[PATCH i-g-t v3 2/2] tests/intel/xe_fault_injection: Inject errors during xe_guc_ct_send_recv

[Bernatowicz, Marcin]

On 1/20/2025 1:28 PM, Satyanarayana K V P wrote:
> Use the kernel fault injection infrastructure to test error handling
> of xe at enabling of VFs stage when executing xe_guc_ct_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@enable-vfs-fail-xe_guc_ct_send_recv
> 
> v2: Updated guc_fail_* to enable_vfs_*
> Added igt_skip_on(!igt_sriov_is_pf(fd)) to skip test when run without
> enabling sriov.
> 
> v3: Fixed documentation build error
> ERROR: Missing documentation for igt at xe_fault_injection@enable-vfs-fail-xe_guc_ct_send_recv
> ERROR: Unneeded documentation for igt at xe_fault_injection@guc-fail-xe_guc_ct_send_recv
> 
> Cc: Matthew Brost <matthew.brost at intel.com>
> Cc: Michał Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Francois Dugast <francois.dugast at intel.com>
> Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p at intel.com>
> ---
>   tests/intel/xe_fault_injection.c | 63 ++++++++++++++++++++++++++++++++
>   1 file changed, 63 insertions(+)
> 
> diff --git a/tests/intel/xe_fault_injection.c b/tests/intel/xe_fault_injection.c
> index 3a0e2aa29..81ecc1131 100644
> --- a/tests/intel/xe_fault_injection.c
> +++ b/tests/intel/xe_fault_injection.c
> @@ -19,12 +19,14 @@
>   #include "igt_sysfs.h"
>   #include "lib/igt_syncobj.h"
>   #include "lib/intel_pat.h"
> +#include "lib/igt_sriov_device.h"
>   #include "xe/xe_ioctl.h"
>   #include "xe/xe_query.h"
>   
>   #define INJECT_ERRNO	-ENOMEM
>   #define BO_ADDR		0x1a0000
>   #define BO_SIZE		(1024*1024)
> +#define NUM_VFS		1
>   
>   enum injection_list_action {
>   	INJECTION_LIST_ADD,
> @@ -281,6 +283,55 @@ vm_bind_fail(int fd, const char function_name[])
>   	igt_assert_eq(simple_vm_bind(fd, vm), 0);
>   }
>   
> +static int sriov_enable_vfs(int fd, int num_vfs)
> +{
> +	int sysfs;
> +	bool ret;
> +
> +	sysfs = igt_sysfs_open(fd);
> +	igt_assert_fd(sysfs);
> +
> +	ret = __igt_sysfs_set_u32(sysfs, "device/sriov_numvfs", num_vfs);
> +	close(sysfs);
> +
> +	return ret;
> +}
> +
> +/**
> + * SUBTEST: enable-vfs-fail-%s
> + * Description: inject an error in function %arg[1] used when xe interacts with guc to make it fail
> + * Functionality: fault
> + *
> + * arg[1]:
> + * @xe_guc_ct_send_recv:               xe_guc_ct_send_recv
> + */
> +
> +static void
> +enable_vfs_fail(int fd, int num_vfs, const char function_name[])
> +{
> +	bool autoprobe_en = 0;

NIT: maybe just bool autoprobe = 0 ?

> +
> +	ignore_faults_in_dmesg(function_name);
> +	injection_list_do(INJECTION_LIST_ADD, function_name);
> +	set_retval(function_name, INJECT_ERRNO);
> +
> +	autoprobe_en = igt_sriov_is_driver_autoprobe_enabled(fd);
> +
> +	if (autoprobe_en)
> +		igt_sriov_disable_driver_autoprobe(fd);
> +
> +	/* igt_sriov_enable_vfs can't be used here as it is causing abort on any error.
> +	 * Since error in this test is expected, we have written our own static function here.
> +	 */
> +	sriov_enable_vfs(fd, num_vfs);
> +
> +	igt_assert_eq(-errno, INJECT_ERRNO);
> +	injection_list_do(INJECTION_LIST_REMOVE, function_name);
> +
> +	if (autoprobe_en)
> +		igt_sriov_enable_driver_autoprobe(fd);
> +}
> +
>   igt_main
>   {
>   	int fd;
> @@ -319,6 +370,10 @@ igt_main
>   		{ "xe_vma_ops_alloc" },
>   		{ }
>   	};
> +	const struct section enable_vfs_fail_functions[] = {
> +		{ "xe_guc_ct_send_recv" },
> +		{ }
> +	};
>   
>   	igt_fixture {
>   		igt_require(fail_function_injection_enabled());
> @@ -335,6 +390,14 @@ igt_main
>   		igt_subtest_f("vm-bind-fail-%s", s->name)
>   			vm_bind_fail(fd, s->name);
>   
> +	for (const struct section *s = enable_vfs_fail_functions; s->name; s++)
> +		igt_subtest_f("enable-vfs-fail-%s", s->name) {
> +			/* Skip the test if not running with SRIOV
> +			 */
> +			igt_skip_on(!igt_sriov_is_pf(fd));

NIT: Using igt_require without negation improves readability

igt_require(igt_sriov_is_pf(fd));

> +			enable_vfs_fail(fd, NUM_VFS, s->name);
> +		}
> +
>   	igt_fixture {
>   		xe_sysfs_driver_do(fd, pci_slot, XE_SYSFS_DRIVER_UNBIND);
>   	}

With small nits,
Reviewed-by: Marcin Bernatowicz <marcin.bernatowicz at linux.intel.com>