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clockintr: switch from callee- to caller-allocated clockintr structs

Currently, clockintr_establish() calls malloc(9) to allocate a
clockintr struct on behalf of the caller.  mpi@ says this behavior is
incompatible with dt(4).  In particular, calling malloc(9) during the
initialization of a PCB outside of dt_pcb_alloc() is (a) awkward and
(b) may conflict with future changes/optimizations to PCB allocation.

To side-step the problem, this patch changes the clockintr subsystem
to use caller-allocated clockintr structs instead of callee-allocated
structs.

clockintr_establish() is named after softintr_establish(), which uses
malloc(9) internally to create softintr objects.  The clockintr subsystem
is no longer using malloc(9), so the "establish" naming is no longer apt.
To avoid confusion, this patch also renames "clockintr_establish" to
"clockintr_bind".

Requested by mpi@.  Tweaked by mpi@.

Thread: https://marc.info/?l=openbsd-tech&m=170597126103504&w=2

ok claudio@ mlarkin@ mpi@

/*	$OpenBSD: sched.h,v 1.70 2024/01/24 19:23:38 cheloha Exp $	*/
/* $NetBSD: sched.h,v 1.2 1999/02/28 18:14:58 ross Exp $ */

/*-
 * Copyright (c) 1999 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Ross Harvey.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*-
 * Copyright (c) 1982, 1986, 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)kern_clock.c	8.5 (Berkeley) 1/21/94
 */

#ifndef	_SYS_SCHED_H_
#define	_SYS_SCHED_H_

/*
 * Posix defines a <sched.h> which may want to include <sys/sched.h>
 */

/*
 * CPU states.
 * XXX Not really scheduler state, but no other good place to put
 * it right now, and it really is per-CPU.
 */
#define CP_USER		0
#define CP_NICE		1
#define CP_SYS		2
#define CP_SPIN		3
#define CP_INTR		4
#define CP_IDLE		5
#define CPUSTATES	6

struct cpustats {
	uint64_t	cs_time[CPUSTATES];	/* CPU state statistics */
	uint64_t	cs_flags;		/* see below */
};

#define CPUSTATS_ONLINE		0x0001	/* CPU is schedulable */

#ifdef	_KERNEL

#include <sys/clockintr.h>
#include <sys/queue.h>

#define	SCHED_NQS	32			/* 32 run queues. */

struct smr_entry;

/*
 * Per-CPU scheduler state.
 */
struct schedstate_percpu {
	struct proc *spc_idleproc;	/* idle proc for this cpu */
	TAILQ_HEAD(prochead, proc) spc_qs[SCHED_NQS];
	LIST_HEAD(,proc) spc_deadproc;
	struct timespec spc_runtime;	/* time curproc started running */
	volatile int spc_schedflags;	/* flags; see below */
	u_int spc_schedticks;		/* ticks for schedclock() */
	u_int64_t spc_cp_time[CPUSTATES]; /* CPU state statistics */
	u_char spc_curpriority;		/* usrpri of curproc */

	struct clockintr spc_itimer;	/* [o] itimer_update handle */
	struct clockintr spc_profclock;	/* [o] profclock handle */
	struct clockintr spc_roundrobin;/* [o] roundrobin handle */
	struct clockintr spc_statclock;	/* [o] statclock handle */

	u_int spc_nrun;			/* procs on the run queues */

	volatile uint32_t spc_whichqs;
	volatile u_int spc_spinning;	/* this cpu is currently spinning */

	SIMPLEQ_HEAD(, smr_entry) spc_deferred; /* deferred smr calls */
	u_int spc_ndeferred;		/* number of deferred smr calls */
	u_int spc_smrdepth;		/* level of smr nesting */
	u_char spc_smrexpedite;		/* if set, dispatch smr entries
					 * without delay */
	u_char spc_smrgp;		/* this CPU's view of grace period */
};

/* spc_flags */
#define SPCF_SEENRR             0x0001  /* process has seen roundrobin() */
#define SPCF_SHOULDYIELD        0x0002  /* process should yield the CPU */
#define SPCF_SWITCHCLEAR        (SPCF_SEENRR|SPCF_SHOULDYIELD)
#define SPCF_SHOULDHALT		0x0004	/* CPU should be vacated */
#define SPCF_HALTED		0x0008	/* CPU has been halted */
#define SPCF_PROFCLOCK		0x0010	/* profclock() was started */
#define SPCF_ITIMER		0x0020	/* itimer_update() was started */

