From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [GIT PULL] please pull ummunotify Date: Thu, 17 Sep 2009 13:30:28 +0200 Message-ID: <1253187028.8439.2.camel@twins> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Roland Dreier Cc: torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, jsquyres-FYB4Gu1CFyUAvxtiuMwx3w@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, general-ZwoEplunGu1OwGhvXhtEPSCwEArCW2h5@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Anton Blanchard , Paul Mackerras , Ingo Molnar List-Id: linux-rdma@vger.kernel.org On Thu, 2009-09-10 at 21:38 -0700, Roland Dreier wrote: > Linus, please consider pulling from >=20 > master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband.git= ummunotify >=20 > This tree is also available from kernel.org mirrors at: >=20 > git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband.g= it ummunotify >=20 > This will get "ummunotify," a new character device that allows a > userspace library to register for MMU notifications; this is > particularly useful for MPI implementions (message passing libraries > used in HPC) to be able to keep track of what wacky things consumers > do to their memory mappings. My colleague Jeff Squyres from the Open > MPI project posted a blog entry about why MPI wants this: >=20 > http://blogs.cisco.com/ciscotalk/performance/comments/better_linux_me= mory_tracking/ >=20 > His summary of ummunotify: >=20 > "It=E2=80=99s elegant, doesn=E2=80=99t require strange linker trick= s, and seems to > work in all cases. Yay!" >=20 > This code went through several review iterations on lkml and was in > -mm and -next for quite a few weeks. Andrew is OK with merging it (I > think -- Andrew please correct me if I misunderstood you). Anton Blanchard suggested a while back that this might be integrated with perf-counters, since perf-counters already does mmap() tracking an= d also provides events through an mmap()'ed buffer. Has anybody looked into this? If someone did and I missed the discussion on why it isn't appropriate, kindly point me in the right direction ;-) -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html