From 859e500fd86c20e7841fd6dd2d63d21c3dd4225c Mon Sep 17 00:00:00 2001 From: Ian Moffett Date: Fri, 26 Apr 2024 14:26:48 -0400 Subject: kernel: Add support for mutex locks Signed-off-by: Ian Moffett --- sys/include/sys/mutex.h | 42 +++++++++++++++++++++++++++++++++++++++ sys/kern/kern_mutex.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 94 insertions(+) create mode 100644 sys/include/sys/mutex.h create mode 100644 sys/kern/kern_mutex.c diff --git a/sys/include/sys/mutex.h b/sys/include/sys/mutex.h new file mode 100644 index 0000000..dfd2dec --- /dev/null +++ b/sys/include/sys/mutex.h @@ -0,0 +1,42 @@ +/* + * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include + +#ifndef _SYS_MUTEX_H_ +#define _SYS_MUTEX_H_ + +struct mutex { + volatile _Atomic bool lock; +}; + +void mutex_acquire(struct mutex *mutex); +void mutex_release(struct mutex *mutex); + +#endif /* !_SYS_MUTEX_H_ */ diff --git a/sys/kern/kern_mutex.c b/sys/kern/kern_mutex.c new file mode 100644 index 0000000..ea770b1 --- /dev/null +++ b/sys/kern/kern_mutex.c @@ -0,0 +1,52 @@ +/* + * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include +#include + +void +mutex_acquire(struct mutex *mutex) +{ + struct proc *td = this_td(); + register bool rest = (td != NULL); + + while (__atomic_test_and_set(&mutex->lock, __ATOMIC_ACQUIRE)) { + if (!rest) + continue; + + sched_rest(); + } +} + +void +mutex_release(struct mutex *mutex) +{ + __atomic_clear(&mutex->lock, __ATOMIC_RELEASE); +} -- cgit v1.2.3