Re: [PATCH] v4l-compliance: re-introduce NON_COHERENT and cache hints tests

From: Hans Verkuil
Date: Fri Sep 10 2021 - 08:20:20 EST

Hi Sergey,

I've applied the "[PATCHv6 0/8] videobuf2: support new noncontiguous DMA API" series
to my kernel, and applied this patch to v4l-utils.

Running 'test-media vim2m' in contrib/test results in the following compliance failures:

Streaming ioctls:
test read/write: OK (Not Supported)
test blocking wait: OK
Video Capture: Captured 8 buffers
test MMAP (no poll): OK
Video Capture: Captured 8 buffers
test MMAP (select): OK
Video Capture: Captured 8 buffers
test MMAP (epoll): OK
Video Capture: Captured 8 buffers
test USERPTR (no poll): OK
Video Capture: Captured 8 buffers
test USERPTR (select): OK
fail: v4l2-test-buffers.cpp(1869): !(flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE)
fail: v4l2-test-buffers.cpp(1932): setupDmaBuf(expbuf_node, node, q, exp_q)
test DMABUF (no poll): FAIL
fail: v4l2-test-buffers.cpp(1869): !(flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE)
fail: v4l2-test-buffers.cpp(1932): setupDmaBuf(expbuf_node, node, q, exp_q)
test DMABUF (select): FAIL

The same happens with e.g. vivid, but vim2m is quicker to test.

I'm not sure whether this is a bug in this v4l2-compliance patch or whether it is
a bug in the v6 series, but it should be checked.

