cvs commit: src/sys/dev/bce if_bce.c src/sys/dev/em if_em.c if_em.h src/sys/dev/mpt mpt.h mpt_pci.c

Thu Nov 16 05:05:44 UTC 2006

In message: <455BA914.7010602 at samsco.org>
            Scott Long <scottl at samsco.org> writes:
: M. Warner Losh wrote:
: > In message: <455BA0B6.1000109 at samsco.org>
: >             Scott Long <scottl at samsco.org> writes:
: > : M. Warner Losh wrote:
: > : > In message: <200611151756.31047.jhb at freebsd.org>
: > : >             John Baldwin <jhb at freebsd.org> writes:
: > : > : On Wednesday 15 November 2006 17:51, M. Warner Losh wrote:
: > : > : > In message: <455B963A.4050200 at samsco.org>
: > : > : >             Scott Long <scottl at samsco.org> writes:
: > : > : > : John Baldwin wrote:
: > : > : > : > On Wednesday 15 November 2006 16:51, Ruslan Ermilov wrote:
: > : > : > : >> On Thu, Nov 16, 2006 at 12:51:19AM +0300, Ruslan Ermilov wrote:
: > : > : > : >>> On Wed, Nov 15, 2006 at 08:04:57PM +0000, John Baldwin wrote:
: > : > : > : >>>> jhb         2006-11-15 20:04:57 UTC
: > : > : > : >>>>
: > : > : > : >>>>   FreeBSD src repository
: > : > : > : >>>>
: > : > : > : >>>>   Modified files:
: > : > : > : >>>>     sys/dev/bce          if_bce.c 
: > : > : > : >>>>     sys/dev/em           if_em.c if_em.h 
: > : > : > : >>>>     sys/dev/mpt          mpt.h mpt_pci.c 
: > : > : > : >>>>   Log:
: > : > : > : >>>>   Add MSI support to em(4), bce(4), and mpt(4).  For now, we only 
: > : > : > : > support
: > : > : > : >>>>   devices that support a maximum of 1 message, and we use that 1 
: > : > : message
: > : > : > : >>>>   instead of the INTx rid 0 IRQ with the same interrupt handler, etc.
: > : > : > : >>>>   
: > : > : > : >>>>   Revision  Changes    Path
: > : > : > : >>>>   1.19      +11 -3     src/sys/dev/bce/if_bce.c
: > : > : > : >>>>   1.164     +11 -2     src/sys/dev/em/if_em.c
: > : > : > : >>>>   1.56      +1 -0      src/sys/dev/em/if_em.h
: > : > : > : >>>>   1.31      +1 -0      src/sys/dev/mpt/mpt.h
: > : > : > : >>>>   1.39      +14 -1     src/sys/dev/mpt/mpt_pci.c
: > : > : > : >>>>
: > : > : > : >>> How will the "vmstat -i" output look like for MSI-enabled devices?
: > : > : > : >>>
: > : > : > : >> irqXXXX, where XXXX>=1024?
: > : > : > : > 
: > : > : > : > s/1024/256/
: > : > : > : > 
: > : > : > : 
: > : > : > : There is a problem here, though.  Newbus prints out the IRQ number after
: > : > : > : a successful device probe phase.  It has no knowledge of MSI at that 
: > : > : > : point, so it just prints out the traditional IRQ value.  At some point,
: > : > : > : this needs to be fixed.  Having the driver tell newbus about its MSI
: > : > : > : intentions in the probe routine is unrealistic, so there is no quick
: > : > : > : fix there.  Probably need to delay printing the device message until
: > : > : > : later in the attach routine, once the driver has set up all of the 
: > : > : > : resources.
: > : > : > 
: > : > : > I've been wanting to move the printing of the attach string from
: > : > : > post-probe, pre-attach to post-attach for some time now.  We would
: > : > : > then report the resources assigned to the device.  I'm not sure if I'd
: > : > : > print all the resources assigned, or only those the driver activates.
: > : > : > Both sides of the argument have merit, imho.  On the pro side,
: > : > : > resources are used, and printing them will help highlight conflicts.
: > : > : > On the con side, people think it clutters things up too much and might
: > : > : > lead to false expectations.
: > : > : > 
: > : > : > When I've mentioned this desire at various developer summits, I was
: > : > : > told basically "go for it, but only at freebsd X.0 since people have
: > : > : > dmesg parsers" by many people (maybe even including Scott).
: > : > : 
: > : > : Also, the way it works now, if attach fails and the routine prints out error 
: > : > : messages, you get to see line for the device first with the initial resources 
: > : > : and then you see the error message from the driver.  If you move the printf 
: > : > : down, then all you get is an error message from the driver.  At the very 
: > : > : least this would break POLA for a lot of our users.  I'm still undecided.
: > : > : I could add a printf when a device ends up succesfully allocating MSI or MSI-X 
: > : > : IRQs if people desired.
: > : > 
: > : > I'd prefer those be under bootverbose.
: > : > 
: > : > I think the real answer may be to get devinfo output to be real...
: > : > 
: > : > Warner
: > : 
: > : Yeah, the resource info really is superfluous during boot.  It looks 
: > : cool in the old-school unix way, but that's about it.  Maybe it's time
: > : to change newbus to only print the driver name and driver-supplied 
: > : description after the probe phase, like you hint at.  newbus could then
: > : print resource info as the driver activates it, if bootverbose is set.
: > : I'd support something like this for 7.0, even if devinfo doesn't get
: > : fully fixed.  If MSI gets merged to RELENG_6, then we'll just have to
: > : live with the incorrect newbus prints.
: > : 
: > : So for example, I would change this:
: > : 
: > : atapci0: <Intel ICH5 SATA150 controller> port 
: > : 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0xfc00-0xfc0f at device 31.2 on pci0
: > : 
: > : into:
: > : 
: > : atapci0: <Intel ICH5 SATA150 controller> at device 31.2 on pci0
: > 
: > That's exactly what I'm thinking too.  Glad to see we're on the same
: > page.
: > 
: > : Calls to bus_activate_resouce/bus_alloc_resource(RF_ACTIVE) could then
: > : print the various resources, contingent on bootverbose being set.  This
: > : would make the ugly [GIANT_LOCKED] and [FAST] messages that get printed
: > : right now have a chance of being more consistent.
: > 
: > I was thinking that if we printed things last, we could potentially
: > eliminate them from normal use and just print them as part of the
: > resources (optionally?):
: > 
: > atapci0: port 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0xfc00-0xfc0f irq 23 [FAST]
: > 
: > or something similar...
: > 
: > Warner
: 
: Sounds good.  Beware that MSI makes it possible to have as many as 64
: interrupts per device, though it's more common to have anywhere from 1
: to 8.  I'd probably split up your above line into 2 lines, one for
: memory resources and one for interrupt resources.

Is there some convention for MSI naming?  Or are the resources
basically anonymous?

Warner