user-space Linux compatibility support. No functional change. MFC after: 1 week Sponsored by: Mellanox Technologies // NVIDIA Networking
1670 lines
40 KiB
C
1670 lines
40 KiB
C
/*-
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* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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*
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* Copyright (c) 1997, Stefan Esser <se@freebsd.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice unmodified, this list of conditions, and the following
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* disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "opt_ddb.h"
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#include "opt_kstack_usage_prof.h"
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#include <sys/param.h>
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#include <sys/bus.h>
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#include <sys/conf.h>
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#include <sys/cpuset.h>
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#include <sys/rtprio.h>
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#include <sys/systm.h>
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#include <sys/interrupt.h>
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#include <sys/kernel.h>
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#include <sys/kthread.h>
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#include <sys/ktr.h>
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#include <sys/limits.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#include <sys/mutex.h>
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#include <sys/priv.h>
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#include <sys/proc.h>
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#include <sys/epoch.h>
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#include <sys/random.h>
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#include <sys/resourcevar.h>
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#include <sys/sched.h>
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#include <sys/smp.h>
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#include <sys/sysctl.h>
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#include <sys/syslog.h>
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#include <sys/unistd.h>
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#include <sys/vmmeter.h>
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#include <machine/atomic.h>
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#include <machine/cpu.h>
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#include <machine/md_var.h>
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#include <machine/smp.h>
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#include <machine/stdarg.h>
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#ifdef DDB
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#include <ddb/ddb.h>
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#include <ddb/db_sym.h>
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#endif
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/*
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* Describe an interrupt thread. There is one of these per interrupt event.
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*/
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struct intr_thread {
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struct intr_event *it_event;
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struct thread *it_thread; /* Kernel thread. */
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int it_flags; /* (j) IT_* flags. */
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int it_need; /* Needs service. */
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};
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/* Interrupt thread flags kept in it_flags */
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#define IT_DEAD 0x000001 /* Thread is waiting to exit. */
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#define IT_WAIT 0x000002 /* Thread is waiting for completion. */
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struct intr_entropy {
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struct thread *td;
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uintptr_t event;
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};
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struct intr_event *clk_intr_event;
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struct intr_event *tty_intr_event;
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void *vm_ih;
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struct proc *intrproc;
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static MALLOC_DEFINE(M_ITHREAD, "ithread", "Interrupt Threads");
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static int intr_storm_threshold = 0;
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SYSCTL_INT(_hw, OID_AUTO, intr_storm_threshold, CTLFLAG_RWTUN,
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&intr_storm_threshold, 0,
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"Number of consecutive interrupts before storm protection is enabled");
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static int intr_epoch_batch = 1000;
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SYSCTL_INT(_hw, OID_AUTO, intr_epoch_batch, CTLFLAG_RWTUN, &intr_epoch_batch,
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0, "Maximum interrupt handler executions without re-entering epoch(9)");
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static TAILQ_HEAD(, intr_event) event_list =
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TAILQ_HEAD_INITIALIZER(event_list);
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static struct mtx event_lock;
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MTX_SYSINIT(intr_event_list, &event_lock, "intr event list", MTX_DEF);
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static void intr_event_update(struct intr_event *ie);
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static int intr_event_schedule_thread(struct intr_event *ie);
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static struct intr_thread *ithread_create(const char *name);
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static void ithread_destroy(struct intr_thread *ithread);
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static void ithread_execute_handlers(struct proc *p,
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struct intr_event *ie);
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static void ithread_loop(void *);
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static void ithread_update(struct intr_thread *ithd);
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static void start_softintr(void *);
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/* Map an interrupt type to an ithread priority. */
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u_char
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intr_priority(enum intr_type flags)
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{
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u_char pri;
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flags &= (INTR_TYPE_TTY | INTR_TYPE_BIO | INTR_TYPE_NET |
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INTR_TYPE_CAM | INTR_TYPE_MISC | INTR_TYPE_CLK | INTR_TYPE_AV);
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switch (flags) {
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case INTR_TYPE_TTY:
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pri = PI_TTY;
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break;
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case INTR_TYPE_BIO:
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pri = PI_DISK;
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break;
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case INTR_TYPE_NET:
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pri = PI_NET;
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break;
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case INTR_TYPE_CAM:
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pri = PI_DISK;
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break;
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case INTR_TYPE_AV:
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pri = PI_AV;
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break;
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case INTR_TYPE_CLK:
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pri = PI_REALTIME;
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break;
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case INTR_TYPE_MISC:
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pri = PI_DULL; /* don't care */
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break;
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default:
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/* We didn't specify an interrupt level. */
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panic("intr_priority: no interrupt type in flags");
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}
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return pri;
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}
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/*
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* Update an ithread based on the associated intr_event.
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*/
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static void
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ithread_update(struct intr_thread *ithd)
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{
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struct intr_event *ie;
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struct thread *td;
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u_char pri;
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ie = ithd->it_event;
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td = ithd->it_thread;
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mtx_assert(&ie->ie_lock, MA_OWNED);
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/* Determine the overall priority of this event. */
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if (CK_SLIST_EMPTY(&ie->ie_handlers))
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pri = PRI_MAX_ITHD;
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else
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pri = CK_SLIST_FIRST(&ie->ie_handlers)->ih_pri;
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/* Update name and priority. */
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strlcpy(td->td_name, ie->ie_fullname, sizeof(td->td_name));
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#ifdef KTR
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sched_clear_tdname(td);
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#endif
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thread_lock(td);
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sched_prio(td, pri);
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thread_unlock(td);
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}
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/*
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* Regenerate the full name of an interrupt event and update its priority.
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*/
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static void
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intr_event_update(struct intr_event *ie)
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{
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struct intr_handler *ih;
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char *last;
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int missed, space, flags;
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/* Start off with no entropy and just the name of the event. */
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mtx_assert(&ie->ie_lock, MA_OWNED);
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strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname));
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flags = 0;
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missed = 0;
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space = 1;
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/* Run through all the handlers updating values. */
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CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) {
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if (strlen(ie->ie_fullname) + strlen(ih->ih_name) + 1 <
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sizeof(ie->ie_fullname)) {
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strcat(ie->ie_fullname, " ");
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strcat(ie->ie_fullname, ih->ih_name);
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space = 0;
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} else
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missed++;
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flags |= ih->ih_flags;
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}
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ie->ie_hflags = flags;
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/*
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* If there is only one handler and its name is too long, just copy in
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* as much of the end of the name (includes the unit number) as will
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* fit. Otherwise, we have multiple handlers and not all of the names
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* will fit. Add +'s to indicate missing names. If we run out of room
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* and still have +'s to add, change the last character from a + to a *.
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*/
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if (missed == 1 && space == 1) {
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ih = CK_SLIST_FIRST(&ie->ie_handlers);
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missed = strlen(ie->ie_fullname) + strlen(ih->ih_name) + 2 -
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sizeof(ie->ie_fullname);
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strcat(ie->ie_fullname, (missed == 0) ? " " : "-");
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strcat(ie->ie_fullname, &ih->ih_name[missed]);
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missed = 0;
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}
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last = &ie->ie_fullname[sizeof(ie->ie_fullname) - 2];
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while (missed-- > 0) {
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if (strlen(ie->ie_fullname) + 1 == sizeof(ie->ie_fullname)) {
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if (*last == '+') {
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*last = '*';
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break;
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} else
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*last = '+';
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} else if (space) {
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strcat(ie->ie_fullname, " +");
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space = 0;
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} else
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strcat(ie->ie_fullname, "+");
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}
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/*
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* If this event has an ithread, update it's priority and
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* name.