Regards,

Hans

On 09/07/2021 11:22, Sergey Senozhatsky wrote:
> This returns back non-coherent (previously known as NON_COHERENT)
> memory flag and buffer cache management hints testing (for VB2_MEMORY_MMAP
> buffers).
>
> Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
> ---
> utils/common/cv4l-helpers.h | 8 +--
> utils/common/v4l-helpers.h | 8 ++-
> utils/v4l2-compliance/v4l2-test-buffers.cpp | 65 ++++++++++++++++++---
> 3 files changed, 66 insertions(+), 15 deletions(-)
>
> diff --git a/utils/common/cv4l-helpers.h b/utils/common/cv4l-helpers.h
> index 712efde6..3cee372b 100644
> --- a/utils/common/cv4l-helpers.h
> +++ b/utils/common/cv4l-helpers.h
> @@ -754,17 +754,17 @@ public:
> int g_fd(unsigned index, unsigned plane) const { return v4l_queue_g_fd(this, index, plane); }
> void s_fd(unsigned index, unsigned plane, int fd) { v4l_queue_s_fd(this, index, plane, fd); }
>
> - int reqbufs(cv4l_fd *fd, unsigned count = 0)
> + int reqbufs(cv4l_fd *fd, unsigned count = 0, unsigned int flags = 0)
> {
> - return v4l_queue_reqbufs(fd->g_v4l_fd(), this, count);
> + return v4l_queue_reqbufs(fd->g_v4l_fd(), this, count, flags);
> }
> bool has_create_bufs(cv4l_fd *fd) const
> {
> return v4l_queue_has_create_bufs(fd->g_v4l_fd(), this);
> }
> - int create_bufs(cv4l_fd *fd, unsigned count, const v4l2_format *fmt = NULL)
> + int create_bufs(cv4l_fd *fd, unsigned count, const v4l2_format *fmt = NULL, unsigned int flags = 0)
> {
> - return v4l_queue_create_bufs(fd->g_v4l_fd(), this, count, fmt);
> + return v4l_queue_create_bufs(fd->g_v4l_fd(), this, count, fmt, flags);
> }
> int mmap_bufs(cv4l_fd *fd, unsigned from = 0)
> {
> diff --git a/utils/common/v4l-helpers.h b/utils/common/v4l-helpers.h
> index f96b3c38..c09cd987 100644
> --- a/utils/common/v4l-helpers.h
> +++ b/utils/common/v4l-helpers.h
> @@ -1515,7 +1515,7 @@ static inline int v4l_queue_querybufs(struct v4l_fd *f, struct v4l_queue *q, uns
> }
>
> static inline int v4l_queue_reqbufs(struct v4l_fd *f,
> - struct v4l_queue *q, unsigned count)
> + struct v4l_queue *q, unsigned count, unsigned int flags = 0)
> {
> struct v4l2_requestbuffers reqbufs;
> int ret;
> @@ -1523,6 +1523,7 @@ static inline int v4l_queue_reqbufs(struct v4l_fd *f,
> reqbufs.type = q->type;
> reqbufs.memory = q->memory;
> reqbufs.count = count;
> + reqbufs.flags = flags;
> /*
> * Problem: if REQBUFS returns an error, did it free any old
> * buffers or not?
> @@ -1547,7 +1548,7 @@ static inline bool v4l_queue_has_create_bufs(struct v4l_fd *f, const struct v4l_
>
> static inline int v4l_queue_create_bufs(struct v4l_fd *f,
> struct v4l_queue *q, unsigned count,
> - const struct v4l2_format *fmt)
> + const struct v4l2_format *fmt, unsigned int flags = 0)
> {
> struct v4l2_create_buffers createbufs;
> int ret;
> @@ -1555,6 +1556,7 @@ static inline int v4l_queue_create_bufs(struct v4l_fd *f,
> createbufs.format.type = q->type;
> createbufs.memory = q->memory;
> createbufs.count = count;
> + createbufs.flags = flags;
> if (fmt) {
> createbufs.format = *fmt;
> } else {
> @@ -1733,7 +1735,7 @@ static inline void v4l_queue_free(struct v4l_fd *f, struct v4l_queue *q)
> v4l_ioctl(f, VIDIOC_STREAMOFF, &q->type);
> v4l_queue_release_bufs(f, q, 0);
> v4l_queue_close_exported_fds(q);
> - v4l_queue_reqbufs(f, q, 0);
> + v4l_queue_reqbufs(f, q, 0, 0);
> }
>
> static inline void v4l_queue_buffer_update(const struct v4l_queue *q,
> diff --git a/utils/v4l2-compliance/v4l2-test-buffers.cpp b/utils/v4l2-compliance/v4l2-test-buffers.cpp
> index e40461bd..6997f40b 100644
> --- a/utils/v4l2-compliance/v4l2-test-buffers.cpp
> +++ b/utils/v4l2-compliance/v4l2-test-buffers.cpp
> @@ -663,6 +663,10 @@ int testReqBufs(struct node *node)
> fail_on_test(q.reqbufs(node, 0));
>
