BSD 4_4_Lite1 release

[unix-history] / usr / src / sys / kern / kern_synch.c

diff --git a/usr/src/sys/kern/kern_synch.c b/usr/src/sys/kern/kern_synch.c
index 58543dd..1c2a578 100644 (file)
--- a/usr/src/sys/kern/kern_synch.c
+++ b/usr/src/sys/kern/kern_synch.c
@@ -1,11 +1,41 @@
 /*-
  * Copyright (c) 1982, 1986, 1990, 1991, 1993
  *     The Regents of the University of California.  All rights reserved.
 /*-
  * Copyright (c) 1982, 1986, 1990, 1991, 1993
  *     The Regents of the University of California.  All rights reserved.

- * 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.

  *
  *

- * %sccs.include.redist.c%
+ * 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.

  *
  *

- *     @(#)kern_synch.c        8.3 (Berkeley) %G%
+ * 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

  */
 
 #include <sys/param.h>
  */
 
 #include <sys/param.h>


@@ -39,21 +69,21 @@ roundrobin(arg)
 }
 
 /*
 }
 
 /*

- * constants for digital decay and forget
- *     90% of (p_cpu) usage in 5*loadav time
+ * 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).
  *
  *     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_cpu and p_cpticks independently.
+ * Note that hardclock updates p_estcpu and p_cpticks independently.

  *
  *

- * We wish to decay away 90% of p_cpu in (5 * loadavg) seconds.
+ * 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++)
  * 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_cpu *= decay;
+ *             p_estcpu *= decay;

  * will compute
  * will compute

- *     p_cpu *= 0.1;
+ *     p_estcpu *= 0.1;

  * for all values of loadavg:
  *
  * Mathematically this loop can be expressed by saying:
  * for all values of loadavg:
  *
  * Mathematically this loop can be expressed by saying:


@@ -137,13 +167,13 @@ schedcpu(arg)
        register unsigned int newcpu;
 
        wakeup((caddr_t)&lbolt);
        register unsigned int newcpu;
 
        wakeup((caddr_t)&lbolt);

-       for (p = (struct proc *)allproc; p != NULL; p = p->p_nxt) {
+       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.
                 */
                /*
                 * 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_time++;
+               p->p_swtime++;

                if (p->p_stat == SSLEEP || p->p_stat == SSTOP)
                        p->p_slptime++;
                p->p_pctcpu = (p->p_pctcpu * ccpu) >> FSHIFT;
                if (p->p_stat == SSLEEP || p->p_stat == SSTOP)
                        p->p_slptime++;
                p->p_pctcpu = (p->p_pctcpu * ccpu) >> FSHIFT;


@@ -167,20 +197,20 @@ schedcpu(arg)
                        (p->p_cpticks * FSCALE / hz)) >> FSHIFT;
 #endif
                p->p_cpticks = 0;
                        (p->p_cpticks * FSCALE / hz)) >> FSHIFT;
 #endif
                p->p_cpticks = 0;

-               newcpu = (u_int) decay_cpu(loadfac, p->p_cpu) + p->p_nice;
-               p->p_cpu = min(newcpu, UCHAR_MAX);
+               newcpu = (u_int) decay_cpu(loadfac, p->p_estcpu) + p->p_nice;
+               p->p_estcpu = min(newcpu, UCHAR_MAX);

                resetpriority(p);
                resetpriority(p);

-               if (p->p_pri >= PUSER) {
+               if (p->p_priority >= PUSER) {

 #define        PPQ     (128 / NQS)             /* priorities per queue */
                        if ((p != curproc) &&
                            p->p_stat == SRUN &&
 #define        PPQ     (128 / NQS)             /* priorities per queue */
                        if ((p != curproc) &&
                            p->p_stat == SRUN &&

-                           (p->p_flag & SLOAD) &&
-                           (p->p_pri / PPQ) != (p->p_usrpri / PPQ)) {
+                           (p->p_flag & P_INMEM) &&
+                           (p->p_priority / PPQ) != (p->p_usrpri / PPQ)) {

