678 lines
18 KiB
C
678 lines
18 KiB
C
/*-
|
|
* Copyright (c) 1982, 1986, 1990, 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. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. 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_synch.c 8.6 (Berkeley) 1/21/94
|
|
* $Id: kern_synch.c,v 1.8 1994/10/18 06:55:39 davidg Exp $
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/signalvar.h>
|
|
#include <sys/resourcevar.h>
|
|
#include <sys/signalvar.h>
|
|
#include <vm/vm.h>
|
|
#ifdef KTRACE
|
|
#include <sys/ktrace.h>
|
|
#endif
|
|
|
|
#include <machine/cpu.h>
|
|
|
|
u_char curpriority; /* usrpri of curproc */
|
|
int lbolt; /* once a second sleep address */
|
|
|
|
/*
|
|
* Force switch among equal priority processes every 100ms.
|
|
*/
|
|
/* ARGSUSED */
|
|
void
|
|
roundrobin(arg)
|
|
void *arg;
|
|
{
|
|
|
|
need_resched();
|
|
timeout(roundrobin, NULL, hz / 10);
|
|
}
|
|
|
|
/*
|
|
* Constants for digital decay and forget:
|
|
* 90% of (p_estcpu) usage in 5 * loadav time
|
|
* 95% of (p_pctcpu) usage in 60 seconds (load insensitive)
|
|
* Note that, as ps(1) mentions, this can let percentages
|
|
* total over 100% (I've seen 137.9% for 3 processes).
|
|
*
|
|
* Note that hardclock updates p_estcpu and p_cpticks independently.
|
|
*
|
|
* We wish to decay away 90% of p_estcpu in (5 * loadavg) seconds.
|
|
* That is, the system wants to compute a value of decay such
|
|
* that the following for loop:
|
|
* for (i = 0; i < (5 * loadavg); i++)
|
|
* p_estcpu *= decay;
|
|
* will compute
|
|
* p_estcpu *= 0.1;
|
|
* for all values of loadavg:
|
|
*
|
|
* Mathematically this loop can be expressed by saying:
|
|
* decay ** (5 * loadavg) ~= .1
|
|
*
|
|
* The system computes decay as:
|
|
* decay = (2 * loadavg) / (2 * loadavg + 1)
|
|
*
|
|
* We wish to prove that the system's computation of decay
|
|
* will always fulfill the equation:
|
|
* decay ** (5 * loadavg) ~= .1
|
|
*
|
|
* If we compute b as:
|
|
* b = 2 * loadavg
|
|
* then
|
|
* decay = b / (b + 1)
|
|
*
|
|
* We now need to prove two things:
|
|
* 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1)
|
|
* 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg)
|
|
*
|
|
* Facts:
|
|
* For x close to zero, exp(x) =~ 1 + x, since
|
|
* exp(x) = 0! + x**1/1! + x**2/2! + ... .
|
|
* therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b.
|
|
* For x close to zero, ln(1+x) =~ x, since
|
|
* ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1
|
|
* therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1).
|
|
* ln(.1) =~ -2.30
|
|
*
|
|
* Proof of (1):
|
|
* Solve (factor)**(power) =~ .1 given power (5*loadav):
|
|
* solving for factor,
|
|
* ln(factor) =~ (-2.30/5*loadav), or
|
|
* factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) =
|
|
* exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED
|
|
*
|
|
* Proof of (2):
|
|
* Solve (factor)**(power) =~ .1 given factor == (b/(b+1)):
|
|
* solving for power,
|
|
* power*ln(b/(b+1)) =~ -2.30, or
|
|
* power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED
|
|
*
|
|
* Actual power values for the implemented algorithm are as follows:
|
|
* loadav: 1 2 3 4
|
|
* power: 5.68 10.32 14.94 19.55
|
|
*/
|
|
|
|
/* calculations for digital decay to forget 90% of usage in 5*loadav sec */
|
|
#define loadfactor(loadav) (2 * (loadav))
|
|
#define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE))
|
|
|
|
/* decay 95% of `p_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */
|
|
fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */
|
|
|
|
/*
|
|
* If `ccpu' is not equal to `exp(-1/20)' and you still want to use the
|
|
* faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below
|
|
* and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT).
