From: Steven Rostedt <rostedt@goodmis.org>
To: Michael Jeanson <mjeanson@efficios.com>
Cc: linux-kernel@vger.kernel.org,
Peter Zijlstra <peterz@infradead.org>,
Alexei Starovoitov <ast@kernel.org>, Yonghong Song <yhs@fb.com>,
"Paul E . McKenney" <paulmck@kernel.org>,
Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
Joel Fernandes <joel@joelfernandes.org>,
bpf@vger.kernel.org
Subject: Re: [RFC PATCH 0/6] [RFC] Faultable tracepoints (v2)
Date: Tue, 23 Feb 2021 21:16:39 -0500 [thread overview]
Message-ID: <20210223211639.670db85c@gandalf.local.home> (raw)
In-Reply-To: <20210218222125.46565-1-mjeanson@efficios.com>
On Thu, 18 Feb 2021 17:21:19 -0500
Michael Jeanson <mjeanson@efficios.com> wrote:
> This series only implements the tracepoint infrastructure required to
> allow tracers to handle page faults. Modifying each tracer to handle
> those page faults would be a next step after we all agree on this piece
> of instrumentation infrastructure.
I started taking a quick look at this, and came up with the question: how
do you allow preemption when dealing with per-cpu buffers or storage to
record the data?
That is, perf, bpf and ftrace are all using some kind of per-cpu data, and
this is the reason for the need to disable preemption. What's the solution
that LTTng is using for this? I know it has a per cpu buffers too, but does
it have some kind of "per task" buffer that is being used to extract the
data that can fault?
-- Steve
next prev parent reply other threads:[~2021-02-24 2:17 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-18 22:21 [RFC PATCH 0/6] [RFC] Faultable tracepoints (v2) Michael Jeanson
2021-02-18 22:21 ` [RFC PATCH 1/6] tracing: introduce faultable " Michael Jeanson
2021-02-18 22:21 ` [RFC PATCH 2/6] tracing: ftrace: add support for faultable tracepoints Michael Jeanson
2021-02-18 22:21 ` [RFC PATCH 3/6] tracing: bpf-trace: " Michael Jeanson
2021-02-18 22:21 ` [RFC PATCH 4/6] tracing: perf: " Michael Jeanson
2021-02-18 22:21 ` [RFC PATCH 5/6] tracing: convert sys_enter/exit to " Michael Jeanson
2021-02-18 22:21 ` [RFC PATCH 6/6] tracing: use Tasks Trace RCU instead of SRCU for rcuidle tracepoints Michael Jeanson
2021-02-24 2:16 ` Steven Rostedt [this message]
2021-02-24 16:22 ` [RFC PATCH 0/6] [RFC] Faultable tracepoints (v2) Michael Jeanson
2021-02-24 16:59 ` Mathieu Desnoyers
2021-02-24 18:14 ` Steven Rostedt
2021-02-25 21:46 ` Mathieu Desnoyers
2021-02-24 23:54 ` Mathieu Desnoyers
2021-02-26 5:28 ` Lai Jiangshan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210223211639.670db85c@gandalf.local.home \
--to=rostedt@goodmis.org \
--cc=acme@kernel.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=joel@joelfernandes.org \
--cc=jolsa@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mingo@redhat.com \
--cc=mjeanson@efficios.com \
--cc=namhyung@kernel.org \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=yhs@fb.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).