[PATCH bpf-next v1 8/8] bpf/selftests: Test for bpf_per_cpu_ptr()
From: Hao Luo <hidden>
Date: 2020-08-19 22:41:38
Also in:
bpf, linux-kselftest, lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Linus Torvalds
Test bpf_per_cpu_ptr(). Test two paths in the kernel. If the base pointer points to a struct, the returned reg is of type PTR_TO_BTF_ID. Direct pointer dereference can be applied on the returned variable. If the base pointer isn't a struct, the returned reg is of type PTR_TO_MEM, which also supports direct pointer dereference. Signed-off-by: Hao Luo <redacted> --- .../testing/selftests/bpf/prog_tests/ksyms_btf.c | 4 ++++ .../testing/selftests/bpf/progs/test_ksyms_btf.c | 15 ++++++++++++++- 2 files changed, 18 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c b/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c
index 1dad61ba7e99..bdedd4a76b42 100644
--- a/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c@@ -71,6 +71,10 @@ void test_ksyms_btf(void) "got %llu, exp %llu\n", data->out__runqueues, runqueues_addr); CHECK(data->out__bpf_prog_active != bpf_prog_active_addr, "bpf_prog_active", "got %llu, exp %llu\n", data->out__bpf_prog_active, bpf_prog_active_addr); + CHECK(data->out__rq_cpu != 1, "rq_cpu", + "got %u, exp %u\n", data->out__rq_cpu, 1); + CHECK(data->out__process_counts == -1, "process_counts", + "got %lu, exp != -1", data->out__process_counts); cleanup: test_ksyms_btf__destroy(skel);
diff --git a/tools/testing/selftests/bpf/progs/test_ksyms_btf.c b/tools/testing/selftests/bpf/progs/test_ksyms_btf.c
index e04e31117f84..78cf1ebb753d 100644
--- a/tools/testing/selftests/bpf/progs/test_ksyms_btf.c
+++ b/tools/testing/selftests/bpf/progs/test_ksyms_btf.c@@ -7,16 +7,29 @@ __u64 out__runqueues = -1; __u64 out__bpf_prog_active = -1; +__u32 out__rq_cpu = -1; +unsigned long out__process_counts = -1; -extern const struct rq runqueues __ksym; /* struct type global var. */ +extern const struct rq runqueues __ksym; /* struct type percpu var. */ extern const int bpf_prog_active __ksym; /* int type global var. */ +extern const unsigned long process_counts __ksym; /* int type percpu var. */ SEC("raw_tp/sys_enter") int handler(const void *ctx) { + struct rq *rq; + unsigned long *count; + out__runqueues = (__u64)&runqueues; out__bpf_prog_active = (__u64)&bpf_prog_active; + rq = (struct rq *)bpf_per_cpu_ptr(&runqueues, 1); + if (rq) + out__rq_cpu = rq->cpu; + count = (unsigned long *)bpf_per_cpu_ptr(&process_counts, 1); + if (count) + out__process_counts = *count; + return 0; }
--
2.28.0.220.ged08abb693-goog