|
|
*
|
|
* To estimate CCPU_SHIFT for exp(-1/20), the following formula was used:
|
|
* 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits).
|
|
*
|
|
* If you dont want to bother with the faster/more-accurate formula, you
|
|
* can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate
|
|
* (more general) method of calculating the %age of CPU used by a process.
|
|
*/
|
|
#define CCPU_SHIFT 11
|
|
|
|
/*
|
|
* Recompute process priorities, every hz ticks.
|
|
*/
|
|
/* ARGSUSED */
|
|
void
|
|
schedcpu(arg)
|
|
void *arg;
|
|
{
|
|
register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
|
|
register struct proc *p;
|
|
register int s;
|
|
register unsigned int newcpu;
|
|
|
|
wakeup((caddr_t)&lbolt);
|
|
for (p = (struct proc *)allproc; p != NULL; p = p->p_next) {
|
|
/*
|
|
* Increment time in/out of memory and sleep time
|
|
* (if sleeping). We ignore overflow; with 16-bit int's
|
|
* (remember them?) overflow takes 45 days.
|
|
*/
|
|
p->p_swtime++;
|
|
if (p->p_stat == SSLEEP || p->p_stat == SSTOP)
|
|
p->p_slptime++;
|
|
p->p_pctcpu = (p->p_pctcpu * ccpu) >> FSHIFT;
|
|
/*
|
|
* If the process has slept the entire second,
|
|
* stop recalculating its priority until it wakes up.
|
|
*/
|
|
if (p->p_slptime > 1)
|
|
continue;
|
|
s = splstatclock(); /* prevent state changes */
|
|
/*
|
|
* p_pctcpu is only for ps.
|
|
*/
|
|
#if (FSHIFT >= CCPU_SHIFT)
|
|
p->p_pctcpu += (hz == 100)?
|
|
((fixpt_t) p->p_cpticks) << (FSHIFT - CCPU_SHIFT):
|
|
100 * (((fixpt_t) p->p_cpticks)
|
|
<< (FSHIFT - CCPU_SHIFT)) / hz;
|
|
#else
|
|
p->p_pctcpu += ((FSCALE - ccpu) *
|
|
(p->p_cpticks * FSCALE / hz)) >> FSHIFT;
|
|
#endif
|
|
p->p_cpticks = 0;
|
|
newcpu = (u_int) decay_cpu(loadfac, p->p_estcpu) + p->p_nice;
|
|
p->p_estcpu = min(newcpu, UCHAR_MAX);
|
|
resetpriority(p);
|
|
if (p->p_priority >= PUSER) {
|
|
#define PPQ (128 / NQS) /* priorities per queue */
|
|
if ((p != curproc) &&
|
|
p->p_stat == SRUN &&
|
|
(p->p_flag & P_INMEM) &&
|
|
(p->p_priority / PPQ) != (p->p_usrpri / PPQ)) {
|
|
remrq(p);
|
|
p->p_priority = p->p_usrpri;
|
|
setrunqueue(p);
|
|
} else
|
|
p->p_priority = p->p_usrpri;
|
|
}
|
|
splx(s);
|
|
}
|
|
vmmeter();
|
|
timeout(schedcpu, (void *)0, hz);
|
|
}
|
|
|
|
/*
|
|
* Recalculate the priority of a process after it has slept for a while.
|
|
* For all load averages >= 1 and max p_estcpu of 255, sleeping for at
|
|
* least six times the loadfactor will decay p_estcpu to zero.