                                remrq(p);
                                remrq(p);

-                               p->p_pri = p->p_usrpri;
+                               p->p_priority = p->p_usrpri;

                                setrunqueue(p);
                        } else
                                setrunqueue(p);
                        } else

-                               p->p_pri = p->p_usrpri;
+                               p->p_priority = p->p_usrpri;

                }
                splx(s);
        }
                }
                splx(s);
        }


@@ -192,33 +222,38 @@ schedcpu(arg)
 
 /*
  * Recalculate the priority of a process after it has slept for a while.
 
 /*
  * Recalculate the priority of a process after it has slept for a while.

- * For all load averages >= 1 and max p_cpu of 255, sleeping for at least
- * six times the loadfactor will decay p_cpu to zero.
+ * 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;
 {
  */
 void
 updatepri(p)
        register struct proc *p;
 {

-       register unsigned int newcpu = p->p_cpu;
+       register unsigned int newcpu = p->p_estcpu;

        register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
 
        if (p->p_slptime > 5 * loadfac)
        register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
 
        if (p->p_slptime > 5 * loadfac)

-               p->p_cpu = 0;
+               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);
        else {
                p->p_slptime--; /* the first time was done in schedcpu */
                while (newcpu && --p->p_slptime)
                        newcpu = (int) decay_cpu(loadfac, newcpu);

-               p->p_cpu = min(newcpu, UCHAR_MAX);
+               p->p_estcpu = min(newcpu, UCHAR_MAX);

        }
        resetpriority(p);
 }
 
        }
        resetpriority(p);
 }
 

-#define SQSIZE 0100    /* Must be power of 2 */
-#define HASH(x)        (( (int) x >> 5) & (SQSIZE-1))
+/*
+ * 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;
 struct slpque {
        struct proc *sq_head;
        struct proc **sq_tailp;

-} slpque[SQSIZE];
+} slpque[TABLESIZE];

 
 /*
  * During autoconfiguration or after a panic, a sleep will simply
 
 /*
  * During autoconfiguration or after a panic, a sleep will simply


@@ -272,19 +307,19 @@ tsleep(ident, priority, wmesg, timo)
                return (0);
        }
 #ifdef DIAGNOSTIC
                return (0);
        }
 #ifdef DIAGNOSTIC

-       if (ident == NULL || p->p_stat != SRUN || p->p_rlink)
+       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;
                panic("tsleep");
 #endif
        p->p_wchan = ident;
        p->p_wmesg = wmesg;
        p->p_slptime = 0;

-       p->p_pri = priority & PRIMASK;
-       qp = &slpque[HASH(ident)];
+       p->p_priority = priority & PRIMASK;
+       qp = &slpque[LOOKUP(ident)];

        if (qp->sq_head == 0)
                qp->sq_head = p;
        else
                *qp->sq_tailp = p;
        if (qp->sq_head == 0)
                qp->sq_head = p;
        else
                *qp->sq_tailp = p;

-       *(qp->sq_tailp = &p->p_link) = 0;
+       *(qp->sq_tailp = &p->p_forw) = 0;

        if (timo)
                timeout(endtsleep, (void *)p, timo);
        /*
        if (timo)
                timeout(endtsleep, (void *)p, timo);
        /*


@@ -297,7 +332,7 @@ tsleep(ident, priority, wmesg, timo)
         * stopped, p->p_wchan will be 0 upon return from CURSIG.
         */
        if (catch) {
         * stopped, p->p_wchan will be 0 upon return from CURSIG.
         */
        if (catch) {

-               p->p_flag |= SSINTR;
+               p->p_flag |= P_SINTR;

                if (sig = CURSIG(p)) {
                        if (p->p_wchan)
                                unsleep(p);
                if (sig = CURSIG(p)) {
                        if (p->p_wchan)
                                unsleep(p);


