On Sat, 24 May 2008, Robert Watson wrote: > Just as a reminder, we've just about reached the one month date before > IFF_NEEDSGIANT drivers are disabled in the build. You can find a > description of the general problem and list of specific drivers below. > > As USB work is on-going, I will *not* disable the USB drivers at this time, > but all other drivers in the list below will be disabled on 26 June. They > will remain in the tree, easily accessible for patch distribution and > re-enabling, until October, when any remaining non-MPSAFE drivers will be > deleted in 8.x. FreeBSD 8.0 will not ship with compatibility shims to > support non-MPSAFE network device drivers. An FYI on the state of things here: in the last month, John has updated a number of device drivers to be MPSAFE, and the USB work remains in-flight. I'm holding fire a bit on disabling IFF_NEEDSGIANT while things settle and I catch up on driver state, and will likely send out an update next week regarding which device drivers remain on the kill list, and generally what the status of this project is. Robert N M Watson Computer Laboratory University of Cambridge > > Robert N M Watson Computer Laboratory University of Cambridge > > ---------- Forwarded message ---------- > Date: Sun, 3 Feb 2008 20:59:05 +0000 (GMT) > From: Robert Watson <rwatson_at_FreeBSD.org> > To: arch_at_FreeBSD.org > Subject: 8.0 network stack MPsafety goals (fwd) > > > Only a few days after predicted, this is a reminder that IFF_NEEDSGIANT > network drivers are going to stop working in the forseeable future. Please > review the attached driver list, and if you depend on or care about a > Giant-dependent device driver, take action to make sure it doesn't remain on > the list in a month's time! > > (As far as I'm aware, the list has not changed since my December posting.) > > Robert N M Watson > Computer Laboratory > University of Cambridge > > ---------- Forwarded message ---------- > Date: Mon, 24 Dec 2007 10:43:28 +0000 (GMT) > From: Robert Watson <rwatson_at_FreeBSD.org> > To: arch_at_FreeBSD.org > Subject: 8.0 network stack MPsafety goals > > > Dear all: > > With the 7.0 release around the corner, many developers are starting to think > about (and in quite a few cases, work on) their goals for 8.0. One of our > on-going kernel projects has been the elimination of the Giant lock, and that > project has transformed into one of optimizating behavior on increasing > numbers of processors. > > In 7.0, despite the noteworth accomplishment of eliminating debug.mpsasfenet > and conditional network stack Gian acquisition, we were unable to fully > eliminate the IFF_NEEDSGIANT flag, which controls the conditional acquisition > of the Giant lock around non-MPSAFE network device drivers. Primarily these > drivers are aging ISA network device drivers, although there are some > exceptions, such as the USB stack. > > This e-mail proposes the elimination of the IFF_NEEDSGIANT flag and > associated infrastructure in FreeBSD 8.0, meaning that all network device > drivers must be able to operate without the Giant lock (largely the case > already). Remaining drivers using the IFF_NEEDSGIANT flag must either be > updated, or less ideally, removed. I propose the following schedule: > > Date Goals > ---- ----- > 26 Dec 2007 Post proposed schedule for flag and infrastructure removal > Post affected driver list > > 26 Jan 2008 Repost proposed schedule for flag and infrastructure removal > Post updated affected driver list > > 26 Feb 2008 Adjust boot-time printf for affect drivers to generate a loud > warning. > Post updated affected driver list > > 26 May 2008 Post HEADS UP of impending driver disabling > Post updated affected driver list > > 26 Jun 2008 Disable build of all drivers requiring IFF_NEEDSGIANT > Post updated affected driver list > > 26 Sep 2008 Post HEADS up of impending driver removal > Post updated affected driver list > > 26 Oct 2008 Delete source of all drivers requiring IFF_NEEDSGIANT > Remove flag and infrastructure > > Here is a list of potentially affected drivers: > > Name Bus Man page description > --- --- -------------------- > ar ISA/PCI synchronous Digi/Arnet device driver > arl ISA Aironet Arlan 655 wireless network adapter driver > awi PCCARD AMD PCnetMobile IEEE 802.11 PCMCIA wireless network > driver > axe USB ASIX Electronics AX88172 USB Ethernet driver > cdce USB USB Communication Device Class Ethernet driver > cnw PCCARD Netwave AirSurfer wireless network driver > cs ISA/PCCARD Ethernet device driver > cue USB CATC USB-EL1210A USB Ethernet driver > ex ISA/PCCARD Ethernet device driver for the Intel EtherExpress > Pro/10 and Pro/10+ > fe CBUS/ISA/PCCARD Fujitsu MB86960A/MB86965A based Ethernet adapters > ic I2C I2C bus system > ie ISA Ethernet device driver > kue USB Kawasaki LSI KL5KUSB101B USB Ethernet driver > oltr ISA/PCI Olicom Token Ring device driver > plip PPBUS printer port Internet Protocol driver > ppp TTY point to point protocol network interface > ray PCCARD Raytheon Raylink/Webgear Aviator PCCard driver > rue USB RealTek RTL8150 USB to Fast Ethernet controller > driver > rum USB Ralink Technology USB IEEE 802.11a/b/g wireless > network device > sbni ISA/PCI Granch SBNI12 leased line modem driver > sbsh PCI Granch SBNI16 SHDSL modem device driver > sl TTY slip network interface > snc ISA/PCCARD National Semiconductor DP8393X SONIC Ethernet adapter > driver > sr ISA/PCI synchronous RISCom/N2 / WANic 400/405 device driver > udav USB Davicom DM9601 USB Ethernet driver > ural USB Ralink Technology RT2500USB IEEE 802.11 driver > xe PCCARD Xircom PCMCIA Ethernet device driver > zyd USB ZyDAS ZD1211/ZD1211B USB IEEE 802.11b/g wireless > network device > > In some cases, the requirement for Giant is a property of a subsystem the > driver depends on as the driver itself; for example, the tty subsystem for > SLIP and PPP, and the USB subsystem for a number of USB ethernet and wireless > drivers. With most of a year before to go on the proposed schedule, my hope > is that we will have lots of time to address these issues, but wanted to get > a roadmap out from a network protocol stack architecture perspective so that > device driver and subsystem authors could have a schedule in mind. > > FYI, the following drivers also reference IFF_NEEDSGIANT, but only in order > to provide their own conditional MPSAFEty, which can be removed without > affecting device driver functionality (I believe): > > Name Bus Man page description > --- --- -------------------- > ce PCI driver for synchronous Cronyx Tau-PCI/32 WAN adapters > cp PCI driver for synchronous Cronyx Tau-PCI WAN adapters > ctau ISA driver for synchronous Cronyx Tau WAN adapters > cx ISA driver for synchronous/asynchronous Cronyx Sigma WAN > adapters > > Developers and users of the above drivers are heavily encouraged to update > the drivers to remove dependence on Giant, and/or make other contingency > plans. > > Robert N M Watson > Computer Laboratory > University of Cambridge > _______________________________________________ > freebsd-arch_at_freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-arch > To unsubscribe, send any mail to "freebsd-arch-unsubscribe_at_freebsd.org" > _______________________________________________ > freebsd-arch_at_freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-arch > To unsubscribe, send any mail to "freebsd-arch-unsubscribe_at_freebsd.org" > _______________________________________________ > freebsd-arch_at_freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-arch > To unsubscribe, send any mail to "freebsd-arch-unsubscribe_at_freebsd.org" >Received on Sun Jun 29 2008 - 15:02:50 UTC
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