|
|
*/
|
|
void
|
|
updatepri(p)
|
|
register struct proc *p;
|
|
{
|
|
register unsigned int newcpu = p->p_estcpu;
|
|
register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
|
|
|
|
if (p->p_slptime > 5 * loadfac)
|
|
p->p_estcpu = 0;
|
|
else {
|
|
p->p_slptime--; /* the first time was done in schedcpu */
|
|
while (newcpu && --p->p_slptime)
|
|
newcpu = (int) decay_cpu(loadfac, newcpu);
|
|
p->p_estcpu = min(newcpu, UCHAR_MAX);
|
|
}
|
|
resetpriority(p);
|
|
}
|
|
|
|
/*
|
|
* We're only looking at 7 bits of the address; everything is
|
|
* aligned to 4, lots of things are aligned to greater powers
|
|
* of 2. Shift right by 8, i.e. drop the bottom 256 worth.
|
|
*/
|
|
#define TABLESIZE 128
|
|
#define LOOKUP(x) (((int)(x) >> 8) & (TABLESIZE - 1))
|
|
struct slpque {
|
|
struct proc *sq_head;
|
|
struct proc **sq_tailp;
|
|
} slpque[TABLESIZE];
|
|
|
|
/*
|
|
* During autoconfiguration or after a panic, a sleep will simply
|
|
* lower the priority briefly to allow interrupts, then return.
|
|
* The priority to be used (safepri) is machine-dependent, thus this
|
|
* value is initialized and maintained in the machine-dependent layers.
|
|
* This priority will typically be 0, or the lowest priority
|
|
* that is safe for use on the interrupt stack; it can be made
|
|
* higher to block network software interrupts after panics.
|
|
*/
|
|
int safepri;
|
|
|
|
/*
|
|
* General sleep call. Suspends the current process until a wakeup is
|
|
* performed on the specified identifier. The process will then be made
|
|
* runnable with the specified priority. Sleeps at most timo/hz seconds
|
|
* (0 means no timeout). If pri includes PCATCH flag, signals are checked
|
|
* before and after sleeping, else signals are not checked. Returns 0 if
|
|
* awakened, EWOULDBLOCK if the timeout expires. If PCATCH is set and a
|
|
* signal needs to be delivered, ERESTART is returned if the current system
|
|
* call should be restarted if possible, and EINTR is returned if the system
|
|
* call should be interrupted by the signal (return EINTR).
|
|
*/
|
|
int
|
|
tsleep(ident, priority, wmesg, timo)
|
|
void *ident;
|
|
int priority, timo;
|
|
char *wmesg;
|
|
{
|
|
register struct proc *p = curproc;
|
|
register struct slpque *qp;
|
|
register s;
|
|
int sig, catch = priority & PCATCH;
|
|
extern int cold;
|
|
void endtsleep __P((void *));
|
|
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(p, KTR_CSW))
|
|
ktrcsw(p->p_tracep, 1, 0);
|
|
#endif
|
|
s = splhigh();
|
|
if (cold || panicstr) {
|
|
/*
|
|
* After a panic, or during autoconfiguration,
|
|
* just give interrupts a chance, then just return;
|
|
* don't run any other procs or panic below,
|
|
* in case this is the idle process and already asleep.
|
|
*/
|
|
splx(safepri);
|
|
splx(s);
|
|
return (0);
|
|
}
|
|
#ifdef DIAGNOSTIC
|
|
if (ident == NULL || p->p_stat != SRUN || p->p_back)
|
|
panic("tsleep");
|
|
#endif
|
|
p->p_wchan = ident;
|
|
p->p_wmesg = wmesg;
|
|
p->p_slptime = 0;
|
|
p->p_priority = priority & PRIMASK;
|
|
qp = &slpque[LOOKUP(ident)];
|
|
if (qp->sq_head == 0)
|
|
qp->sq_head = p;
|
|
else
|
|
*qp->sq_tailp = p;
|
|
*(qp->sq_tailp = &p->p_forw) = 0;
|
|
if (timo)
|
|
timeout(endtsleep, (void *)p, timo);
|
|
/*
|
|
* We put ourselves on the sleep queue and start our timeout
|
|
* before calling CURSIG, as we could stop there, and a wakeup
|
|
* or a SIGCONT (or both) could occur while we were stopped.
