/*- * Copyright (c) 1996, 1997 * HD Associates, 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by HD Associates, Inc * 4. Neither the name of the author nor the names of any co-contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES 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 HD ASSOCIATES 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. */ /* ksched: Soft real time scheduling based on "rtprio". */ #include __FBSDID("$FreeBSD$"); #include "opt_posix.h" #include #include #include #include #include #include #include #include #include #include FEATURE(kposix_priority_scheduling, "POSIX P1003.1B realtime extensions"); /* ksched: Real-time extension to support POSIX priority scheduling. */ struct ksched { struct timespec rr_interval; }; int ksched_attach(struct ksched **p) { struct ksched *ksched; ksched = malloc(sizeof(*ksched), M_P31B, M_WAITOK); ksched->rr_interval.tv_sec = 0; ksched->rr_interval.tv_nsec = 1000000000L / hz * sched_rr_interval(); *p = ksched; return (0); } int ksched_detach(struct ksched *ks) { free(ks, M_P31B); return (0); } /* * XXX About priorities * * POSIX 1003.1b requires that numerically higher priorities be of * higher priority. It also permits sched_setparam to be * implementation defined for SCHED_OTHER. I don't like * the notion of inverted priorites for normal processes when * you can use "setpriority" for that. * */ /* Macros to convert between the unix (lower numerically is higher priority) * and POSIX 1003.1b (higher numerically is higher priority) */ #define p4prio_to_rtpprio(P) (RTP_PRIO_MAX - (P)) #define rtpprio_to_p4prio(P) (RTP_PRIO_MAX - (P)) #define p4prio_to_tsprio(P) ((PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE) - (P)) #define tsprio_to_p4prio(P) ((PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE) - (P)) /* These improve readability a bit for me: */ #define P1B_PRIO_MIN rtpprio_to_p4prio(RTP_PRIO_MAX) #define P1B_PRIO_MAX rtpprio_to_p4prio(RTP_PRIO_MIN) static __inline int getscheduler(struct ksched *ksched, struct thread *td, int *policy) { struct rtprio rtp; int e; e = 0; pri_to_rtp(td, &rtp); switch (rtp.type) { case RTP_PRIO_FIFO: *policy = SCHED_FIFO; break; case RTP_PRIO_REALTIME: *policy = SCHED_RR; break; default: *policy = SCHED_OTHER; break; } return (e); } int ksched_setparam(struct ksched *ksched, struct thread *td, const struct sched_param *param) { int e, policy; e = getscheduler(ksched, td, &policy); if (e == 0) e = ksched_setscheduler(ksched, td, policy, param); return (e); } int ksched_getparam(struct ksched *ksched, struct thread *td, struct sched_param *param) { struct rtprio rtp; pri_to_rtp(td, &rtp); if (RTP_PRIO_IS_REALTIME(rtp.type)) param->sched_priority = rtpprio_to_p4prio(rtp.prio); else { if (PRI_MIN_TIMESHARE < rtp.prio) /* * The interactive score has it to min realtime * so we must show max (64 most likely). */ param->sched_priority = PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE; else param->sched_priority = tsprio_to_p4prio(rtp.prio); } return (0); } /* * XXX The priority and scheduler modifications should * be moved into published interfaces in kern/kern_sync. * * The permissions to modify process p were checked in "p31b_proc()". * */ int ksched_setscheduler(struct ksched *ksched, struct thread *td, int policy, const struct sched_param *param) { struct rtprio rtp; int e; e = 0; switch(policy) { case SCHED_RR: case SCHED_FIFO: if (param->sched_priority >= P1B_PRIO_MIN && param->sched_priority <= P1B_PRIO_MAX) { rtp.prio = p4prio_to_rtpprio(param->sched_priority); rtp.type = (policy == SCHED_FIFO) ? RTP_PRIO_FIFO : RTP_PRIO_REALTIME; rtp_to_pri(&rtp, td); } else { e = EPERM; } break; case SCHED_OTHER: if (param->sched_priority >= 0 && param->sched_priority <= (PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE)) { rtp.type = RTP_PRIO_NORMAL; rtp.prio = p4prio_to_tsprio(param->sched_priority); rtp_to_pri(&rtp, td); } else { e = EINVAL; } break; default: e = EINVAL; break; } return (e); } int ksched_getscheduler(struct ksched *ksched, struct thread *td, int *policy) { return (getscheduler(ksched, td, policy)); } /* ksched_yield: Yield the CPU. */ int ksched_yield(struct ksched *ksched) { sched_relinquish(curthread); return (0); } int ksched_get_priority_max(struct ksched *ksched, int policy, int *prio) { int e; e = 0; switch (policy) { case SCHED_FIFO: case SCHED_RR: *prio = P1B_PRIO_MAX; break; case SCHED_OTHER: *prio = PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE; break; default: e = EINVAL; break; } return (e); } int ksched_get_priority_min(struct ksched *ksched, int policy, int *prio) { int e; e = 0; switch (policy) { case SCHED_FIFO: case SCHED_RR: *prio = P1B_PRIO_MIN; break; case SCHED_OTHER: *prio = 0; break; default: e = EINVAL; break; } return (e); } int ksched_rr_get_interval(struct ksched *ksched, struct thread *td, struct timespec *timespec) { *timespec = ksched->rr_interval; return (0); }