will never exit ngintr(), while there is some ready requests on the queue.
It was made years ago with hope of parallel queue processing by several
net threads. But even if we have several threads sometimes, we have no
rights to process queue in parallel as it will break original requests
serialization that is critically important for some setups.
from clearing the IFF_NEEDSGIANT flag on Giant-locked interfaces.
In particular, wpa_supplicant was doing this on USB interfaces,
causing panics when Giant-locked code was then called without Giant.
Submitted by: Alexey Popov
Reviewed by: rwatson
MFC after: 3 days
to detect (or load) kernel NLM support in rpc.lockd. Remove the '-k'
option to rpc.lockd and make kernel NLM the default. A user can still
force the use of the old user NLM by building a kernel without NFSLOCKD
and/or removing the nfslockd.ko module.
1. Add support for automatic promotion of 4KB page mappings to 2MB page
mappings. Automatic promotion can be enabled by setting the tunable
"vm.pmap.pg_ps_enabled" to a non-zero value. By default, automatic
promotion is disabled. Tested by: kris
2. To date, we have assumed that the TLB will only set the PG_M bit in a
PTE if that PTE has the PG_RW bit set. However, this assumption does
not hold on recent processors from Intel. For example, consider a PTE
that has the PG_RW bit set but the PG_M bit clear. Suppose this PTE
is cached in the TLB and later the PG_RW bit is cleared in the PTE,
but the corresponding TLB entry is not (yet) invalidated.
Historically, upon a write access using this (stale) TLB entry, the
TLB would observe that the PG_RW bit had been cleared and initiate a
page fault, aborting the setting of the PG_M bit in the PTE. Now,
however, P4- and Core2-family processors will set the PG_M bit before
observing that the PG_RW bit is clear and initiating a page fault. In
other words, the write does not occur but the PG_M bit is still set.
The real impact of this difference is not that great. Specifically,
we should no longer assert that any PTE with the PG_M bit set must
also have the PG_RW bit set, and we should ignore the state of the
PG_M bit unless the PG_RW bit is set.
The current FreeBSD syscall generation script uses all 20 and I need
another open file.
It's a shame that something named as the 'one-true-awk' is so limited
by an old denition like FOPEN_MAX when it could just make the file
handling dynamic.
This is done to avoid touching contrib sources on a vendor branch.
frequency generation and what frequency the generated was anyones
guess.
In general the 32.768kHz RTC clock x-tal was the best, because that
was a regular wrist-watch Xtal, whereas the X-tal generating the
ISA bus frequency was much lower quality, often costing as much as
several cents a piece, so it made good sense to check the ISA bus
frequency against the RTC clock.
The other relevant property of those machines, is that they
typically had no more than 16MB RAM.
These days, CPU chips croak if their clocks are not tightly within
specs and all necessary frequencies are derived from the master
crystal by means if PLL's.
Considering that it takes on average 1.5 second to calibrate the
frequency of the i8254 counter, that more likely than not, we will
not actually use the result of the calibration, and as the final
clincher, we seldom use the i8254 for anything besides BEL in
syscons anyway, it has become time to drop the calibration code.
If you need to tell the system what frequency your i8254 runs,
you can do so from the loader using hw.i8254.freq or using the
sysctl kern.timecounter.tc.i8254.frequency.
The timer_spkr_*() functions take care of the enabling/disabling
of the speaker.
Test on the existence of timer_spkr_*() functions, rather than
architectures.
to _ when evaluating ppp_<profile>_nat and ppp_<profile>_mode. Document
the per-profile variables.
PR: conf/121452, conf/122127 (partial)
MFC after: 1 week
zero-copy to the store buffer position on the BPF descriptor,
and the 'b' buffer as the free buffer in order to fill them in
the order documented in bpf(4).
MFC after: 4 months
Suggested by: csjp
(such as 'atime' vs 'noatime'). The filesystems will always see either
'nofoo' or 'nonofoo', never plain 'foo'. As such, their list of valid
mount options should include 'nofoo' instead of 'foo'. With this fix,
you can do 'mount -u -o atime' on a FFS filesystem that isn't marked as
noatime without getting an error. You can also update a noatime FFS
filesystem mounted via mount(2) (e.g. 6.x /sbin/mount binary) to 'atime'
using nmount(2) (e.g. 7.x /sbin/mount binary).
