drm/i915: Record the current requests queue for execlists upon hang

Mika wanted to know what requests were pending at the time of a hang as
we now track which requests we have submitted to the hardware.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161013101815.26978-1-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index bf397b643cc040d41e2a7f0703f4948040e3958e..6360e807c6ba4a6e9e746f454f95bbf645774623 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -832,10 +832,11 @@ struct drm_i915_error_state {
                struct drm_i915_error_request {
                        long jiffies;
                        pid_t pid;
+                       u32 context;
                        u32 seqno;
                        u32 head;
                        u32 tail;
-               } *requests;
+               } *requests, execlist[2];
 
                struct drm_i915_error_waiter {
                        char comm[TASK_COMM_LEN];

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 78cc13b9b2a5c1f1569aa7aee9c55f5728b8c507..026b78c66219df153d2322bd8a8254b966f892bc 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -363,6 +363,20 @@ static void error_print_instdone(struct drm_i915_error_state_buf *m,
                           ee->instdone.row[slice][subslice]);
 }
 
+static void error_print_request(struct drm_i915_error_state_buf *m,
+                               const char *prefix,
+                               struct drm_i915_error_request *erq)
+{
+       if (!erq->seqno)
+               return;
+
+       err_printf(m, "%s pid %d, seqno %8x:%08x, emitted %dms ago, head %08x, tail %08x\n",
+                  prefix, erq->pid,
+                  erq->context, erq->seqno,
+                  jiffies_to_msecs(jiffies - erq->jiffies),
+                  erq->head, erq->tail);
+}
+
 static void error_print_engine(struct drm_i915_error_state_buf *m,
                               struct drm_i915_error_engine *ee)
 {
@@ -434,6 +448,8 @@ static void error_print_engine(struct drm_i915_error_state_buf *m,
        err_printf(m, "  hangcheck: %s [%d]\n",
                   hangcheck_action_to_str(ee->hangcheck_action),
                   ee->hangcheck_score);
+       error_print_request(m, "  ELSP[0]: ", &ee->execlist[0]);
+       error_print_request(m, "  ELSP[1]: ", &ee->execlist[1]);
 }
 
 void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
@@ -649,14 +665,8 @@ int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
                        err_printf(m, "%s --- %d requests\n",
                                   dev_priv->engine[i].name,
                                   ee->num_requests);
-                       for (j = 0; j < ee->num_requests; j++) {
-                               err_printf(m, "  pid %d, seqno 0x%08x, emitted %ld, head 0x%08x, tail 0x%08x\n",
-                                          ee->requests[j].pid,
-                                          ee->requests[j].seqno,
-                                          ee->requests[j].jiffies,
-                                          ee->requests[j].head,
-                                          ee->requests[j].tail);
-                       }
+                       for (j = 0; j < ee->num_requests; j++)
+                               error_print_request(m, " ", &ee->requests[j]);
                }
 
                if (IS_ERR(ee->waiters)) {
@@ -1155,6 +1165,20 @@ static void error_record_engine_registers(struct drm_i915_error_state *error,
        }
 }
 
+static void record_request(struct drm_i915_gem_request *request,
+                          struct drm_i915_error_request *erq)
+{
+       erq->context = request->ctx->hw_id;
+       erq->seqno = request->fence.seqno;
+       erq->jiffies = request->emitted_jiffies;
+       erq->head = request->head;
+       erq->tail = request->tail;
+
+       rcu_read_lock();
+       erq->pid = request->ctx->pid ? pid_nr(request->ctx->pid) : 0;
+       rcu_read_unlock();
+}
+
 static void engine_record_requests(struct intel_engine_cs *engine,
                                   struct drm_i915_gem_request *first,
                                   struct drm_i915_error_engine *ee)
@@ -1178,8 +1202,6 @@ static void engine_record_requests(struct intel_engine_cs *engine,
        count = 0;
        request = first;
        list_for_each_entry_from(request, &engine->request_list, link) {
-               struct drm_i915_error_request *erq;
-
                if (count >= ee->num_requests) {
                        /*
                         * If the ring request list was changed in
@@ -1199,19 +1221,22 @@ static void engine_record_requests(struct intel_engine_cs *engine,
                        break;
                }
 
-               erq = &ee->requests[count++];
-               erq->seqno = request->fence.seqno;
-               erq->jiffies = request->emitted_jiffies;
-               erq->head = request->head;
-               erq->tail = request->tail;
-
-               rcu_read_lock();
-               erq->pid = request->ctx->pid ? pid_nr(request->ctx->pid) : 0;
-               rcu_read_unlock();
+               record_request(request, &ee->requests[count++]);
        }
        ee->num_requests = count;
 }
 
+static void error_record_engine_execlists(struct intel_engine_cs *engine,
+                                         struct drm_i915_error_engine *ee)
+{
+       unsigned int n;
+
+       for (n = 0; n < ARRAY_SIZE(engine->execlist_port); n++)
+               if (engine->execlist_port[n].request)
+                       record_request(engine->execlist_port[n].request,
+                                      &ee->execlist[n]);
+}
+
 static void i915_gem_record_rings(struct drm_i915_private *dev_priv,
                                  struct drm_i915_error_state *error)
 {
@@ -1236,6 +1261,7 @@ static void i915_gem_record_rings(struct drm_i915_private *dev_priv,
 
                error_record_engine_registers(error, engine, ee);
                error_record_engine_waiters(engine, ee);
+               error_record_engine_execlists(engine, ee);
 
                request = i915_gem_find_active_request(engine);
                if (request) {