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*/
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if (ie->ie_thread != NULL)
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ithread_update(ie->ie_thread);
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CTR2(KTR_INTR, "%s: updated %s", __func__, ie->ie_fullname);
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}
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int
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intr_event_create(struct intr_event **event, void *source, int flags, int irq,
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void (*pre_ithread)(void *), void (*post_ithread)(void *),
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void (*post_filter)(void *), int (*assign_cpu)(void *, int),
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const char *fmt, ...)
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{
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struct intr_event *ie;
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va_list ap;
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/* The only valid flag during creation is IE_SOFT. */
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if ((flags & ~IE_SOFT) != 0)
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return (EINVAL);
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ie = malloc(sizeof(struct intr_event), M_ITHREAD, M_WAITOK | M_ZERO);
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ie->ie_source = source;
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ie->ie_pre_ithread = pre_ithread;
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ie->ie_post_ithread = post_ithread;
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ie->ie_post_filter = post_filter;
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ie->ie_assign_cpu = assign_cpu;
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ie->ie_flags = flags;
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ie->ie_irq = irq;
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ie->ie_cpu = NOCPU;
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CK_SLIST_INIT(&ie->ie_handlers);
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mtx_init(&ie->ie_lock, "intr event", NULL, MTX_DEF);
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va_start(ap, fmt);
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vsnprintf(ie->ie_name, sizeof(ie->ie_name), fmt, ap);
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va_end(ap);
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strlcpy(ie->ie_fullname, ie->ie_name, sizeof(ie->ie_fullname));
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mtx_lock(&event_lock);
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TAILQ_INSERT_TAIL(&event_list, ie, ie_list);
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mtx_unlock(&event_lock);
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if (event != NULL)
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*event = ie;
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CTR2(KTR_INTR, "%s: created %s", __func__, ie->ie_name);
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return (0);
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}
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/*
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* Bind an interrupt event to the specified CPU. Note that not all
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* platforms support binding an interrupt to a CPU. For those
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* platforms this request will fail. Using a cpu id of NOCPU unbinds
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* the interrupt event.
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*/
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static int
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_intr_event_bind(struct intr_event *ie, int cpu, bool bindirq, bool bindithread)
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{
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lwpid_t id;
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int error;
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/* Need a CPU to bind to. */
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if (cpu != NOCPU && CPU_ABSENT(cpu))
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return (EINVAL);
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if (ie->ie_assign_cpu == NULL)
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return (EOPNOTSUPP);
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error = priv_check(curthread, PRIV_SCHED_CPUSET_INTR);
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if (error)
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return (error);
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/*
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* If we have any ithreads try to set their mask first to verify
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* permissions, etc.
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*/
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if (bindithread) {
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mtx_lock(&ie->ie_lock);
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if (ie->ie_thread != NULL) {
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id = ie->ie_thread->it_thread->td_tid;
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mtx_unlock(&ie->ie_lock);
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error = cpuset_setithread(id, cpu);
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if (error)
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return (error);
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} else
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mtx_unlock(&ie->ie_lock);
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}
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if (bindirq)
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error = ie->ie_assign_cpu(ie->ie_source, cpu);
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if (error) {
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if (bindithread) {
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mtx_lock(&ie->ie_lock);
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if (ie->ie_thread != NULL) {
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cpu = ie->ie_cpu;
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id = ie->ie_thread->it_thread->td_tid;
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mtx_unlock(&ie->ie_lock);
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(void)cpuset_setithread(id, cpu);
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} else
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mtx_unlock(&ie->ie_lock);
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}
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return (error);
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}
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if (bindirq) {
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mtx_lock(&ie->ie_lock);
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ie->ie_cpu = cpu;
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mtx_unlock(&ie->ie_lock);
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}
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return (error);
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}
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/*
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* Bind an interrupt event to the specified CPU. For supported platforms, any
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* associated ithreads as well as the primary interrupt context will be bound
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* to the specificed CPU.
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*/
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int
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intr_event_bind(struct intr_event *ie, int cpu)
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{
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return (_intr_event_bind(ie, cpu, true, true));
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}
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/*
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* Bind an interrupt event to the specified CPU, but do not bind associated
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* ithreads.
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*/
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int
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intr_event_bind_irqonly(struct intr_event *ie, int cpu)
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{
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return (_intr_event_bind(ie, cpu, true, false));
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}
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/*
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* Bind an interrupt event's ithread to the specified CPU.
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*/
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int
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intr_event_bind_ithread(struct intr_event *ie, int cpu)
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{
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return (_intr_event_bind(ie, cpu, false, true));
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}
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/*
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* Bind an interrupt event's ithread to the specified cpuset.
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*/
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int
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intr_event_bind_ithread_cpuset(struct intr_event *ie, cpuset_t *cs)
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{
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lwpid_t id;
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mtx_lock(&ie->ie_lock);
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if (ie->ie_thread != NULL) {
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id = ie->ie_thread->it_thread->td_tid;
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mtx_unlock(&ie->ie_lock);
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return (cpuset_setthread(id, cs));
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} else {
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mtx_unlock(&ie->ie_lock);
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}
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return (ENODEV);
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}
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static struct intr_event *
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intr_lookup(int irq)
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{
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struct intr_event *ie;
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mtx_lock(&event_lock);
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TAILQ_FOREACH(ie, &event_list, ie_list)
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if (ie->ie_irq == irq &&
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(ie->ie_flags & IE_SOFT) == 0 &&
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CK_SLIST_FIRST(&ie->ie_handlers) != NULL)
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break;
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mtx_unlock(&event_lock);
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return (ie);
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}
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int
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intr_setaffinity(int irq, int mode, void *m)
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{
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struct intr_event *ie;
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cpuset_t *mask;
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int cpu, n;
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mask = m;
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cpu = NOCPU;
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/*
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* If we're setting all cpus we can unbind. Otherwise make sure
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* only one cpu is in the set.
