Re: [igt-dev] [PATCH i-g-t v2 6/6] tests/xe/mmap: sanity check small-bar

["Souza, Jose" <jose.souza@intel.com>]

On Fri, 2023-06-09 at 16:43 +0100, Matthew Auld wrote:
> Some basic sanity checks.
> 
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> ---
>  lib/xe/xe_ioctl.c  | 28 ++++++++++----
>  lib/xe/xe_ioctl.h  |  2 +
>  tests/xe/xe_mmap.c | 95 +++++++++++++++++++++++++++++++++++++++++++++-
>  3 files changed, 117 insertions(+), 8 deletions(-)
> 
> diff --git a/lib/xe/xe_ioctl.c b/lib/xe/xe_ioctl.c
> index 66a8393fe..6c14f03d1 100644
> --- a/lib/xe/xe_ioctl.c
> +++ b/lib/xe/xe_ioctl.c
> @@ -232,17 +232,31 @@ void xe_vm_destroy(int fd, uint32_t vm)
>  	igt_assert_eq(igt_ioctl(fd, DRM_IOCTL_XE_VM_DESTROY, &destroy), 0);
>  }
>  
> +uint32_t __xe_bo_create_flags(int fd, uint32_t vm, uint64_t size, uint32_t flags,
> +			      uint32_t *handle)
> +{
> +	struct drm_xe_gem_create create = {
> +		.vm_id = vm,
> +		.size = size,
> +		.flags = flags,
> +	};
> +	int err;
> +
> +	err = igt_ioctl(fd, DRM_IOCTL_XE_GEM_CREATE, &create);
> +	if (err)
> +		return err;
> +
> +	*handle = create.handle;
> +	return 0;
> +}
> +
>  uint32_t xe_bo_create_flags(int fd, uint32_t vm, uint64_t size, uint32_t flags)
>  {
> -	struct drm_xe_gem_create create = {
> -		.vm_id = vm,
> -		.size = size,
> -		.flags = flags,
> -	};
> +	uint32_t handle;
>  
> -	igt_assert_eq(igt_ioctl(fd, DRM_IOCTL_XE_GEM_CREATE, &create), 0);
> +	igt_assert_eq(__xe_bo_create_flags(fd, vm, size, flags, &handle), 0);
>  
> -	return create.handle;
> +	return handle;
>  }
>  
>  uint32_t xe_bo_create(int fd, int gt, uint32_t vm, uint64_t size)
> diff --git a/lib/xe/xe_ioctl.h b/lib/xe/xe_ioctl.h
> index 049cd183d..85389eff5 100644
> --- a/lib/xe/xe_ioctl.h
> +++ b/lib/xe/xe_ioctl.h
> @@ -64,6 +64,8 @@ void xe_vm_unbind_all_async(int fd, uint32_t vm, uint32_t engine,
>  			    uint32_t bo, struct drm_xe_sync *sync,
>  			    uint32_t num_syncs);
>  void xe_vm_destroy(int fd, uint32_t vm);
> +uint32_t __xe_bo_create_flags(int fd, uint32_t vm, uint64_t size, uint32_t flags,
> +			      uint32_t *handle);
>  uint32_t xe_bo_create_flags(int fd, uint32_t vm, uint64_t size, uint32_t flags);
>  uint32_t xe_bo_create(int fd, int gt, uint32_t vm, uint64_t size);
>  uint32_t xe_engine_create(int fd, uint32_t vm,
> diff --git a/tests/xe/xe_mmap.c b/tests/xe/xe_mmap.c
> index 7bfe72e51..b75d8dc5a 100644
> --- a/tests/xe/xe_mmap.c
> +++ b/tests/xe/xe_mmap.c
> @@ -18,14 +18,21 @@
>  #include "xe/xe_ioctl.h"
>  #include "xe/xe_query.h"
>  
> +#include <setjmp.h>
> +#include <signal.h>
>  #include <string.h>
>  
> -
>  /**
>   * SUBTEST: system
>   * Description: Test mmap on system memory
>   */
>  
> +/**
> + * SUBTEST: small-bar
> + * Description: Sanity check mmap behaviour on small-bar systems
> + * GPU requirements: GPU needs to have dedicated VRAM and using small-bar
> + */
> +
>  /**
>   * SUBTEST: %s
>   * Description: Test mmap on %arg[1] memory
> @@ -111,6 +118,86 @@ static void test_bad_object(int fd)
>  	do_ioctl_err(fd, DRM_IOCTL_XE_GEM_MMAP_OFFSET, &mmo, ENOENT);
>  }
>  
> +static jmp_buf jmp;
> +
> +__noreturn static void sigtrap(int sig)
> +{
> +	siglongjmp(jmp, sig);
> +}
> +
> +static void trap_sigbus(uint32_t *ptr)
> +{
> +	sighandler_t old_sigbus;
> +
> +	old_sigbus = signal(SIGBUS, sigtrap);
> +	switch (sigsetjmp(jmp, SIGBUS)) {
> +	case SIGBUS:
> +		break;
> +	case 0:
> +		*ptr = 0xdeadbeaf;
> +	default:
> +		igt_assert(!"reached");
> +		break;
> +	}
> +	signal(SIGBUS, old_sigbus);
> +}
> +
> +/**
> + * SUBTEST: small-bar
> + * Description: Test mmap behaviour on small-bar systems.
> + *
> + */
> +static void test_small_bar(int fd)
> +{
> +	uint32_t visible_size = xe_visible_vram_size(fd, 0);
> +	uint32_t bo;
> +	uint64_t mmo;
> +	uint32_t *map;
> +
> +	/* Some 2BIG invalid cases */
> +	igt_assert_neq(__xe_bo_create_flags(fd, 0, visible_size,
> +					    visible_vram_memory(fd, 0), &bo),
> +		       0);

