Re: [PATCH v3 9/9] memfd-test: run fuse test on hugetlb backend memory

[Mike Kravetz]

On 11/07/2017 04:28 AM, Marc-Andrà Lureau wrote:
> Suggested-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
> Signed-off-by: Marc-Andrà Lureau <marcandre.lureau@xxxxxxxxxx>

Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>

-- 
Mike Kravetz

> ---
>  tools/testing/selftests/memfd/fuse_test.c      | 38 ++++++++++++++++++++------
>  tools/testing/selftests/memfd/run_fuse_test.sh |  2 +-
>  tools/testing/selftests/memfd/run_tests.sh     |  1 +
>  3 files changed, 32 insertions(+), 9 deletions(-)
> 
> diff --git a/tools/testing/selftests/memfd/fuse_test.c b/tools/testing/selftests/memfd/fuse_test.c
> index 795a25ba8521..b018e835737d 100644
> --- a/tools/testing/selftests/memfd/fuse_test.c
> +++ b/tools/testing/selftests/memfd/fuse_test.c
> @@ -38,6 +38,8 @@
>  #define MFD_DEF_SIZE 8192
>  #define STACK_SIZE 65536
>  
> +static size_t mfd_def_size = MFD_DEF_SIZE;
> +
>  static int mfd_assert_new(const char *name, loff_t sz, unsigned int flags)
>  {
>  	int r, fd;
> @@ -123,7 +125,7 @@ static void *mfd_assert_mmap_shared(int fd)
>  	void *p;
>  
>  	p = mmap(NULL,
> -		 MFD_DEF_SIZE,
> +		 mfd_def_size,
>  		 PROT_READ | PROT_WRITE,
>  		 MAP_SHARED,
>  		 fd,
> @@ -141,7 +143,7 @@ static void *mfd_assert_mmap_private(int fd)
>  	void *p;
>  
>  	p = mmap(NULL,
> -		 MFD_DEF_SIZE,
> +		 mfd_def_size,
>  		 PROT_READ | PROT_WRITE,
>  		 MAP_PRIVATE,
>  		 fd,
> @@ -174,7 +176,7 @@ static int sealing_thread_fn(void *arg)
>  	usleep(200000);
>  
>  	/* unmount mapping before sealing to avoid i_mmap_writable failures */
> -	munmap(global_p, MFD_DEF_SIZE);
> +	munmap(global_p, mfd_def_size);
>  
>  	/* Try sealing the global file; expect EBUSY or success. Current
>  	 * kernels will never succeed, but in the future, kernels might
> @@ -224,7 +226,7 @@ static void join_sealing_thread(pid_t pid)
>  
>  int main(int argc, char **argv)
>  {
> -	static const char zero[MFD_DEF_SIZE];
> +	char *zero;
>  	int fd, mfd, r;
>  	void *p;
>  	int was_sealed;
> @@ -235,6 +237,25 @@ int main(int argc, char **argv)
>  		abort();
>  	}
>  
> +	if (argc >= 3) {
> +		if (!strcmp(argv[2], "hugetlbfs")) {
> +			unsigned long hpage_size = default_huge_page_size();
> +
> +			if (!hpage_size) {
> +				printf("Unable to determine huge page size\n");
> +				abort();
> +			}
> +
> +			hugetlbfs_test = 1;
> +			mfd_def_size = hpage_size * 2;
> +		} else {
> +			printf("Unknown option: %s\n", argv[2]);
> +			abort();
> +		}
> +	}
> +
> +	zero = calloc(sizeof(*zero), mfd_def_size);
> +
>  	/* open FUSE memfd file for GUP testing */
>  	printf("opening: %s\n", argv[1]);
>  	fd = open(argv[1], O_RDONLY | O_CLOEXEC);
> @@ -245,7 +266,7 @@ int main(int argc, char **argv)
>  
>  	/* create new memfd-object */
>  	mfd = mfd_assert_new("kern_memfd_fuse",
> -			     MFD_DEF_SIZE,
> +			     mfd_def_size,
>  			     MFD_CLOEXEC | MFD_ALLOW_SEALING);
>  
>  	/* mmap memfd-object for writing */
> @@ -264,7 +285,7 @@ int main(int argc, char **argv)
>  	 * This guarantees that the receive-buffer is pinned for 1s until the
>  	 * data is written into it. The racing ADD_SEALS should thus fail as
>  	 * the pages are still pinned. */
> -	r = read(fd, p, MFD_DEF_SIZE);
> +	r = read(fd, p, mfd_def_size);
>  	if (r < 0) {
>  		printf("read() failed: %m\n");
>  		abort();
> @@ -291,10 +312,10 @@ int main(int argc, char **argv)
>  	 * enough to avoid any in-flight writes. */
>  
>  	p = mfd_assert_mmap_private(mfd);
> -	if (was_sealed && memcmp(p, zero, MFD_DEF_SIZE)) {
> +	if (was_sealed && memcmp(p, zero, mfd_def_size)) {
>  		printf("memfd sealed during read() but data not discarded\n");
>  		abort();
> -	} else if (!was_sealed && !memcmp(p, zero, MFD_DEF_SIZE)) {
> +	} else if (!was_sealed && !memcmp(p, zero, mfd_def_size)) {
>  		printf("memfd sealed after read() but data discarded\n");
>  		abort();
>  	}
> @@ -303,6 +324,7 @@ int main(int argc, char **argv)
>  	close(fd);
>  
>  	printf("fuse: DONE\n");
> +	free(zero);
>  
>  	return 0;
>  }
> diff --git a/tools/testing/selftests/memfd/run_fuse_test.sh b/tools/testing/selftests/memfd/run_fuse_test.sh
> index 407df68dfe27..22e572e2d66a 100755
> --- a/tools/testing/selftests/memfd/run_fuse_test.sh
> +++ b/tools/testing/selftests/memfd/run_fuse_test.sh
> @@ -10,6 +10,6 @@ set -e
>  
>  mkdir mnt
>  ./fuse_mnt ./mnt
> -./fuse_test ./mnt/memfd
> +./fuse_test ./mnt/memfd $@
>  fusermount -u ./mnt
>  rmdir ./mnt
> diff --git a/tools/testing/selftests/memfd/run_tests.sh b/tools/testing/selftests/memfd/run_tests.sh
> index daabb350697c..c2d41ed81b24 100755
> --- a/tools/testing/selftests/memfd/run_tests.sh
> +++ b/tools/testing/selftests/memfd/run_tests.sh
> @@ -60,6 +60,7 @@ fi
>  # Run the hugetlbfs test
>  #
>  ./memfd_test hugetlbfs
> +./run_fuse_test.sh hugetlbfs
>  
>  #
>  # Give back any huge pages allocated for the test
>