Implement RCU mechanism using shared exclusive locks.

MFC after:	1 week
Sponsored by:	Mellanox Technologies
This commit is contained in:
Hans Petter Selasky 2016-01-05 12:22:45 +00:00
parent 623534d683
commit e10c4cc0a4
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=293194
2 changed files with 84 additions and 1 deletions

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@ -0,0 +1,76 @@
/*-
* Copyright (c) 2016 Mellanox Technologies, Ltd.
* 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 unmodified, 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
* $FreeBSD$
*/
#ifndef _LINUX_RCUPDATE_H_
#define _LINUX_RCUPDATE_H_
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/sx.h>
extern struct sx linux_global_rcu_lock;
struct rcu_head {
};
typedef void (*rcu_callback_t)(struct rcu_head *);
static inline void
call_rcu(struct rcu_head *ptr, rcu_callback_t func)
{
sx_xlock(&linux_global_rcu_lock);
func(ptr);
sx_xunlock(&linux_global_rcu_lock);
}
static inline void
rcu_read_lock(void)
{
sx_slock(&linux_global_rcu_lock);
}
static inline void
rcu_read_unlock(void)
{
sx_sunlock(&linux_global_rcu_lock);
}
static inline void
rcu_barrier(void)
{
sx_xlock(&linux_global_rcu_lock);
sx_xunlock(&linux_global_rcu_lock);
}
static inline void
synchronize_rcu(void)
{
sx_xlock(&linux_global_rcu_lock);
sx_xunlock(&linux_global_rcu_lock);
}
#endif /* _LINUX_RCUPDATE_H_ */

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@ -2,7 +2,7 @@
* Copyright (c) 2010 Isilon Systems, Inc.
* Copyright (c) 2010 iX Systems, Inc.
* Copyright (c) 2010 Panasas, Inc.
* Copyright (c) 2013-2015 Mellanox Technologies, Ltd.
* Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@ -65,6 +65,7 @@ __FBSDID("$FreeBSD$");
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <linux/rcupdate.h>
#include <vm/vm_pager.h>
@ -84,6 +85,7 @@ struct list_head pci_drivers;
struct list_head pci_devices;
struct net init_net;
spinlock_t pci_lock;
struct sx linux_global_rcu_lock;
unsigned long linux_timer_hz_mask;
@ -1142,6 +1144,8 @@ linux_compat_init(void *arg)
struct sysctl_oid *rootoid;
int i;
sx_init(&linux_global_rcu_lock, "LinuxGlobalRCU");
rootoid = SYSCTL_ADD_ROOT_NODE(NULL,
OID_AUTO, "sys", CTLFLAG_RD|CTLFLAG_MPSAFE, NULL, "sys");
kobject_init(&linux_class_root, &linux_class_ktype);
@ -1171,6 +1175,9 @@ linux_compat_uninit(void *arg)
linux_kobject_kfree_name(&linux_class_root);
linux_kobject_kfree_name(&linux_root_device.kobj);
linux_kobject_kfree_name(&linux_class_misc.kobj);
synchronize_rcu();
sx_destroy(&linux_global_rcu_lock);
}
SYSUNINIT(linux_compat, SI_SUB_DRIVERS, SI_ORDER_SECOND, linux_compat_uninit, NULL);