diff mbox

[i-g-t,1/3] lib/dummyload: Add pollable spin batch

Message ID 20180322111712.9056-1-tvrtko.ursulin@linux.intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Tvrtko Ursulin March 22, 2018, 11:17 a.m. UTC
From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Pollable spin batch exports a spin->running pointer which can be checked
by dereferencing it to see if the spinner is actually executing on the
GPU.

This is useful for tests which want to make sure they do not proceed with
their next step whilst the spinner is potentially only being processed by
the driver and not actually executing.

Pollable spinner can be created with igt_spin_batch_new_poll or
__igt_spin_batch_new_poll, after which a loop similar to:

	while (!*(volatile bool *)spin->running)
		;

Can be used to wait until the spinner start execution.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
---
 lib/igt_dummyload.c  | 192 ++++++++++++++++++++++++++++++++++++++++-----------
 lib/igt_dummyload.h  |  11 +++
 lib/igt_gt.c         |   2 +-
 lib/ioctl_wrappers.c |   2 +-
 lib/ioctl_wrappers.h |   1 +
 5 files changed, 167 insertions(+), 41 deletions(-)

Comments

Chris Wilson March 22, 2018, 11:25 a.m. UTC | #1
Quoting Tvrtko Ursulin (2018-03-22 11:17:10)
> From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> 
> Pollable spin batch exports a spin->running pointer which can be checked
> by dereferencing it to see if the spinner is actually executing on the
> GPU.
> 
> This is useful for tests which want to make sure they do not proceed with
> their next step whilst the spinner is potentially only being processed by
> the driver and not actually executing.
> 
> Pollable spinner can be created with igt_spin_batch_new_poll or
> __igt_spin_batch_new_poll, after which a loop similar to:
> 
>         while (!*(volatile bool *)spin->running)
>                 ;

Let's actually make READ_ONCE() a common thing and make this a
convenient igt_spin_busywait_until_running() (igt_spin_spin)?

> Can be used to wait until the spinner start execution.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris
diff mbox

Patch

diff --git a/lib/igt_dummyload.c b/lib/igt_dummyload.c
index dbc92e8f2951..98ab7ac2c6e9 100644
--- a/lib/igt_dummyload.c
+++ b/lib/igt_dummyload.c
@@ -74,35 +74,48 @@  fill_reloc(struct drm_i915_gem_relocation_entry *reloc,
 	reloc->write_domain = write_domains;
 }
 
-static int emit_recursive_batch(igt_spin_t *spin,
-				int fd, uint32_t ctx, unsigned engine,
-				uint32_t dep, bool out_fence)
+#define OUT_FENCE	(1 << 0)
+#define POLL_RUN	(1 << 1)
+
+static int
+emit_recursive_batch(igt_spin_t *spin, int fd, uint32_t ctx, unsigned engine,
+		     uint32_t dep, unsigned int flags)
 {
 #define SCRATCH 0
 #define BATCH 1
 	const int gen = intel_gen(intel_get_drm_devid(fd));
-	struct drm_i915_gem_exec_object2 obj[2];
-	struct drm_i915_gem_relocation_entry relocs[2];
-	struct drm_i915_gem_execbuffer2 execbuf;
+	struct drm_i915_gem_relocation_entry relocs[2], *r;
+	struct drm_i915_gem_execbuffer2 *execbuf;
+	struct drm_i915_gem_exec_object2 *obj;
 	unsigned int engines[16];
 	unsigned int nengine;
 	int fence_fd = -1;
-	uint32_t *batch;
+	uint32_t *batch, *batch_start;
 	int i;
 
 	nengine = 0;
 	if (engine == ALL_ENGINES) {
-		for_each_engine(fd, engine)
-			if (engine)
+		for_each_engine(fd, engine) {
+			if (engine) {
+			if (flags & POLL_RUN)
+				igt_require(!(flags & POLL_RUN) ||
+					    gem_can_store_dword(fd, engine));
+
 				engines[nengine++] = engine;
+			}
+		}
 	} else {
 		gem_require_ring(fd, engine);
+		igt_require(!(flags & POLL_RUN) ||
+			    gem_can_store_dword(fd, engine));
 		engines[nengine++] = engine;
 	}
 	igt_require(nengine);
 
