE("%s:port%u global=%d (fence %llx:%lld), (current %d)\n",
                          rq->engine->name,
                          (unsigned int)(port - execlists->port),
                          rq->global_seqno,
                          rq->fence.context, rq->fence.seqno,
-                         hwsp_seqno(rq),
-                         intel_engine_get_seqno(rq->engine));
+                         hwsp_seqno(rq));
 
                GEM_BUG_ON(!execlists->active);
                execlists_context_schedule_out(rq,
@@ -902,8 +900,7 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
        struct rb_node *rb;
        unsigned long flags;
 
-       GEM_TRACE("%s current %d\n",
-                 engine->name, intel_engine_get_seqno(engine));
+       GEM_TRACE("%s\n", engine->name);
 
        /*
         * Before we call engine->cancel_requests(), we should have exclusive
@@ -952,10 +949,6 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
                        kmem_cache_free(engine->i915->priorities, p);
        }
 
-       intel_write_status_page(engine,
-                               I915_GEM_HWS_INDEX,
-                               intel_engine_last_submit(engine));
-
        /* Remaining _unready_ requests will be nop'ed when submitted */
 
        execlists->queue_priority_hint = INT_MIN;
@@ -1071,14 +1064,13 @@ static void process_csb(struct intel_engine_cs *engine)
                                                EXECLISTS_ACTIVE_USER));
 
                rq = port_unpack(port, &count);
-               GEM_TRACE("%s out[0]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n",
+               GEM_TRACE("%s out[0]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d), prio=%d\n",
                          engine->name,
                          port->context_id, count,
                          rq ? rq->global_seqno : 0,
                          rq ? rq->fence.context : 0,
                          rq ? rq->fence.seqno : 0,
                          rq ? hwsp_seqno(rq) : 0,
-                         intel_engine_get_seqno(engine),
                          rq ? rq_prio(rq) : 0);
 
                /* Check the context/desc id for this event matches */
@@ -1946,10 +1938,9 @@ static void execlists_reset(struct intel_engine_cs *engine, bool stalled)
        /* Following the reset, we need to reload the CSB read/write pointers */
        reset_csb_pointers(&engine->execlists);
 
-       GEM_TRACE("%s seqno=%d, current=%d, stalled? %s\n",
+       GEM_TRACE("%s seqno=%d, stalled? %s\n",
                  engine->name,
                  rq ? rq->global_seqno : 0,
-                 intel_engine_get_seqno(engine),
                  yesno(stalled));
        if (!rq)
                goto out_unlock;

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 870184bbd1690c8d80e1a063b8c5c7cedfcdb278..2d59e299044895cb97c62e53e6a88b7c10a26300 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -782,10 +782,9 @@ static void reset_ring(struct intel_engine_cs *engine, bool stalled)
                }
        }
 
-       GEM_TRACE("%s seqno=%d, current=%d, stalled? %s\n",
+       GEM_TRACE("%s seqno=%d, stalled? %s\n",
                  engine->name,
                  rq ? rq->global_seqno : 0,
-                 intel_engine_get_seqno(engine),
                  yesno(stalled));
        /*
         * The guilty request will get skipped on a hung engine.
@@ -924,10 +923,6 @@ static void cancel_requests(struct intel_engine_cs *engine)
                i915_request_mark_complete(request);
        }
 
-       intel_write_status_page(engine,
-                               I915_GEM_HWS_INDEX,
-                               intel_engine_last_submit(engine));
-
        /* Remaining _unready_ requests will be nop'ed when submitted */
 
        spin_unlock_irqrestore(&engine->timeline.lock, flags);

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 2869aaa9d22597a58e9473d8a05356f93ae180a6..551b3daa741c3e62e1a8b43cfa24c3be6d901431 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -848,8 +848,6 @@ __intel_ring_space(unsigned int head, unsigned int tail, unsigned int size)
        return (head - tail - CACHELINE_BYTES) & (size - 1);
 }
 
