drm/i915: Make i915_engine_info pretty printer to standalone

We can use drm_printer to hide the differences between printk and
seq_printf, and so make the i915_engine_info pretty printer able to be
called from different contexts and not just debugfs. For instance, I
want to use the pretty printer to debug kselftests.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009110301.21705-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>

3 files changed, 168 insertions, 144 deletions

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index f7817c667958..9ec2bcd9a695 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -3292,9 +3292,9 @@ static int i915_display_info(struct seq_file *m, void *unused)
 static int i915_engine_info(struct seq_file *m, void *unused)
 {
 	struct drm_i915_private *dev_priv = node_to_i915(m->private);
-	struct i915_gpu_error *error = &dev_priv->gpu_error;
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
+	struct drm_printer p;
 
 	intel_runtime_pm_get(dev_priv);
 
@@ -3303,149 +3303,9 @@ static int i915_engine_info(struct seq_file *m, void *unused)
 	seq_printf(m, "Global active requests: %d\n",
 		   dev_priv->gt.active_requests);
 
-	for_each_engine(engine, dev_priv, id) {
-		struct intel_breadcrumbs *b = &engine->breadcrumbs;
-		struct drm_i915_gem_request *rq;
-		struct rb_node *rb;
-		u64 addr;
-
-		seq_printf(m, "%s\n", engine->name);
-		seq_printf(m, "\tcurrent seqno %x, last %x, hangcheck %x [%d ms], inflight %d\n",
-			   intel_engine_get_seqno(engine),
-			   intel_engine_last_submit(engine),
-			   engine->hangcheck.seqno,
-			   jiffies_to_msecs(jiffies - engine->hangcheck.action_timestamp),
-			   engine->timeline->inflight_seqnos);
-		seq_printf(m, "\tReset count: %d\n",
-			   i915_reset_engine_count(error, engine));
-
-		rcu_read_lock();
-
-		seq_printf(m, "\tRequests:\n");
-
-		rq = list_first_entry(&engine->timeline->requests,
-				      struct drm_i915_gem_request, link);
-		if (&rq->link != &engine->timeline->requests)
-			print_request(m, rq, "\t\tfirst  ");
-
-		rq = list_last_entry(&engine->timeline->requests,
-				     struct drm_i915_gem_request, link);
-		if (&rq->link != &engine->timeline->requests)
-			print_request(m, rq, "\t\tlast   ");
-
-		rq = i915_gem_find_active_request(engine);
-		if (rq) {
-			print_request(m, rq, "\t\tactive ");
-			seq_printf(m,
-				   "\t\t[head %04x, postfix %04x, tail %04x, batch 0x%08x_%08x]\n",
-				   rq->head, rq->postfix, rq->tail,
-				   rq->batch ? upper_32_bits(rq->batch->node.start) : ~0u,
-				   rq->batch ? lower_32_bits(rq->batch->node.start) : ~0u);
-		}
-
-		seq_printf(m, "\tRING_START: 0x%08x [0x%08x]\n",
-			   I915_READ(RING_START(engine->mmio_base)),
-			   rq ? i915_ggtt_offset(rq->ring->vma) : 0);
-		seq_printf(m, "\tRING_HEAD:  0x%08x [0x%08x]\n",
-			   I915_READ(RING_HEAD(engine->mmio_base)) & HEAD_ADDR,
-			   rq ? rq->ring->head : 0);
-		seq_printf(m, "\tRING_TAIL:  0x%08x [0x%08x]\n",
-			   I915_READ(RING_TAIL(engine->mmio_base)) & TAIL_ADDR,
-			   rq ? rq->ring->tail : 0);
-		seq_printf(m, "\tRING_CTL:   0x%08x [%s]\n",
-			   I915_READ(RING_CTL(engine->mmio_base)),
-			   I915_READ(RING_CTL(engine->mmio_base)) & (RING_WAIT | RING_WAIT_SEMAPHORE) ? "waiting" : "");
-
-		rcu_read_unlock();
-
-		addr = intel_engine_get_active_head(engine);
-		seq_printf(m, "\tACTHD:  0x%08x_%08x\n",
-			   upper_32_bits(addr), lower_32_bits(addr));
