move loop invariants in schedcpu; try to make curpri reflect

the current process (still not right); curpri is always a usrpri

SCCS-vsn: sys/kern/kern_synch.c 6.3

diff --git a/usr/src/sys/kern/kern_synch.c b/usr/src/sys/kern/kern_synch.c
index 8ee5e27..9ff8a7a 100644 (file)
--- a/usr/src/sys/kern/kern_synch.c
+++ b/usr/src/sys/kern/kern_synch.c
@@ -1,4 +1,4 @@
-/*     kern_synch.c    6.2     84/05/22        */
+/*     kern_synch.c    6.3     84/07/31        */

 
 #include "../machine/pte.h"
 
 
 #include "../machine/pte.h"
 


@@ -38,6 +38,7 @@ double        ccpu = 0.95122942450071400909;          /* exp(-1/20) */
  */
 schedcpu()
 {
  */
 schedcpu()
 {

+       register double ccpu1 = (1.0 - ccpu) / (double)hz;

        register struct proc *p;
        register int s, a;
 
        register struct proc *p;
        register int s, a;
 


@@ -49,8 +50,7 @@ schedcpu()
                        if (p->p_slptime != 127)
                                p->p_slptime++;
                if (p->p_flag&SLOAD)
                        if (p->p_slptime != 127)
                                p->p_slptime++;
                if (p->p_flag&SLOAD)

-                       p->p_pctcpu = ccpu * p->p_pctcpu +
-                           (1.0 - ccpu) * (p->p_cpticks/(float)hz);
+                       p->p_pctcpu = ccpu * p->p_pctcpu + ccpu1 * p->p_cpticks;

                p->p_cpticks = 0;
                a = ave((p->p_cpu & 0377), avenrun[0]*nrscale) +
                     p->p_nice - NZERO;
                p->p_cpticks = 0;
                a = ave((p->p_cpu & 0377), avenrun[0]*nrscale) +
                     p->p_nice - NZERO;


@@ -62,10 +62,11 @@ schedcpu()
                (void) setpri(p);
                s = spl6();     /* prevent state changes */
                if (p->p_pri >= PUSER) {
                (void) setpri(p);
                s = spl6();     /* prevent state changes */
                if (p->p_pri >= PUSER) {

+#define        PPQ     (128 / NQS)

                        if ((p != u.u_procp || noproc) &&
                            p->p_stat == SRUN &&
                            (p->p_flag & SLOAD) &&
                        if ((p != u.u_procp || noproc) &&
                            p->p_stat == SRUN &&
                            (p->p_flag & SLOAD) &&

-                           p->p_pri != p->p_usrpri) {
+                           (p->p_pri / PPQ) != (p->p_usrpri / PPQ)) {

                                remrq(p);
                                p->p_pri = p->p_usrpri;
                                setrq(p);
                                remrq(p);
                                p->p_pri = p->p_usrpri;
                                setrq(p);


@@ -138,6 +139,7 @@ sleep(chan, pri)
                u.u_ru.ru_nvcsw++;
                swtch();
        }
                u.u_ru.ru_nvcsw++;
                swtch();
        }

+       curpri = rp->p_usrpri;

 out:
        splx(s);
        return;
 out:
        splx(s);
        return;


@@ -197,10 +199,12 @@ restart:
                                p->p_stat = SRUN;
                                if (p->p_flag & SLOAD)
                                        setrq(p);
                                p->p_stat = SRUN;
                                if (p->p_flag & SLOAD)
                                        setrq(p);

-                               if (p->p_pri < curpri) {
-                                       runrun++;
-                                       aston();
-                               }
+                               /*
+                                * Since curpri is a usrpri,
+                                * p->p_pri is always better than curpri.
+                                */
+                               runrun++;
+                               aston();

                                if ((p->p_flag&SLOAD) == 0) {
                                        if (runout != 0) {
                                                runout = 0;
                                if ((p->p_flag&SLOAD) == 0) {
                                        if (runout != 0) {
                                                runout = 0;