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freebsd/sys/i386/include/lock.h
John Baldwin 6c56727456 - Change fast interrupts on x86 to push a full interrupt frame and to
return through doreti to handle ast's.  This is necessary for the
  clock interrupts to work properly.
- Change the clock interrupts on the x86 to be fast instead of threaded.
  This is needed because both hardclock() and statclock() need to run in
  the context of the current process, not in a separate thread context.
- Kill the prevproc hack as it is no longer needed.
- We really need Giant when we call psignal(), but we don't want to block
  during the clock interrupt.  Instead, use two p_flag's in the proc struct
  to mark the current process as having a pending SIGVTALRM or a SIGPROF
  and let them be delivered during ast() when hardclock() has finished
  running.
- Remove CLKF_BASEPRI, which was #ifdef'd out on the x86 anyways.  It was
  broken on the x86 if it was turned on since cpl is gone.  It's only use
  was to bogusly run softclock() directly during hardclock() rather than
  scheduling an SWI.
- Remove the COM_LOCK simplelock and replace it with a clock_lock spin
  mutex.  Since the spin mutex already handles disabling/restoring
  interrupts appropriately, this also lets us axe all the *_intr() fu.
- Back out the hacks in the APIC_IO x86 cpu_initclocks() code to use
  temporary fast interrupts for the APIC trial.
- Add two new process flags P_ALRMPEND and P_PROFPEND to mark the pending
  signals in hardclock() that are to be delivered in ast().

Submitted by:	jakeb (making statclock safe in a fast interrupt)
Submitted by:	cp (concept of delaying signals until ast())
2000-10-06 02:20:21 +00:00

132 lines
3.4 KiB
C

/*
* Copyright (c) 1997, by Steve Passe
* 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. The name of the developer may NOT be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#ifndef _MACHINE_LOCK_H_
#define _MACHINE_LOCK_H_
#ifdef LOCORE
#ifdef SMP
#define MPLOCKED lock ;
/*
* Protects the IO APIC and apic_imen as a critical region.
*/
#define IMASK_LOCK \
pushl $_imen_lock ; /* address of lock */ \
call _s_lock ; /* MP-safe */ \
addl $4, %esp
#define IMASK_UNLOCK \
movl $0, _imen_lock
#else /* SMP */
#define MPLOCKED /* NOP */
#define IMASK_LOCK /* NOP */
#define IMASK_UNLOCK /* NOP */
#endif /* SMP */
#else /* LOCORE */
#ifdef SMP
#include <machine/smptests.h> /** xxx_LOCK */
/*
* sio/cy lock.
* XXX should rc (RISCom/8) use this?
*/
#ifdef USE_COMLOCK
#define COM_LOCK() s_lock(&com_lock)
#define COM_UNLOCK() s_unlock(&com_lock)
#else
#define COM_LOCK()
#define COM_UNLOCK()
#endif /* USE_COMLOCK */
#else /* SMP */
#define COM_LOCK()
#define COM_UNLOCK()
#endif /* SMP */
/*
* Simple spin lock.
* It is an error to hold one of these locks while a process is sleeping.
*/
struct simplelock {
volatile int lock_data;
};
/* functions in simplelock.s */
void s_lock_init __P((struct simplelock *));
void s_lock __P((struct simplelock *));
int s_lock_try __P((struct simplelock *));
void ss_lock __P((struct simplelock *));
void ss_unlock __P((struct simplelock *));
void s_lock_np __P((struct simplelock *));
void s_unlock_np __P((struct simplelock *));
/* inline simplelock functions */
static __inline void
s_unlock(struct simplelock *lkp)
{
lkp->lock_data = 0;
}
/* global data in mp_machdep.c */
extern struct simplelock imen_lock;
extern struct simplelock cpl_lock;
extern struct simplelock fast_intr_lock;
extern struct simplelock intr_lock;
extern struct simplelock com_lock;
extern struct simplelock mpintr_lock;
extern struct simplelock mcount_lock;
extern struct simplelock panic_lock;
#if !defined(SIMPLELOCK_DEBUG) && MAXCPU > 1
/*
* This set of defines turns on the real functions in i386/isa/apic_ipl.s.
*/
#define simple_lock_init(alp) s_lock_init(alp)
#define simple_lock(alp) s_lock(alp)
#define simple_lock_try(alp) s_lock_try(alp)
#define simple_unlock(alp) s_unlock(alp)
#endif /* !SIMPLELOCK_DEBUG && MAXCPU > 1 */
#endif /* LOCORE */
#endif /* !_MACHINE_LOCK_H_ */