Releasing items from the mt_zone can not be done by a simple
uma_zfree() call since mt_zone is allocated with the UMA_ZONE_MALLOC
flag. Use uma_zfree_arg instead and supply the slab.
This bug caused panics in low memory situations on unloading kernel
modules containing MALLOC_DEFINE(..) statements.
Submitted by: ups
into a separate module. Accordingly, convert the option into a device
named similarly.
Note for MFC: Perhaps the option should stay in RELENG_6 for POLA reasons.
Suggested by: scottl
Reviewed by: cokane
MFC after: 5 days
re-organizing the monitor return logic. We perform interface monitoring
checks after we have determined if the CRC is still on the packet, if
it is, m_adj() is called which will adjust the packet length. This
ensures that we are not including CRC lengths in the byte counters for
each packet.
Discussed with: andre, glebius
that we might have address collisions, so make sure that this hardware address
isn't already in use on another bridge.
Submitted by: csjp
MFC after: 1 month
destination interface as a member of our bridge or this is a unicast packet,
push it through the bpf(4) machinery.
For broadcast or multicast packets, don't bother with the bpf(4) because it will
be re-injected into ether_input. We do this before we pass the packets through
the pfil(9) framework, as it is possible that pfil(9) will drop the packet or
possibly modify it, making it very difficult to debug firewall issues on the
bridge.
Further, implemented IFF_MONITOR for bridge interfaces. This does much the same
thing that it does for regular network interfaces: it pushes the packet to any
bpf(4) peers and then returns. This bypasses all of the bridge machinery,
saving mutex acquisitions, list traversals, and other operations performed by
the bridging code.
This change to the bridging code is useful in situations where individuals use a
bridge to multiplex RX/TX signals from two interfaces, as is required by some
network taps for de-multiplexing links and transmitting the RX/TX signals
out through two separate interfaces. This behaviour is quite common for network
taps monitoring links, especially for certain manufacturers.
Reviewed by: thompsa
MFC after: 1 month
Sponsored by: Seccuris Labs
be called without any vnode locks held. Remove calls to vn_start_write() and
vn_finished_write() in vnode_pager_putpages() and add these calls before the
vnode lock is obtained to most of the callers that don't already have them.
has many positive effects including improved smp locking, reducing
interdependencies between mounts that can lead to deadlocks, etc.
- Add the softdep worklist and various counters to the ufsmnt structure.
- Add a mount pointer to the workitem and remove mount pointers from the
various structures derived from the workitem as they are now redundant.
- Remove the poor-man's semaphore protecting softdep_process_worklist and
softdep_flushworklist. Several threads may now process the list
simultaneously.
- Add softdep_waitidle() to block the thread until all pending
dependencies being operated on by other threads have been flushed.
- Use softdep_waitidle() in unmount and snapshots to block either
operation until the fs is stable.
- Remove softdep worklist processing from the syncer and move it into the
softdep_flush() thread. This thread processes all softdep mounts
once each second and when it is called via the new softdep_speedup()
when there is a resource shortage. This removes the softdep hook
from the kernel and various hacks in header files to support it.
Reviewed by/Discussed with: tegge, truckman, mckusick
Tested by: kris
speeds to perform below the desired bitrate and throughput will be erratic.
This makes queueing work on the Geode SC1100, K5 model 0 and IDT WinChip C6
processors.
MFC after: 3 days
with malloc() or contigmalloc() as usual, but try to re-map the allocated
memory into a VA outside the KVA, non-cached, thus making the calls to
bus_dmamap_sync() for these buffers useless.
to call back for completition and something else is holding the taskqueue
waiting for ATA to return data.
This should clear up the "semaphore timeout !! DANGER Will Robinson !!"
in most situations, and log "taskqueue timeout - completing request directly"
instead, with a delayed "WARNING - freeing taskqueue zombie request" when
the taskqueue finally calls us back with the now stale request.
(It would have been nice if there was a way to remove a scheduled item from
a taskqueue, but that is not currently implemented in the kernel).
A real fix for this is in the works but wont make it to 6.1RELEASE
definite MFC candidate.
- Don't use a common buffer in the softc to store per-command data. Reserve
a buffer in the command itself.
- Don't allocate DMA memory for the kernel command structures when all you
really need is DMA memory for the scratch buffer embedded in them. Instead
allocate a slab for the scratch buffers and divide it up as needed.