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*/
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if (CPU_CMP(cpuset_root, mask)) {
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for (n = 0; n < CPU_SETSIZE; n++) {
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if (!CPU_ISSET(n, mask))
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continue;
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if (cpu != NOCPU)
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return (EINVAL);
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cpu = n;
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}
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}
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ie = intr_lookup(irq);
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if (ie == NULL)
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return (ESRCH);
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switch (mode) {
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case CPU_WHICH_IRQ:
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return (intr_event_bind(ie, cpu));
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case CPU_WHICH_INTRHANDLER:
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return (intr_event_bind_irqonly(ie, cpu));
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case CPU_WHICH_ITHREAD:
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return (intr_event_bind_ithread(ie, cpu));
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default:
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return (EINVAL);
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}
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}
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int
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intr_getaffinity(int irq, int mode, void *m)
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{
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struct intr_event *ie;
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struct thread *td;
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struct proc *p;
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cpuset_t *mask;
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lwpid_t id;
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int error;
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mask = m;
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ie = intr_lookup(irq);
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if (ie == NULL)
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return (ESRCH);
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error = 0;
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CPU_ZERO(mask);
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switch (mode) {
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case CPU_WHICH_IRQ:
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case CPU_WHICH_INTRHANDLER:
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mtx_lock(&ie->ie_lock);
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if (ie->ie_cpu == NOCPU)
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CPU_COPY(cpuset_root, mask);
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else
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CPU_SET(ie->ie_cpu, mask);
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mtx_unlock(&ie->ie_lock);
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break;
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case CPU_WHICH_ITHREAD:
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mtx_lock(&ie->ie_lock);
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if (ie->ie_thread == NULL) {
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mtx_unlock(&ie->ie_lock);
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CPU_COPY(cpuset_root, mask);
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} else {
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id = ie->ie_thread->it_thread->td_tid;
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mtx_unlock(&ie->ie_lock);
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error = cpuset_which(CPU_WHICH_TID, id, &p, &td, NULL);
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if (error != 0)
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return (error);
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CPU_COPY(&td->td_cpuset->cs_mask, mask);
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PROC_UNLOCK(p);
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}
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default:
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return (EINVAL);
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}
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return (0);
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}
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|
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int
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intr_event_destroy(struct intr_event *ie)
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{
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|
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mtx_lock(&event_lock);
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mtx_lock(&ie->ie_lock);
|
|
if (!CK_SLIST_EMPTY(&ie->ie_handlers)) {
|
|
mtx_unlock(&ie->ie_lock);
|
|
mtx_unlock(&event_lock);
|
|
return (EBUSY);
|
|
}
|
|
TAILQ_REMOVE(&event_list, ie, ie_list);
|
|
#ifndef notyet
|
|
if (ie->ie_thread != NULL) {
|
|
ithread_destroy(ie->ie_thread);
|
|
ie->ie_thread = NULL;
|
|
}
|
|
#endif
|
|
mtx_unlock(&ie->ie_lock);
|
|
mtx_unlock(&event_lock);
|
|
mtx_destroy(&ie->ie_lock);
|
|
free(ie, M_ITHREAD);
|
|
return (0);
|
|
}
|
|
|
|
static struct intr_thread *
|
|
ithread_create(const char *name)
|
|
{
|
|
struct intr_thread *ithd;
|
|
struct thread *td;
|
|
int error;
|
|
|
|
ithd = malloc(sizeof(struct intr_thread), M_ITHREAD, M_WAITOK | M_ZERO);
|
|
|
|
error = kproc_kthread_add(ithread_loop, ithd, &intrproc,
|
|
&td, RFSTOPPED | RFHIGHPID,
|
|
0, "intr", "%s", name);
|
|
if (error)
|
|
panic("kproc_create() failed with %d", error);
|
|
thread_lock(td);
|
|
sched_class(td, PRI_ITHD);
|
|
TD_SET_IWAIT(td);
|
|
thread_unlock(td);
|
|
td->td_pflags |= TDP_ITHREAD;
|
|
ithd->it_thread = td;
|
|
CTR2(KTR_INTR, "%s: created %s", __func__, name);
|
|
return (ithd);
|
|
}
|
|
|
|
static void
|
|
ithread_destroy(struct intr_thread *ithread)
|
|
{
|
|
struct thread *td;
|
|
|
|
CTR2(KTR_INTR, "%s: killing %s", __func__, ithread->it_event->ie_name);
|
|
td = ithread->it_thread;
|
|
thread_lock(td);
|
|
ithread->it_flags |= IT_DEAD;
|
|
if (TD_AWAITING_INTR(td)) {
|
|
TD_CLR_IWAIT(td);
|
|
sched_add(td, SRQ_INTR);
|
|
} else
|
|
thread_unlock(td);
|
|
}
|
|
|
|
int
|
|
intr_event_add_handler(struct intr_event *ie, const char *name,
|
|
driver_filter_t filter, driver_intr_t handler, void *arg, u_char pri,
|
|
enum intr_type flags, void **cookiep)
|
|
{
|
|
struct intr_handler *ih, *temp_ih;
|
|
struct intr_handler **prevptr;
|
|
struct intr_thread *it;
|
|
|
|
if (ie == NULL || name == NULL || (handler == NULL && filter == NULL))
|
|
return (EINVAL);
|
|
|
|
/* Allocate and populate an interrupt handler structure. */
|
|
ih = malloc(sizeof(struct intr_handler), M_ITHREAD, M_WAITOK | M_ZERO);
|
|
ih->ih_filter = filter;
|
|
ih->ih_handler = handler;
|
|
ih->ih_argument = arg;
|
|
strlcpy(ih->ih_name, name, sizeof(ih->ih_name));
|
|
ih->ih_event = ie;
|
|
ih->ih_pri = pri;
|
|
if (flags & INTR_EXCL)
|
|
ih->ih_flags = IH_EXCLUSIVE;
|
|
if (flags & INTR_MPSAFE)
|
|
ih->ih_flags |= IH_MPSAFE;
|
|
if (flags & INTR_ENTROPY)
|
|
ih->ih_flags |= IH_ENTROPY;
|
|
if (flags & INTR_TYPE_NET)
|
|
ih->ih_flags |= IH_NET;
|
|
|
|
/* We can only have one exclusive handler in a event. */
|
|
mtx_lock(&ie->ie_lock);
|
|
if (!CK_SLIST_EMPTY(&ie->ie_handlers)) {
|
|
if ((flags & INTR_EXCL) ||
|
|
(CK_SLIST_FIRST(&ie->ie_handlers)->ih_flags & IH_EXCLUSIVE)) {
|
|
mtx_unlock(&ie->ie_lock);
|
|
free(ih, M_ITHREAD);
|
|
return (EINVAL);
|
|
}
|
|
}
|
|
|
|
/* Create a thread if we need one. */
|
|
while (ie->ie_thread == NULL && handler != NULL) {
|
|
if (ie->ie_flags & IE_ADDING_THREAD)
|
|
msleep(ie, &ie->ie_lock, 0, "ithread", 0);
|
|
else {
|
|
ie->ie_flags |= IE_ADDING_THREAD;
|
|
mtx_unlock(&ie->ie_lock);
|
|
it = ithread_create("intr: newborn");
|
|
mtx_lock(&ie->ie_lock);
|
|
ie->ie_flags &= ~IE_ADDING_THREAD;
|
|
ie->ie_thread = it;
|
|
it->it_event = ie;
|
|
ithread_update(it);
|
|
wakeup(ie);
|
|
}
|
|
}
|
|
|
|
/* Add the new handler to the event in priority order. */
|
|
CK_SLIST_FOREACH_PREVPTR(temp_ih, prevptr, &ie->ie_handlers, ih_next) {
|
|
if (temp_ih->ih_pri > ih->ih_pri)
|
|
break;
|
|
}
|
|
CK_SLIST_INSERT_PREVPTR(prevptr, temp_ih, ih, ih_next);
|
|
|
|
intr_event_update(ie);
|
|
|
|
CTR3(KTR_INTR, "%s: added %s to %s", __func__, ih->ih_name,
|
|
ie->ie_name);
|
|
mtx_unlock(&ie->ie_lock);
|
|
|
|
if (cookiep != NULL)
|
|
*cookiep = ih;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Append a description preceded by a ':' to the name of the specified
|
|
* interrupt handler.
|
|
*/
|
|
int
|
|
intr_event_describe_handler(struct intr_event *ie, void *cookie,
|
|
const char *descr)
|
|
{
|
|
struct intr_handler *ih;
|
|
size_t space;
|
|
char *start;
|
|
|
|
mtx_lock(&ie->ie_lock);
|
|
#ifdef INVARIANTS
|
|
CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) {
|
|
if (ih == cookie)
|
|
break;
|
|
}
|
|
if (ih == NULL) {
|
|
mtx_unlock(&ie->ie_lock);
|
|
panic("handler %p not found in interrupt event %p", cookie, ie);
|
|
}
|
|
#endif
|
|
ih = cookie;
|
|
|
|
/*
|
|
* Look for an existing description by checking for an
|
|
* existing ":". This assumes device names do not include
|
|
* colons. If one is found, prepare to insert the new
|
|
* description at that point. If one is not found, find the
|
|
* end of the name to use as the insertion point.
