the mutex locked. Also tweak the wording to make it more consistant
between pthread_cond_wait and pthread_cond_tiedwait.
Confirmed with the opengroup's web site that this is a valid return
value. Wording used specifically not that of opengroup's online man
pages.
MFC After: 1 week
imitating an Ethernet device, so vlan(4) and if_bridge(4) can be
attached to it for testing and benchmarking purposes. Its source
can be an introduction to the anatomy of a network interface driver
due to its simplicity as well as to a bunch of comments in it.
argument from a mutex to a lock_object. Add cv_*wait*() wrapper macros
that accept either a mutex, rwlock, or sx lock as the second argument and
convert it to a lock_object and then call _cv_*wait*(). Basically, the
visible difference is that you can now use rwlocks and sx locks with
condition variables using the same API as with mutexes.
This is supposed to be a brief overview of the locking primatives.
It is not yet complete and contains many place-holders for information
I do not know.
The locking is getting so diverse that I've lost track of it all.
We need this page to keep outselves in sync with what the primitives do.
note.. not part of the build yet.
the background fsck indefinitely. This allows the administrator to run
it at a convenient time. To support running it from cron, the
forcestart argument now causes the fsck to start with no delay and all
output to be suppressed.
event. Locking primitives that support this (mtx, rw, and sx) now each
include their own foo_sleep() routine.
- Rename msleep() to _sleep() and change it's 'struct mtx' object to a
'struct lock_object' pointer. _sleep() uses the recently added
lc_unlock() and lc_lock() function pointers for the lock class of the
specified lock to release the lock while the thread is suspended.
- Add wrappers around _sleep() for mutexes (mtx_sleep()), rw locks
(rw_sleep()), and sx locks (sx_sleep()). msleep() still exists and
is now identical to mtx_sleep(), but it is deprecated.
- Rename SLEEPQ_MSLEEP to SLEEPQ_SLEEP.
- Rewrite much of sleep.9 to not be msleep(9) centric.
- Flesh out the 'RETURN VALUES' section in sleep.9 and add an 'ERRORS'
section.
- Add __nonnull(1) to _sleep() and msleep_spin() so that the compiler will
warn if you try to pass a NULL wait channel. The functions already have
a KASSERT to that effect.
interrupt sleeps. Rather, unmasked signals interrupt restarts and can
either interrupt the system call by having it return EINTR in userland or
force the system call to be restarted.
- Don't claim that the mutex is atomically reacquired when a cv_wait
routine returns. There's nothing atomic or magical about the lock
reacquire. The only magic is that we atomically drop the lock by
placing the thread on the sleep queue before dropping the lock.
- Markup sx_unlock() as a function rather than saying it is a macro.
The macro part is an implementation detail, and all the other sx_*lock()
functions are actually macros, too.
- Use the same style as rwlock(9) and mutex(9) to markup sx_assert() and
SX_SYSINIT() with respect to headers and kernel options.
- Add a missing MLINK.