veristat: add -t flag for adding BPF_F_TEST_STATE_FREQ program flag

Sometimes during debugging it's important that BPF program is loaded
with BPF_F_TEST_STATE_FREQ flag set to force verifier to do frequent
state checkpointing. Teach veristat to do this when -t ("test state")
flag is specified.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230505043317.3629845-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/veristat.c b/tools/testing/selftests/bpf/veristat.c
index 1db7185181dabba8fa9bfa3f9f5ed599dc7d3f11..655095810d4a12a9467abd495b351f1ac6e55a84 100644 (file)
--- a/tools/testing/selftests/bpf/veristat.c
+++ b/tools/testing/selftests/bpf/veristat.c
@@ -141,6 +141,7 @@ static struct env {
        bool verbose;
        bool debug;
        bool quiet;
+       bool force_checkpoints;
        enum resfmt out_fmt;
        bool show_version;
        bool comparison_mode;
@@ -209,6 +210,8 @@ static const struct argp_option opts[] = {
        { "log-level", 'l', "LEVEL", 0, "Verifier log level (default 0 for normal mode, 1 for verbose mode)" },
        { "log-fixed", OPT_LOG_FIXED, NULL, 0, "Disable verifier log rotation" },
        { "log-size", OPT_LOG_SIZE, "BYTES", 0, "Customize verifier log size (default to 16MB)" },
+       { "test-states", 't', NULL, 0,
+         "Force frequent BPF verifier state checkpointing (set BPF_F_TEST_STATE_FREQ program flag)" },
        { "quiet", 'q', NULL, 0, "Quiet mode" },
        { "emit", 'e', "SPEC", 0, "Specify stats to be emitted" },
        { "sort", 's', "SPEC", 0, "Specify sort order" },
@@ -284,6 +287,9 @@ static error_t parse_arg(int key, char *arg, struct argp_state *state)
                        argp_usage(state);
                }
                break;
+       case 't':
+               env.force_checkpoints = true;
+               break;
        case 'C':
                env.comparison_mode = true;
                break;
@@ -989,6 +995,9 @@ static int process_prog(const char *filename, struct bpf_object *obj, struct bpf
        /* increase chances of successful BPF object loading */
        fixup_obj(obj, prog, base_filename);
 
+       if (env.force_checkpoints)
+               bpf_program__set_flags(prog, bpf_program__flags(prog) | BPF_F_TEST_STATE_FREQ);
+
        err = bpf_object__load(obj);
        env.progs_processed++;