From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30926 invoked by alias); 16 Dec 2011 18:37:30 -0000 Received: (qmail 30798 invoked by uid 22791); 16 Dec 2011 18:37:29 -0000 X-SWARE-Spam-Status: No, hits=-5.2 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 16 Dec 2011 18:37:09 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id pBGIb4Wr021110 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 16 Dec 2011 13:37:08 -0500 Received: from toonder.wildebeest.org (ovpn-116-18.ams2.redhat.com [10.36.116.18]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id pBGIWtpq029513 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 16 Dec 2011 13:32:56 -0500 Received: by toonder.wildebeest.org (Postfix, from userid 1000) id 1FD9320C9A; Fri, 16 Dec 2011 19:32:55 +0100 (CET) Date: Fri, 16 Dec 2011 19:01:00 -0000 From: Mark Wielaard To: David Smith Cc: systemtap@sourceware.org, Frank Eigler Subject: Re: [SCM] systemtap: system-wide probe/trace tool branch, master, updated. release-1.6-594-g12aa5f9 Message-ID: <20111216183254.GB2526@toonder.wildebeest.org> References: <20111213223224.10508.qmail@sourceware.org> <1323855764.3567.5.camel@springer.wildebeest.org> <4EE8C696.7000807@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4EE8C696.7000807@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2011-q4/txt/msg00378.txt.bz2 On Wed, Dec 14, 2011 at 09:53:58AM -0600, David Smith wrote: > On 12/14/2011 03:42 AM, Mark Wielaard wrote: > > > On Tue, 2011-12-13 at 22:32 +0000, fche@sourceware.org wrote: > > ... > > >> entry = (struct __stp_tf_vma_entry *) _stp_kmalloc_gfp(size, > >> - STP_ALLOC_SLEEP_FLAGS); > >> + STP_ALLOC_FLAGS); > > > > Urgh that hurts. Especially on memory constraint systems having to do > > non-sleeping allocations. Isn't there any way we can prevent this? Or at > > least detect that we are using a task_finder that doesn't notify us in > > user context? I think there are other places that assume the task_finder > > only notifies us about updates in user context, for example so we can > > check the build-id. Having a taks_finder that only operates in atomic > > contexts is pretty limiting. > > > We could postpone the pain a bit by changing the above to: > > #ifdef CONFIG_UTRACE > entry = (struct __stp_tf_vma_entry *) _stp_kmalloc_gfp(size, > STP_ALLOC_SLEEP_FLAGS); > #else > entry = (struct __stp_tf_vma_entry *) _stp_kmalloc_gfp(size, > STP_ALLOC_FLAGS); > #endif > > This way only systems using the new code use the non-sleepable alloc. That seems a nice compromise. I pushed that change. Commit efe1470. Thanks, Mark