@@ -312,13 +347,13 @@ tsleep(ident, priority, wmesg, timo)
                sig = 0;
        p->p_stat = SSLEEP;
        p->p_stats->p_ru.ru_nvcsw++;
                sig = 0;
        p->p_stat = SSLEEP;
        p->p_stats->p_ru.ru_nvcsw++;

-       swtch();
+       mi_switch();

 resume:
        curpriority = p->p_usrpri;
        splx(s);
 resume:
        curpriority = p->p_usrpri;
        splx(s);

-       p->p_flag &= ~SSINTR;
-       if (p->p_flag & STIMO) {
-               p->p_flag &= ~STIMO;
+       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))
                if (sig == 0) {
 #ifdef KTRACE
                        if (KTRPOINT(p, KTR_CSW))


@@ -364,7 +399,7 @@ endtsleep(arg)
                        setrunnable(p);
                else
                        unsleep(p);
                        setrunnable(p);
                else
                        unsleep(p);

-               p->p_flag |= STIMO;
+               p->p_flag |= P_TIMEOUT;

        }
        splx(s);
 }
        }
        splx(s);
 }


@@ -402,26 +437,26 @@ sleep(ident, priority)
                return;
        }
 #ifdef DIAGNOSTIC
                return;
        }
 #ifdef DIAGNOSTIC

-       if (ident == NULL || p->p_stat != SRUN || p->p_rlink)
+       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;
                panic("sleep");
 #endif
        p->p_wchan = ident;
        p->p_wmesg = NULL;
        p->p_slptime = 0;

-       p->p_pri = priority;
-       qp = &slpque[HASH(ident)];
+       p->p_priority = priority;
+       qp = &slpque[LOOKUP(ident)];

        if (qp->sq_head == 0)
                qp->sq_head = p;
        else
                *qp->sq_tailp = p;
        if (qp->sq_head == 0)
                qp->sq_head = p;
        else
                *qp->sq_tailp = p;

-       *(qp->sq_tailp = &p->p_link) = 0;
+       *(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
        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

-       swtch();
+       mi_switch();

 #ifdef KTRACE
        if (KTRPOINT(p, KTR_CSW))
                ktrcsw(p->p_tracep, 0, 0);
 #ifdef KTRACE
        if (KTRPOINT(p, KTR_CSW))
                ktrcsw(p->p_tracep, 0, 0);


@@ -443,11 +478,11 @@ unsleep(p)
 
        s = splhigh();
        if (p->p_wchan) {
 
        s = splhigh();
        if (p->p_wchan) {

-               hp = &(qp = &slpque[HASH(p->p_wchan)])->sq_head;
+               hp = &(qp = &slpque[LOOKUP(p->p_wchan)])->sq_head;

                while (*hp != p)
                while (*hp != p)

-                       hp = &(*hp)->p_link;
-               *hp = p->p_link;
-               if (qp->sq_tailp == &p->p_link)
+                       hp = &(*hp)->p_forw;
+               *hp = p->p_forw;
+               if (qp->sq_tailp == &p->p_forw)

                        qp->sq_tailp = hp;
                p->p_wchan = 0;
        }
                        qp->sq_tailp = hp;
                p->p_wchan = 0;
        }


@@ -466,17 +501,17 @@ wakeup(ident)
        int s;
 
        s = splhigh();
        int s;
 
        s = splhigh();

-       qp = &slpque[HASH(ident)];
+       qp = &slpque[LOOKUP(ident)];

 restart:
        for (q = &qp->sq_head; p = *q; ) {
 #ifdef DIAGNOSTIC
 restart:
        for (q = &qp->sq_head; p = *q; ) {
 #ifdef DIAGNOSTIC

-               if (p->p_rlink || p->p_stat != SSLEEP && p->p_stat != SSTOP)
+               if (p->p_back || p->p_stat != SSLEEP && p->p_stat != SSTOP)