|
|
* A SIGCONT would cause us to be marked as SSLEEP
|
|
* without resuming us, thus we must be ready for sleep
|
|
* when CURSIG is called. If the wakeup happens while we're
|
|
* stopped, p->p_wchan will be 0 upon return from CURSIG.
|
|
*/
|
|
if (catch) {
|
|
p->p_flag |= P_SINTR;
|
|
if ((sig = CURSIG(p))) {
|
|
if (p->p_wchan)
|
|
unsleep(p);
|
|
p->p_stat = SRUN;
|
|
goto resume;
|
|
}
|
|
if (p->p_wchan == 0) {
|
|
catch = 0;
|
|
goto resume;
|
|
}
|
|
} else
|
|
sig = 0;
|
|
p->p_stat = SSLEEP;
|
|
p->p_stats->p_ru.ru_nvcsw++;
|
|
mi_switch();
|
|
resume:
|
|
curpriority = p->p_usrpri;
|
|
splx(s);
|
|
p->p_flag &= ~P_SINTR;
|
|
if (p->p_flag & P_TIMEOUT) {
|
|
p->p_flag &= ~P_TIMEOUT;
|
|
if (sig == 0) {
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(p, KTR_CSW))
|
|
ktrcsw(p->p_tracep, 0, 0);
|
|
#endif
|
|
return (EWOULDBLOCK);
|
|
}
|
|
} else if (timo)
|
|
untimeout(endtsleep, (void *)p);
|
|
if (catch && (sig != 0 || (sig = CURSIG(p)))) {
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(p, KTR_CSW))
|
|
ktrcsw(p->p_tracep, 0, 0);
|
|
#endif
|
|
if (p->p_sigacts->ps_sigintr & sigmask(sig))
|
|
return (EINTR);
|
|
return (ERESTART);
|
|
}
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(p, KTR_CSW))
|
|
ktrcsw(p->p_tracep, 0, 0);
|
|
#endif
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Implement timeout for tsleep.
|
|
* If process hasn't been awakened (wchan non-zero),
|
|
* set timeout flag and undo the sleep. If proc
|
|
* is stopped, just unsleep so it will remain stopped.
|
|
*/
|
|
void
|
|
endtsleep(arg)
|
|
void *arg;
|
|
{
|
|
register struct proc *p;
|
|
int s;
|
|
|
|
p = (struct proc *)arg;
|
|
s = splhigh();
|
|
if (p->p_wchan) {
|
|
if (p->p_stat == SSLEEP)
|
|
setrunnable(p);
|
|
else
|
|
unsleep(p);
|
|
p->p_flag |= P_TIMEOUT;
|
|
}
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* Short-term, non-interruptable sleep.
|
|
*/
|
|
void
|
|
sleep(ident, priority)
|
|
void *ident;
|
|
int priority;
|
|
{
|
|
register struct proc *p = curproc;
|
|
register struct slpque *qp;
|
|
register s;
|
|
extern int cold;
|
|
|
|
#ifdef DIAGNOSTIC
|
|
if (priority > PZERO) {
|
|
printf("sleep called with priority %d > PZERO, wchan: %p\n",
|
|
priority, ident);
|
|
panic("old sleep");
|
|
}
|
|
#endif
|
|
s = splhigh();
|
|
if (cold || panicstr) {
|
|
/*
|
|
* After a panic, or during autoconfiguration,
|
|
* just give interrupts a chance, then just return;
|
|
* don't run any other procs or panic below,
|
|
* in case this is the idle process and already asleep.
