lib/intel_allocator: Add intel_allocator core

For discrete gens we have to cease of using relocations when batch
buffers are submitted to GPU. On cards which have ppgtt we can use
softpin establishing addresses on our own.

We added simple allocator (taken from Mesa; works on lists) and
random allocator to exercise batches with different addresses. All
of that works for single VM (context) so we have to add additional
layer (intel_allocator) to support multiprocessing / multithreading.

For main IGT process (also for threads created in it) intel_allocator
resolves addresses "locally", just by mutexing access to global
allocator data (ctx/vm map). When fork() is in use children cannot
establish addresses on they own and have to contact to the thread
spawned within main IGT process. Currently SysV IPC message queue was
chosen as a communication channel between children and allocator thread.
Child calls same functions as main IGT process, only communication path
will be chosen instead of acquiring addresses locally.

v2:

Add intel_allocator_open_full() to allow user pass vm range.
Add strategy: NONE, LOW_TO_HIGH, HIGH_TO_LOW passed to allocator backend.

v3:

Child is now able to use allocator directly as standalone. It only need
to call intel_allocator_init() to reinitialize appropriate structures.

v4:

Add pseudo allocator - INTEL_ALLOCATOR_RELOC which just increments
offsets to avoid unnecessary conditional code.

v5:

Alter allocator core according to igt_map changes.

v6:

Add internal version __intel_allocator_alloc() to return
ALLOC_INVALID_ADDRESS without assertion.

v7:

Add libatomic for linking libigt library. It is required on some
archs, like mips.

Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com>
Signed-off-by: Dominik Grzegorzek <dominik.grzegorzek@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Petri Latvala <petri.latvala@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Petri Latvala <petri.latvala@intel.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/lib/igt_core.c b/lib/igt_core.c
index 2b4182f1..6597acfa 100644
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -58,6 +58,7 @@
 #include <glib.h>
 
 #include "drmtest.h"
+#include "intel_allocator.h"
 #include "intel_chipset.h"
 #include "intel_io.h"
 #include "igt_debugfs.h"
@@ -1412,6 +1413,19 @@ __noreturn static void exit_subtest(const char *result)
 	}
 	num_test_children = 0;
 
+	/*
+	 * When test completes - mostly in fail state it can leave allocated
+	 * objects. An allocator is not an exception as it is global IGT
+	 * entity and when test will allocate some ranges and then it will
+	 * fail no free/close likely will be called (controling potential
+	 * fails and clearing before assertions in IGT is not common).
+	 *
+	 * We call intel_allocator_init() then to prepare the allocator
+	 * infrastructure from scratch for each test. Init also removes
+	 * remnants from previous allocator run (if any).
+	 */
+	intel_allocator_init();
+
 	if (!in_dynamic_subtest)
 		_igt_dynamic_tests_executed = -1;