/*- * Copyright (c) 2010-2013 Alexander Motin * 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, * without modification, immediately at the beginning of the file. * 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. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include "opt_timer.h" SLIST_HEAD(et_eventtimers_list, eventtimer); static struct et_eventtimers_list eventtimers = SLIST_HEAD_INITIALIZER(et_eventtimers); struct mtx et_eventtimers_mtx; MTX_SYSINIT(et_eventtimers_init, &et_eventtimers_mtx, "et_mtx", MTX_DEF); SYSCTL_NODE(_kern, OID_AUTO, eventtimer, CTLFLAG_RW, 0, "Event timers"); static SYSCTL_NODE(_kern_eventtimer, OID_AUTO, et, CTLFLAG_RW, 0, ""); /* * Register a new event timer hardware. */ int et_register(struct eventtimer *et) { struct eventtimer *tmp, *next; if (et->et_quality >= 0 || bootverbose) { if (et->et_frequency == 0) { printf("Event timer \"%s\" quality %d\n", et->et_name, et->et_quality); } else { printf("Event timer \"%s\" " "frequency %ju Hz quality %d\n", et->et_name, (uintmax_t)et->et_frequency, et->et_quality); } } KASSERT(et->et_start, ("et_register: timer has no start function")); et->et_sysctl = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_kern_eventtimer_et), OID_AUTO, et->et_name, CTLFLAG_RW, 0, "event timer description"); SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO, "flags", CTLFLAG_RD, &(et->et_flags), 0, "Event timer capabilities"); SYSCTL_ADD_UQUAD(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO, "frequency", CTLFLAG_RD, &(et->et_frequency), "Event timer base frequency"); SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO, "quality", CTLFLAG_RD, &(et->et_quality), 0, "Goodness of event timer"); ET_LOCK(); if (SLIST_EMPTY(&eventtimers) || SLIST_FIRST(&eventtimers)->et_quality < et->et_quality) { SLIST_INSERT_HEAD(&eventtimers, et, et_all); } else { SLIST_FOREACH(tmp, &eventtimers, et_all) { next = SLIST_NEXT(tmp, et_all); if (next == NULL || next->et_quality < et->et_quality) { SLIST_INSERT_AFTER(tmp, et, et_all); break; } } } ET_UNLOCK(); return (0); } /* * Deregister event timer hardware. */ int et_deregister(struct eventtimer *et) { int err = 0; if (et->et_deregister_cb != NULL) { if ((err = et->et_deregister_cb(et, et->et_arg)) != 0) return (err); } ET_LOCK(); SLIST_REMOVE(&eventtimers, et, eventtimer, et_all); ET_UNLOCK(); sysctl_remove_oid(et->et_sysctl, 1, 1); return (0); } /* * Change the frequency of the given timer. If it is the active timer, * reconfigure it on all CPUs (reschedules all current events based on the new * timer frequency). */ void et_change_frequency(struct eventtimer *et, uint64_t newfreq) { #ifndef NO_EVENTTIMERS cpu_et_frequency(et, newfreq); #endif } /* * Find free event timer hardware with specified parameters. */ struct eventtimer * et_find(const char *name, int check, int want) { struct eventtimer *et = NULL; SLIST_FOREACH(et, &eventtimers, et_all) { if (et->et_active) continue; if (name != NULL && strcasecmp(et->et_name, name) != 0) continue; if (name == NULL && et->et_quality < 0) continue; if ((et->et_flags & check) != want) continue; break; } return (et); } /* * Initialize event timer hardware. Set callbacks. */ int et_init(struct eventtimer *et, et_event_cb_t *event, et_deregister_cb_t *deregister, void *arg) { if (event == NULL) return (EINVAL); if (et->et_active) return (EBUSY); et->et_active = 1; et->et_event_cb = event; et->et_deregister_cb = deregister; et->et_arg = arg; return (0); } /* * Start event timer hardware. * first - delay before first tick. * period - period of subsequent periodic ticks. */ int et_start(struct eventtimer *et, sbintime_t first, sbintime_t period) { if (!et->et_active) return (ENXIO); KASSERT(period >= 0, ("et_start: negative period")); KASSERT((et->et_flags & ET_FLAGS_PERIODIC) || period == 0, ("et_start: period specified for oneshot-only timer")); KASSERT((et->et_flags & ET_FLAGS_ONESHOT) || period != 0, ("et_start: period not specified for periodic-only timer")); if (period != 0) { if (period < et->et_min_period) period = et->et_min_period; else if (period > et->et_max_period) period = et->et_max_period; } if (period == 0 || first != 0) { if (first < et->et_min_period) first = et->et_min_period; else if (first > et->et_max_period) first = et->et_max_period; } return (et->et_start(et, first, period)); } /* Stop event timer hardware. */ int et_stop(struct eventtimer *et) { if (!et->et_active) return (ENXIO); if (et->et_stop) return (et->et_stop(et)); return (0); } /* Mark event timer hardware as broken. */ int et_ban(struct eventtimer *et) { et->et_flags &= ~(ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT); return (0); } /* Free event timer hardware. */ int et_free(struct eventtimer *et) { if (!et->et_active) return (ENXIO); et->et_active = 0; return (0); } /* Report list of supported event timers hardware via sysctl. */ static int sysctl_kern_eventtimer_choice(SYSCTL_HANDLER_ARGS) { char buf[512], *spc; struct eventtimer *et; int error, off; spc = ""; error = 0; buf[0] = 0; off = 0; ET_LOCK(); SLIST_FOREACH(et, &eventtimers, et_all) { off += snprintf(buf + off, sizeof(buf) - off, "%s%s(%d)", spc, et->et_name, et->et_quality); spc = " "; } ET_UNLOCK(); error = SYSCTL_OUT(req, buf, strlen(buf)); return (error); } SYSCTL_PROC(_kern_eventtimer, OID_AUTO, choice, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, sysctl_kern_eventtimer_choice, "A", "Present event timers");