Re: [PATCHv6 bpf-next 13/16] selftests/bpf: Add uprobe session single consumer test

[Andrii Nakryiko]

On Thu, Oct 10, 2024 at 1:12 PM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Testing that the session ret_handler bypass works on single
> uprobe with multiple consumers, each with different session
> ignore return value.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
>  .../bpf/prog_tests/uprobe_multi_test.c        | 33 ++++++++++++++
>  .../bpf/progs/uprobe_multi_session_single.c   | 44 +++++++++++++++++++
>  2 files changed, 77 insertions(+)
>  create mode 100644 tools/testing/selftests/bpf/progs/uprobe_multi_session_single.c
>

see the nit, but regardless:

Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>

[...]

> diff --git a/tools/testing/selftests/bpf/progs/uprobe_multi_session_single.c b/tools/testing/selftests/bpf/progs/uprobe_multi_session_single.c
> new file mode 100644
> index 000000000000..1fa53d3785f6
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/uprobe_multi_session_single.c
> @@ -0,0 +1,44 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <linux/bpf.h>
> +#include <bpf/bpf_helpers.h>
> +#include <bpf/bpf_tracing.h>
> +#include <stdbool.h>
> +#include "bpf_kfuncs.h"
> +#include "bpf_misc.h"
> +
> +char _license[] SEC("license") = "GPL";
> +
> +__u64 uprobe_session_result[3] = {};
> +int pid = 0;
> +
> +static int uprobe_multi_check(void *ctx, bool is_return, int idx)

nit: you don't use is_return

> +{
> +       if (bpf_get_current_pid_tgid() >> 32 != pid)
> +               return 1;
> +
> +       uprobe_session_result[idx]++;
> +
> +       /* only consumer 1 executes return probe */
> +       if (idx == 0 || idx == 2)
> +               return 1;
> +
> +       return 0;
> +}
> +
> +SEC("uprobe.session//proc/self/exe:uprobe_multi_func_1")
> +int uprobe_0(struct pt_regs *ctx)
> +{
> +       return uprobe_multi_check(ctx, bpf_session_is_return(), 0);
> +}
> +
> +SEC("uprobe.session//proc/self/exe:uprobe_multi_func_1")
> +int uprobe_1(struct pt_regs *ctx)
> +{
> +       return uprobe_multi_check(ctx, bpf_session_is_return(), 1);
> +}
> +
> +SEC("uprobe.session//proc/self/exe:uprobe_multi_func_1")
> +int uprobe_2(struct pt_regs *ctx)
> +{
> +       return uprobe_multi_check(ctx, bpf_session_is_return(), 2);
> +}
> --
> 2.46.2
>