From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <systemtap-return-17822-listarch-systemtap=sources.redhat.com@sourceware.org>
Received: (qmail 20550 invoked by alias); 19 Apr 2011 13:40:18 -0000
Received: (qmail 20514 invoked by uid 22791); 19 Apr 2011 13:40:17 -0000
X-SWARE-Spam-Status: No, hits=-3.1 required=5.0	tests=AWL,BAYES_00,T_RP_MATCHES_RCVD
X-Spam-Check-By: sourceware.org
Received: from casper.infradead.org (HELO casper.infradead.org) (85.118.1.10)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 19 Apr 2011 13:40:00 +0000
Received: from j77219.upc-j.chello.nl ([24.132.77.219] helo=twins)	by casper.infradead.org with esmtpsa (Exim 4.72 #1 (Red Hat Linux))	id 1QCB9c-0002Hz-T8; Tue, 19 Apr 2011 13:39:44 +0000
Received: by twins (Postfix, from userid 1000)	id 7C3A184ED693; Tue, 19 Apr 2011 15:39:19 +0200 (CEST)
Subject: Re: [PATCH v3 2.6.39-rc1-tip 15/26] 15: uprobes: Handing int3 and singlestep exception.
From: Peter Zijlstra <peterz@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>, Linux-mm <linux-mm@kvack.org>, Arnaldo Carvalho de Melo <acme@infradead.org>, Linus Torvalds <torvalds@linux-foundation.org>, Jonathan Corbet <corbet@lwn.net>, Christoph Hellwig <hch@infradead.org>, Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,  Thomas Gleixner <tglx@linutronix.de>, Ananth N Mavinakayanahalli <ananth@in.ibm.com>, Oleg Nesterov <oleg@redhat.com>, LKML <linux-kernel@vger.kernel.org>, SystemTap <systemtap@sources.redhat.com>, Jim Keniston <jkenisto@linux.vnet.ibm.com>, Roland McGrath <roland@hack.frob.com>, Andi Kleen <andi@firstfloor.org>, Andrew Morton <akpm@linux-foundation.org>
In-Reply-To: <20110401143527.15455.32854.sendpatchset@localhost6.localdomain6>
References:	 <20110401143223.15455.19844.sendpatchset@localhost6.localdomain6>	 <20110401143527.15455.32854.sendpatchset@localhost6.localdomain6>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Date: Tue, 19 Apr 2011 13:40:00 -0000
Message-ID: <1303220359.8345.1.camel@twins>
Mime-Version: 1.0
Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <systemtap.sourceware.org>
List-Subscribe: <mailto:systemtap-subscribe@sourceware.org>
List-Post: <mailto:systemtap@sourceware.org>
List-Help: <mailto:systemtap-help@sourceware.org>, <http://sourceware.org/lists.html#faqs>
Sender: systemtap-owner@sourceware.org
X-SW-Source: 2011-q2/txt/msg00114.txt.bz2

On Fri, 2011-04-01 at 20:05 +0530, Srikar Dronamraju wrote:
> +               probept =3D uprobes_get_bkpt_addr(regs);
> +               down_read(&mm->mmap_sem);
> +               for (vma =3D mm->mmap; vma; vma =3D vma->vm_next) {
> +                       if (!valid_vma(vma))
> +                               continue;
> +                       if (probept < vma->vm_start || probept > vma->vm_=
end)
> +                               continue;
> +                       u =3D find_uprobe(vma->vm_file->f_mapping->host,
> +                                       probept - vma->vm_start);
> +                       break;
> +               }

Why the linear vma walk? Surely the find_vma() suffices since there can
only be one vma that matches a particular vaddr.

> +               up_read(&mm->mmap_sem);=20