-	memset(&execbuf, 0, sizeof(execbuf));
-	memset(obj, 0, sizeof(obj));
+	memset(&spin->execbuf, 0, sizeof(spin->execbuf));
+	execbuf = &spin->execbuf;
+	memset(spin->obj, 0, sizeof(spin->obj));
+	obj = spin->obj;
 	memset(relocs, 0, sizeof(relocs));
 
 	obj[BATCH].handle = gem_create(fd, BATCH_SIZE);
@@ -113,19 +126,66 @@  static int emit_recursive_batch(igt_spin_t *spin,
 				       	BATCH_SIZE, PROT_WRITE);
 	gem_set_domain(fd, obj[BATCH].handle,
 			I915_GEM_DOMAIN_GTT, I915_GEM_DOMAIN_GTT);
-	execbuf.buffer_count++;
+	execbuf->buffer_count++;
+	batch_start = batch;
 
 	if (dep) {
+		igt_assert(!(flags & POLL_RUN));
+
 		/* dummy write to dependency */
 		obj[SCRATCH].handle = dep;
 		fill_reloc(&relocs[obj[BATCH].relocation_count++],
 			   dep, 1020,
 			   I915_GEM_DOMAIN_RENDER,
 			   I915_GEM_DOMAIN_RENDER);
-		execbuf.buffer_count++;
+		execbuf->buffer_count++;
+	} else if (flags & POLL_RUN) {
+		unsigned int offset;
+
+		igt_assert(!dep);
+
+		if (gen == 4 || gen == 5)
+			execbuf->flags |= I915_EXEC_SECURE;
+
+		spin->poll_handle = gem_create(fd, 4096);
+
+		if (__gem_set_caching(fd, spin->poll_handle,
+				      I915_CACHING_CACHED) == 0)
+			spin->running = __gem_mmap__cpu(fd, spin->poll_handle,
+							0, 4096,
+							PROT_READ | PROT_WRITE);
+		else
+			spin->running = __gem_mmap__wc(fd, spin->poll_handle,
+						       0, 4096,
+						       PROT_READ | PROT_WRITE);
+		igt_assert(spin->running);
+		igt_assert_eq(*spin->running, 0);
+
+		*batch++ = MI_STORE_DWORD_IMM | (gen < 6 ? 1 << 22 : 0);
+
+		if (gen >= 8) {
+			offset = 1;
+			*batch++ = 0;
+			*batch++ = 0;
+		} else if (gen >= 4) {
+			offset = 2;
+			*batch++ = 0;
+			*batch++ = 0;
+		} else {
+			offset = 1;
+			batch[-1]--;
+			*batch++ = 0;
+		}
+
+		*batch++ = 1;
+
+		obj[SCRATCH].handle = spin->poll_handle;
+		fill_reloc(&relocs[obj[BATCH].relocation_count++],
+			   spin->poll_handle, offset, 0, 0);
+		execbuf->buffer_count++;
 	}
 
-	spin->batch = batch;
+	spin->batch = batch = batch_start + 64 / sizeof(*batch);
 	spin->handle = obj[BATCH].handle;
 
 	/* Allow ourselves to be preempted */
@@ -145,40 +205,42 @@  static int emit_recursive_batch(igt_spin_t *spin,
 	batch += 1000;
 
 	/* recurse */
-	fill_reloc(&relocs[obj[BATCH].relocation_count],
-		   obj[BATCH].handle, (batch - spin->batch) + 1,
-		   I915_GEM_DOMAIN_COMMAND, 0);
+	r = &relocs[obj[BATCH].relocation_count++];
+	r->target_handle = obj[BATCH].handle;
+	r->offset = (batch + 1 - batch_start) * sizeof(*batch);
+	r->read_domains = I915_GEM_DOMAIN_COMMAND;
+	r->delta = 64;
 	if (gen >= 8) {
 		*batch++ = MI_BATCH_BUFFER_START | 1 << 8 | 1;
-		*batch++ = 0;
+		*batch++ = r->delta;
 		*batch++ = 0;
 	} else if (gen >= 6) {
 		*batch++ = MI_BATCH_BUFFER_START | 1 << 8;
-		*batch++ = 0;
+		*batch++ = r->delta;
 	} else {
 		*batch++ = MI_BATCH_BUFFER_START | 2 << 6;
-		*batch = 0;
-		if (gen < 4) {
-			*batch |= 1;
-			relocs[obj[BATCH].relocation_count].delta = 1;
-		}
+		if (gen < 4)
+			r->delta |= 1;
+		*batch = r->delta;
 		batch++;
 	}
-	obj[BATCH].relocation_count++;
 	obj[BATCH].relocs_ptr = to_user_pointer(relocs);
 
-	execbuf.buffers_ptr = to_user_pointer(obj + (2 - execbuf.buffer_count));
-	execbuf.rsvd1 = ctx;
+	execbuf->buffers_ptr = to_user_pointer(obj +
+					       (2 - execbuf->buffer_count));
+	execbuf->rsvd1 = ctx;
 
