openat() and the related syscalls.
Based on the submission by rdivacky,
sponsored by Google Summer of Code 2007
Reviewed by: rwatson, rdivacky
Tested by: pho
to protect the v_lock pointer. Removing the interlock acquisition
here allows vn_lock() to proceed without requiring the interlock
at all.
- If the lock mutated while we were sleeping on it the interlock has
been dropped. It is conceivable that the upper layer code was
relying on the interlock and LK_NOWAIT to protect the identity or
state of the vnode while acquiring the lock. In this case return
EBUSY rather than trying the new lock to prevent potential races.
Reviewed by: tegge
Keeping the lockmgr lock valid allows us to switch the v_lock pointer
in snapshot vnodes between the embedded lockmgr lock and snapdata
lock without needing the vnode interlock to protect against races
- Keep unused snapdata structures in a list.
- Add a function to lock the devvp and allocate a snapdata to it or
acquire a new one without races. The old function was safe from
creation races because we set the mount flag when creating snapshots
and thus serializing them. However, it might have been subject to
destroying races.
Reviewed by: tegge
was a kluge. This implementation matches the behaviour on powerpc
and sparc64.
While on the subject, make sure to invalidate the I-cache after
loading a kernel module.
MFC after: 2 weeks
incompatible with existing bindings.
- Try to copyout the setid in cpuset() before migrating the proc to the
setid in case the user has supplied a bad buffer.
- Rename cpuset_root() and cpuset_base() to cpuset_ref{root,base} to
be more descriptive and free cpuset_root to be used as a different
type of symbol.
- Make cpuset_root the cpuset_t set of all cpus in the system. This
should contain the same bitmask as all_cpus presently.
- Add a CPU_CMP() macro to compare two sets.
- Do not check destination hook presence, it will be done by netgraph.
- Use u_int instead of int in some places to simplify type conversions.
- Use NG_SEND_DATA_ONLY() macro instead of selfmade equivalent.
which simply want a reference should use vref(). Callers which want
to check validity need to hold a lock while performing any action
based on that validity. vn_lock() would always release the interlock
before returning making any action synchronous with the validity check
impossible.
SI_SUB_DRIVERS) to avoid loading schemes before all the GEOM
classes have been loaded and initialized. Otherwise we may
end up using mutexes that haven't been initialized (due to
g_retaste() posting an event).
vm_object_reference(). This is intended to get rid of vget()
consumers who don't wish to acquire a lock. This is functionally
the same as calling vref(). vm_object_reference_locked() already
uses vref.
Discussed with: alc
and netgraph in gernal). This also allows to add queues for an interface
that is not yet existing (you have to provide the bandwidth for the
interface, however).
PR: kern/106400, kern/117827
MFC after: 2 weeks
dropped after the call to lockmgr() so just revert this approach using
something similar to the precedent one:
BUF_LOCKWAITERS() just checks if there are waiters (not the actual number
of them) and it is based on newly introduced lockmgr_waiters() which
returns if the lockmgr has waiters or not. The name has been choosen
differently by old lockwaiters() in order to not confuse them.
KPI results enriched by this commit so __FreeBSD_version bumping and
manpage update will be happening soon.
'struct buf' also changes, so kernel ABI is disturbed.
Bug found by: jeff
Approved by: jeff, kib
allows the class to create a different GEOM for the same provider
as well as avoid that we end up with multiple GEOMs of the same
class with the same name.
For example, when a disk contains a PC98 partition table but
only MBR is supported, then the partition table can be treated
as a MBR. If support for PC98 is later loaded as a module, the
MBR scheme is pre-empted for the PC98 scheme as expected.
offload bugs by manual padding for short IP/UDP frames. Unfortunately
it seems that these workaround does not work reliably on newer PCIe
variants of RealTek chips.
To workaround the hardware bug, always pad short frames if Tx IP
checksum offload is requested. It seems that the hardware has a
bug in IP checksum offload handling. NetBSD manually pads short
frames only when the length of IP frame is less than 28 bytes but I
chose 60 bytes to safety. Also unconditionally set IP checksum
offload bit in Tx descriptor if any TCP or UDP checksum offload is
requested. This is the same way as Linux does but it's not
mentioned in data sheet.
Obtained from: NetBSD
Tested by: remko, danger
src/cddl and src/sys/cddl directories per the core@ decision following
the license review.
This change modifies the affected Makefiles to reference the sources
in their new location.
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.
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.