Are you sure that visible_size will always fail? What about when running it Intel GPU Flex?

Other than that LGTM.

> +	igt_assert_neq(__xe_bo_create_flags(fd, 0, visible_size + 4096,
> +					    visible_vram_memory(fd, 0), &bo),
> +		       0);
> +
> +	/* Normal operation */
> +	bo = xe_bo_create_flags(fd, 0, visible_size / 4,
> +				visible_vram_memory(fd, 0));
> +	mmo = xe_bo_mmap_offset(fd, bo);
> +	map = mmap(NULL, 4096, PROT_WRITE, MAP_SHARED, fd, mmo);
> +	igt_assert(map != MAP_FAILED);
> +
> +	map[0] = 0xdeadbeaf;
> +
> +	munmap(map, 4096);
> +	gem_close(fd, bo);
> +
> +	/* Normal operation with system memory spilling */
> +	bo = xe_bo_create_flags(fd, 0, visible_size,
> +				visible_vram_memory(fd, 0) |
> +				system_memory(fd));
> +	mmo = xe_bo_mmap_offset(fd, bo);
> +	map = mmap(NULL, 4096, PROT_WRITE, MAP_SHARED, fd, mmo);
> +	igt_assert(map != MAP_FAILED);
> +
> +	map[0] = 0xdeadbeaf;
> +
> +	munmap(map, 4096);
> +	gem_close(fd, bo);
> +
> +	/* Bogus operation with SIGBUS */
> +	bo = xe_bo_create_flags(fd, 0, visible_size + 4096,
> +				vram_memory(fd, 0));
> +	mmo = xe_bo_mmap_offset(fd, bo);
> +	map = mmap(NULL, 4096, PROT_WRITE, MAP_SHARED, fd, mmo);
> +	igt_assert(map != MAP_FAILED);
> +
> +	trap_sigbus(map);
> +	gem_close(fd, bo);
> +}
> +
>  igt_main
>  {
>  	int fd;
> @@ -138,6 +225,12 @@ igt_main
>  	igt_subtest("bad-object")
>  		test_bad_object(fd);
>  
> +	igt_subtest("small-bar") {
> +		igt_require(xe_visible_vram_size(fd, 0));
> +		igt_require(xe_visible_vram_size(fd, 0) < xe_vram_size(fd, 0));
> +		test_small_bar(fd);
> +	}
> +
>  	igt_fixture {
>  		xe_device_put(fd);
>  		close(fd);