-		addr = intel_engine_get_last_batch_head(engine);
-		seq_printf(m, "\tBBADDR: 0x%08x_%08x\n",
-			   upper_32_bits(addr), lower_32_bits(addr));
-
-		if (i915_modparams.enable_execlists) {
-			const u32 *hws = &engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX];
-			struct intel_engine_execlists * const execlists = &engine->execlists;
-			u32 ptr, read, write;
-			unsigned int idx;
-
-			seq_printf(m, "\tExeclist status: 0x%08x %08x\n",
-				   I915_READ(RING_EXECLIST_STATUS_LO(engine)),
-				   I915_READ(RING_EXECLIST_STATUS_HI(engine)));
-
-			ptr = I915_READ(RING_CONTEXT_STATUS_PTR(engine));
-			read = GEN8_CSB_READ_PTR(ptr);
-			write = GEN8_CSB_WRITE_PTR(ptr);
-			seq_printf(m, "\tExeclist CSB read %d [%d cached], write %d [%d from hws], interrupt posted? %s\n",
-				   read, execlists->csb_head,
-				   write,
-				   intel_read_status_page(engine, intel_hws_csb_write_index(engine->i915)),
-				   yesno(test_bit(ENGINE_IRQ_EXECLIST,
-						  &engine->irq_posted)));
-			if (read >= GEN8_CSB_ENTRIES)
-				read = 0;
-			if (write >= GEN8_CSB_ENTRIES)
-				write = 0;
-			if (read > write)
-				write += GEN8_CSB_ENTRIES;
-			while (read < write) {
-				idx = ++read % GEN8_CSB_ENTRIES;
-				seq_printf(m, "\tExeclist CSB[%d]: 0x%08x [0x%08x in hwsp], context: %d [%d in hwsp]\n",
-					   idx,
-					   I915_READ(RING_CONTEXT_STATUS_BUF_LO(engine, idx)),
-					   hws[idx * 2],
-					   I915_READ(RING_CONTEXT_STATUS_BUF_HI(engine, idx)),
-					   hws[idx * 2 + 1]);
-			}
-
-			rcu_read_lock();
-			for (idx = 0; idx < execlists_num_ports(execlists); idx++) {
-				unsigned int count;
-
-				rq = port_unpack(&execlists->port[idx], &count);
-				if (rq) {
-					seq_printf(m, "\t\tELSP[%d] count=%d, ",
-						   idx, count);
-					print_request(m, rq, "rq: ");
-				} else {
-					seq_printf(m, "\t\tELSP[%d] idle\n",
-						   idx);
-				}
-			}
-			rcu_read_unlock();
-
-			spin_lock_irq(&engine->timeline->lock);
-			for (rb = execlists->first; rb; rb = rb_next(rb)) {
-				struct i915_priolist *p =
-					rb_entry(rb, typeof(*p), node);
-
-				list_for_each_entry(rq, &p->requests,
-						    priotree.link)
-					print_request(m, rq, "\t\tQ ");
-			}
-			spin_unlock_irq(&engine->timeline->lock);
-		} else if (INTEL_GEN(dev_priv) > 6) {
-			seq_printf(m, "\tPP_DIR_BASE: 0x%08x\n",
-				   I915_READ(RING_PP_DIR_BASE(engine)));
-			seq_printf(m, "\tPP_DIR_BASE_READ: 0x%08x\n",
-				   I915_READ(RING_PP_DIR_BASE_READ(engine)));
-			seq_printf(m, "\tPP_DIR_DCLV: 0x%08x\n",
-				   I915_READ(RING_PP_DIR_DCLV(engine)));
-		}
-
-		spin_lock_irq(&b->rb_lock);
-		for (rb = rb_first(&b->waiters); rb; rb = rb_next(rb)) {
-			struct intel_wait *w = rb_entry(rb, typeof(*w), node);
-
-			seq_printf(m, "\t%s [%d] waiting for %x\n",
-				   w->tsk->comm, w->tsk->pid, w->seqno);
-		}
-		spin_unlock_irq(&b->rb_lock);
-
-		seq_puts(m, "\n");
-	}
+	p = drm_seq_file_printer(m);
+	for_each_engine(engine, dev_priv, id)
+		intel_engine_dump(engine, &p);
 
 	intel_runtime_pm_put(dev_priv);
 
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index 807a7aafc089..a59b2a30ff5a 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -22,6 +22,8 @@
  *
  */
 
+#include <drm/drm_print.h>
+
 #include "i915_drv.h"
 #include "intel_ringbuffer.h"
 #include "intel_lrc.h"
@@ -1616,6 +1618,164 @@ bool intel_engine_can_store_dword(struct intel_engine_cs *engine)
 	}
 }
 
