lib/igt_dummyload: Introduce igt_spin_reset

Libify resetting a spin for reuse.

v2: use also in perf_pmu
v3: s/cmd_spin/cmd_precondition
v4: remove early return for !spin (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

2 files changed, 19 insertions, 0 deletions

diff --git a/lib/igt_dummyload.c b/lib/igt_dummyload.c
index 1d57a53c..65957ed1 100644
--- a/lib/igt_dummyload.c
+++ b/lib/igt_dummyload.c
@@ -260,6 +260,8 @@ emit_recursive_batch(igt_spin_t *spin,
 	obj[SCRATCH].flags = EXEC_OBJECT_PINNED;
 	obj[BATCH].flags = EXEC_OBJECT_PINNED;
 
+	spin->cmd_precondition = *spin->batch;
+
 	return fence_fd;
 }
 
@@ -367,6 +369,21 @@ void igt_spin_set_timeout(igt_spin_t *spin, int64_t ns)
 }
 
 /**
+ * igt_spin_reset:
+ * @spin: spin state from igt_spin_new()
+ *
+ * Reset the state of spin, allowing its reuse.
+ */
+void igt_spin_reset(igt_spin_t *spin)
+{
+	if (igt_spin_has_poll(spin))
+		spin->poll[SPIN_POLL_START_IDX] = 0;
+
+	*spin->batch = spin->cmd_precondition;
+	__sync_synchronize();
+}
+
+/**
  * igt_spin_end:
  * @spin: spin state from igt_spin_new()
  *
diff --git a/lib/igt_dummyload.h b/lib/igt_dummyload.h
index d6482089..34537f27 100644
--- a/lib/igt_dummyload.h
+++ b/lib/igt_dummyload.h
@@ -37,6 +37,7 @@ typedef struct igt_spin {
 	timer_t timer;
 	struct igt_list link;
 	uint32_t *batch;
+	uint32_t cmd_precondition;
 	int out_fence;
 	struct drm_i915_gem_exec_object2 obj[2];
 	struct drm_i915_gem_execbuffer2 execbuf;
@@ -68,6 +69,7 @@ igt_spin_factory(int fd, const struct igt_spin_factory *opts);
 	igt_spin_factory(fd, &((struct igt_spin_factory){__VA_ARGS__}))
 
 void igt_spin_set_timeout(igt_spin_t *spin, int64_t ns);
+void igt_spin_reset(igt_spin_t *spin);
 void igt_spin_end(igt_spin_t *spin);
 void igt_spin_free(int fd, igt_spin_t *spin);