                        panic("wakeup");
 #endif
                if (p->p_wchan == ident) {
                        p->p_wchan = 0;
                        panic("wakeup");
 #endif
                if (p->p_wchan == ident) {
                        p->p_wchan = 0;

-                       *q = p->p_link;
-                       if (qp->sq_tailp == &p->p_link)
+                       *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); */
                                qp->sq_tailp = q;
                        if (p->p_stat == SSLEEP) {
                                /* OPTIMIZED EXPANSION OF setrunnable(p); */


@@ -484,13 +519,14 @@ restart:
                                        updatepri(p);
                                p->p_slptime = 0;
                                p->p_stat = SRUN;
                                        updatepri(p);
                                p->p_slptime = 0;
                                p->p_stat = SRUN;

-                               if (p->p_flag & SLOAD)
+                               if (p->p_flag & P_INMEM)

                                        setrunqueue(p);
                                /*
                                 * Since curpriority is a user priority,
                                        setrunqueue(p);
                                /*
                                 * Since curpriority is a user priority,

-                                * p->p_pri is always better than curpriority.
+                                * p->p_priority is always better than
+                                * curpriority.

                                 */
                                 */

-                               if ((p->p_flag&SLOAD) == 0)
+                               if ((p->p_flag & P_INMEM) == 0)

                                        wakeup((caddr_t)&proc0);
                                else
                                        need_resched();
                                        wakeup((caddr_t)&proc0);
                                else
                                        need_resched();


@@ -498,17 +534,17 @@ restart:
                                goto restart;
                        }
                } else
                                goto restart;
                        }
                } else

-                       q = &p->p_link;
+                       q = &p->p_forw;

        }
        splx(s);
 }
 
 /*
        }
        splx(s);
 }
 
 /*

- * The machine independent parts of swtch().
+ * The machine independent parts of mi_switch().

  * Must be called at splstatclock() or higher.
  */
 void
  * Must be called at splstatclock() or higher.
  */
 void

-swtch()
+mi_switch()

 {
        register struct proc *p = curproc;      /* XXX */
        register struct rlimit *rlim;
 {
        register struct proc *p = curproc;      /* XXX */
        register struct rlimit *rlim;


@@ -556,7 +592,7 @@ swtch()
         * Pick a new current process and record its start time.
         */
        cnt.v_swtch++;
         * Pick a new current process and record its start time.
         */
        cnt.v_swtch++;

-       cpu_swtch(p);
+       cpu_switch(p);

        microtime(&runtime);
 }
 
        microtime(&runtime);
 }
 


@@ -599,15 +635,15 @@ setrunnable(p)
                break;
        }
        p->p_stat = SRUN;
                break;
        }
        p->p_stat = SRUN;

-       if (p->p_flag & SLOAD)
+       if (p->p_flag & P_INMEM)

                setrunqueue(p);
        splx(s);
        if (p->p_slptime > 1)
                updatepri(p);
        p->p_slptime = 0;
                setrunqueue(p);
        splx(s);
        if (p->p_slptime > 1)
                updatepri(p);
        p->p_slptime = 0;

-       if ((p->p_flag&SLOAD) == 0)
+       if ((p->p_flag & P_INMEM) == 0)

                wakeup((caddr_t)&proc0);
                wakeup((caddr_t)&proc0);

-       else if (p->p_pri < curpriority)
+       else if (p->p_priority < curpriority)

                need_resched();
 }
 
                need_resched();
 }
 


@@ -622,7 +658,7 @@ resetpriority(p)
 {
        register unsigned int newpriority;
 
 {
        register unsigned int newpriority;
 

-       newpriority = PUSER + p->p_cpu / 4 + 2 * p->p_nice;
+       newpriority = PUSER + p->p_estcpu / 4 + 2 * p->p_nice;

        newpriority = min(newpriority, MAXPRI);
        p->p_usrpri = newpriority;
        if (newpriority < curpriority)
        newpriority = min(newpriority, MAXPRI);
        p->p_usrpri = newpriority;
        if (newpriority < curpriority)