[PATCH i-g-t 4/4] tests/intel/xe_fault_injection: Inject errors during xe_guc_ct_send_recv & xe_guc_mmio_send_recv.

[Satyanarayana K V P]

Use the kernel fault injection infrastructure to test error handling
of xe during driver probe when executing xe_guc_ct_send_recv() /
xe_guc_mmio_send_recv() so that more code paths are tested, such as
error handling and unwinding.

Error can be injected using:
igt at xe_fault_injection@probe-fail-guc-xe_guc_ct_send_recv
igt at xe_fault_injection@probe-fail-guc-xe_guc_mmio_send_recv

Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p at intel.com>
Cc: Michał Wajdeczko <michal.wajdeczko at intel.com>
Cc: Francois Dugast <francois.dugast at intel.com>
---
 tests/intel/xe_fault_injection.c | 41 ++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/tests/intel/xe_fault_injection.c b/tests/intel/xe_fault_injection.c
index 9432828c2..288a5c384 100644
--- a/tests/intel/xe_fault_injection.c
+++ b/tests/intel/xe_fault_injection.c
@@ -231,6 +231,34 @@ inject_fault_probe(int fd, char pci_slot[], const char function_name[])
 	xe_sysfs_driver_do(fd, pci_slot, XE_SYSFS_DRIVER_TRY_UNBIND);
 }
 
+/**
+ * SUBTEST: probe-fail-guc-%s
+ * Description: inject an error in the injectable function %arg[1] then reprobe driver
+ * Functionality: fault
+ *
+ * arg[1]:
+ * @xe_guc_mmio_send_recv:	Inject an error when calling xe_guc_mmio_send_recv
+ * @xe_guc_ct_send_recv:	Inject an error when calling xe_guc_ct_send_recv
+ */
+
+static void probe_fail_guc(int fd, char pci_slot[], const char function_name[],
+		struct fault_injection_params *fault_params)
+{
+	int iter_start = 0, iter_end = 0, iter = 0;
+
+	igt_assert(fault_params);
+
+	/* Get the iteration count from environment */
+	iter = get_fault_inject_iter();
+	iter_start = iter ? : 0;
+	iter_end = iter ? iter + 1 : INJECT_ITERATIONS;
+	for (int i = iter_start; i < iter_end; i++) {
+		fault_params->space = i;
+		setup_injection_fault(fault_params);
+		inject_fault_probe(fd, pci_slot, function_name);
+	}
+}
+
 static int
 simple_vm_create(int fd, unsigned int flags)
 {
@@ -330,6 +358,7 @@ igt_main
 {
 	int fd;
 	char pci_slot[NAME_MAX];
+	struct fault_injection_params fault_params;
 	const struct section {
 		const char *name;
 		unsigned int flags;
@@ -363,6 +392,11 @@ igt_main
 		{ "xe_vma_ops_alloc" },
 		{ }
 	};
+	const struct section guc_fail_functions[] = {
+		{ "xe_guc_mmio_send_recv" },
+		{ "xe_guc_ct_send_recv" },
+		{ }
+	};
 
 	igt_fixture {
 		igt_require(fail_function_injection_enabled());
@@ -387,6 +421,13 @@ igt_main
 		igt_subtest_f("inject-fault-probe-function-%s", s->name)
 			inject_fault_probe(fd, pci_slot, s->name);
 
+	for (const struct section *s = guc_fail_functions; s->name; s++)
+		igt_subtest_f("probe-fail-guc-%s", s->name) {
+			memcpy(&fault_params, &default_fault_params,
+					sizeof(struct fault_injection_params));
+			probe_fail_guc(fd, pci_slot, s->name, &fault_params);
+		}
+
 	igt_fixture {
 		drm_close_driver(fd);
 		xe_sysfs_driver_do(fd, pci_slot, XE_SYSFS_DRIVER_BIND);
-- 
2.35.3