-	if (out_fence)
-		execbuf.flags |= I915_EXEC_FENCE_OUT;
+	if (flags & OUT_FENCE)
+		execbuf->flags |= I915_EXEC_FENCE_OUT;
 
 	for (i = 0; i < nengine; i++) {
-		execbuf.flags &= ~ENGINE_MASK;
-		execbuf.flags |= engines[i];
-		gem_execbuf_wr(fd, &execbuf);
-		if (out_fence) {
-			int _fd = execbuf.rsvd2 >> 32;
+		execbuf->flags &= ~ENGINE_MASK;
+		execbuf->flags |= engines[i];
+
+		gem_execbuf_wr(fd, execbuf);
+
+		if (flags & OUT_FENCE) {
+			int _fd = execbuf->rsvd2 >> 32;
 
 			igt_assert(_fd >= 0);
 			if (fence_fd == -1) {
@@ -194,12 +256,20 @@  static int emit_recursive_batch(igt_spin_t *spin,
 		}
 	}
 
+	/* Make it easier for callers to resubmit. */
+
+	obj[BATCH].relocation_count = 0;
+	obj[BATCH].relocs_ptr = 0;
+
+	obj[SCRATCH].flags = EXEC_OBJECT_PINNED;
+	obj[BATCH].flags = EXEC_OBJECT_PINNED;
+
 	return fence_fd;
 }
 
 static igt_spin_t *
 ___igt_spin_batch_new(int fd, uint32_t ctx, unsigned engine, uint32_t dep,
-		      int out_fence)
+		      unsigned int flags)
 {
 	igt_spin_t *spin;
 
@@ -207,7 +277,7 @@  ___igt_spin_batch_new(int fd, uint32_t ctx, unsigned engine, uint32_t dep,
 	igt_assert(spin);
 
 	spin->out_fence = emit_recursive_batch(spin, fd, ctx, engine, dep,
-					       out_fence);
+					       flags);
 
 	pthread_mutex_lock(&list_lock);
 	igt_list_add(&spin->link, &spin_list);
@@ -219,7 +289,7 @@  ___igt_spin_batch_new(int fd, uint32_t ctx, unsigned engine, uint32_t dep,
 igt_spin_t *
 __igt_spin_batch_new(int fd, uint32_t ctx, unsigned engine, uint32_t dep)
 {
-	return ___igt_spin_batch_new(fd, ctx, engine, dep, false);
+	return ___igt_spin_batch_new(fd, ctx, engine, dep, 0);
 }
 
 /**
@@ -253,7 +323,7 @@  igt_spin_batch_new(int fd, uint32_t ctx, unsigned engine, uint32_t dep)
 igt_spin_t *
 __igt_spin_batch_new_fence(int fd, uint32_t ctx, unsigned engine)
 {
-	return ___igt_spin_batch_new(fd, ctx, engine, 0, true);
+	return ___igt_spin_batch_new(fd, ctx, engine, 0, OUT_FENCE);
 }
 
 /**
@@ -286,6 +356,42 @@  igt_spin_batch_new_fence(int fd, uint32_t ctx, unsigned engine)
 	return spin;
 }
 
+igt_spin_t *
+__igt_spin_batch_new_poll(int fd, uint32_t ctx, unsigned engine)
+{
+	return ___igt_spin_batch_new(fd, ctx, engine, 0, POLL_RUN);
+}
+
+/**
+ * igt_spin_batch_new_poll:
+ * @fd: open i915 drm file descriptor
+ * @engine: Ring to execute batch OR'd with execbuf flags. If value is less
+ *          than 0, execute on all available rings.
+ *
+ * Start a recursive batch on a ring. Immediately returns a #igt_spin_t that
+ * contains the batch's handle that can be waited upon. The returned structure
+ * must be passed to igt_spin_batch_free() for post-processing.
+ *
+ * igt_spin_t->running will containt a pointer which target will change from
+ * zero to one once the spinner actually starts executing on the GPU.
+ *
+ * Returns:
+ * Structure with helper internal state for igt_spin_batch_free().
+ */
+igt_spin_t *
+igt_spin_batch_new_poll(int fd, uint32_t ctx, unsigned engine)
+{
+	igt_spin_t *spin;
+
+	igt_require_gem(fd);
+	igt_require(gem_mmap__has_wc(fd));
+
+	spin = __igt_spin_batch_new_poll(fd, ctx, engine);
+	igt_assert(gem_bo_busy(fd, spin->handle));
+
+	return spin;
+}
+
 static void notify(union sigval arg)
 {
 	igt_spin_t *spin = arg.sival_ptr;
@@ -340,6 +446,8 @@  void igt_spin_batch_end(igt_spin_t *spin)
 	if (!spin)
 		return;
 
