| Message ID | 20250508182025.2961555-6-tjmercier@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [bpf-next,v4,1/5] dma-buf: Rename debugfs symbols | expand |
On Fri, May 9, 2025 at 11:46 AM Song Liu <song@kernel.org> wrote: > > On Thu, May 8, 2025 at 11:21 AM T.J. Mercier <tjmercier@google.com> wrote: > > > > Use the same test buffers as the traditional iterator and a new BPF map > > to verify the test buffers can be found with the open coded dmabuf > > iterator. > > The way we split 4/5 and 5/5 makes the code tricker to follow. I guess > the motivation is to back port default iter along to older kernels. But I > think we can still make the code cleaner. > > > > > Signed-off-by: T.J. Mercier <tjmercier@google.com> > > --- > [...] > > > > > -static int create_udmabuf(void) > > +static int create_udmabuf(int map_fd) > > { > > struct udmabuf_create create; > > int dev_udmabuf; > > + bool f = false; > > > > udmabuf_test_buffer_size = 10 * getpagesize(); > > > > @@ -63,10 +64,10 @@ static int create_udmabuf(void) > > if (!ASSERT_OK(ioctl(udmabuf, DMA_BUF_SET_NAME_B, udmabuf_test_buffer_name), "name")) > > return 1; > > > > - return 0; > > + return bpf_map_update_elem(map_fd, udmabuf_test_buffer_name, &f, BPF_ANY); > > We don't really need this bpf_map_update_elem() inside > create_udmabuf(), right? > > > } > > > > -static int create_sys_heap_dmabuf(void) > > +static int create_sys_heap_dmabuf(int map_fd) > > { > > sysheap_test_buffer_size = 20 * getpagesize(); > > > > @@ -77,6 +78,7 @@ static int create_sys_heap_dmabuf(void) > > .heap_flags = 0, > > }; > > int heap_fd, ret; > > + bool f = false; > > > > if (!ASSERT_LE(sizeof(sysheap_test_buffer_name), DMA_BUF_NAME_LEN, "NAMETOOLONG")) > > return 1; > > @@ -95,18 +97,18 @@ static int create_sys_heap_dmabuf(void) > > if (!ASSERT_OK(ioctl(sysheap_dmabuf, DMA_BUF_SET_NAME_B, sysheap_test_buffer_name), "name")) > > return 1; > > > > - return 0; > > + return bpf_map_update_elem(map_fd, sysheap_test_buffer_name, &f, BPF_ANY); > > Same for this bpf_map_update_elem(), we can call this directly from > create_test_buffers(). > > > } > > > > -static int create_test_buffers(void) > > +static int create_test_buffers(int map_fd) > > { > > int ret; > > > > - ret = create_udmabuf(); > > + ret = create_udmabuf(map_fd); > > if (ret) > > return ret; > > > > - return create_sys_heap_dmabuf(); > > + return create_sys_heap_dmabuf(map_fd); > > Personally, I would prefer we just merge all the logic of > create_udmabuf() and create_sys_heap_dmabuf() > into create_test_buffers(). That's a lot of different stuff to put in one place. How about returning file descriptors from the buffer create functions while having them clean up after themselves: -static int memfd, udmabuf; +static int udmabuf; static const char udmabuf_test_buffer_name[DMA_BUF_NAME_LEN] = "udmabuf_test_buffer_for_iter"; static size_t udmabuf_test_buffer_size; static int sysheap_dmabuf; static const char sysheap_test_buffer_name[DMA_BUF_NAME_LEN] = "sysheap_test_buffer_for_iter"; static size_t sysheap_test_buffer_size; -static int create_udmabuf(int map_fd) +static int create_udmabuf(void) { struct udmabuf_create create; - int dev_udmabuf; - bool f = false; + int dev_udmabuf, memfd, udmabuf; udmabuf_test_buffer_size = 10 * getpagesize(); if (!ASSERT_LE(sizeof(udmabuf_test_buffer_name), DMA_BUF_NAME_LEN, "NAMETOOLONG")) - return 1; + return -1; memfd = memfd_create("memfd_test", MFD_ALLOW_SEALING); if (!ASSERT_OK_FD(memfd, "memfd_create")) - return 1; + return -1; if (!ASSERT_OK(ftruncate(memfd, udmabuf_test_buffer_size), "ftruncate")) - return 1; + goto close_memfd; if (!ASSERT_OK(fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK), "seal")) - return 1; + goto close_memfd; dev_udmabuf = open("/dev/udmabuf", O_RDONLY); if (!ASSERT_OK_FD(dev_udmabuf, "open udmabuf")) - return 1; + goto close_memfd; create.memfd = memfd; create.flags = UDMABUF_FLAGS_CLOEXEC; @@ -59,15 +58,21 @@ static int create_udmabuf(int map_fd) udmabuf = ioctl(dev_udmabuf, UDMABUF_CREATE, &create); close(dev_udmabuf); if (!ASSERT_OK_FD(udmabuf, "udmabuf_create")) - return 1; + goto close_memfd; if (!ASSERT_OK(ioctl(udmabuf, DMA_BUF_SET_NAME_B, udmabuf_test_buffer_name), "name")) - return 1; + goto close_udmabuf; + + return udmabuf; - return bpf_map_update_elem(map_fd, udmabuf_test_buffer_name, &f, BPF_ANY); +close_udmabuf: + close(udmabuf); +close_memfd: + close(memfd); + return -1; } -static int create_sys_heap_dmabuf(int map_fd) +static int create_sys_heap_dmabuf(void) { sysheap_test_buffer_size = 20 * getpagesize(); @@ -78,43 +83,46 @@ static int create_sys_heap_dmabuf(int map_fd) .heap_flags = 0, }; int heap_fd, ret; - bool f = false; if (!ASSERT_LE(sizeof(sysheap_test_buffer_name), DMA_BUF_NAME_LEN, "NAMETOOLONG")) - return 1; + return -1; heap_fd = open("/dev/dma_heap/system", O_RDONLY); if (!ASSERT_OK_FD(heap_fd, "open dma heap")) - return 1; + return -1; ret = ioctl(heap_fd, DMA_HEAP_IOCTL_ALLOC, &data); close(heap_fd); if (!ASSERT_OK(ret, "syheap alloc")) - return 1; + return -1; - sysheap_dmabuf = data.fd; + if (!ASSERT_OK(ioctl(data.fd, DMA_BUF_SET_NAME_B, sysheap_test_buffer_name), "name")) + goto close_sysheap_dmabuf; - if (!ASSERT_OK(ioctl(sysheap_dmabuf, DMA_BUF_SET_NAME_B, sysheap_test_buffer_name), "name")) - return 1; + return data.fd; - return bpf_map_update_elem(map_fd, sysheap_test_buffer_name, &f, BPF_ANY); +close_sysheap_dmabuf: + close(data.fd); + return -1; } static int create_test_buffers(int map_fd) { - int ret; + bool f = false; + + udmabuf = create_udmabuf(); + sysheap_dmabuf = create_sys_heap_dmabuf(); - ret = create_udmabuf(map_fd); - if (ret) - return ret; + if (udmabuf < 0 || sysheap_dmabuf < 0) + return -1; - return create_sys_heap_dmabuf(map_fd); + return bpf_map_update_elem(map_fd, udmabuf_test_buffer_name, &f, BPF_ANY) || + bpf_map_update_elem(map_fd, sysheap_test_buffer_name, &f, BPF_ANY); } static void destroy_test_buffers(void) { close(udmabuf); - close(memfd); close(sysheap_dmabuf); }
On Fri, May 9, 2025 at 2:43 PM T.J. Mercier <tjmercier@google.com> wrote: > [...] > > > > Personally, I would prefer we just merge all the logic of > > create_udmabuf() and create_sys_heap_dmabuf() > > into create_test_buffers(). > > That's a lot of different stuff to put in one place. How about > returning file descriptors from the buffer create functions while > having them clean up after themselves: I do like this version better. Some nitpicks though. > > -static int memfd, udmabuf; > +static int udmabuf; About this, and ... > static const char udmabuf_test_buffer_name[DMA_BUF_NAME_LEN] = > "udmabuf_test_buffer_for_iter"; > static size_t udmabuf_test_buffer_size; > static int sysheap_dmabuf; > static const char sysheap_test_buffer_name[DMA_BUF_NAME_LEN] = > "sysheap_test_buffer_for_iter"; > static size_t sysheap_test_buffer_size; > > -static int create_udmabuf(int map_fd) > +static int create_udmabuf(void) > { > struct udmabuf_create