|
|
*/
|
|
start = strchr(ih->ih_name, ':');
|
|
if (start == NULL)
|
|
start = strchr(ih->ih_name, 0);
|
|
|
|
/*
|
|
* See if there is enough remaining room in the string for the
|
|
* description + ":". The "- 1" leaves room for the trailing
|
|
* '\0'. The "+ 1" accounts for the colon.
|
|
*/
|
|
space = sizeof(ih->ih_name) - (start - ih->ih_name) - 1;
|
|
if (strlen(descr) + 1 > space) {
|
|
mtx_unlock(&ie->ie_lock);
|
|
return (ENOSPC);
|
|
}
|
|
|
|
/* Append a colon followed by the description. */
|
|
*start = ':';
|
|
strcpy(start + 1, descr);
|
|
intr_event_update(ie);
|
|
mtx_unlock(&ie->ie_lock);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Return the ie_source field from the intr_event an intr_handler is
|
|
* associated with.
|
|
*/
|
|
void *
|
|
intr_handler_source(void *cookie)
|
|
{
|
|
struct intr_handler *ih;
|
|
struct intr_event *ie;
|
|
|
|
ih = (struct intr_handler *)cookie;
|
|
if (ih == NULL)
|
|
return (NULL);
|
|
ie = ih->ih_event;
|
|
KASSERT(ie != NULL,
|
|
("interrupt handler \"%s\" has a NULL interrupt event",
|
|
ih->ih_name));
|
|
return (ie->ie_source);
|
|
}
|
|
|
|
/*
|
|
* If intr_event_handle() is running in the ISR context at the time of the call,
|
|
* then wait for it to complete.
|
|
*/
|
|
static void
|
|
intr_event_barrier(struct intr_event *ie)
|
|
{
|
|
int phase;
|
|
|
|
mtx_assert(&ie->ie_lock, MA_OWNED);
|
|
phase = ie->ie_phase;
|
|
|
|
/*
|
|
* Switch phase to direct future interrupts to the other active counter.
|
|
* Make sure that any preceding stores are visible before the switch.
|
|
*/
|
|
KASSERT(ie->ie_active[!phase] == 0, ("idle phase has activity"));
|
|
atomic_store_rel_int(&ie->ie_phase, !phase);
|
|
|
|
/*
|
|
* This code cooperates with wait-free iteration of ie_handlers
|
|
* in intr_event_handle.
|
|
* Make sure that the removal and the phase update are not reordered
|
|
* with the active count check.
|
|
* Note that no combination of acquire and release fences can provide
|
|
* that guarantee as Store->Load sequences can always be reordered.
|
|
*/
|
|
atomic_thread_fence_seq_cst();
|
|
|
|
/*
|
|
* Now wait on the inactive phase.
|
|
* The acquire fence is needed so that that all post-barrier accesses
|
|
* are after the check.
|
|
*/
|
|
while (ie->ie_active[phase] > 0)
|
|
cpu_spinwait();
|
|
atomic_thread_fence_acq();
|
|
}
|
|
|
|
static void
|
|
intr_handler_barrier(struct intr_handler *handler)
|
|
{
|
|
struct intr_event *ie;
|
|
|
|
ie = handler->ih_event;
|
|
mtx_assert(&ie->ie_lock, MA_OWNED);
|
|
KASSERT((handler->ih_flags & IH_DEAD) == 0,
|
|
("update for a removed handler"));
|
|
|
|
if (ie->ie_thread == NULL) {
|
|
intr_event_barrier(ie);
|
|
return;
|
|
}
|
|
if ((handler->ih_flags & IH_CHANGED) == 0) {
|
|
handler->ih_flags |= IH_CHANGED;
|
|
intr_event_schedule_thread(ie);
|
|
}
|
|
while ((handler->ih_flags & IH_CHANGED) != 0)
|
|
msleep(handler, &ie->ie_lock, 0, "ih_barr", 0);
|
|
}
|
|
|
|
/*
|
|
* Sleep until an ithread finishes executing an interrupt handler.
|
|
*
|
|
* XXX Doesn't currently handle interrupt filters or fast interrupt
|
|
* handlers. This is intended for LinuxKPI drivers only.
|
|
* Do not use in BSD code.
|
|
*/
|
|
void
|
|
_intr_drain(int irq)
|
|
{
|
|
struct intr_event *ie;
|
|
struct intr_thread *ithd;
|
|
struct thread *td;
|
|
|
|
ie = intr_lookup(irq);
|
|
if (ie == NULL)
|
|
return;
|
|
if (ie->ie_thread == NULL)
|
|
return;
|
|
ithd = ie->ie_thread;
|
|
td = ithd->it_thread;
|
|
/*
|
|
* We set the flag and wait for it to be cleared to avoid
|
|
* long delays with potentially busy interrupt handlers
|
|
* were we to only sample TD_AWAITING_INTR() every tick.
|
|
*/
|
|
thread_lock(td);
|
|
if (!TD_AWAITING_INTR(td)) {
|
|
ithd->it_flags |= IT_WAIT;
|
|
while (ithd->it_flags & IT_WAIT) {
|
|
thread_unlock(td);
|
|
pause("idrain", 1);
|
|
thread_lock(td);
|
|
}
|
|
}
|
|
thread_unlock(td);
|
|
return;
|
|
}
|
|
|
|
int
|
|
intr_event_remove_handler(void *cookie)
|
|
{
|
|
struct intr_handler *handler = (struct intr_handler *)cookie;
|
|
struct intr_event *ie;
|
|
struct intr_handler *ih;
|
|
struct intr_handler **prevptr;
|
|
#ifdef notyet
|
|
int dead;
|
|
#endif
|
|
|
|
if (handler == NULL)
|
|
return (EINVAL);
|
|
ie = handler->ih_event;
|
|
KASSERT(ie != NULL,
|
|
("interrupt handler \"%s\" has a NULL interrupt event",
|
|
handler->ih_name));
|
|
|
|
mtx_lock(&ie->ie_lock);
|
|
CTR3(KTR_INTR, "%s: removing %s from %s", __func__, handler->ih_name,
|
|
ie->ie_name);
|
|
CK_SLIST_FOREACH_PREVPTR(ih, prevptr, &ie->ie_handlers, ih_next) {
|
|
if (ih == handler)
|
|
break;
|
|
}
|
|
if (ih == NULL) {
|
|
panic("interrupt handler \"%s\" not found in "
|
|
"interrupt event \"%s\"", handler->ih_name, ie->ie_name);
|
|
}
|
|
|
|
/*
|
|
* If there is no ithread, then directly remove the handler. Note that
|
|
* intr_event_handle() iterates ie_handlers in a lock-less fashion, so
|
|
* care needs to be taken to keep ie_handlers consistent and to free
|
|
* the removed handler only when ie_handlers is quiescent.
|
|
*/
|
|
if (ie->ie_thread == NULL) {
|
|
CK_SLIST_REMOVE_PREVPTR(prevptr, ih, ih_next);
|
|
intr_event_barrier(ie);
|
|
intr_event_update(ie);
|
|
mtx_unlock(&ie->ie_lock);
|
|
free(handler, M_ITHREAD);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Let the interrupt thread do the job.
|
|
* The interrupt source is disabled when the interrupt thread is
|
|
* running, so it does not have to worry about interaction with
|
|
* intr_event_handle().