+	igt_assert(*spin->batch == MI_ARB_CHK ||
+		   *spin->batch == MI_BATCH_BUFFER_END);
 	*spin->batch = MI_BATCH_BUFFER_END;
 	__sync_synchronize();
 }
@@ -365,7 +473,13 @@  void igt_spin_batch_free(int fd, igt_spin_t *spin)
 		timer_delete(spin->timer);
 
 	igt_spin_batch_end(spin);
-	gem_munmap(spin->batch, BATCH_SIZE);
+	gem_munmap((void *)((unsigned long)spin->batch & (~4095UL)),
+		   BATCH_SIZE);
+
+	if (spin->running) {
+		gem_munmap(spin->running, 4096);
+		gem_close(fd, spin->poll_handle);
+	}
 
 	gem_close(fd, spin->handle);
 
diff --git a/lib/igt_dummyload.h b/lib/igt_dummyload.h
index 4103e4ab9e36..3103935a309b 100644
--- a/lib/igt_dummyload.h
+++ b/lib/igt_dummyload.h
@@ -36,6 +36,10 @@  typedef struct igt_spin {
 	struct igt_list link;
 	uint32_t *batch;
 	int out_fence;
+	struct drm_i915_gem_exec_object2 obj[2];
+	struct drm_i915_gem_execbuffer2 execbuf;
+	uint32_t poll_handle;
+	bool *running;
 } igt_spin_t;
 
 igt_spin_t *__igt_spin_batch_new(int fd,
@@ -55,6 +59,13 @@  igt_spin_t *igt_spin_batch_new_fence(int fd,
 				     uint32_t ctx,
 				     unsigned engine);
 
+igt_spin_t *__igt_spin_batch_new_poll(int fd,
+				       uint32_t ctx,
+				       unsigned engine);
+igt_spin_t *igt_spin_batch_new_poll(int fd,
+				    uint32_t ctx,
+				    unsigned engine);
+
 void igt_spin_batch_set_timeout(igt_spin_t *spin, int64_t ns);
 void igt_spin_batch_end(igt_spin_t *spin);
 void igt_spin_batch_free(int fd, igt_spin_t *spin);
diff --git a/lib/igt_gt.c b/lib/igt_gt.c
index 01aebc670862..4569fd36bd85 100644
--- a/lib/igt_gt.c
+++ b/lib/igt_gt.c
@@ -609,7 +609,7 @@  bool gem_can_store_dword(int fd, unsigned int engine)
 	if (gen == 3 && (info->is_grantsdale || info->is_alviso))
 		return false; /* only supports physical addresses */
 
-	if (gen == 6 && (engine & ~(3<<13)) == I915_EXEC_BSD)
+	if (gen == 6 && ((engine & 0x3f) == I915_EXEC_BSD))
 		return false; /* kills the machine! */
 
 	if (info->is_broadwater)
diff --git a/lib/ioctl_wrappers.c b/lib/ioctl_wrappers.c
index 8748cfcfc04f..4e1a08bf06b4 100644
--- a/lib/ioctl_wrappers.c
+++ b/lib/ioctl_wrappers.c
@@ -198,7 +198,7 @@  void gem_set_tiling(int fd, uint32_t handle, uint32_t tiling, uint32_t stride)
 	igt_assert(__gem_set_tiling(fd, handle, tiling, stride) == 0);
 }
 
-static int __gem_set_caching(int fd, uint32_t handle, uint32_t caching)
+int __gem_set_caching(int fd, uint32_t handle, uint32_t caching)
 {
 	struct drm_i915_gem_caching arg;
 	int err;
diff --git a/lib/ioctl_wrappers.h b/lib/ioctl_wrappers.h
index 13fbe3c103c0..b966f72c90a8 100644
--- a/lib/ioctl_wrappers.h
+++ b/lib/ioctl_wrappers.h
@@ -61,6 +61,7 @@  bool gem_get_tiling(int fd, uint32_t handle, uint32_t *tiling, uint32_t *swizzle
 void gem_set_tiling(int fd, uint32_t handle, uint32_t tiling, uint32_t stride);
 int __gem_set_tiling(int fd, uint32_t handle, uint32_t tiling, uint32_t stride);
 
+int __gem_set_caching(int fd, uint32_t handle, uint32_t caching);
 void gem_set_caching(int fd, uint32_t handle, uint32_t caching);
 uint32_t gem_get_caching(int fd, uint32_t handle);
 uint32_t gem_flink(int fd, uint32_t handle);