Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752660Ab1DSN66 (ORCPT ); Tue, 19 Apr 2011 09:58:58 -0400 Received: from casper.infradead.org ([85.118.1.10]:36498 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752461Ab1DSN65 convert rfc822-to-8bit (ORCPT ); Tue, 19 Apr 2011 09:58:57 -0400 Subject: Re: [PATCH v3 2.6.39-rc1-tip 18/26] 18: uprobes: commonly used filters. From: Peter Zijlstra To: Srikar Dronamraju Cc: Ingo Molnar , Steven Rostedt , Linux-mm , Arnaldo Carvalho de Melo , Linus Torvalds , Jonathan Corbet , Christoph Hellwig , Masami Hiramatsu , Thomas Gleixner , Ananth N Mavinakayanahalli , Oleg Nesterov , Andrew Morton , SystemTap , Jim Keniston , Roland McGrath , Andi Kleen , LKML In-Reply-To: <20110401143602.15455.82211.sendpatchset@localhost6.localdomain6> References: <20110401143223.15455.19844.sendpatchset@localhost6.localdomain6> <20110401143602.15455.82211.sendpatchset@localhost6.localdomain6> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Tue, 19 Apr 2011 15:57:57 +0200 Message-ID: <1303221477.8345.6.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2989 Lines: 100 On Fri, 2011-04-01 at 20:06 +0530, Srikar Dronamraju wrote: > Provides most commonly used filters that most users of uprobes can > reuse. However this would be useful once we can dynamically associate a > filter with a uprobe-event tracer. > > Signed-off-by: Srikar Dronamraju > --- > include/linux/uprobes.h | 5 +++++ > kernel/uprobes.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 55 insertions(+), 0 deletions(-) > > diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h > index 26c4d78..34b989f 100644 > --- a/include/linux/uprobes.h > +++ b/include/linux/uprobes.h > @@ -65,6 +65,11 @@ struct uprobe_consumer { > struct uprobe_consumer *next; > }; > > +struct uprobe_simple_consumer { > + struct uprobe_consumer consumer; > + pid_t fvalue; > +}; > + > struct uprobe { > struct rb_node rb_node; /* node in the rb tree */ > atomic_t ref; > diff --git a/kernel/uprobes.c b/kernel/uprobes.c > index cdd52d0..c950f13 100644 > --- a/kernel/uprobes.c > +++ b/kernel/uprobes.c > @@ -1389,6 +1389,56 @@ int uprobe_post_notifier(struct pt_regs *regs) > return 0; > } > > +bool uprobes_pid_filter(struct uprobe_consumer *self, struct task_struct *t) > +{ > + struct uprobe_simple_consumer *usc; > + > + usc = container_of(self, struct uprobe_simple_consumer, consumer); > + if (t->tgid == usc->fvalue) > + return true; > + return false; > +} > + > +bool uprobes_tid_filter(struct uprobe_consumer *self, struct task_struct *t) > +{ > + struct uprobe_simple_consumer *usc; > + > + usc = container_of(self, struct uprobe_simple_consumer, consumer); > + if (t->pid == usc->fvalue) > + return true; > + return false; > +} Pretty much everything using t->pid/t->tgid is doing it wrong. > +bool uprobes_ppid_filter(struct uprobe_consumer *self, struct task_struct *t) > +{ > + pid_t pid; > + struct uprobe_simple_consumer *usc; > + > + usc = container_of(self, struct uprobe_simple_consumer, consumer); > + rcu_read_lock(); > + pid = task_tgid_vnr(t->real_parent); > + rcu_read_unlock(); > + > + if (pid == usc->fvalue) > + return true; > + return false; > +} > + > +bool uprobes_sid_filter(struct uprobe_consumer *self, struct task_struct *t) > +{ > + pid_t pid; > + struct uprobe_simple_consumer *usc; > + > + usc = container_of(self, struct uprobe_simple_consumer, consumer); > + rcu_read_lock(); > + pid = pid_vnr(task_session(t)); > + rcu_read_unlock(); > + > + if (pid == usc->fvalue) > + return true; > + return false; > +} And there things go haywire too. What you want is to save the pid-namespace of the task creating the filter in your uprobe_simple_consumer and use that to obtain the task's pid for matching with the provided number. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/