return -1 on error while any other return value from it can
indicate success. (See RETURN VALUE in our ioctl(2) manpage
and the POSIX spec.)
- Avoid assumptions about the state of the data buffer after
ioctl(2) failure.
Add a new option to newfs(8), -r, to specify reserved space at the
end of the device. It can be useful, e.g., when the device is to
become a member of a gmirror array later w/o losing the file system
on it.
Document the new option in the manpage.
While I'm here, improve error handling for -s option, which is
syntactically similar to -r; and document the fact that -s0 selects
the default fs size explicitly, which can be useful, e.g., in a
menu-based wrapper around newfs(8) requiring some value be entered
for the fs size.
Also fix a small typo in the help line for -s (missing space).
Idea and initial implementation by: marck
Discussed on: -fs
Critical review by: bde
Tested with: cmp(1)
Currently, Giant is not too much contented so that it is ok to treact it
like any other mutexes.
Please don't forget to update your own custom config kernel files.
Approved by: cognet, marcel (maintainers of arches where option is
not enabled at the moment)
of some old programs. Since sigval is union type, this change will not have
binary compatibility problem.
MFC: after 3 days
Discussed with: rwatson, glebius
It should just contain the value we want to add, as if we're interrupted
between the add and the str, we will restart from the beginning. Just use
a register we can scratch instead.
MFC After: 1 week
routine. It is not needed as the existing tests for segment coalescing
already handle bounced addresses and it prevents legal segment coalescing
in certain edge cases.
MFC after: 1 week
Reviewed by: scottl
20071120 shared library version bump.
Update the date in the comments to match the date of the actual
commit.
Approved by: bz, erwin (mentor)
MFC after: 3 days
The call should happen with the driver lock held. We don't hold the driver
lock in newstate as it's a separate thread where we can't sleep (and we only
call wpi_cmd in async mode).
Discovered By: Attillo's callout rework
Approved By: mlaier (comentor)
contention. The intent is to dynamically adjust to load imbalances, which
can cause severe contention.
Use pthread mutexes where possible instead of libc "spinlocks" (they aren't
actually spin locks). Conceptually, this change is meant only to support
the dynamic load balancing code by enabling the use of spin locks, but it
has the added apparent benefit of substantially improving performance due to
reduced context switches when there is moderate arena lock contention.
Proper tuning parameter configuration for this change is a finicky business,
and it is very much machine-dependent. One seemingly promising solution
would be to run a tuning program during operating system installation that
computes appropriate settings for load balancing. (The pthreads adaptive
spin locks should probably be similarly tuned.)
vector of slots for lazily freed objects. For each deallocation, before
doing the hard work of locking the arena and deallocating, try several times
to randomly insert the object into the vector using atomic operations.
This approach is particularly effective at reducing contention for
multi-threaded applications that use the producer-consumer model, wherein
one producer thread allocates objects, then multiple consumer threads
deallocate those objects.
allocations. [1]
Fix calculation of the number of arenas when 'n' is specified via
MALLOC_OPTIONS.
Clean up various style inconsistencies.
Obtained from: [1] NetBSD
currently, before to spin the turnstile spinlock is acquired and the
waiters flag is set.
This is not strictly necessary, so just spin before to acquire the
spinlock and to set the flags.
This will simplify a lot other functions too, as now we have the waiters
flag set only if there are actually waiters.
This should make wakeup/sleeping couplet faster under intensive mutex
workload.
This also fixes a bug in rw_try_upgrade() in the adaptive case, where
turnstile_lookup() will recurse on the ts_lock lock that will never be
really released [1].
[1] Reported by: jeff with Nokia help
Tested by: pho, kris (earlier, bugged version of rwlock part)
Discussed with: jhb [2], jeff
MFC after: 1 week
[2] John had a similar patch about 6.x and/or 7.x about mutexes probabilly
in the default CFLAGS, we're in the middle of a ports freeze, so we can't
really go making the corresponding change to the ports mk files.
I'll take -fno-strict-aliasing out again when the ports freeze ends.
sends frames up the stack after changing the current channel then
the lookup by ieee channel number may fail leaving a null ptr in
se_chan; if this happens fallback to the channel recorded when the
frame is processed (curchan). Since the frame doesn't contribute
to scan results for the sta this is acceptable.
Reviewed by: thompsa
MFC after: 3 days
