Re: [PATCH v1 0/3] perf probe: Support long symbol
From: Namhyung Kim
Date: Wed Oct 09 2024 - 21:13:01 EST
Hello Leo,
On Mon, Oct 07, 2024 at 03:11:13PM +0100, Leo Yan wrote:
> Currently, a probe supports event name maximum to a 64-byte length. The
> event name comes from the probed symbol name, otherwise, user can
> specify an event name.
>
> In the case when user tries to inject a probe for a long symbol, e.g.
> mangled symbol name in a C++ program, the kernel buffer cannot
> accommodate it if the symbol name is longer than 64 bytes.
>
> On the other hand, this series relies on the perf tool to resolve the
> issue. When the tool detects user doesn't specify event name and the
> probed symbol is longer than 64 bytes, it will generate a hashed event
> name with 64-byte length to avoid failure.
Please CC Masami for probe related changes in the future.
Thanks,
Namhyung
>
>
> Leo Yan (3):
> perf: Dynamically allocate buffer for event string
> perf probe: Check group string length
> perf probe: Generate hash event for long symbol
>
> tools/perf/util/probe-event.c | 71 ++++++++++++++++++++++++++++++++---
> 1 file changed, 65 insertions(+), 6 deletions(-)
>
> --
> 2.34.1
>