- Call bus_dmamap_unload() at the completion of commands.
- Preserve and clear the CAM CCB status flags at completion.
- Reorder some low-level command operations to try to close races.
- Limit the simq to 32 commands for now. There are some serious problems
with the driver under load that are not well understood, so keeping the
simq lower helps avoid this. It has been tested at a higher value, but
this is a safe value that doesn't show much performance degredation.
These changes allow the driver to work reliably with >4GB of memory on i386
and amd64, and also work around deadlocks seen under very high load in
certain situations. The work-around is far from ideal, but without and
documentation it is hard to know what the right fix is.
MFC candidate
By default syscons(4) will look for the kbdmux(4) keyboard first, and then,
if not found, look for any keyboard.
Current kbd code is modified so if kbdmux(4) is the current keyboard, all
new keyboards are automatically added to the kbdmux(4).
Switch to kbdmux(4) can be done at boot time, by loading kbdmux module at
the loader prompt, or at runtime, by kldload'ing the kbdmux module and
releasing current active keyboard.
If, for whatever reason, kbdmux(4) is not required/desired then just do
not load it and everything should work as before. It is also possible to
kldunload kbdmux at runtime and syscons(4) will automatically switch to
the first available keyboard.
No response from: freebsd-current@
MFC after: 1 day
right from the beginning and partly clean up the differences in handling
between SYN_SENT and SYN_RCVD (syncache).
Further changes to this code to come. This is a first incremental step
to a general overhaul and streamlining of the TCP code.
PR: kern/15095
PR: kern/92690 (partly)
Reviewed by: qingli (and tested with ANVL)
Sponsored by: TCP/IP Optimization Fundraise 2005
- Throw out all of the logical APIC ID stuff. The Intel docs are somewhat
ambiguous, but it seems that the "flat" cluster model we are currently
using is only supported on Pentium and P6 family CPUs. The other
"hierarchy" cluster model that is supported on all Intel CPUs with
local APICs is severely underdocumented. For example, it's not clear
if the OS needs to glean the topology of the APIC hierarchy from
somewhere (neither ACPI nor MP Table include it) and setup the logical
clusters based on the physical hierarchy or not. Not only that, but on
certain Intel chipsets, even though there were 4 CPUs in a logical
cluster, all the interrupts were only sent to one CPU anyway.
- We now bind interrupts to individual CPUs using physical addressing via
the local APIC IDs. This code has also moved out of the ioapic PIC
driver and into the common interrupt source code so that it can be
shared with MSI interrupt sources since MSI is addressed to APICs the
same way that I/O APIC pins are.
- Interrupt source classes grow a new method pic_assign_cpu() to bind an
interrupt source to a specific local APIC ID.
- The SMP code now tells the interrupt code which CPUs are avaiable to
handle interrupts in a simpler and more intuitive manner. For one thing,
it means we could now choose to not route interrupts to HT cores if we
wanted to (this code is currently in place in fact, but under an #if 0
for now).
- For now we simply do static round-robin of IRQs to CPUs when the first
interrupt handler just as before, with the change that IRQs are now
bound to individual CPUs rather than groups of up to 4 CPUs.
- Because the IRQ to CPU mapping has now been moved up a layer, it would
be easier to manage this mapping from higher levels. For example, we
could allow drivers to specify a CPU affinity map for their interrupts,
or we could allow a userland tool to bind IRQs to specific CPUs.
The MFC is tentative, but I want to see if this fixes problems some folks
had with UP APIC kernels on 6.0 on SMP machines (an SMP kernel would work
fine, but a UP APIC kernel (such as GENERIC in RELENG_6) would lose
interrupts).
MFC after: 1 week
to allow PHOLD()'s of processes that have P_WEXIT set as once that flag
is set we aren't guaranteed to block in exit1() waiting for the PRELE()
(we might already be past the wait). However, curproc is a bit of a
special case. By the time P_WEXIT is set, the process is single-threaded,
so the only thread for which can do a PHOLD(curproc) is the thread
executing in exit1(). The fact that this thread is executing ensures
that the process won't go away before the current hold is released via
PRELE(). This fixes some panics due to kicking off softupdate operations
inside of exit1() after the recent PHOLD changes to fix ptrace/procfs vs
exit races.
MFC after: 1 week
Tested by: pho
mpt_soft_reset more than once. And to wait for MPT_DB_STATE_READY
twice. I mean, this is crucial- give the IOC a chance to get
ready.