+static void print_request(struct drm_printer *m,
+			  struct drm_i915_gem_request *rq,
+			  const char *prefix)
+{
+	drm_printf(m, "%s%x [%x:%x] prio=%d @ %dms: %s\n", prefix,
+		   rq->global_seqno, rq->ctx->hw_id, rq->fence.seqno,
+		   rq->priotree.priority,
+		   jiffies_to_msecs(jiffies - rq->emitted_jiffies),
+		   rq->timeline->common->name);
+}
+
+void intel_engine_dump(struct intel_engine_cs *engine, struct drm_printer *m)
+{
+	struct intel_breadcrumbs *b = &engine->breadcrumbs;
+	struct i915_gpu_error *error = &engine->i915->gpu_error;
+	struct drm_i915_private *dev_priv = engine->i915;
+	struct drm_i915_gem_request *rq;
+	struct rb_node *rb;
+	u64 addr;
+
+	drm_printf(m, "%s\n", engine->name);
+	drm_printf(m, "\tcurrent seqno %x, last %x, hangcheck %x [%d ms], inflight %d\n",
+		   intel_engine_get_seqno(engine),
+		   intel_engine_last_submit(engine),
+		   engine->hangcheck.seqno,
+		   jiffies_to_msecs(jiffies - engine->hangcheck.action_timestamp),
+		   engine->timeline->inflight_seqnos);
+	drm_printf(m, "\tReset count: %d\n",
+		   i915_reset_engine_count(error, engine));
+
+	rcu_read_lock();
+
+	drm_printf(m, "\tRequests:\n");
+
+	rq = list_first_entry(&engine->timeline->requests,
+			      struct drm_i915_gem_request, link);
+	if (&rq->link != &engine->timeline->requests)
+		print_request(m, rq, "\t\tfirst  ");
+
+	rq = list_last_entry(&engine->timeline->requests,
+			     struct drm_i915_gem_request, link);
+	if (&rq->link != &engine->timeline->requests)
+		print_request(m, rq, "\t\tlast   ");
+
+	rq = i915_gem_find_active_request(engine);
+	if (rq) {
+		print_request(m, rq, "\t\tactive ");
+		drm_printf(m,
+			   "\t\t[head %04x, postfix %04x, tail %04x, batch 0x%08x_%08x]\n",
+			   rq->head, rq->postfix, rq->tail,
+			   rq->batch ? upper_32_bits(rq->batch->node.start) : ~0u,
+			   rq->batch ? lower_32_bits(rq->batch->node.start) : ~0u);
+	}
+
+	drm_printf(m, "\tRING_START: 0x%08x [0x%08x]\n",
+		   I915_READ(RING_START(engine->mmio_base)),
+		   rq ? i915_ggtt_offset(rq->ring->vma) : 0);
+	drm_printf(m, "\tRING_HEAD:  0x%08x [0x%08x]\n",
+		   I915_READ(RING_HEAD(engine->mmio_base)) & HEAD_ADDR,
+		   rq ? rq->ring->head : 0);
+	drm_printf(m, "\tRING_TAIL:  0x%08x [0x%08x]\n",
+		   I915_READ(RING_TAIL(engine->mmio_base)) & TAIL_ADDR,
+		   rq ? rq->ring->tail : 0);
+	drm_printf(m, "\tRING_CTL:   0x%08x [%s]\n",
+		   I915_READ(RING_CTL(engine->mmio_base)),
+		   I915_READ(RING_CTL(engine->mmio_base)) & (RING_WAIT | RING_WAIT_SEMAPHORE) ? "waiting" : "");
+
+	rcu_read_unlock();
+
+	addr = intel_engine_get_active_head(engine);
+	drm_printf(m, "\tACTHD:  0x%08x_%08x\n",
+		   upper_32_bits(addr), lower_32_bits(addr));
+	addr = intel_engine_get_last_batch_head(engine);
+	drm_printf(m, "\tBBADDR: 0x%08x_%08x\n",
+		   upper_32_bits(addr), lower_32_bits(addr));
+
+	if (i915_modparams.enable_execlists) {
+		const u32 *hws = &engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX];
+		struct intel_engine_execlists * const execlists = &engine->execlists;
+		u32 ptr, read, write;
+		unsigned int idx;
+
+		drm_printf(m, "\tExeclist status: 0x%08x %08x\n",
