From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id E36468D003B for ; Tue, 19 Apr 2011 09:58:29 -0400 (EDT) Subject: Re: [PATCH v3 2.6.39-rc1-tip 18/26] 18: uprobes: commonly used filters. From: Peter Zijlstra 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: quoted-printable Date: Tue, 19 Apr 2011 15:57:57 +0200 Message-ID: <1303221477.8345.6.camel@twins> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: 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 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. >=20 > Signed-off-by: Srikar Dronamraju > --- > include/linux/uprobes.h | 5 +++++ > kernel/uprobes.c | 50 +++++++++++++++++++++++++++++++++++++++++= ++++++ > 2 files changed, 55 insertions(+), 0 deletions(-) >=20 > 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; > }; > =20 > +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; > } > =20 > +bool uprobes_pid_filter(struct uprobe_consumer *self, struct task_struct= *t) > +{ > + struct uprobe_simple_consumer *usc; > + > + usc =3D container_of(self, struct uprobe_simple_consumer, consumer); > + if (t->tgid =3D=3D usc->fvalue) > + return true; > + return false; > +} > + > +bool uprobes_tid_filter(struct uprobe_consumer *self, struct task_struct= *t) > +{ > + struct uprobe_simple_consumer *usc; > + > + usc =3D container_of(self, struct uprobe_simple_consumer, consumer); > + if (t->pid =3D=3D 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_struc= t *t) > +{ > + pid_t pid; > + struct uprobe_simple_consumer *usc; > + > + usc =3D container_of(self, struct uprobe_simple_consumer, consumer); > + rcu_read_lock(); > + pid =3D task_tgid_vnr(t->real_parent); > + rcu_read_unlock(); > + > + if (pid =3D=3D 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 =3D container_of(self, struct uprobe_simple_consumer, consumer); > + rcu_read_lock(); > + pid =3D pid_vnr(task_session(t)); > + rcu_read_unlock(); > + > + if (pid =3D=3D 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org