SLEEP_LOCK_SIG(D3)SLEEP_LOCK_SIG(D3)NAMESLEEP_LOCK_SIG - acquire a sleep lock
SYNOPSIS
#include <sys/types.h>
#include <sys/ksynch.h>
#include <sys/ddi.h>
#include <sys/param.h>
boolean_t SLEEP_LOCK_SIG(sleep_t *lockp, int priority);
Arguments
lockp Pointer to the sleep lock to be acquired.
priority A hint to the scheduling policy as to the relative priority the
caller wishes to be assigned while running in the kernel after
waking up.
DESCRIPTIONSLEEP_LOCK_SIG acquires the sleep lock specified by lockp. If the lock
is not immediately available, the caller is put to sleep (the caller's
execution is suspended and other processes may be scheduled) until the
lock becomes available to the caller, at which point the caller wakes up
and returns with the lock held.
SLEEP_LOCK_SIG may be interrupted by a signal, in which case it may
return early without acquiring the lock.
If the function is interrupted by a job control stop signal (e.g.,
SIGSTOP, SIGTSTP, SIGTTIN, SIGTTOU) which results in the caller entering
a stopped state, the SLEEP_LOCK_SIG function will transparently retry the
lock operation upon continuing (the call will not return without the
lock).
If the function is interrupted by a signal other than a job control stop
signal, or by a job control stop signal that does not result in the
caller stopping (because the signal has a non-default disposition), the
SLEEP_LOCK_SIG call will return early without acquiring the lock.
Return Values
SLEEP_LOCK_SIG returns TRUE (a non-zero value) if the lock is
successfully acquired or FALSE (zero) if the function returned early
because of a signal.
USAGE
Priority Argument
In general, a lower value will result in more favorable scheduling
although the exact semantic of the priority argument is specific to the
scheduling class of the caller, and some scheduling classes may choose to
ignore the argument for the purposes of assigning a scheduling priority.
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SLEEP_LOCK_SIG(D3)SLEEP_LOCK_SIG(D3)
The value of priority must be greater than PZERO (defined in sys/param.h)
In general, a higher relative priority should be used when the caller is
attempting to acquire a highly contended lock or resource,or when the
caller is already holding one or more locks or kernel resources upon
entry to SLEEP_LOCK_SIG.
Level
Base only.
Synchronization Constraints
Can sleep.
Driver-defined basic locks and read/write locks may not be held across
calls to this function.
Driver-defined sleep locks may be held across calls to this function
subject to the recursion restrictions described below.
Warnings
Sleep locks are not recursive. A call to SLEEP_LOCK_SIG attempting to
acquire a lock that is currently held by the calling context will result
in deadlock.
REFERENCESSLEEP_ALLOC(D3), SLEEP_INIT(D3), SLEEP_DEALLOC(D3), SLEEP_DESTROY(D3),
SLEEP_LOCK(D3), SLEEP_LOCKAVAIL(D3), SLEEP_TRYLOCK(D3), SLEEP_UNLOCK(D3),
signals(D5).
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