> for (m = V4L2_MEMORY_MMAP; m <= V4L2_MEMORY_DMABUF; m++) {
> + bool cache_hints_cap = false;
> + bool coherent;
> +
> + cache_hints_cap = q.g_capabilities() & V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS;
> if (!(node->valid_memorytype & (1 << m)))
> continue;
> cv4l_queue q2(i, m);
> @@ -678,8 +682,17 @@ int testReqBufs(struct node *node)
> reqbufs.count = 1;
> reqbufs.type = i;
> reqbufs.memory = m;
> + reqbufs.flags = V4L2_MEMORY_FLAG_NON_COHERENT;
> fail_on_test(doioctl(node, VIDIOC_REQBUFS, &reqbufs));
> - fail_on_test(check_0(reqbufs.reserved, sizeof(reqbufs.reserved)));
> + coherent = reqbufs.flags & V4L2_MEMORY_FLAG_NON_COHERENT;
> + if (!cache_hints_cap) {
> + fail_on_test(coherent);
> + } else {
> + if (m == V4L2_MEMORY_MMAP)
> + fail_on_test(!coherent);
> + else
> + fail_on_test(coherent);
> + }
> q.reqbufs(node);
>
> ret = q.create_bufs(node, 0);
> @@ -692,9 +705,32 @@ int testReqBufs(struct node *node)
> node->g_fmt(crbufs.format, i);
> crbufs.count = 1;
> crbufs.memory = m;
> + crbufs.flags = V4L2_MEMORY_FLAG_NON_COHERENT;
> fail_on_test(doioctl(node, VIDIOC_CREATE_BUFS, &crbufs));
> fail_on_test(check_0(crbufs.reserved, sizeof(crbufs.reserved)));
> fail_on_test(crbufs.index != q.g_buffers());
> +
> + coherent = crbufs.flags & V4L2_MEMORY_FLAG_NON_COHERENT;
> + if (!cache_hints_cap) {
> + fail_on_test(coherent);
> + } else {
> + if (m == V4L2_MEMORY_MMAP)
> + fail_on_test(!coherent);
> + else
> + fail_on_test(coherent);
> + }
> +
> + if (cache_hints_cap) {
> + /*
> + * Different memory consistency model. Should fail for MMAP
> + * queues which support cache hints.
> + */
> + crbufs.flags = 0;
> + if (m == V4L2_MEMORY_MMAP)
> + fail_on_test(doioctl(node, VIDIOC_CREATE_BUFS, &crbufs) != EINVAL);
> + else
> + fail_on_test(doioctl(node, VIDIOC_CREATE_BUFS, &crbufs));
> + }
> q.reqbufs(node);
>
> fail_on_test(q.create_bufs(node, 1));
> @@ -1207,10 +1243,16 @@ static int setupMmap(struct node *node, cv4l_queue &q)
> fail_on_test(buf.querybuf(node, i));
> fail_on_test(buf.check(q, Unqueued, i));
>
> - flags = buf.g_flags();
> - flags |= V4L2_BUF_FLAG_NO_CACHE_INVALIDATE;
> - flags |= V4L2_BUF_FLAG_NO_CACHE_CLEAN;
> - buf.s_flags(flags);
> + /*
> + * Do not set cache hints for all the buffers, but only on
> + * some of them, so that we can test more cases.
> + */
> + if (i == 0) {
> + flags = buf.g_flags();
> + flags |= V4L2_BUF_FLAG_NO_CACHE_INVALIDATE;
> + flags |= V4L2_BUF_FLAG_NO_CACHE_CLEAN;
> + buf.s_flags(flags);
> + }
>
> for (unsigned p = 0; p < buf.g_num_planes(); p++) {
> // Try a random offset
> @@ -1250,8 +1292,15 @@ static int setupMmap(struct node *node, cv4l_queue &q)
> }
> flags = buf.g_flags();
> if (cache_hints) {
> - fail_on_test(!(flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE));
> - fail_on_test(!(flags & V4L2_BUF_FLAG_NO_CACHE_CLEAN));
> + if (i == 0) {
> + /* We do expect cache hints on this buffer */
> + fail_on_test(!(flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE));
> + fail_on_test(!(flags & V4L2_BUF_FLAG_NO_CACHE_CLEAN));
> + } else {
> + /* We expect no cache hints on this buffer */
> + fail_on_test(flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE);
> + fail_on_test(flags & V4L2_BUF_FLAG_NO_CACHE_CLEAN);
> + }
> } else if (node->might_support_cache_hints) {
> fail_on_test(flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE);
> fail_on_test(flags & V4L2_BUF_FLAG_NO_CACHE_CLEAN);
> @@ -1341,7 +1390,7 @@ int testMmap(struct node *node, struct node *node_m2m_cap, unsigned frame_count,
> have_createbufs = false;
> if (have_createbufs) {
> q.reqbufs(node);
> - q.create_bufs(node, 2, &cur_fmt);
> + q.create_bufs(node, 2, &cur_fmt, V4L2_MEMORY_FLAG_NON_COHERENT);
> fail_on_test(setupMmap(node, q));
> q.munmap_bufs(node);
> q.reqbufs(node, 2);
>