[igt-dev] [PATCH v5 4/8] tests/fbdev: Add tests for unaligned reads on framebuffer memory

[Petri Latvala]

On Thu, Nov 19, 2020 at 02:47:42PM +0100, Thomas Zimmermann wrote:
> The tests for unaligned reads start and stop reading within pages.
> 
> v4:
> 	* declare pagesize as volatile
> 	* test sysconf() success with igt_require() (Petri)
> 	* clarify error message about frambuffer size (Petri)
> 	* replace igt_require() by igt_assert() in "unaligned-read" (Petri)
> 	* add unaligned-read test to CI
> v3:
> 	* put igt_describe() before igt_subtest() (Petri)
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
> ---
>  tests/fbdev.c                         | 40 +++++++++++++++++++++++++--
>  tests/intel-ci/fast-feedback.testlist |  1 +
>  2 files changed, 39 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/fbdev.c b/tests/fbdev.c
> index d8c78a5e..be9e95c1 100644
> --- a/tests/fbdev.c
> +++ b/tests/fbdev.c
> @@ -64,10 +64,13 @@ static void mode_tests(int fd)
>  static void framebuffer_tests(int fd)
>  {
>  	struct fb_fix_screeninfo fix_info;
> -	void * volatile map;
> -	void * volatile buf;
> +	unsigned char * volatile map;
> +	unsigned char * volatile buf;
> +	volatile size_t pagesize;
>  
>  	igt_fixture {
> +		long ret;
> +
>  		igt_require(ioctl(fd, FBIOGET_FSCREENINFO, &fix_info) == 0);
>  		igt_assert(fix_info.smem_len);
>  
> @@ -77,6 +80,10 @@ static void framebuffer_tests(int fd)
>  
>  		buf = malloc(fix_info.smem_len);
>  		igt_require(buf);
> +
> +		ret = sysconf(_SC_PAGESIZE);
> +		igt_require(ret != -1);
> +		pagesize = ret;
>  	}
>  
>  	igt_describe("Check read operations on framebuffer memory");
> @@ -99,6 +106,35 @@ static void framebuffer_tests(int fd)
>  		igt_assert_f(!cmp, "read buffer differs from mapped framebuffer for 0x55\n");
>  	}
>  
> +	igt_describe("Check read operations on unaligned locations in framebuffer memory");
> +	igt_subtest("unaligned-read") {
> +		off_t off;
> +		size_t len;
> +		ssize_t ret;
> +		const unsigned char *pos;
> +
> +		off = pagesize + (pagesize >> 2); // 1.25 * pagesize
> +		len = (pagesize << 2) + (pagesize >> 1); // 4.5 * pagesize
> +		igt_require_f((off + len) < fix_info.smem_len, "framebuffer too small to test\n");
> +
> +		/* read at unaligned location and compare */
> +		memset(map, 0, fix_info.smem_len);
> +		memset(&map[off], 0x55, len);
> +		memset(buf, 0xff, fix_info.smem_len);
> +		ret = pread(fd, &buf[off], len, off);
> +		igt_assert_f(ret == (ssize_t)len, "pread failed, ret=%zd\n", ret);
> +		pos = memchr(buf, 0x55, fix_info.smem_len);
> +		igt_assert_f(pos, "0x55 not found within read buffer\n");
> +		igt_assert_f(pos == &buf[off], "0x55 found at pos %zu, expected %lld\n",
> +			     pos - buf, (long long)off);
> +		pos = memchr(&buf[off], 0xff, fix_info.smem_len - off);
> +		igt_assert_f(pos, "0xff not found within read buffer\n");
> +		igt_assert_f(pos == &buf[off + len], "0xff found at pos %zu, expected %lld\n",
> +			     pos - buf, (long long)(off + len));
> +		pos = memchr(&buf[off + len], 0x55, fix_info.smem_len - off + len);
> +		igt_assert_f(pos, "found 0x55 at pos %zu, none expected\n", pos - buf);
> +	}
> +
>  	igt_fixture {
>  		free(buf);
>  		memset(map, 0, fix_info.smem_len); // don't leave garbage on the screen
> diff --git a/tests/intel-ci/fast-feedback.testlist b/tests/intel-ci/fast-feedback.testlist
> index fc8a605f..2f9148ab 100644
> --- a/tests/intel-ci/fast-feedback.testlist
> +++ b/tests/intel-ci/fast-feedback.testlist
> @@ -4,6 +4,7 @@ igt at core_auth@basic-auth
>  igt at debugfs_test@read_all_entries
>  igt at fbdev@info
>  igt at fbdev@read
> +igt at fbdev@unaligned-read

Leave this and unaligned-write out of
fast-feedback.testlist. Otherwise the CI changes look good.


-- 
Petri Latvala