On Thu, Nov 3, 2022 at 8:21 AM Yonghong Song <yhs@xxxxxx> wrote: > > Add a few positive/negative tests to test bpf_rcu_read_lock() > and its corresponding verifier support. > > ./test_progs -t rcu_read_lock > ... > #145/1 rcu_read_lock/local_storage:OK > #145/2 rcu_read_lock/runtime_diff_rcu_tag:OK > #145/3 rcu_read_lock/negative_tests:OK > #145 rcu_read_lock:OK > Summary: 1/3 PASSED, 0 SKIPPED, 0 FAILED > > Signed-off-by: Yonghong Song <yhs@xxxxxx> > --- > .../selftests/bpf/prog_tests/rcu_read_lock.c | 101 ++++++++ > .../selftests/bpf/progs/rcu_read_lock.c | 241 ++++++++++++++++++ > 2 files changed, 342 insertions(+) > create mode 100644 tools/testing/selftests/bpf/prog_tests/rcu_read_lock.c > create mode 100644 tools/testing/selftests/bpf/progs/rcu_read_lock.c > > diff --git a/tools/testing/selftests/bpf/prog_tests/rcu_read_lock.c b/tools/testing/selftests/bpf/prog_tests/rcu_read_lock.c > new file mode 100644 > index 000000000000..46c02bdb1360 > --- /dev/null > +++ b/tools/testing/selftests/bpf/prog_tests/rcu_read_lock.c > @@ -0,0 +1,101 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates.*/ > + > +#define _GNU_SOURCE > +#include <unistd.h> > +#include <sys/syscall.h> > +#include <sys/types.h> [...] > + > + task = bpf_get_current_task_btf(); > + > + bpf_rcu_read_lock(); > + real_parent = task->real_parent; > + bpf_rcu_read_unlock(); The tests are nice, It would be nice to add a comment on what actually is wrong. e.g. /* real_parent is accessed outside the RCU critical section */ > + (void)bpf_task_storage_get(&map_b, real_parent, 0, > + BPF_LOCAL_STORAGE_GET_F_CREATE); > + return 0; > +} > + [...] > + bpf_rcu_read_lock(); > + bkey = bpf_lookup_user_key(key_serial, flags); > + bpf_rcu_read_unlock(); > + if (!bkey) > + return -1; > + bpf_key_put(bkey); > + > + return 0; nit: Spaces here instead of tabs. > +} > -- > 2.30.2 >