If mpt_reset is called to reinit things, and we succeed, make
sure to re-enable interrupts. This is what has mostly led to
system lockup after having to hard reset the chip. Also, if
we think that interrupts aren't function in mpt_cam_timeout,
for goodness sake, turn them on again.
In read_cfg_header, return distinguishing errnos so the caller
can decide what's an error. It's *not* an error to fail to
read a RAID page from a non-RAID capable device like the FC929X.
Some whitespace fixes (removing spaces from ends of lines).
Developed with: Norbert Koch < NKoch at demig dot de >
No response from: freebsd-current@
Tested by: Norbert Koch < NKoch at demig dot de >
MFC after: 1 day
- use the cu_bridge_id rather than the cu_rootid for the bridge address [1]
- the memcmp return value is not signed so the wrong interface may have been
selected
- fix up the calculation of sc_bridge_id
PR: kern/93909 [1]
MFC after: 3 days
and want to have crypto support loaded as KLD. By moving zlib to separate
module and adding MODULE_DEPEND directives, it is possible to use such
configuration without complication. Otherwise, since IPSEC is linked with
zlib (just like crypto.ko) you'll get following error:
interface zlib.1 already present in the KLD 'kernel'!
Approved by: cognet (mentor)
Otherwise a kernel build would break in the coda5 module if the main
kernel conf file enabled CODA_COMPAT_5, too. Redefined symbols are
strictly disallowed by -Werror.
To overcome this issue, introduce a different symbol indicating coda5
build, CODA5_MODULE, and translate it to CODA_COMPAT_5 appropriately
in /sys/coda/coda.h.
MFC after: 3 days
so other threads can not see it if we unlock the proc
lock (this can happen in knlist_delete). Don't do wakeup,
it is not necessary.
2. Decrease kaio_buffer_count in biohelper rather than
doing it in aio_bio_done_notify.
3. In aio_bio_done_notify, don't send notification if KAIO_RUNDOWN
was set, because the process is already in single thread mode.
4. Use assignment to initialize aiothreadflags.
5. AIOCBLIST_RUNDOWN is not useful, axe the code using it.
6. use LIO_NOP instead of zero.
not hang the system for 5 seconds. If a TMF doesn't complete within,
oh, say 500ms, that's enough.
Put in a printout to catch mpt_recover_commands being activated with
no commands.
*both* SAS and FC, not just SAS.
b) Don't tell the chip we want it to do FIFO signalling if we actually
don't set up the address where the FIFO signal is supposed to be written
(oops).
is closed and then reopened. This appears to be necessary now that
we no longer clear endpoint stalls every time a pipe is opened.
Previously we could assume an initial toggle value of zero because
the clear-stall operation resets the device's toggle state.
Reported by: Holger Kipp
MFC after: 3 days
(atkbd(4)) and PS/2 mouse (psm(4)) are used together.
Turns out that atkbd(4) check_char() method may return "true" while
read_char() method returns NOKEY. When this happens kbdmux(4) was
simply stuck in the dead loop. Avoid dead loop in kbdmux(4) by breaking
out of the loop if read_char() method returns NOKEY.
It almost seems like a bug in atkkbd(4), atkbd_check_char() calls
kbdc_data_ready(), and, the later will return "true" if there are
pending data in either kbd or aux queue. However, because both aux
and kbd are on the same controller, I'm not sure if this is a bug
or feature.
Tested by: markus
MFC after: 1 day
is finished with it; this may only occur when the tx queue is setup as
dba-gated but since the fix is cheap apply it to all queues
while here make the queue depth signed for use in assertions
Reviewed by: apatti
MFC after: 2 weeks
inside !if defined(KERNBUILDDIR).
Utilize the fact the module will support all frames by default --
it needs no ETHER_* options unless some frames need to be disabled.
Fix the comment respectively.
Don't forget to create fake opt_ef.h if no ETHER_* are set.
MFC after: 3 days
o Add defines for the 5 interrupt sources typical for serial devices.
These defines can be used for more finegrained interrupt handling
between drivers that cooperatively handle multiple serial ports.
o Add defines for the various bitmasks applicable when all information
is passed between drivers as a single integral.
Return BUS_PROBE_LOW_PRIORITY for a successful probe. This is in
preparation of the introduction of scc(4), which is going to handle
SCCs in the near future.
simultaneous open. Both the bug and the patch were verified using the
ANVL test suite.
