linux-kernel - Re: [PATCH v4 1/5] tracing: Introduce faultable tracepoints

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20231121110753.41dc5603@gandalf.local.home>
Date:   Tue, 21 Nov 2023 11:07:53 -0500
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        "Paul E. McKenney" <paulmck@...nel.org>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        linux-kernel@...r.kernel.org,
        Michael Jeanson <mjeanson@...icios.com>,
        Alexei Starovoitov <ast@...nel.org>,
        Yonghong Song <yhs@...com>, Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Jiri Olsa <jolsa@...hat.com>,
        Namhyung Kim <namhyung@...nel.org>, bpf@...r.kernel.org,
        Joel Fernandes <joel@...lfernandes.org>
Subject: Re: [PATCH v4 1/5] tracing: Introduce faultable tracepoints

On Tue, 21 Nov 2023 11:00:13 -0500
Mathieu Desnoyers <mathieu.desnoyers@...icios.com> wrote:

> > tasks-tracing-rcu:
> >    extention of tasks to have critical-sections ? Should this simply be
> >    tasks?  
> 
> tasks-trace-rcu is meant to allow tasks to block/take a page fault 
> within the read-side. It is specialized for tracing and has a single 
> domain. It does not need the smp_mb on the read-side, which makes it 
> lower-overhead than SRCU.

IOW, task-trace-rcu allows the call to schedule in its critical section,
whereas task-rcu does not?

-- Steve