linux-kernel - Re: [PATCH] sched/tracing: append prev

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20220510103152.68b8b66d@gandalf.local.home>
Date:   Tue, 10 May 2022 10:31:52 -0400
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     Andrii Nakryiko <andrii.nakryiko@...il.com>,
        Qais Yousef <qais.yousef@....com>,
        Alexei Starovoitov <alexei.starovoitov@...il.com>,
        Delyan Kratunov <delyank@...com>,
        Namhyung Kim <namhyung@...nel.org>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        "bigeasy@...utronix.de" <bigeasy@...utronix.de>,
        "dietmar.eggemann@....com" <dietmar.eggemann@....com>,
        "keescook@...omium.org" <keescook@...omium.org>,
        "x86@...nel.org" <x86@...nel.org>,
        "andrii@...nel.org" <andrii@...nel.org>,
        "u.kleine-koenig@...gutronix.de" <u.kleine-koenig@...gutronix.de>,
        "vincent.guittot@...aro.org" <vincent.guittot@...aro.org>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
        "mingo@...nel.org" <mingo@...nel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "rdunlap@...radead.org" <rdunlap@...radead.org>,
        "Kenta.Tada@...y.com" <Kenta.Tada@...y.com>,
        "tglx@...utronix.de" <tglx@...utronix.de>,
        "bristot@...hat.com" <bristot@...hat.com>,
        "ebiederm@...ssion.com" <ebiederm@...ssion.com>,
        "ast@...nel.org" <ast@...nel.org>,
        "legion@...nel.org" <legion@...nel.org>,
        "adharmap@...cinc.com" <adharmap@...cinc.com>,
        "valentin.schneider@....com" <valentin.schneider@....com>,
        "ed.tsai@...iatek.com" <ed.tsai@...iatek.com>,
        "juri.lelli@...hat.com" <juri.lelli@...hat.com>
Subject: Re: [PATCH] sched/tracing: append prev_state to tp args instead

On Tue, 10 May 2022 10:29:40 +0200
Peter Zijlstra <peterz@...radead.org> wrote:

> On Tue, May 10, 2022 at 09:01:22AM +0200, Peter Zijlstra wrote:
> > On Mon, May 09, 2022 at 12:32:31PM -0700, Andrii Nakryiko wrote:  
> > > So can this patch be applied, please, or it's a hard no?  
> > 
> > Sorry; I got distracted with other work. I'll grudingly apply the patch.  
> 
>   gcc-11-i386-allmodconfig [15:35]  FAILED
>   | In file included from ../include/trace/define_custom_trace.h:55,
>   |                  from ../samples/trace_events/trace_custom_sched.h:96,
>   |                  from ../samples/trace_events/trace_custom_sched.c:24:
>   | ../samples/trace_events/./trace_custom_sched.h: In function ‘ftrace_test_custom_probe_sched_switch’:
>   | ../include/trace/trace_custom_events.h:178:42: error: passing argument 1 of ‘check_trace_callback_type_sched_switch’ from incompatible pointer type [-Werror=incompatible-pointer-types]
>   |   178 |         check_trace_callback_type_##call(trace_custom_event_raw_event_##template); \
>   |       |                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>   |       |                                          |
>   |       |                                          void (*)(void *, bool,  unsigned int,  struct task_struct *, struct task_struct *) {aka void (*)(void *, _Bool,  unsigned int,  struct task_struct *, struct task_struct *)}
>   | ../include/trace/trace_custom_events.h:34:9: note: in expansion of macro ‘DEFINE_CUSTOM_EVENT’
>   |    34 |         DEFINE_CUSTOM_EVENT(name, name, PARAMS(proto), PARAMS(args));


Yes, the custom tracepoint sample code uses the sched_switch tracepoint as
an example. That sample code needs to be updated:

In samples/trace_events/trace_custom_sched.h:

TRACE_CUSTOM_EVENT(sched_switch,

        /*
         * The TP_PROTO() and TP_ARGS must match the trace event
         * that the custom event is using.
         */
        TP_PROTO(bool preempt,
                 unsigned int prev_state,
                 struct task_struct *prev,
                 struct task_struct *next),

        TP_ARGS(preempt, prev_state, prev, next),



The arguments need to be updated.

-- Steve