PR: kern/74935
Submitted by: qingli (before I became committer)
Reviewed by: andre
MFC after: 5 days
callout_drain() logic. We no longer need a separate non-spin mutex to
do sleep/wakeup with, instead we can now just use the one spin mutex to
manage all the callout functionality.
mutex.
- Don't use callout_drain() to stop the toffhandle callout while holding the
fdc mutex (this could deadlock) in functions called from softclock
(callouts aren't allowed to do voluntary sleeps). Instead, use
callout_stop(). Note that since we hold the associated mutex and are now
using callout_init_mtx(), callout_stop() is just as effective as
callout_drain(). (Though callout_drain() is still needed in detach to
make sure softclock isn't contesting on our mutex before we destroy the
mutex.)
- Remove unused callout 'tohandle' from softc.
MFC after: 1 week
the last reference is dropped. I forgot that vnodes can stick around
for a very long time until processes discover that they are dead. This
means that a vnode reference is not sufficient to keep the mount
referenced and even more code will be required to ref mount points.
Discovered by: kris
- Reorder the events in exit(2) slightly so that we trigger the S_EXIT
stop event earlier. After we have signalled that, we set P_WEXIT and
then wait for any processes with a hold on the vmspace via PHOLD to
release it. PHOLD now KASSERT()'s that P_WEXIT is clear when it is
invoked, and PRELE now does a wakeup if P_WEXIT is set and p_lock drops
to zero.
- Change proc_rwmem() to require that the processing read from has its
vmspace held via PHOLD by the caller and get rid of all the junk to
screw around with the vmspace reference count as we no longer need it.
- In ptrace() and pseudofs(), treat a process with P_WEXIT set as if it
doesn't exist.
- Only do one PHOLD in kern_ptrace() now, and do it earlier so it covers
FIX_SSTEP() (since on alpha at least this can end up calling proc_rwmem()
to clear an earlier single-step simualted via a breakpoint). We only
do one to avoid races. Also, by making the EINVAL error for unknown
requests be part of the default: case in the switch, the various
switch cases can now just break out to return which removes a _lot_ of
duplicated PRELE and proc unlocks, etc. Also, it fixes at least one bug
where a LWP ptrace command could return EINVAL with the proc lock still
held.
- Changed the locking for ptrace_single_step(), ptrace_set_pc(), and
ptrace_clear_single_step() to always be called with the proc lock
held (it was a mixed bag previously). Alpha and arm have to drop
the lock while the mess around with breakpoints, but other archs
avoid extra lock release/acquires in ptrace(). I did have to fix a
couple of other consumers in kern_kse and a few other places to
hold the proc lock and PHOLD.
Tested by: ps (1 mostly, but some bits of 2-4 as well)
MFC after: 1 week
interrupt handlers rather than BUS_SETUP_INTR() and BUS_TEARDOWN_INTR().
Uses of the BUS_*() versions in the implementation of foo_intr methods
in bus drivers were not changed. Mostly this just means that some
drivers might start printing diagnostic messages like [FAST] when
appropriate as well as honoring mpsafenet=0.
- Fix two more of the ppbus drivers' identify routines to function
correctly in the mythical case of a machine with more than one ppbus.
associated with the passed in pfs_node. If it does return a pointer, it
keeps the process locked. This allows a lot of places that were calling
pfind() again right after pfs_visible() to not have to do that and avoids
races since we don't drop the proc lock just to turn around and lock it
again. This will become more important with future changes to fix races
between procfs/ptrace and exit(2). Also, removed a duplicate pfs_visible()
call in pfs_getextattr().
Reviewed by: des
MFC after: 1 week
modules prior to looking up the directory which we will cover to avoid
this problem in mount.
- We must hold the coveredvp locked before we can busy the mountpoint to
prevent a lock order reversal with the vfs_busy() in lookup which holds
the directory lock prior to doing a vfs_busy(). The directory lock is
required to safely clear the v_mountedhere field on the directory.
MFC After: 1 week
prevent the mount point from going away while we're waiting on the lock.
The ref does not need to persist once we have the lock because the
lock prevents the mount point from being unmounted.
MFC After: 1 week
the VFS_STATFS call to prevent the mount from disappearing while we're
stating.
- Convert these routines to use MPSAFE namei semantics.
MFC After: 1 week
vop_lock_post do not trigger.