-void intel_engine_write_global_seqno(struct intel_engine_cs *engine, u32 seqno);
-
 int intel_engine_setup_common(struct intel_engine_cs *engine);
 int intel_engine_init_common(struct intel_engine_cs *engine);
 void intel_engine_cleanup_common(struct intel_engine_cs *engine);
@@ -867,44 +865,6 @@ void intel_engine_set_hwsp_writemask(struct intel_engine_cs *engine, u32 mask);
 u64 intel_engine_get_active_head(const struct intel_engine_cs *engine);
 u64 intel_engine_get_last_batch_head(const struct intel_engine_cs *engine);
 
-static inline u32 intel_engine_last_submit(struct intel_engine_cs *engine)
-{
-       /*
-        * We are only peeking at the tail of the submit queue (and not the
-        * queue itself) in order to gain a hint as to the current active
-        * state of the engine. Callers are not expected to be taking
-        * engine->timeline->lock, nor are they expected to be concerned
-        * wtih serialising this hint with anything, so document it as
-        * a hint and nothing more.
-        */
-       return READ_ONCE(engine->timeline.seqno);
-}
-
-static inline u32 intel_engine_get_seqno(struct intel_engine_cs *engine)
-{
-       return intel_read_status_page(engine, I915_GEM_HWS_INDEX);
-}
-
-static inline bool intel_engine_signaled(struct intel_engine_cs *engine,
-                                        u32 seqno)
-{
-       return i915_seqno_passed(intel_engine_get_seqno(engine), seqno);
-}
-
-static inline bool intel_engine_has_completed(struct intel_engine_cs *engine,
-                                             u32 seqno)
-{
-       GEM_BUG_ON(!seqno);
-       return intel_engine_signaled(engine, seqno);
-}
-
-static inline bool intel_engine_has_started(struct intel_engine_cs *engine,
-                                           u32 seqno)
-{
-       GEM_BUG_ON(!seqno);
-       return intel_engine_signaled(engine, seqno - 1);
-}
-
 void intel_engine_get_instdone(struct intel_engine_cs *engine,
                               struct intel_instdone *instdone);
 

diff --git a/drivers/gpu/drm/i915/selftests/i915_request.c b/drivers/gpu/drm/i915/selftests/i915_request.c
index 03cc8ab6a620f520700cba2506c3ccdf7a3b0542..7da52e3d67af7b4cfc96d75d3e051950aa991bf4 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/i915_request.c
+++ b/drivers/gpu/drm/i915/selftests/i915_request.c
@@ -226,8 +226,7 @@ static int igt_request_rewind(void *arg)
        mutex_unlock(&i915->drm.struct_mutex);
 
        if (i915_request_wait(vip, 0, HZ) == -ETIME) {
-               pr_err("timed out waiting for high priority request, vip.seqno=%d, current seqno=%d\n",
-                      vip->global_seqno, intel_engine_get_seqno(i915->engine[RCS]));
+               pr_err("timed out waiting for high priority request\n");
                goto err;
        }
 

diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index 08f0cab02e0f331d9ecfbb03e25cc5f7b241852d..79bf27606ab8bb84f2ff4fb7712e1d476e2dfa3d 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -86,8 +86,6 @@ static struct mock_request *first_request(struct mock_engine *engine)
 static void advance(struct mock_request *request)
 {
        list_del_init(&request->link);
-       intel_engine_write_global_seqno(request->base.engine,
-                                       request->base.global_seqno);
        i915_request_mark_complete(&request->base);
        GEM_BUG_ON(!i915_request_completed(&request->base));
 
@@ -278,7 +276,6 @@ void mock_engine_flush(struct intel_engine_cs *engine)
 
 void mock_engine_reset(struct intel_engine_cs *engine)
 {
-       intel_engine_write_global_seqno(engine, 0);
 }
 
 void mock_engine_free(struct intel_engine_cs *engine)