intel: provide a callback to clean up after intel_measure_gather

The caller may have passed ownership of intel_measure_batch structures
to intel_measure until they are ready to be gathered.  The caller
needs a notification when rendering is complete and snapshots have
been processed, so it can free the resources that measure the batch.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16571>

src/intel/common/intel_measure.c

@@ -215,6 +215,7 @@ intel_measure_init(struct intel_measure_device *device)
 
    device->config = NULL;
    device->frame = 0;
+   device->release_batch = NULL;
    pthread_mutex_init(&device->mutex, NULL);
    list_inithead(&device->queued_snapshots);
 
@@ -661,6 +662,8 @@ intel_measure_gather(struct intel_measure_device *measure_device,
 
       batch->index = 0;
       batch->frame = 0;
+      if (measure_device->release_batch)
+         measure_device->release_batch(batch);
    }
 
    intel_measure_print(measure_device, info);

src/intel/common/intel_measure.h

@@ -124,9 +124,13 @@ struct intel_measure_ringbuffer {
    struct intel_measure_buffered_result results[0];
 };
 
+/* This function will be called when enqueued snapshots have been processed */
+typedef void (*intel_measure_release_batch_cb)(struct intel_measure_batch *base);
+
 struct intel_measure_device {
    struct intel_measure_config *config;
    unsigned frame;
+   intel_measure_release_batch_cb release_batch;
 
    /* Holds the list of (iris/anv)_measure_batch snapshots that have been
     * submitted for rendering, but have not completed.