On vnode backed md(4) devices over a certain, currently undetermined
size relative to the buffer cache our "lemming-syncer" can provoke
a buffer starvation which puts the md thread to sleep on wdrain.
This generally tends to grind the entire system to a stop because the
event that is supposed to wake up the thread will not happen until a fair
bit of the piled up I/O requests in the system finish, and since a lot
of those are on a md(4) vnode backed device which is currently waiting
on wdrain until a fair amount of the piled up ... you get the picture.
The cure is to issue all VOP_WRITES on the vnode backing the device
with IO_SYNC.
In addition to more closely emulating a real disk device with a
non-lying write-cache, this makes the writes exempt from rate-limited
(there to avoid starving the buffer cache) and consequently prevents
the deadlock.
Unfortunately performance takes a hit.
Add "async" option to give people who know what they are doing the
old behaviour.
This may not be a generally valid configuration, but neither is relying
on the PCI clock to be stable.
The only currently known and supported hardware is the VPN14x1 from
Soekris, and since it has external clock, we fail safe(r) by using
it.
Unfortunately there is no way to probe this reliably.
ndis_probe_pci() doesn't contain an entry for an IRQ resource, try to
force one to be routed to us anyway by adding an extra call to
bus_alloc_resource(). If this fails, then we have to abort the attach.
Patch provided by jhb, tweaked by me.
prevented newfs to work on volumes that are larger than 1TB.
PR: 63577
Submitted by: Masaki Takakashi <mtakahashi@se.gtd.cosmo.co.jp>
Approved by: grog (mentor), bde
if_ndis.c has been split into if_ndis_pci.c and if_ndis_pccard.c.
The ndiscvt(8) utility should be able to parse device info for PCMCIA
devices now. The ndis_alloc_amem() has moved from kern_ndis.c to
if_ndis_pccard.c so that kern_ndis.c no longer depends on pccard.
NOTE: this stuff is not guaranteed to work 100% correctly yet. So
far I have been able to load/init my PCMCIA Cisco Aironet 340 card,
but it crashes in the interrupt handler. The existing support for
PCI/cardbus devices should still work as before.
The previous logic meant that if a user sets it to a minimal cooling value
acpi_thermal will not use higher cooling levels. Reverse the logic so that
the user requesting a level (say, 2) also gets 0 - 1 also.
PR: kern/61592
Submitted by: Andrew Thompson <andy@fud.org.nz>
even though the spec mandates this. Some have a value of 5 to indicate
throttling + C2 and some have 7 to indicate an extra C3 state. Support
throttling if the value is >= 4, C2 for >= 5, and C3 for >= 6.
Sort acpi debug values. Change "disable" to "disabled" to match rest of
the kernel. Remove debugging from acpi_toshiba since it was only used for
probe/attach.
checking and freeing a different pointer that may or may not have been
assigned the same value. This should fix panics under load that were
recently reported.