|
|
*/
|
|
splx(safepri);
|
|
splx(s);
|
|
return;
|
|
}
|
|
#ifdef DIAGNOSTIC
|
|
if (ident == NULL || p->p_stat != SRUN || p->p_back)
|
|
panic("sleep");
|
|
#endif
|
|
p->p_wchan = ident;
|
|
p->p_wmesg = NULL;
|
|
p->p_slptime = 0;
|
|
p->p_priority = priority;
|
|
qp = &slpque[LOOKUP(ident)];
|
|
if (qp->sq_head == 0)
|
|
qp->sq_head = p;
|
|
else
|
|
*qp->sq_tailp = p;
|
|
*(qp->sq_tailp = &p->p_forw) = 0;
|
|
p->p_stat = SSLEEP;
|
|
p->p_stats->p_ru.ru_nvcsw++;
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(p, KTR_CSW))
|
|
ktrcsw(p->p_tracep, 1, 0);
|
|
#endif
|
|
mi_switch();
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(p, KTR_CSW))
|
|
ktrcsw(p->p_tracep, 0, 0);
|
|
#endif
|
|
curpriority = p->p_usrpri;
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* Remove a process from its wait queue
|
|
*/
|
|
void
|
|
unsleep(p)
|
|
register struct proc *p;
|
|
{
|
|
register struct slpque *qp;
|
|
register struct proc **hp;
|
|
int s;
|
|
|
|
s = splhigh();
|
|
if (p->p_wchan) {
|
|
hp = &(qp = &slpque[LOOKUP(p->p_wchan)])->sq_head;
|
|
while (*hp != p)
|
|
hp = &(*hp)->p_forw;
|
|
*hp = p->p_forw;
|
|
if (qp->sq_tailp == &p->p_forw)
|
|
qp->sq_tailp = hp;
|
|
p->p_wchan = 0;
|
|
}
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* Make all processes sleeping on the specified identifier runnable.
|
|
*/
|
|
void
|
|
wakeup(ident)
|
|
register void *ident;
|
|
{
|
|
register struct slpque *qp;
|
|
register struct proc *p, **q;
|
|
int s;
|
|
|
|
s = splhigh();
|
|
qp = &slpque[LOOKUP(ident)];
|
|
restart:
|
|
for (q = &qp->sq_head; *q; ) {
|
|
p = *q;
|
|
#ifdef DIAGNOSTIC
|
|
if (p->p_back || (p->p_stat != SSLEEP && p->p_stat != SSTOP))
|
|
panic("wakeup");
|
|
#endif
|
|
if (p->p_wchan == ident) {
|
|
p->p_wchan = 0;
|
|
*q = p->p_forw;
|
|
if (qp->sq_tailp == &p->p_forw)
|
|
qp->sq_tailp = q;
|
|
if (p->p_stat == SSLEEP) {
|
|
/* OPTIMIZED EXPANSION OF setrunnable(p); */
|
|
if (p->p_slptime > 1)
|
|
updatepri(p);
|
|
p->p_slptime = 0;
|
|
p->p_stat = SRUN;
|
|
if (p->p_flag & P_INMEM)
|
|
setrunqueue(p);
|
|
/*
|
|
* Since curpriority is a user priority,
|
|
* p->p_priority is always better than
|
|
* curpriority.
|
|
*/
|
|
if ((p->p_flag & P_INMEM) == 0)
|
|
wakeup((caddr_t)&proc0);
|
|
else
|
|
need_resched();
|
|
/* END INLINE EXPANSION */
|
|
goto restart;
|
|
}
|
|
} else
|
|
q = &p->p_forw;
|
|
}
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* The machine independent parts of mi_switch().
|
|
* Must be called at splstatclock() or higher.
|
|
*/
|
|
void
|
|
mi_switch()
|
|
{
|
|
register struct proc *p = curproc; /* XXX */
|
|
register struct rlimit *rlim;
|
|
register long s, u;
|
|
struct timeval tv;
|
|
|
|
/*
|
|
* Compute the amount of time during which the current
|
|
* process was running, and add that to its total so far.
