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wait_event_lock_irq_cmd(9) [centos man page]

WAIT_EVENT_LOCK_IRQ_(9) 					   Driver Basics					   WAIT_EVENT_LOCK_IRQ_(9)

NAME
wait_event_lock_irq_cmd - sleep until a condition gets true. The condition is checked under the lock. This is expected to be called with the lock taken. SYNOPSIS
wait_event_lock_irq_cmd(wq, condition, lock, cmd); ARGUMENTS
wq the waitqueue to wait on condition a C expression for the event to wait for lock a locked spinlock_t, which will be released before cmd and schedule and reacquired afterwards. cmd a command which is invoked outside the critical section before sleep DESCRIPTION
The process is put to sleep (TASK_UNINTERRUPTIBLE) until the condition evaluates to true. The condition is checked each time the waitqueue wq is woken up. wake_up has to be called after changing any variable that could change the result of the wait condition. This is supposed to be called while holding the lock. The lock is dropped before invoking the cmd and going to sleep and is reacquired afterwards. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 WAIT_EVENT_LOCK_IRQ_(9)

Check Out this Related Man Page

tis_read_trylock(3)					     Library Functions Manual					       tis_read_trylock(3)

NAME
tis_read_trylock - Attempts to acquire a read-write lock for read access. Does not wait if the lock cannot be immediately granted. LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <tis.h> int tis_read_trylock( tis_rwlock_t *lock); STANDARDS
None PARAMETERS
Address of the read-write lock to be acquired. DESCRIPTION
This routine attempts to acquire a read-write lock for read access. If the lock cannot be granted, the routine returns without waiting. When a thread calls this routine, an attempt is made to immediately acquire the lock for read access. If the lock is acquired, zero (0) is returned. If a holder of the lock for write access exists, [EBUSY] is returned. If the lock cannot be acquired for read access immediately, the calling program does not wait for the lock to be released. RETURN VALUES
If an error condition occurs, this routine returns an integer value indicating the type of error. Possible return values are as follows: Successful completion; the lock was acquired. The lock is being held for write access. The lock for read access was not acquired. ERRORS
None RELATED INFORMATION
Functions: tis_read_lock(3), tis_read_unlock(3), tis_rwlock_destroy(3), tis_rwlock_init(3), tis_write_lock(3), tis_write_trylock(3), tis_write_unlock(3) Manuals: Guide to DECthreads and Programmer's Guide delim off tis_read_trylock(3)

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