Re: [PATCH 0/6] enable creating [k,u]probe with perf_event_open

From: Alexei Starovoitov
Date: Wed Nov 22 2017 - 00:01:05 EST

On Wed, Nov 15, 2017 at 09:23:31AM -0800, Song Liu wrote:
> Changes RFC v2 to PATCH v1:
> Check type PERF_TYPE_PROBE in perf_event_set_filter().
> Rebase on to tip perf/core.
> Changes RFC v1 to RFC v2:
> Fix build issue reported by kbuild test bot by adding ifdef of
> RFC v1 cover letter:
> This is to follow up the discussion over "new kprobe api" at Linux
> Plumbers 2017:
> With current kernel, user space tools can only create/destroy [k,u]probes
> with a text-based API (kprobe_events and uprobe_events in tracefs). This
> approach relies on user space to clean up the [k,u]probe after using them.
> However, this is not easy for user space to clean up properly.
> To solve this problem, we introduce a file descriptor based API.
> Specifically, we extended perf_event_open to create [k,u]probe, and attach
> this [k,u]probe to the file descriptor created by perf_event_open. These
> [k,u]probe are associated with this file descriptor, so they are not
> available in tracefs.

Peter, Ingo,
could you please review the proposed perf_event_open api extension?