create; > - int dev_udmabuf; > - bool f = false; > + int dev_udmabuf, memfd, udmabuf; .. here. It is not ideal to have a global udmabuf and a local udmabuf. If we want the global version, let's rename the local one. [...] > > static int create_test_buffers(int map_fd) > { > - int ret; > + bool f = false; > + > + udmabuf = create_udmabuf(); > + sysheap_dmabuf = create_sys_heap_dmabuf(); > > - ret = create_udmabuf(map_fd); > - if (ret) > - return ret; > + if (udmabuf < 0 || sysheap_dmabuf < 0) > + return -1; We also need destroy_test_buffers() on the error path here, or at the caller. > > - return create_sys_heap_dmabuf(map_fd); > + return bpf_map_update_elem(map_fd, udmabuf_test_buffer_name, > &f, BPF_ANY) || > + bpf_map_update_elem(map_fd, sysheap_test_buffer_name, > &f, BPF_ANY); > } > > static void destroy_test_buffers(void) > { > close(udmabuf); > - close(memfd); > close(sysheap_dmabuf); For the two global fds, let's reset them to -1 right after close(). Thanks, Song
diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h index 6535c8ae3c46..5e512a1d09d1 100644 --- a/tools/testing/selftests/bpf/bpf_experimental.h +++ b/tools/testing/selftests/bpf/bpf_experimental.h @@ -591,4 +591,9 @@ extern int bpf_iter_kmem_cache_new(struct bpf_iter_kmem_cache *it) __weak __ksym extern struct kmem_cache *bpf_iter_kmem_cache_next(struct bpf_iter_kmem_cache *it) __weak __ksym; extern void bpf_iter_kmem_cache_destroy(struct bpf_iter_kmem_cache *it) __weak __ksym; +struct bpf_iter_dmabuf; +extern int bpf_iter_dmabuf_new(struct bpf_iter_dmabuf *it) __weak __ksym; +extern struct dma_buf *bpf_iter_dmabuf_next(struct bpf_iter_dmabuf *it) __weak __ksym; +extern void bpf_iter_dmabuf_destroy(struct bpf_iter_dmabuf *it) __weak __ksym; + #endif diff --git a/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c b/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c index 35745f4ce0f8..c8230a080ef3 100644 --- a/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c @@ -26,10 +26,11 @@ static int sysheap_dmabuf; static const char sysheap_test_buffer_name[DMA_BUF_NAME_LEN] = "sysheap_test_buffer_for_iter"; static size_t sysheap_test_buffer_size; -static int create_udmabuf(void) +static int create_udmabuf(int map_fd) { struct udmabuf_create create; int dev_udmabuf; + bool f = false; udmabuf_test_buffer_size = 10 * getpagesize(); @@ -63,10 +64,10 @@ static int create_udmabuf(void) if (!ASSERT_OK(ioctl(udmabuf, DMA_BUF_SET_NAME_B, udmabuf_test_buffer_name), "name")) return 1; - return 0; + return bpf_map_update_elem(map_fd, udmabuf_test_buffer_name, &f, BPF_ANY); } -static int create_sys_heap_dmabuf(void) +static int create_sys_heap_dmabuf(int map_fd) { sysheap_test_buffer_size = 20 * getpagesize(); @@ -77,6 +78,7 @@ static int create_sys_heap_dmabuf(void) .heap_flags = 0, }; int heap_fd, ret; + bool f = false; if (!ASSERT_LE(sizeof(sysheap_test_buffer_name), DMA_BUF_NAME_LEN, "NAMETOOLONG")) return 1; @@ -95,18 +97,18 @@ static int create_sys_heap_dmabuf(void) if (!ASSERT_OK(ioctl(sysheap_dmabuf, DMA_BUF_SET_NAME_B, sysheap_test_buffer_name), "name")) return 1; - return 0; + return bpf_map_update_elem(map_fd, sysheap_test_buffer_name, &f, BPF_ANY); } -static int create_test_buffers(void) +static int create_test_buffers(int map_fd) { int ret; - ret = create_udmabuf(); + ret = create_udmabuf(map_fd); if (ret) return ret; - return create_sys_heap_dmabuf(); + return create_sys_heap_dmabuf(map_fd); } static void destroy_test_buffers(void) @@ -187,17 +189,46 @@ static void subtest_dmabuf_iter_check_default_iter(struct dmabuf_iter *skel) close(iter_fd); } +static void subtest_dmabuf_iter_check_open_coded(struct dmabuf_iter *skel, int map_fd) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + char key[DMA_BUF_NAME_LEN]; + int err, fd; + bool found; + + /* No need to attach it, just run it directly */ + fd = bpf_program__fd(skel->progs.iter_dmabuf_for_each); + + err = bpf_prog_test_run_opts(fd, &topts); + if (!ASSERT_OK(err, "test_run_opts err")) + return; + if (!ASSERT_OK(topts.retval, "test_run_opts retval")) + return; + + if (!ASSERT_OK(bpf_map_get_next_key(map_fd, NULL, key), "get next key")) + return; + + do { + ASSERT_OK(bpf_map_lookup_elem(map_fd, key, &found), "lookup"); + ASSERT_TRUE(found, "found test buffer"); + } while (bpf_map_get_next_key(map_fd, key, key)); +} + void test_dmabuf_iter(void) { struct dmabuf_iter *skel = NULL; + int iter_fd, map_fd; char buf[256]; - int iter_fd; skel = dmabuf_iter__open_and_load(); if (!ASSERT_OK_PTR(skel, "dmabuf_iter__open_and_load")) return; - if (!ASSERT_OK(create_test_buffers(), "create_buffers")) + map_fd = bpf_map__fd(skel->maps.testbuf_hash); + if (!ASSERT_OK_FD(map_fd, "map_fd")) + goto destroy_skel; + + if (!ASSERT_OK(create_test_buffers(map_fd), "create_buffers")) goto destroy; if (!ASSERT_OK(dmabuf_iter__attach(skel), "skel_attach")) @@ -215,10 +246,13 @@ void test_dmabuf_iter(void) if (test__start_subtest("default_iter")) subtest_dmabuf_iter_check_default_iter(skel); + if (test__start_subtest("open_coded")) + subtest_dmabuf_iter_check_open_coded(skel, map_fd); close(iter_fd); destroy: destroy_test_buffers(); +destroy_skel: dmabuf_iter__destroy(skel); } diff --git a/tools/testing/selftests/bpf/progs/dmabuf_iter.c b/tools/testing/selftests/bpf/progs/dmabuf_iter.c index d654b4f64cfa..cfdcf4b1c636 100644 --- a/tools/testing/selftests/bpf/progs/dmabuf_iter.c +++ b/tools/testing/selftests/bpf/progs/dmabuf_iter.c @@ -9,6 +9,13 @@ char _license[] SEC("license") = "GPL"; +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(key_size, DMA_BUF_NAME_LEN); + __type(value, bool); + __uint(max_entries, 5); +} testbuf_hash SEC(".maps"); + /* * Fields output by this iterator are delimited by newlines. Convert any * newlines in user-provided printed strings to spaces. @@ -51,3 +58,34 @@ int dmabuf_collector(struct bpf_iter__dmabuf *ctx) BPF_SEQ_PRINTF(seq, "%lu\n%llu\n%s\n%s\n", inode, size, name, exporter); return 0; } + +SEC("syscall") +int iter_dmabuf_for_each(const void *ctx) +{ + struct dma_buf *d; + + bpf_for_each(dmabuf, d) { + char name[DMA_BUF_NAME_LEN]; + const char *pname; + bool *found; + + if (bpf_core_read(&pname, sizeof(pname), &d->name)) + return 1; + + /* Buffers are not required to be named */ + if (!pname) + continue; + + if (bpf_probe_read_kernel(name, sizeof(name), pname)) + return 1; + + found = bpf_map_lookup_elem(&testbuf_hash, name); + if (found) { + bool t = true; + + bpf_map_update_elem(&testbuf_hash, name, &t, BPF_EXIST); + } + } + + return 0; +}
Use the same test buffers as the traditional iterator and a new BPF map to verify the test buffers can be found with the open coded dmabuf iterator. Signed-off-by: T.J. Mercier <tjmercier@google.com> --- .../testing/selftests/bpf/bpf_experimental.h | 5 ++ .../selftests/bpf/prog_tests/dmabuf_iter.c | 52 +++++++++++++++---- .../testing/selftests/bpf/progs/dmabuf_iter.c | 38 ++++++++++++++ 3 files changed, 86 insertions(+), 9 deletions(-)