+			   I915_READ(RING_EXECLIST_STATUS_LO(engine)),
+			   I915_READ(RING_EXECLIST_STATUS_HI(engine)));
+
+		ptr = I915_READ(RING_CONTEXT_STATUS_PTR(engine));
+		read = GEN8_CSB_READ_PTR(ptr);
+		write = GEN8_CSB_WRITE_PTR(ptr);
+		drm_printf(m, "\tExeclist CSB read %d [%d cached], write %d [%d from hws], interrupt posted? %s\n",
+			   read, execlists->csb_head,
+			   write,
+			   intel_read_status_page(engine, intel_hws_csb_write_index(engine->i915)),
+			   yesno(test_bit(ENGINE_IRQ_EXECLIST,
+					  &engine->irq_posted)));
+		if (read >= GEN8_CSB_ENTRIES)
+			read = 0;
+		if (write >= GEN8_CSB_ENTRIES)
+			write = 0;
+		if (read > write)
+			write += GEN8_CSB_ENTRIES;
+		while (read < write) {
+			idx = ++read % GEN8_CSB_ENTRIES;
+			drm_printf(m, "\tExeclist CSB[%d]: 0x%08x [0x%08x in hwsp], context: %d [%d in hwsp]\n",
+				   idx,
+				   I915_READ(RING_CONTEXT_STATUS_BUF_LO(engine, idx)),
+				   hws[idx * 2],
+				   I915_READ(RING_CONTEXT_STATUS_BUF_HI(engine, idx)),
+				   hws[idx * 2 + 1]);
+		}
+
+		rcu_read_lock();
+		for (idx = 0; idx < execlists_num_ports(execlists); idx++) {
+			unsigned int count;
+
+			rq = port_unpack(&execlists->port[idx], &count);
+			if (rq) {
+				drm_printf(m, "\t\tELSP[%d] count=%d, ",
+					   idx, count);
+				print_request(m, rq, "rq: ");
+			} else {
+				drm_printf(m, "\t\tELSP[%d] idle\n",
+					   idx);
+			}
+		}
+		rcu_read_unlock();
+
+		spin_lock_irq(&engine->timeline->lock);
+		for (rb = execlists->first; rb; rb = rb_next(rb)) {
+			struct i915_priolist *p =
+				rb_entry(rb, typeof(*p), node);
+
+			list_for_each_entry(rq, &p->requests,
+					    priotree.link)
+				print_request(m, rq, "\t\tQ ");
+		}
+		spin_unlock_irq(&engine->timeline->lock);
+	} else if (INTEL_GEN(dev_priv) > 6) {
+		drm_printf(m, "\tPP_DIR_BASE: 0x%08x\n",
+			   I915_READ(RING_PP_DIR_BASE(engine)));
+		drm_printf(m, "\tPP_DIR_BASE_READ: 0x%08x\n",
+			   I915_READ(RING_PP_DIR_BASE_READ(engine)));
+		drm_printf(m, "\tPP_DIR_DCLV: 0x%08x\n",
+			   I915_READ(RING_PP_DIR_DCLV(engine)));
+	}
+
+	spin_lock_irq(&b->rb_lock);
+	for (rb = rb_first(&b->waiters); rb; rb = rb_next(rb)) {
+		struct intel_wait *w = rb_entry(rb, typeof(*w), node);
+
+		drm_printf(m, "\t%s [%d] waiting for %x\n",
+			   w->tsk->comm, w->tsk->pid, w->seqno);
+	}
+	spin_unlock_irq(&b->rb_lock);
+
+	drm_printf(m, "\n");
+}
+
 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 #include "selftests/mock_engine.c"
 #endif
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 0fedda17488c..17186f067408 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -7,6 +7,8 @@
 #include "i915_gem_timeline.h"
 #include "i915_selftest.h"
 
+struct drm_printer;
+
 #define I915_CMD_HASH_ORDER 9
 
 /* Early gen2 devices have a cacheline of just 32 bytes, using 64 is overkill,
@@ -839,4 +841,6 @@ void intel_engines_reset_default_submission(struct drm_i915_private *i915);
 
 bool intel_engine_can_store_dword(struct intel_engine_cs *engine);
 
+void intel_engine_dump(struct intel_engine_cs *engine, struct drm_printer *p);
+
 #endif /* _INTEL_RINGBUFFER_H_ */