- Rearrange null_inactive to null_hashrem earlier so there is no chance
of finding the null node on the hash list after the locks have been
switched.
- We should never have a NULL lowervp in null_reclaim() so there is
no need to handle this situation. panic instead.
MFC After: 1 week
- Simplify the logic dealing with recycled vnodes in null_hashget() and
null_hashins(). Since we hold the lower node locked in both cases
the null node can not be undergoing recycling unless reclaim somehow
called null_nodeget(). The logic that was in place was not safe and
was essentially dead code.
MFC After: 1 week
object that requires Giant in vm_object_deallocate(). This is somewhat
hairy in that if we can't obtain Giant directly, we have to drop the
object lock, then lock Giant, then relock the object lock and verify that
we still need Giant. If we don't (because the object changed to OBJT_DEAD
for example), then we drop Giant before continuing.
Reviewed by: alc
Tested by: kris
a calcru() wrapper that passes a local rusage_ext on the stack that is
a snapshot to do the calculations on. Now we can pass p->p_crux to
calcru1() in calccru() again which fixes the issues with runtime going
backwards messages when dead processes are harvested by init.
Reviewed by: phk
Tested by: Stefan Ehmann shoesoft at gmx dot net
processing the interrupt events. If we clear them afterwards we
can completely miss some events as the NIC can change the source
flags while we're in the handler. In order to not get another
interrupt while we're in ifp->if_input() with the driver lock
dropped we now turn off NIC interrupts while in the interrupt
handler. Previously this was meant to be achieved by clearing the
interrupt source flags after processing the interrupt events but
didn't really work as clearing these flags doesn't actually
acknowledge and re-enable the events.
This fixes the device timeouts seen with the VMware LANCE.
- Relax the watchdog timer somewhat; don't enable it until the last
packet is enqueued and if there is a TX interrupt but there are
still outstanding ones reload the timer.
Reported and tested by: Morten Rodal <morten@rodal.no>
MFC after: 3 days
if ksocket is connected to an interface-type node somewhere later
in the graph (e.g., ng_eiface or ng_iface), the csum_data may be
applied to a wrong packet (if we encapsulate Ethernet or IP).
MFC after: 3 days
The ed driver on pc98 was broken by if_edvar.h rev1.31.
Reported by: Kaho Toshikazu (kaho at elam kais kyoto-u ac jp)
Tested by: Eiji Kato (ekato at a1 mbn or jp)
MFC after: 3 days
More info regarding these nics can be found at http://www.myri.com.
Please note that the files
sys/dev/myri10ge/{mcp_gen_header.h,myri10ge_mcp.h} are internally
shared between all our drivers (solaris, macosx, windows, linux, etc).
I'd like to keep these files unchanged, so I can just import newer
versions of them when the firmware API/ABI changes. This means I'm
stuck with some of the crazy-long #define names, and possibly
non-style(9) characteristics of these files.
Many thanks to mlaier for doing firmware(9) just as I
needed it, and to scottl for his helpful review.
Reviewed by: scottl, glebius
Sponsored by: Myricom Inc.
when option DEBUG_LOCKS is used. Trap frames are determined by checking
whether the caller was one of the tl0_*() or tl1_*() asm functions via
a newly added pair of dummy symbols in exception.S which mark the begin
and end of these functions. The tl_trap_* pair marks those in the special
.trap section and the tl_text_* in the regular .text section. Because
of their performance penalty db_search_symbol()/db_symbol_values() and
linker_ddb_search_symbol()/linker_ddb_symbol_values() aren't used here
for determining the caller, with db_search_symbol()/db_symbol_values()
additionally not being reentrant.
- For consistency, change db_backtrace() to also use the new markers for
determining the tl0_*() and tl1_*() asm functions instead of bcmp()'ing
the symbol name.
- Use FBSDID in db_trace.c.
PR: 93226
Based on a patch by: Antoine Brodin <antoine.brodin@laposte.net>
Ok'ed by: jhb
Without CODA_COMPAT_5, it would be equivalent to the plain coda
module. Therefore just add -DCODA_COMPAT_5 to CFLAGS instead of
fiddling with opt_coda.h. This is particularly important when
the module is built along with the kernel and CODA_COMPAT_5 isn't
in the kernel conf file (and so not in opt_coda.h either).
