From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 27EAF6007F9 for ; Tue, 27 Jul 2010 07:17:07 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail6.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o6RBH4cU027129 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Tue, 27 Jul 2010 20:17:04 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 057CE45DE52 for ; Tue, 27 Jul 2010 20:17:04 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id D386045DE4D for ; Tue, 27 Jul 2010 20:17:03 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id B724CE08002 for ; Tue, 27 Jul 2010 20:17:03 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 5D3E71DB804D for ; Tue, 27 Jul 2010 20:17:03 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH 1/2] Add trace points to mmap, munmap, and brk In-Reply-To: <20100727110904.GA6519@mgebm.net> References: <20100721223359.8710.A69D9226@jp.fujitsu.com> <20100727110904.GA6519@mgebm.net> Message-Id: <20100727201644.2F46.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Tue, 27 Jul 2010 20:17:02 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Eric B Munson Cc: kosaki.motohiro@jp.fujitsu.com, akpm@linux-foundation.org, mingo@redhat.com, hugh.dickins@tiscali.co.uk, riel@redhat.com, peterz@infradead.org, anton@samba.org, hch@infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: > On Wed, 21 Jul 2010, KOSAKI Motohiro wrote: > > > > This patch adds trace points to mmap, munmap, and brk that will report > > > relevant addresses and sizes before each function exits successfully. > > > > > > Signed-off-by: Eric B Munson > > > > I don't think this is good idea. if you need syscall result, you should > > use syscall tracer. IOW, This tracepoint bring zero information. > > > > Please see perf_event_mmap() usage. Our kernel manage adress space by > > vm_area_struct. we need to trace it if we need to know what kernel does. > > > > Thanks. > > The syscall tracer does not give you the address and size of the mmaped areas > so this does provide information above simply tracing the enter/exit points > for each call. Why don't you fix this? > perf_event_mmap does provide the information for mmap calls. Originally I sent > a patch to add a trace point to munmap and Peter Z asked for corresponding points > in the mmap family. If the consensus is that the trace point in munmap is the > only one that should be added I can resend that patch. > > -- > Eric B Munson > IBM Linux Technology Center > ebmunson@us.ibm.com > -- 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/ . Don't email: email@kvack.org