From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758132AbaFSQI2 (ORCPT ); Thu, 19 Jun 2014 12:08:28 -0400 Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.227]:50726 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757952AbaFSQI1 (ORCPT ); Thu, 19 Jun 2014 12:08:27 -0400 Date: Thu, 19 Jun 2014 12:08:24 -0400 From: Steven Rostedt To: Oleg Nesterov Cc: kbuild test robot , kbuild-all@01.org, LKML , Tyler Hicks , ecryptfs@vger.kernel.org Subject: Re: [trace:ftrace/core 1/3] include/trace/syscall.h:39:6: error: 'TIF_SYSCALL_TRACEPOINT' undeclared Message-ID: <20140619120824.1fed4b2f@gandalf.local.home> In-Reply-To: <20140619155108.GA15883@redhat.com> References: <53a1e7ba.ZIiv6DbOB78b9RzY%fengguang.wu@intel.com> <20140618211559.76bdea15@gandalf.local.home> <20140618211737.719fcf49@gandalf.local.home> <20140618213833.731d5fc4@gandalf.local.home> <20140619150300.GA7215@redhat.com> <20140619112635.41412408@gandalf.local.home> <20140619155108.GA15883@redhat.com> X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.23; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-RR-Connecting-IP: 107.14.168.142:25 X-Cloudmark-Score: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 19 Jun 2014 17:51:08 +0200 Oleg Nesterov wrote: > Please tell me if I should another "[PATCH]" email or resend 2-3 as well. > Sorry for inconvenience. This is fine. I'm going to do what I seldom do and rebase my for-next branch with this one instead. But first I'll run this through my cross-compile tests. I should have done that the fist time :-/ -- Steve > > ------------------------------------------------------------------------------- > Subject: [PATCH] tracing: Fix syscall_*regfunc() vs copy_process() race > > syscall_regfunc() and syscall_unregfunc() should set/clear > TIF_SYSCALL_TRACEPOINT system-wide, but do_each_thread() can race > with copy_process() and miss the new child which was not added to > the process/thread lists yet. > > Change copy_process() to update the child's TIF_SYSCALL_TRACEPOINT > under tasklist. > > Link: http://lkml.kernel.org/p/20140413185854.GB20668@redhat.com > > Cc: stable@vger.kernel.org # 2.6.33 > Fixes: a871bd33a6c0 "tracing: Add syscall tracepoints" > Acked-by: Frederic Weisbecker > Signed-off-by: Oleg Nesterov > --- > include/trace/syscall.h | 15 +++++++++++++++ > kernel/fork.c | 2 ++ > 2 files changed, 17 insertions(+), 0 deletions(-) > > diff --git a/include/trace/syscall.h b/include/trace/syscall.h > index fed853f..9674145 100644 > --- a/include/trace/syscall.h > +++ b/include/trace/syscall.h > @@ -4,6 +4,7 @@ > #include > #include > #include > +#include > > #include > > @@ -32,4 +33,18 @@ struct syscall_metadata { > struct ftrace_event_call *exit_event; > }; > > +#if defined(CONFIG_TRACEPOINTS) && defined(CONFIG_HAVE_SYSCALL_TRACEPOINTS) > +static inline void syscall_tracepoint_update(struct task_struct *p) > +{ > + if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) > + set_tsk_thread_flag(p, TIF_SYSCALL_TRACEPOINT); > + else > + clear_tsk_thread_flag(p, TIF_SYSCALL_TRACEPOINT); > +} > +#else > +static inline void syscall_tracepoint_update(struct task_struct *p) > +{ > +} > +#endif > + > #endif /* _TRACE_SYSCALL_H */ > diff --git a/kernel/fork.c b/kernel/fork.c > index cafea61..f7417f5 100644 > --- a/kernel/fork.c > +++ b/kernel/fork.c > @@ -1485,7 +1485,9 @@ static struct task_struct *copy_process(unsigned long clone_flags, > > total_forks++; > spin_unlock(¤t->sighand->siglock); > + syscall_tracepoint_update(p); > write_unlock_irq(&tasklist_lock); > + > proc_fork_connector(p); > cgroup_post_fork(p); > if (clone_flags & CLONE_THREAD)