|
|
*/
|
|
microtime(&tv);
|
|
u = p->p_rtime.tv_usec + (tv.tv_usec - runtime.tv_usec);
|
|
s = p->p_rtime.tv_sec + (tv.tv_sec - runtime.tv_sec);
|
|
if (u < 0) {
|
|
u += 1000000;
|
|
s--;
|
|
} else if (u >= 1000000) {
|
|
u -= 1000000;
|
|
s++;
|
|
}
|
|
p->p_rtime.tv_usec = u;
|
|
p->p_rtime.tv_sec = s;
|
|
|
|
/*
|
|
* Check if the process exceeds its cpu resource allocation.
|
|
* If over max, kill it. In any case, if it has run for more
|
|
* than 10 minutes, reduce priority to give others a chance.
|
|
*/
|
|
if (p->p_stat != SZOMB) {
|
|
rlim = &p->p_rlimit[RLIMIT_CPU];
|
|
if (s >= rlim->rlim_cur) {
|
|
if (s >= rlim->rlim_max)
|
|
psignal(p, SIGKILL);
|
|
else {
|
|
psignal(p, SIGXCPU);
|
|
if (rlim->rlim_cur < rlim->rlim_max)
|
|
rlim->rlim_cur += 5;
|
|
}
|
|
}
|
|
if (s > 10 * 60 && p->p_ucred->cr_uid && p->p_nice == NZERO) {
|
|
p->p_nice = NZERO + 4;
|
|
resetpriority(p);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Pick a new current process and record its start time.
|
|
*/
|
|
cnt.v_swtch++;
|
|
cpu_switch(p);
|
|
microtime(&runtime);
|
|
}
|
|
|
|
/*
|
|
* Initialize the (doubly-linked) run queues
|
|
* to be empty.
|
|
*/
|
|
void
|
|
rqinit()
|
|
{
|
|
register int i;
|
|
|
|
for (i = 0; i < NQS; i++) {
|
|
qs[i].ph_link = qs[i].ph_rlink = (struct proc *)&qs[i];
|
|
rtqs[i].ph_link = rtqs[i].ph_rlink = (struct proc *)&rtqs[i];
|
|
idqs[i].ph_link = idqs[i].ph_rlink = (struct proc *)&idqs[i];
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Change process state to be runnable,
|
|
* placing it on the run queue if it is in memory,
|
|
* and awakening the swapper if it isn't in memory.
|
|
*/
|
|
void
|
|
setrunnable(p)
|
|
register struct proc *p;
|
|
{
|
|
register int s;
|
|
|
|
s = splhigh();
|
|
switch (p->p_stat) {
|
|
case 0:
|
|
case SRUN:
|
|
case SZOMB:
|
|
default:
|
|
panic("setrunnable");
|
|
case SSTOP:
|
|
case SSLEEP:
|
|
unsleep(p); /* e.g. when sending signals */
|
|
break;
|
|
|
|
case SIDL:
|
|
break;
|
|
}
|
|
p->p_stat = SRUN;
|
|
if (p->p_flag & P_INMEM)
|
|
setrunqueue(p);
|
|
splx(s);
|
|
if (p->p_slptime > 1)
|
|
updatepri(p);
|
|
p->p_slptime = 0;
|
|
if ((p->p_flag & P_INMEM) == 0)
|
|
wakeup((caddr_t)&proc0);
|
|
else if (p->p_priority < curpriority)
|
|
need_resched();
|
|
}
|
|
|
|
/*
|
|
* Compute the priority of a process when running in user mode.
|
|
* Arrange to reschedule if the resulting priority is better
|
|
* than that of the current process.
|
|
*/
|
|
void
|
|
resetpriority(p)
|
|
register struct proc *p;
|
|
{
|
|
register unsigned int newpriority;
|
|
|
|
if (p->p_rtprio.type == RTP_PRIO_NORMAL) {
|
|
newpriority = PUSER + p->p_estcpu / 4 + 2 * p->p_nice;
|
|
newpriority = min(newpriority, MAXPRI);
|
|
p->p_usrpri = newpriority;
|
|
if (newpriority < curpriority)
|
|
need_resched();
|
|
} else {
|
|
need_resched();
|
|
}
|
|
}
|