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References: <20220427210345.455611-1-jolsa@kernel.org> <20220427210345.455611-3-jolsa@kernel.org>
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From:   Andrii Nakryiko <andrii.nakryiko@gmail.com>
Date:   Wed, 27 Apr 2022 16:24:17 -0700
Message-ID: <CAEf4BzZBnWFxj44OwbNdHrV_LQz_2HmDUSHhEv69psrzi09egQ@mail.gmail.com>
Subject: Re: [PATCHv3 bpf-next 2/5] ftrace: Add ftrace_lookup_symbols function
To:     Jiri Olsa <jolsa@kernel.org>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Networking <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@chromium.org>,
        Steven Rostedt <rostedt@goodmis.org>
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On Wed, Apr 27, 2022 at 2:04 PM Jiri Olsa <jolsa@kernel.org> wrote:
>
> Adding ftrace_lookup_symbols function that resolves array of symbols
> with single pass over kallsyms.
>
> The user provides array of string pointers with count and pointer to
> allocated array for resolved values.
>
>   int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt,
>                             unsigned long *addrs)
>
> It iterates all kalsyms symbols and tries to loop up each in provided

typo: kallsyms

> symbols array with bsearch. The symbols array needs to be sorted by
> name for this reason.
>
> We also check each symbol to pass ftrace_location, because this API
> will be used for fprobe symbols resolving.
>
> Suggested-by: Andrii Nakryiko <andrii@kernel.org>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---

LGTM.

Acked-by: Andrii Nakryiko <andrii@kernel.org>

>  include/linux/ftrace.h |  6 ++++
>  kernel/kallsyms.c      |  1 +
>  kernel/trace/ftrace.c  | 62 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 69 insertions(+)
>

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