|
|
*/
|
|
KASSERT((handler->ih_flags & IH_DEAD) == 0,
|
|
("duplicate handle remove"));
|
|
handler->ih_flags |= IH_DEAD;
|
|
intr_event_schedule_thread(ie);
|
|
while (handler->ih_flags & IH_DEAD)
|
|
msleep(handler, &ie->ie_lock, 0, "iev_rmh", 0);
|
|
intr_event_update(ie);
|
|
|
|
#ifdef notyet
|
|
/*
|
|
* XXX: This could be bad in the case of ppbus(8). Also, I think
|
|
* this could lead to races of stale data when servicing an
|
|
* interrupt.
|
|
*/
|
|
dead = 1;
|
|
CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) {
|
|
if (ih->ih_handler != NULL) {
|
|
dead = 0;
|
|
break;
|
|
}
|
|
}
|
|
if (dead) {
|
|
ithread_destroy(ie->ie_thread);
|
|
ie->ie_thread = NULL;
|
|
}
|
|
#endif
|
|
mtx_unlock(&ie->ie_lock);
|
|
free(handler, M_ITHREAD);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
intr_event_suspend_handler(void *cookie)
|
|
{
|
|
struct intr_handler *handler = (struct intr_handler *)cookie;
|
|
struct intr_event *ie;
|
|
|
|
if (handler == NULL)
|
|
return (EINVAL);
|
|
ie = handler->ih_event;
|
|
KASSERT(ie != NULL,
|
|
("interrupt handler \"%s\" has a NULL interrupt event",
|
|
handler->ih_name));
|
|
mtx_lock(&ie->ie_lock);
|
|
handler->ih_flags |= IH_SUSP;
|
|
intr_handler_barrier(handler);
|
|
mtx_unlock(&ie->ie_lock);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
intr_event_resume_handler(void *cookie)
|
|
{
|
|
struct intr_handler *handler = (struct intr_handler *)cookie;
|
|
struct intr_event *ie;
|
|
|
|
if (handler == NULL)
|
|
return (EINVAL);
|
|
ie = handler->ih_event;
|
|
KASSERT(ie != NULL,
|
|
("interrupt handler \"%s\" has a NULL interrupt event",
|
|
handler->ih_name));
|
|
|
|
/*
|
|
* intr_handler_barrier() acts not only as a barrier,
|
|
* it also allows to check for any pending interrupts.
|
|
*/
|
|
mtx_lock(&ie->ie_lock);
|
|
handler->ih_flags &= ~IH_SUSP;
|
|
intr_handler_barrier(handler);
|
|
mtx_unlock(&ie->ie_lock);
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
intr_event_schedule_thread(struct intr_event *ie)
|
|
{
|
|
struct intr_entropy entropy;
|
|
struct intr_thread *it;
|
|
struct thread *td;
|
|
struct thread *ctd;
|
|
|
|
/*
|
|
* If no ithread or no handlers, then we have a stray interrupt.
|
|
*/
|
|
if (ie == NULL || CK_SLIST_EMPTY(&ie->ie_handlers) ||
|
|
ie->ie_thread == NULL)
|
|
return (EINVAL);
|
|
|
|
ctd = curthread;
|
|
it = ie->ie_thread;
|
|
td = it->it_thread;
|
|
|
|
/*
|
|
* If any of the handlers for this ithread claim to be good
|
|
* sources of entropy, then gather some.
|
|
*/
|
|
if (ie->ie_hflags & IH_ENTROPY) {
|
|
entropy.event = (uintptr_t)ie;
|
|
entropy.td = ctd;
|
|
random_harvest_queue(&entropy, sizeof(entropy), RANDOM_INTERRUPT);
|
|
}
|
|
|
|
KASSERT(td->td_proc != NULL, ("ithread %s has no process", ie->ie_name));
|
|
|
|
/*
|
|
* Set it_need to tell the thread to keep running if it is already
|
|
* running. Then, lock the thread and see if we actually need to
|
|
* put it on the runqueue.
|
|
*
|
|
* Use store_rel to arrange that the store to ih_need in
|
|
* swi_sched() is before the store to it_need and prepare for
|
|
* transfer of this order to loads in the ithread.
|
|
*/
|
|
atomic_store_rel_int(&it->it_need, 1);
|
|
thread_lock(td);
|
|
if (TD_AWAITING_INTR(td)) {
|
|
CTR3(KTR_INTR, "%s: schedule pid %d (%s)", __func__, td->td_proc->p_pid,
|
|
td->td_name);
|
|
TD_CLR_IWAIT(td);
|
|
sched_add(td, SRQ_INTR);
|
|
} else {
|
|
CTR5(KTR_INTR, "%s: pid %d (%s): it_need %d, state %d",
|
|
__func__, td->td_proc->p_pid, td->td_name, it->it_need, TD_GET_STATE(td));
|
|
thread_unlock(td);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Allow interrupt event binding for software interrupt handlers -- a no-op,
|
|
* since interrupts are generated in software rather than being directed by
|
|
* a PIC.
|
|
*/
|
|
static int
|
|
swi_assign_cpu(void *arg, int cpu)
|
|
{
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Add a software interrupt handler to a specified event. If a given event
|
|
* is not specified, then a new event is created.
|
|
*/
|
|
int
|
|
swi_add(struct intr_event **eventp, const char *name, driver_intr_t handler,
|
|
void *arg, int pri, enum intr_type flags, void **cookiep)
|
|
{
|
|
struct intr_event *ie;
|
|
int error = 0;
|
|
|
|
if (flags & INTR_ENTROPY)
|
|
return (EINVAL);
|
|
|
|
ie = (eventp != NULL) ? *eventp : NULL;
|
|
|
|
if (ie != NULL) {
|
|
if (!(ie->ie_flags & IE_SOFT))
|
|
return (EINVAL);
|
|
} else {
|
|
error = intr_event_create(&ie, NULL, IE_SOFT, 0,
|
|
NULL, NULL, NULL, swi_assign_cpu, "swi%d:", pri);
|
|
if (error)
|
|
return (error);
|
|
if (eventp != NULL)
|
|
*eventp = ie;
|
|
}
|
|
if (handler != NULL) {
|
|
error = intr_event_add_handler(ie, name, NULL, handler, arg,
|
|
PI_SWI(pri), flags, cookiep);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Schedule a software interrupt thread.
|
|
*/
|
|
void
|
|
swi_sched(void *cookie, int flags)
|
|
{
|
|
struct intr_handler *ih = (struct intr_handler *)cookie;
|
|
struct intr_event *ie = ih->ih_event;
|
|
struct intr_entropy entropy;
|
|
int error __unused;
|
|
|
|
CTR3(KTR_INTR, "swi_sched: %s %s need=%d", ie->ie_name, ih->ih_name,
|
|
ih->ih_need);
|
|
|
|
if ((flags & SWI_FROMNMI) == 0) {
|
|
entropy.event = (uintptr_t)ih;
|
|
entropy.td = curthread;
|
|
random_harvest_queue(&entropy, sizeof(entropy), RANDOM_SWI);
|
|
}
|
|
|
|
/*
|
|
* Set ih_need for this handler so that if the ithread is already
|
|
* running it will execute this handler on the next pass. Otherwise,
|
|
* it will execute it the next time it runs.
