test/gem_gtt_speed: Add a baseline test for the performance of a CPU mmap

When looking at the pwrite/pread/wc performance, it is useful to judge
that against the performance of an ordinary CPU mmap.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

lib/drmtest.c

@@ -311,7 +311,7 @@ uint32_t gem_create(int fd, int size)
 	return create.handle;
 }
 
-void *gem_mmap(int fd, uint32_t handle, int size, int prot)
+void *gem_mmap__gtt(int fd, uint32_t handle, int size, int prot)
 {
 	struct drm_i915_gem_mmap_gtt mmap_arg;
 	void *ptr;
@@ -327,6 +327,19 @@ void *gem_mmap(int fd, uint32_t handle, int size, int prot)
 	return ptr;
 }
 
+void *gem_mmap__cpu(int fd, uint32_t handle, int size, int prot)
+{
+	struct drm_i915_gem_mmap mmap_arg;
+
+	mmap_arg.handle = handle;
+	mmap_arg.offset = 0;
+	mmap_arg.size = size;
+	if (drmIoctl(fd, DRM_IOCTL_I915_GEM_MMAP, &mmap_arg))
+		return NULL;
+
+	return (void *)(uintptr_t)mmap_arg.addr_ptr;
+}
+
 uint64_t gem_aperture_size(int fd)
 {
 	struct drm_i915_gem_get_aperture aperture;

lib/drmtest.h

@@ -52,7 +52,11 @@ void gem_set_domain(int fd, uint32_t handle,
 		    uint32_t read_domains, uint32_t write_domain);
 void gem_sync(int fd, uint32_t handle);
 uint32_t gem_create(int fd, int size);
-void *gem_mmap(int fd, uint32_t handle, int size, int prot);
+
+void *gem_mmap__gtt(int fd, uint32_t handle, int size, int prot);
+void *gem_mmap__cpu(int fd, uint32_t handle, int size, int prot);
+#define gem_mmap gem_mmap__gtt
+
 uint64_t gem_aperture_size(int fd);
 uint64_t gem_mappable_aperture_size(void);
 int gem_madvise(int fd, uint32_t handle, int state);