1300c5d089
New make target of "make depend" Addition of doxygen building ability Cleanup of docygen comment blocks Initial telnetd protocol module structure
101 lines
2.0 KiB
C
101 lines
2.0 KiB
C
/*
|
|
* This file is distributed as part of the SkySQL Gateway. It is free
|
|
* software: you can redistribute it and/or modify it under the terms of the
|
|
* GNU General Public License as published by the Free Software Foundation,
|
|
* version 2.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
|
* details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along with
|
|
* this program; if not, write to the Free Software Foundation, Inc., 51
|
|
* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*
|
|
* Copyright SkySQL Ab 2013
|
|
*/
|
|
|
|
/**
|
|
* @file spinlock.c - Spinlock operations for the SkySQL Gateway
|
|
*
|
|
* @verbatim
|
|
* Revision History
|
|
*
|
|
* Date Who Description
|
|
* 10/06/13 Mark Riddoch Initial implementation
|
|
*
|
|
* @endverbatim
|
|
*/
|
|
|
|
#include <spinlock.h>
|
|
#include <atomic.h>
|
|
|
|
/**
|
|
* Initialise a spinlock.
|
|
*
|
|
* @param lock The spinlock to initialise.
|
|
*/
|
|
void
|
|
spinlock_init(SPINLOCK *lock)
|
|
{
|
|
lock->lock = 0;
|
|
#ifdef DEBUG
|
|
lock->spins = 0;
|
|
lock->acquired = 0;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* Acquire a spinlock.
|
|
*
|
|
* @param lock The spinlock to acquire
|
|
*/
|
|
void
|
|
spinlock_acquire(SPINLOCK *lock)
|
|
{
|
|
while (atomic_add(&(lock->lock), 1) != 0)
|
|
{
|
|
atomic_add(&(lock->lock), -1);
|
|
#ifdef DEBUG
|
|
atomic_add(&(lock->spins), 1);
|
|
#endif
|
|
}
|
|
#ifdef DEBUG
|
|
lock->acquired++;
|
|
lock->owner = THREAD_SHELF();
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* Acquire a spinlock if it is not already locked.
|
|
*
|
|
* @param lock The spinlock to acquire
|
|
* @return True ifthe spinlock was acquired, otherwise false
|
|
*/
|
|
int
|
|
spinlock_acquire_nowait(SPINLOCK *lock)
|
|
{
|
|
if (atomic_add(&(lock->lock), 1) != 0)
|
|
{
|
|
atomic_add(&(lock->lock), -1);
|
|
return FALSE;
|
|
}
|
|
#ifdef DEBUG
|
|
lock->acquired++;
|
|
lock->owner = THREAD_SHELF();
|
|
#endif
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* Release a spinlock.
|
|
*
|
|
* @param lock The spinlock to release
|
|
*/
|
|
void
|
|
spinlock_release(SPINLOCK *lock)
|
|
{
|
|
atomic_add(&(lock->lock), -1);
|
|
}
|