|
|
*/
|
|
ih->ih_need = 1;
|
|
|
|
if (flags & SWI_DELAY)
|
|
return;
|
|
|
|
if (flags & SWI_FROMNMI) {
|
|
#if defined(SMP) && (defined(__i386__) || defined(__amd64__))
|
|
KASSERT(ie == clk_intr_event,
|
|
("SWI_FROMNMI used not with clk_intr_event"));
|
|
ipi_self_from_nmi(IPI_SWI);
|
|
#endif
|
|
} else {
|
|
VM_CNT_INC(v_soft);
|
|
error = intr_event_schedule_thread(ie);
|
|
KASSERT(error == 0, ("stray software interrupt"));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Remove a software interrupt handler. Currently this code does not
|
|
* remove the associated interrupt event if it becomes empty. Calling code
|
|
* may do so manually via intr_event_destroy(), but that's not really
|
|
* an optimal interface.
|
|
*/
|
|
int
|
|
swi_remove(void *cookie)
|
|
{
|
|
|
|
return (intr_event_remove_handler(cookie));
|
|
}
|
|
|
|
static void
|
|
intr_event_execute_handlers(struct proc *p, struct intr_event *ie)
|
|
{
|
|
struct intr_handler *ih, *ihn, *ihp;
|
|
|
|
ihp = NULL;
|
|
CK_SLIST_FOREACH_SAFE(ih, &ie->ie_handlers, ih_next, ihn) {
|
|
/*
|
|
* If this handler is marked for death, remove it from
|
|
* the list of handlers and wake up the sleeper.
|
|
*/
|
|
if (ih->ih_flags & IH_DEAD) {
|
|
mtx_lock(&ie->ie_lock);
|
|
if (ihp == NULL)
|
|
CK_SLIST_REMOVE_HEAD(&ie->ie_handlers, ih_next);
|
|
else
|
|
CK_SLIST_REMOVE_AFTER(ihp, ih_next);
|
|
ih->ih_flags &= ~IH_DEAD;
|
|
wakeup(ih);
|
|
mtx_unlock(&ie->ie_lock);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Now that we know that the current element won't be removed
|
|
* update the previous element.
|
|
*/
|
|
ihp = ih;
|
|
|
|
if ((ih->ih_flags & IH_CHANGED) != 0) {
|
|
mtx_lock(&ie->ie_lock);
|
|
ih->ih_flags &= ~IH_CHANGED;
|
|
wakeup(ih);
|
|
mtx_unlock(&ie->ie_lock);
|
|
}
|
|
|
|
/* Skip filter only handlers */
|
|
if (ih->ih_handler == NULL)
|
|
continue;
|
|
|
|
/* Skip suspended handlers */
|
|
if ((ih->ih_flags & IH_SUSP) != 0)
|
|
continue;
|
|
|
|
/*
|
|
* For software interrupt threads, we only execute
|
|
* handlers that have their need flag set. Hardware
|
|
* interrupt threads always invoke all of their handlers.
|
|
*
|
|
* ih_need can only be 0 or 1. Failed cmpset below
|
|
* means that there is no request to execute handlers,
|
|
* so a retry of the cmpset is not needed.
|
|
*/
|
|
if ((ie->ie_flags & IE_SOFT) != 0 &&
|
|
atomic_cmpset_int(&ih->ih_need, 1, 0) == 0)
|
|
continue;
|
|
|
|
/* Execute this handler. */
|
|
CTR6(KTR_INTR, "%s: pid %d exec %p(%p) for %s flg=%x",
|
|
__func__, p->p_pid, (void *)ih->ih_handler,
|
|
ih->ih_argument, ih->ih_name, ih->ih_flags);
|
|
|
|
if (!(ih->ih_flags & IH_MPSAFE))
|
|
mtx_lock(&Giant);
|
|
ih->ih_handler(ih->ih_argument);
|
|
if (!(ih->ih_flags & IH_MPSAFE))
|
|
mtx_unlock(&Giant);
|
|
}
|
|
}
|
|
|
|
static void
|
|
ithread_execute_handlers(struct proc *p, struct intr_event *ie)
|
|
{
|
|
|
|
/* Interrupt handlers should not sleep. */
|
|
if (!(ie->ie_flags & IE_SOFT))
|
|
THREAD_NO_SLEEPING();
|
|
intr_event_execute_handlers(p, ie);
|
|
if (!(ie->ie_flags & IE_SOFT))
|
|
THREAD_SLEEPING_OK();
|
|
|
|
/*
|
|
* Interrupt storm handling:
|
|
*
|
|
* If this interrupt source is currently storming, then throttle
|
|
* it to only fire the handler once per clock tick.
|
|
*
|
|
* If this interrupt source is not currently storming, but the
|
|
* number of back to back interrupts exceeds the storm threshold,
|
|
* then enter storming mode.
|
|
*/
|
|
if (intr_storm_threshold != 0 && ie->ie_count >= intr_storm_threshold &&
|
|
!(ie->ie_flags & IE_SOFT)) {
|
|
/* Report the message only once every second. */
|
|
if (ppsratecheck(&ie->ie_warntm, &ie->ie_warncnt, 1)) {
|
|
printf(
|
|
"interrupt storm detected on \"%s\"; throttling interrupt source\n",
|
|
ie->ie_name);
|
|
}
|
|
pause("istorm", 1);
|
|
} else
|
|
ie->ie_count++;
|
|
|
|
/*
|
|
* Now that all the handlers have had a chance to run, reenable
|
|
* the interrupt source.
|
|
*/
|
|
if (ie->ie_post_ithread != NULL)
|
|
ie->ie_post_ithread(ie->ie_source);
|
|
}
|
|
|
|
/*
|
|
* This is the main code for interrupt threads.
|
|
*/
|
|
static void
|
|
ithread_loop(void *arg)
|
|
{
|
|
struct epoch_tracker et;
|
|
struct intr_thread *ithd;
|
|
struct intr_event *ie;
|
|
struct thread *td;
|
|
struct proc *p;
|
|
int wake, epoch_count;
|
|
bool needs_epoch;
|
|
|
|
td = curthread;
|
|
p = td->td_proc;
|
|
ithd = (struct intr_thread *)arg;
|
|
KASSERT(ithd->it_thread == td,
|
|
("%s: ithread and proc linkage out of sync", __func__));
|
|
ie = ithd->it_event;
|
|
ie->ie_count = 0;
|
|
wake = 0;
|
|
|
|
/*
|
|
* As long as we have interrupts outstanding, go through the
|
|
* list of handlers, giving each one a go at it.
|
|
*/
|
|
for (;;) {
|
|
/*
|
|
* If we are an orphaned thread, then just die.
|
|
*/
|
|
if (ithd->it_flags & IT_DEAD) {
|
|
CTR3(KTR_INTR, "%s: pid %d (%s) exiting", __func__,
|
|
p->p_pid, td->td_name);
|
|
free(ithd, M_ITHREAD);
|
|
kthread_exit();
|
|
}
|
|
|
|
/*
|
|
* Service interrupts. If another interrupt arrives while
|
|
* we are running, it will set it_need to note that we
|
|
* should make another pass.
|
|
*
|
|
* The load_acq part of the following cmpset ensures
|
|
* that the load of ih_need in ithread_execute_handlers()
|
|
* is ordered after the load of it_need here.