#define	SCHED_PPQ	(128 / SCHED_NQS)	/* priorities per queue */
#define NICE_WEIGHT 2			/* priorities per nice level */
#define	ESTCPULIM(e) min((e), NICE_WEIGHT * PRIO_MAX - SCHED_PPQ)

extern uint64_t roundrobin_period;

struct proc;
void schedclock(struct proc *);
struct clockrequest;
void roundrobin(struct clockrequest *, void *, void *);
void scheduler_start(void);
void userret(struct proc *p);

struct cpu_info;
void sched_init_cpu(struct cpu_info *);
void sched_idle(void *);
void sched_exit(struct proc *);
void sched_toidle(void);
void mi_switch(void);
void cpu_switchto(struct proc *, struct proc *);
struct proc *sched_chooseproc(void);
struct cpu_info *sched_choosecpu(struct proc *);
struct cpu_info *sched_choosecpu_fork(struct proc *parent, int);
void cpu_idle_enter(void);
void cpu_idle_cycle(void);
void cpu_idle_leave(void);
void sched_peg_curproc(struct cpu_info *ci);
void sched_barrier(struct cpu_info *ci);

int sysctl_hwsetperf(void *, size_t *, void *, size_t);
int sysctl_hwperfpolicy(void *, size_t *, void *, size_t);
int sysctl_hwsmt(void *, size_t *, void *, size_t);
int sysctl_hwncpuonline(void);

#ifdef MULTIPROCESSOR
void sched_start_secondary_cpus(void);
void sched_stop_secondary_cpus(void);
#endif

#define cpu_is_idle(ci)	((ci)->ci_schedstate.spc_whichqs == 0)
int	cpu_is_online(struct cpu_info *);

void sched_init_runqueues(void);
void setrunqueue(struct cpu_info *, struct proc *, uint8_t);
void remrunqueue(struct proc *);

/* Chargeback parents for the sins of their children.  */
#define scheduler_wait_hook(parent, child) do {				\
	(parent)->p_estcpu = ESTCPULIM((parent)->p_estcpu + (child)->p_estcpu);\
} while (0)

/* Allow other processes to progress */
#define	sched_pause(func) do {						\
	if (curcpu()->ci_schedstate.spc_schedflags & SPCF_SHOULDYIELD)	\
		func();							\
} while (0)

#if defined(MULTIPROCESSOR)
#include <sys/lock.h>

/*
 * XXX Instead of using struct lock for the kernel lock and thus requiring us
 * XXX to implement simplelocks, causing all sorts of fine-grained locks all
 * XXX over our tree to be activated, the sched_lock is a different kind of
 * XXX lock to avoid introducing locking protocol bugs.
 */
extern struct __mp_lock sched_lock;

#define	SCHED_ASSERT_LOCKED()						\
do {									\
	splassert(IPL_SCHED);						\
	KASSERT(__mp_lock_held(&sched_lock, curcpu()));			\
} while (0)
#define	SCHED_ASSERT_UNLOCKED()						\
do {									\
	KASSERT(__mp_lock_held(&sched_lock, curcpu()) == 0);		\
} while (0)

#define	SCHED_LOCK_INIT()	__mp_lock_init(&sched_lock)

#define	SCHED_LOCK(s)							\
do {									\
	s = splsched();							\
	__mp_lock(&sched_lock);						\
} while (/* CONSTCOND */ 0)

#define	SCHED_UNLOCK(s)							\
do {									\
	__mp_unlock(&sched_lock);					\
	splx(s);							\
} while (/* CONSTCOND */ 0)

#else /* ! MULTIPROCESSOR */

#define	SCHED_ASSERT_LOCKED()		splassert(IPL_SCHED);
#define	SCHED_ASSERT_UNLOCKED()		/* nothing */

#define	SCHED_LOCK_INIT()		/* nothing */

#define	SCHED_LOCK(s)			s = splsched()
#define	SCHED_UNLOCK(s)			splx(s)

#endif /* MULTIPROCESSOR */

#endif	/* _KERNEL */
#endif	/* _SYS_SCHED_H_ */