MFC after: 3 days
nfs_diskless.c if NFS_ROOT is in effect, e.g., present
in the kernel config file. Otherwise the built module
won't load due to an undefined reference to nfs_setup_diskless.
MFC after: 3 days
can't be changed from userland. Make them read-only and provide
descriptions.
kern.ipc.max_datalen must never be less than one byte. Enforce this
with a panic in net_init_domain().
Sponsored by: TCP/IP Optimization Fundraise 2005
MFC after: 3 days
forcing DMA alignment to default buffer size.
- Make sure DMA pointer properly aligned to avoid being truncated by caller
which causing severe underruns and random popping (especially in 32bit
playback / recording).
- Add AC97 inverted external amplifier quirk for Maxselect x710s
- http://maxselect.ru/
MFC after: 1 week
current directory to allow user rules to create the firmware (e.g. from a
uuencoded blob). make's version of if is evaluated too early to catch this.
Found-by: gallatin
the SMI/TCO address space. Switch the bus space I/O to the
one specific for either the SMI or TCO space. Re-calibrate
the tick. Add some more device id's, 82801FBR submitted by des.
This makes it work on the platforms I've tested with.
Go ahead by: des
should fix strange link state behaviour reported for bcm5721 & bcm5704c
2) Clear bge_link flag in bge_stop()
3) Force link state check after bge_ifmedia_upd(). Otherwise we can miss link
event if PHY changes it's state fast enough.
Tested by: phk (bcm5704c)
Approved by: glebius (mentor)
MFC after: 1 week
jumbo mbuf clusters. To make the variable size clear they are named
MJUMPAGESIZE.
Having jumbo clusters with the native PAGE_SIZE is more useful than
a fixed 4k size according the device driver writers using this API.
The 9k and 16k jumbo mbuf clusters remain unchanged.
Requested by: glebius, gallatin
Sponsored by: TCP/IP Optimization Fundraise 2005
MFC after: 3 days
Acknowledgement should definitly go to JMicron Technology for providing full
docs on the metadata format as the only vendor so far, big thanks from here.
threshold. Inflight doesn't make sense on a LAN as it has
trouble figuring out the maximal bandwidth because of the coarse
tick granularity.
The sysctl net.inet.tcp.inflight.rttthresh specifies the threshold
in milliseconds below which inflight will disengage. It defaults
to 10ms.
Tested by: Joao Barros <joao.barros-at-gmail.com>,
Rich Murphey <rich-at-whiteoaklabs.com>
Sponsored by: TCP/IP Optimization Fundraise 2005
suspension code. When a thread A is going to sleep, it calls
sleepq_catch_signals() to detect any pending signals or thread
suspension request, if nothing happens, it returns without
holding process lock or scheduler lock, this opens a race
window which allows thread B to come in and do process
suspension work, however since A is still at running state,
thread B can do nothing to A, thread A continues, and puts
itself into actually sleeping state, but B has never seen it,
and it sits there forever until B is woken up by other threads
sometimes later(this can be very long delay or never
happen). Fix this bug by forcing sleepq_catch_signals to
return with scheduler lock held.
Fix sleepq_abort() by passing it an interrupted code, previously,
it worked as wakeup_one(), and the interruption can not be
identified correctly by sleep queue code when the sleeping
thread is resumed.
Let thread_suspend_check() returns EINTR or ERESTART, so sleep
queue no longer has to use SIGSTOP as a hack to build a return
value.
Reviewed by: jhb
MFC after: 1 week
and it has not plenty of free pages it tries to free pages in the cache queue.
Unfortunately freeing a cached page requires the locking of the object that
owns the page. However in the context of allocating pages we may not be able
to lock the object and thus can only TRY to lock the object. If the locking try
fails the cache page can not be freed and is activated to move it out of the way
so that we may try to free other cache pages.
If all pages in the cache belong to objects that are currently locked the
cache queue can be emptied without freeing a single page. This scenario caused
two problems:
1) vm_page_alloc always failed allocation when it tried freeing pages from
the cache queue and failed to do so. However if there are more than
cnt.v_interrupt_free_min pages on the free list it should return pages
when requested with priority VM_ALLOC_SYSTEM. Failure to do so can cause
resource exhaustion deadlocks.
2) Threads than need to allocate pages spend a lot of time cleaning up the
page queue without really getting anything done while the pagedaemon
needs to work overtime to refill the cache.
This change fixes the first problem. (1)
Reviewed by: tegge@