|
|
*/
|
|
needs_epoch =
|
|
(atomic_load_int(&ie->ie_hflags) & IH_NET) != 0;
|
|
if (needs_epoch) {
|
|
epoch_count = 0;
|
|
NET_EPOCH_ENTER(et);
|
|
}
|
|
while (atomic_cmpset_acq_int(&ithd->it_need, 1, 0) != 0) {
|
|
ithread_execute_handlers(p, ie);
|
|
if (needs_epoch &&
|
|
++epoch_count >= intr_epoch_batch) {
|
|
NET_EPOCH_EXIT(et);
|
|
epoch_count = 0;
|
|
NET_EPOCH_ENTER(et);
|
|
}
|
|
}
|
|
if (needs_epoch)
|
|
NET_EPOCH_EXIT(et);
|
|
WITNESS_WARN(WARN_PANIC, NULL, "suspending ithread");
|
|
mtx_assert(&Giant, MA_NOTOWNED);
|
|
|
|
/*
|
|
* Processed all our interrupts. Now get the sched
|
|
* lock. This may take a while and it_need may get
|
|
* set again, so we have to check it again.
|
|
*/
|
|
thread_lock(td);
|
|
if (atomic_load_acq_int(&ithd->it_need) == 0 &&
|
|
(ithd->it_flags & (IT_DEAD | IT_WAIT)) == 0) {
|
|
TD_SET_IWAIT(td);
|
|
ie->ie_count = 0;
|
|
mi_switch(SW_VOL | SWT_IWAIT);
|
|
} else {
|
|
if (ithd->it_flags & IT_WAIT) {
|
|
wake = 1;
|
|
ithd->it_flags &= ~IT_WAIT;
|
|
}
|
|
thread_unlock(td);
|
|
}
|
|
if (wake) {
|
|
wakeup(ithd);
|
|
wake = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Main interrupt handling body.
|
|
*
|
|
* Input:
|
|
* o ie: the event connected to this interrupt.
|
|
* o frame: some archs (i.e. i386) pass a frame to some.
|
|
* handlers as their main argument.
|
|
* Return value:
|
|
* o 0: everything ok.
|
|
* o EINVAL: stray interrupt.
|
|
*/
|
|
int
|
|
intr_event_handle(struct intr_event *ie, struct trapframe *frame)
|
|
{
|
|
struct intr_handler *ih;
|
|
struct trapframe *oldframe;
|
|
struct thread *td;
|
|
int phase;
|
|
int ret;
|
|
bool filter, thread;
|
|
|
|
td = curthread;
|
|
|
|
#ifdef KSTACK_USAGE_PROF
|
|
intr_prof_stack_use(td, frame);
|
|
#endif
|
|
|
|
/* An interrupt with no event or handlers is a stray interrupt. */
|
|
if (ie == NULL || CK_SLIST_EMPTY(&ie->ie_handlers))
|
|
return (EINVAL);
|
|
|
|
/*
|
|
* Execute fast interrupt handlers directly.
|
|
* To support clock handlers, if a handler registers
|
|
* with a NULL argument, then we pass it a pointer to
|
|
* a trapframe as its argument.
|
|
*/
|
|
td->td_intr_nesting_level++;
|
|
filter = false;
|
|
thread = false;
|
|
ret = 0;
|
|
critical_enter();
|
|
oldframe = td->td_intr_frame;
|
|
td->td_intr_frame = frame;
|
|
|
|
phase = ie->ie_phase;
|
|
atomic_add_int(&ie->ie_active[phase], 1);
|
|
|
|
/*
|
|
* This fence is required to ensure that no later loads are
|
|
* re-ordered before the ie_active store.
|
|
*/
|
|
atomic_thread_fence_seq_cst();
|
|
|
|
CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next) {
|
|
if ((ih->ih_flags & IH_SUSP) != 0)
|
|
continue;
|
|
if ((ie->ie_flags & IE_SOFT) != 0 && ih->ih_need == 0)
|
|
continue;
|
|
if (ih->ih_filter == NULL) {
|
|
thread = true;
|
|
continue;
|
|
}
|
|
CTR4(KTR_INTR, "%s: exec %p(%p) for %s", __func__,
|
|
ih->ih_filter, ih->ih_argument == NULL ? frame :
|
|
ih->ih_argument, ih->ih_name);
|
|
if (ih->ih_argument == NULL)
|
|
ret = ih->ih_filter(frame);
|
|
else
|
|
ret = ih->ih_filter(ih->ih_argument);
|
|
KASSERT(ret == FILTER_STRAY ||
|
|
((ret & (FILTER_SCHEDULE_THREAD | FILTER_HANDLED)) != 0 &&
|
|
(ret & ~(FILTER_SCHEDULE_THREAD | FILTER_HANDLED)) == 0),
|
|
("%s: incorrect return value %#x from %s", __func__, ret,
|
|
ih->ih_name));
|
|
filter = filter || ret == FILTER_HANDLED;
|
|
|
|
/*
|
|
* Wrapper handler special handling:
|
|
*
|
|
* in some particular cases (like pccard and pccbb),
|
|
* the _real_ device handler is wrapped in a couple of
|
|
* functions - a filter wrapper and an ithread wrapper.
|
|
* In this case (and just in this case), the filter wrapper
|
|
* could ask the system to schedule the ithread and mask
|
|
* the interrupt source if the wrapped handler is composed
|
|
* of just an ithread handler.
|
|
*
|
|
* TODO: write a generic wrapper to avoid people rolling
|
|
* their own.
|
|
*/
|
|
if (!thread) {
|
|
if (ret == FILTER_SCHEDULE_THREAD)
|
|
thread = true;
|
|
}
|
|
}
|
|
atomic_add_rel_int(&ie->ie_active[phase], -1);
|
|
|
|
td->td_intr_frame = oldframe;
|
|
|
|
if (thread) {
|
|
if (ie->ie_pre_ithread != NULL)
|
|
ie->ie_pre_ithread(ie->ie_source);
|
|
} else {
|
|
if (ie->ie_post_filter != NULL)
|
|
ie->ie_post_filter(ie->ie_source);
|
|
}
|
|
|
|
/* Schedule the ithread if needed. */
|
|
if (thread) {
|
|
int error __unused;
|
|
|
|
error = intr_event_schedule_thread(ie);
|
|
KASSERT(error == 0, ("bad stray interrupt"));
|
|
}
|
|
critical_exit();
|
|
td->td_intr_nesting_level--;
|
|
#ifdef notyet
|
|
/* The interrupt is not aknowledged by any filter and has no ithread. */
|
|
if (!thread && !filter)
|
|
return (EINVAL);
|
|
#endif
|
|
return (0);
|
|
}
|
|
|
|
#ifdef DDB
|
|
/*
|
|
* Dump details about an interrupt handler
|
|
*/
|
|
static void
|
|
db_dump_intrhand(struct intr_handler *ih)
|
|
{
|
|
int comma;
|
|
|
|
db_printf("\t%-10s ", ih->ih_name);
|
|
switch (ih->ih_pri) {
|
|
case PI_REALTIME:
|
|
db_printf("CLK ");
|
|
break;
|
|
case PI_AV:
|
|
db_printf("AV ");
|
|
break;
|
|
case PI_TTY:
|
|
db_printf("TTY ");
|
|
break;
|
|
case PI_NET:
|
|
db_printf("NET ");
|
|
break;
|
|
case PI_DISK:
|
|
db_printf("DISK");
|
|
break;
|
|
case PI_DULL:
|
|
db_printf("DULL");
|
|
break;
|
|
default:
|
|
if (ih->ih_pri >= PI_SOFT)
|
|
db_printf("SWI ");
|
|
else
|
|
db_printf("%4u", ih->ih_pri);
|
|
break;
|
|
}
|
|
db_printf(" ");
|
|
if (ih->ih_filter != NULL) {
|
|
db_printf("[F]");
|
|
db_printsym((uintptr_t)ih->ih_filter, DB_STGY_PROC);
|
|
}
|
|
if (ih->ih_handler != NULL) {
|
|
if (ih->ih_filter != NULL)
|
|
db_printf(",");
|
|
db_printf("[H]");
|
|
db_printsym((uintptr_t)ih->ih_handler, DB_STGY_PROC);
|
|
}
|
|
db_printf("(%p)", ih->ih_argument);
|
|
if (ih->ih_need ||
|
|
(ih->ih_flags & (IH_EXCLUSIVE | IH_ENTROPY | IH_DEAD |
|
|
IH_MPSAFE)) != 0) {
|
|
db_printf(" {");
|
|
comma = 0;
|
|
if (ih->ih_flags & IH_EXCLUSIVE) {
|
|
if (comma)
|
|
db_printf(", ");
|
|
db_printf("EXCL");
|
|
comma = 1;
|
|
}
|
|
if (ih->ih_flags & IH_ENTROPY) {
|
|
if (comma)
|
|
db_printf(", ");
|
|
db_printf("ENTROPY");
|
|
comma = 1;
|
|
}
|
|
if (ih->ih_flags & IH_DEAD) {
|
|
if (comma)
|
|
db_printf(", ");
|
|
db_printf("DEAD");
|
|
comma = 1;
|
|
}
|
|
if (ih->ih_flags & IH_MPSAFE) {
|
|
if (comma)
|
|
db_printf(", ");
|
|
db_printf("MPSAFE");
|
|
comma = 1;
|
|
}
|
|
if (ih->ih_need) {
|
|
if (comma)
|
|
db_printf(", ");
|
|
db_printf("NEED");
|
|
}
|
|
db_printf("}");
|
|
}
|
|
db_printf("\n");
|
|
}
|
|
|
|
/*
|
|
* Dump details about a event.
