freebsd-skq/sys/i386/isa/ithread.c
jhb ca00514d9e - Add a new ithread_schedule() function to do the bulk of the work of
scheduling an interrupt thread to run when needed.  This has the side
  effect of enabling support for entropy gathering from interrupts on
  all architectures.
- Change the software interrupt and x86 and alpha hardware interrupt code
  to use ithread_schedule() for most of their processing when scheduling
  an interrupt to run.
- Remove the pesky Warning message about interrupt threads having entropy
  enabled.  I'm not sure why I put that in there in the first place.
- Add more error checking for parameters and change some cases that
  returned EINVAL to panic on failure instead via KASSERT().
- Instead of doing a documented evil hack of setting the P_NOLOAD flag
  on every interrupt thread whose pri was SWI_CLOCK, set the flag
  explicity for clk_ithd's proc during start_softintr().
2001-02-20 10:25:29 +00:00

113 lines
3.5 KiB
C

/*-
* Copyright (c) 1997 Berkeley Software Design, Inc. 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. Berkeley Software Design Inc's name may not be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``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 BERKELEY SOFTWARE DESIGN INC 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.
*
* From BSDI: intr.c,v 1.6.2.5 1999/07/06 19:16:52 cp Exp
* $FreeBSD$
*/
/* Interrupt thread code. */
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/rtprio.h> /* change this name XXX */
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/syslog.h>
#include <sys/ipl.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/unistd.h>
#include <sys/errno.h>
#include <sys/interrupt.h>
#include <sys/random.h>
#include <sys/resourcevar.h>
#include <sys/time.h>
#include <machine/md_var.h>
#include <machine/segments.h>
#include <i386/isa/icu.h>
#include <isa/isavar.h>
#include <i386/isa/intr_machdep.h>
#include <sys/interrupt.h>
#include <sys/vmmeter.h>
#include <sys/ktr.h>
#include <machine/cpu.h>
struct int_entropy {
struct proc *p;
int irq;
};
static u_int straycount[NHWI];
#define MAX_STRAY_LOG 5
/*
* Schedule a heavyweight interrupt process. This function is called
* from the interrupt handlers Xintr<num>.
*/
void
sched_ithd(void *cookie)
{
int irq = (int) cookie; /* IRQ we're handling */
struct ithd *ithd = ithds[irq]; /* and the process that does it */
int error;
/* This used to be in icu_vector.s */
/*
* We count software interrupts when we process them. The
* code here follows previous practice, but there's an
* argument for counting hardware interrupts when they're
* processed too.
*/
atomic_add_long(intr_countp[irq], 1); /* one more for this IRQ */
atomic_add_int(&cnt.v_intr, 1); /* one more global interrupt */
/*
* Schedule the interrupt thread to run if needed and switch to it
* if we schedule it if !cold.
*/
error = ithread_schedule(ithd, !cold);
/*
* Log stray interrupts.
*/
if (error == EINVAL)
if (straycount[irq] < MAX_STRAY_LOG) {
printf("stray irq %d\n", irq);
if (++straycount[irq] == MAX_STRAY_LOG)
printf(
"got %d stray irq %d's: not logging anymore\n",
MAX_STRAY_LOG, irq);
}
}