MFC after: 1 week
Reviewed by: crodig
these days, so de-generalize the acquire_timer/release_timer api
to just deal with speakers.
The new (optional) MD functions are:
timer_spkr_acquire()
timer_spkr_release()
and
timer_spkr_setfreq()
the last of which configures the timer to generate a tone of a given
frequency, in Hz instead of 1/1193182th of seconds.
Drop entirely timer2 on pc98, it is not used anywhere at all.
Move sysbeep() to kern/tty_cons.c and use the timer_spkr*() if
they exist, and do nothing otherwise.
Remove prototypes and empty acquire-/release-timer() and sysbeep()
functions from the non-beeping archs.
This eliminate the need for the speaker driver to know about
i8254frequency at all. In theory this makes the speaker driver MI,
contingent on the timer_spkr_*() functions existing but the driver
does not know this yet and still attaches to the ISA bus.
Syscons is more tricky, in one function, sc_tone(), it knows the hz
and things are just fine.
In the other function, sc_bell() it seems to get the period from
the KDMKTONE ioctl in terms if 1/1193182th second, so we hardcode
the 1193182 and leave it at that. It's probably not important.
Change a few other sysbeep() uses which obviously knew that the
argument was in terms of i8254 frequency, and leave alone those
that look like people thought sysbeep() took frequency in hertz.
This eliminates the knowledge of i8254_freq from all but the actual
clock.c code and the prof_machdep.c on amd64 and i386, where I think
it would be smart to ask for help from the timecounters anyway [TBD].
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.
Highlights include:
* Thread-safe kernel RPC client - many threads can use the same RPC
client handle safely with replies being de-multiplexed at the socket
upcall (typically driven directly by the NIC interrupt) and handed
off to whichever thread matches the reply. For UDP sockets, many RPC
clients can share the same socket. This allows the use of a single
privileged UDP port number to talk to an arbitrary number of remote
hosts.
* Single-threaded kernel RPC server. Adding support for multi-threaded
server would be relatively straightforward and would follow
approximately the Solaris KPI. A single thread should be sufficient
for the NLM since it should rarely block in normal operation.
* Kernel mode NLM server supporting cancel requests and granted
callbacks. I've tested the NLM server reasonably extensively - it
passes both my own tests and the NFS Connectathon locking tests
running on Solaris, Mac OS X and Ubuntu Linux.
* Userland NLM client supported. While the NLM server doesn't have
support for the local NFS client's locking needs, it does have to
field async replies and granted callbacks from remote NLMs that the
local client has contacted. We relay these replies to the userland
rpc.lockd over a local domain RPC socket.
* Robust deadlock detection for the local lock manager. In particular
it will detect deadlocks caused by a lock request that covers more
than one blocking request. As required by the NLM protocol, all
deadlock detection happens synchronously - a user is guaranteed that
if a lock request isn't rejected immediately, the lock will
eventually be granted. The old system allowed for a 'deferred
deadlock' condition where a blocked lock request could wake up and
find that some other deadlock-causing lock owner had beaten them to
the lock.
* Since both local and remote locks are managed by the same kernel
locking code, local and remote processes can safely use file locks
for mutual exclusion. Local processes have no fairness advantage
compared to remote processes when contending to lock a region that
has just been unlocked - the local lock manager enforces a strict
first-come first-served model for both local and remote lockers.
Sponsored by: Isilon Systems
PR: 95247 107555 115524 116679
MFC after: 2 weeks
sort the entry into it's correct place (behind 200407XX before
200406XX because we have an explicit date here).
PR: misc/122098
Submitted by: "John Hein" <jhein@timing.com>
MFC after: 3 days
the owner of a queue to block and unblock execution of the tasks in the
queue while allowing tasks to continue to be added queue. Combining this
with taskqueue_drain() allows a queue to be safely disabled. The unblock
function may run (or schedule to run) the queue when it is called, just as
calling taskqueue_enqueue() would.
Reviewed by: jhb, sam