|
|
*/
|
|
void
|
|
db_dump_intr_event(struct intr_event *ie, int handlers)
|
|
{
|
|
struct intr_handler *ih;
|
|
struct intr_thread *it;
|
|
int comma;
|
|
|
|
db_printf("%s ", ie->ie_fullname);
|
|
it = ie->ie_thread;
|
|
if (it != NULL)
|
|
db_printf("(pid %d)", it->it_thread->td_proc->p_pid);
|
|
else
|
|
db_printf("(no thread)");
|
|
if ((ie->ie_flags & (IE_SOFT | IE_ADDING_THREAD)) != 0 ||
|
|
(it != NULL && it->it_need)) {
|
|
db_printf(" {");
|
|
comma = 0;
|
|
if (ie->ie_flags & IE_SOFT) {
|
|
db_printf("SOFT");
|
|
comma = 1;
|
|
}
|
|
if (ie->ie_flags & IE_ADDING_THREAD) {
|
|
if (comma)
|
|
db_printf(", ");
|
|
db_printf("ADDING_THREAD");
|
|
comma = 1;
|
|
}
|
|
if (it != NULL && it->it_need) {
|
|
if (comma)
|
|
db_printf(", ");
|
|
db_printf("NEED");
|
|
}
|
|
db_printf("}");
|
|
}
|
|
db_printf("\n");
|
|
|
|
if (handlers)
|
|
CK_SLIST_FOREACH(ih, &ie->ie_handlers, ih_next)
|
|
db_dump_intrhand(ih);
|
|
}
|
|
|
|
/*
|
|
* Dump data about interrupt handlers
|
|
*/
|
|
DB_SHOW_COMMAND(intr, db_show_intr)
|
|
{
|
|
struct intr_event *ie;
|
|
int all, verbose;
|
|
|
|
verbose = strchr(modif, 'v') != NULL;
|
|
all = strchr(modif, 'a') != NULL;
|
|
TAILQ_FOREACH(ie, &event_list, ie_list) {
|
|
if (!all && CK_SLIST_EMPTY(&ie->ie_handlers))
|
|
continue;
|
|
db_dump_intr_event(ie, verbose);
|
|
if (db_pager_quit)
|
|
break;
|
|
}
|
|
}
|
|
#endif /* DDB */
|
|
|
|
/*
|
|
* Start standard software interrupt threads
|
|
*/
|
|
static void
|
|
start_softintr(void *dummy)
|
|
{
|
|
|
|
if (swi_add(&clk_intr_event, "clk", NULL, NULL, SWI_CLOCK,
|
|
INTR_MPSAFE, NULL))
|
|
panic("died while creating clk swi ithread");
|
|
if (swi_add(NULL, "vm", swi_vm, NULL, SWI_VM, INTR_MPSAFE, &vm_ih))
|
|
panic("died while creating vm swi ithread");
|
|
}
|
|
SYSINIT(start_softintr, SI_SUB_SOFTINTR, SI_ORDER_FIRST, start_softintr,
|
|
NULL);
|
|
|
|
/*
|
|
* Sysctls used by systat and others: hw.intrnames and hw.intrcnt.
|
|
* The data for this machine dependent, and the declarations are in machine
|
|
* dependent code. The layout of intrnames and intrcnt however is machine
|
|
* independent.
|
|
*
|
|
* We do not know the length of intrcnt and intrnames at compile time, so
|
|
* calculate things at run time.
|
|
*/
|
|
static int
|
|
sysctl_intrnames(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
return (sysctl_handle_opaque(oidp, intrnames, sintrnames, req));
|
|
}
|
|
|
|
SYSCTL_PROC(_hw, OID_AUTO, intrnames,
|
|
CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, NULL, 0,
|
|
sysctl_intrnames, "",
|
|
"Interrupt Names");
|
|
|
|
static int
|
|
sysctl_intrcnt(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
#ifdef SCTL_MASK32
|
|
uint32_t *intrcnt32;
|
|
unsigned i;
|
|
int error;
|
|
|
|
if (req->flags & SCTL_MASK32) {
|
|
if (!req->oldptr)
|
|
return (sysctl_handle_opaque(oidp, NULL, sintrcnt / 2, req));
|
|
intrcnt32 = malloc(sintrcnt / 2, M_TEMP, M_NOWAIT);
|
|
if (intrcnt32 == NULL)
|
|
return (ENOMEM);
|
|
for (i = 0; i < sintrcnt / sizeof (u_long); i++)
|
|
intrcnt32[i] = intrcnt[i];
|
|
error = sysctl_handle_opaque(oidp, intrcnt32, sintrcnt / 2, req);
|
|
free(intrcnt32, M_TEMP);
|
|
return (error);
|
|
}
|
|
#endif
|
|
return (sysctl_handle_opaque(oidp, intrcnt, sintrcnt, req));
|
|
}
|
|
|
|
SYSCTL_PROC(_hw, OID_AUTO, intrcnt,
|
|
CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, NULL, 0,
|
|
sysctl_intrcnt, "",
|
|
"Interrupt Counts");
|
|
|
|
#ifdef DDB
|
|
/*
|
|
* DDB command to dump the interrupt statistics.
|
|
*/
|
|
DB_SHOW_COMMAND(intrcnt, db_show_intrcnt)
|
|
{
|
|
u_long *i;
|
|
char *cp;
|
|
u_int j;
|
|
|
|
cp = intrnames;
|
|
j = 0;
|
|
for (i = intrcnt; j < (sintrcnt / sizeof(u_long)) && !db_pager_quit;
|
|
i++, j++) {
|
|
if (*cp == '\0')
|
|
break;
|
|
if (*i != 0)
|
|
db_printf("%s\t%lu\n", cp, *i);
|
|
cp += strlen(cp) + 1;
|
|
}
|
|
}
|
|
#endif
|