tsleep II, as it was meant to be

SCCS-vsn: sys/kern/kern_synch.c 7.11

diff --git a/usr/src/sys/kern/kern_synch.c b/usr/src/sys/kern/kern_synch.c
index 284a326..61b3f79 100644 (file)
--- a/usr/src/sys/kern/kern_synch.c
+++ b/usr/src/sys/kern/kern_synch.c
@@ -1,9 +1,9 @@
 /*
 /*

- * Copyright (c) 1982, 1986 Regents of the University of California.
+ * Copyright (c) 1982, 1986, 1990 Regents of the University of California.

  * All rights reserved.  The Berkeley software License Agreement
  * specifies the terms and conditions for redistribution.
  *
  * All rights reserved.  The Berkeley software License Agreement
  * specifies the terms and conditions for redistribution.
  *

- *     @(#)kern_synch.c        7.10 (Berkeley) %G%
+ *     @(#)kern_synch.c        7.11 (Berkeley) %G%

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


@@ -17,7 +17,6 @@
 #include "vm.h"
 #include "kernel.h"
 #include "buf.h"
 #include "vm.h"
 #include "kernel.h"
 #include "buf.h"

-#include "tsleep.h"

 
 /*
  * Force switch among equal priority processes every 100ms.
 
 /*
  * Force switch among equal priority processes every 100ms.


@@ -212,42 +211,19 @@ struct slpque {
 } slpque[SQSIZE];
 
 /*
 } slpque[SQSIZE];
 
 /*

- * XXX - redo comments once interface is set
- * 
- * Give up the processor till a wakeup occurs
- * on chan, at which time the process
- * enters the scheduling queue at priority pri.
- * The most important effect of pri is that when
- * pri<=PZERO a signal cannot disturb the sleep;
- * if pri>PZERO signals will be processed.
- * Callers of this routine must be prepared for
- * premature return, and check that the reason for
- * sleeping has gone away.
+ * General sleep call.
+ * Suspends current process until a wakeup is made on chan.
+ * The process will then be made runnable with priority pri.
+ * 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).

  */
  */

-
-/*
- * interruptable sleep with longjmp processing.
- * TEMPORARY UNTIL ALL CALLERS ARE TAUGHT TO UNWIND
- */
-tsleep(chan, pri, wmesg, timeout)
-       caddr_t chan;
-       int pri;
-       char *wmesg;
-       int timeout;
-{
-       if (pri <= PZERO) 
-               panic("tsleep: pri <= PZERO");
-       if (isleep(chan, pri, wmesg, timeout) == EINTR)
-               longjmp(&u.u_qsave);
-}
-
-/*
- * Interruptable sleep.
- * Sleeps on chan for time of at most timo/hz seconds (0 means no timeout).
- * Returns 0 if awakened, EINTR if a signal needs to be delivered,
- * or EWOULDBLOCK if the timeout expires.
- */
-isleep(chan, pri, wmesg, timo)
+tsleep(chan, pri, wmesg, timo)

        caddr_t chan;
        int pri;
        char *wmesg;
        caddr_t chan;
        int pri;
        char *wmesg;


@@ -256,6 +232,7 @@ isleep(chan, pri, wmesg, timo)
        register struct proc *rp;
        register struct slpque *qp;
        register s;
        register struct proc *rp;
        register struct slpque *qp;
        register s;

+       int sig, catch = pri & PCATCH;

        extern int cold;
        int endtsleep();
 
        extern int cold;
        int endtsleep();
 


@@ -267,22 +244,19 @@ isleep(chan, pri, wmesg, timo)
                 * 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.
                 * 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.

-                * The splnet should be spl0 if the network was being used
-                * by the filesystem, but for now avoid network interrupts
-                * that might cause another panic.

                 */
                 */

-               (void) splnet();
+               (void) spl0();

                splx(s);
                return (0);
        }
 #ifdef DIAGNOSTIC
                splx(s);
                return (0);
        }
 #ifdef DIAGNOSTIC

-       if (chan==0 || rp->p_stat != SRUN || rp->p_rlink)
-               panic("isleep");
+       if (chan == 0 || rp->p_stat != SRUN || rp->p_rlink)
+               panic("tsleep");

 #endif
        rp->p_wchan = chan;
        rp->p_wmesg = wmesg;
        rp->p_slptime = 0;
 #endif
        rp->p_wchan = chan;
        rp->p_wmesg = wmesg;
        rp->p_slptime = 0;

-       rp->p_pri = pri;
+       rp->p_pri = pri & PRIMASK;

        qp = &slpque[HASH(chan)];
        if (qp->sq_head == 0)
                qp->sq_head = rp;
        qp = &slpque[HASH(chan)];
        if (qp->sq_head == 0)
                qp->sq_head = rp;


@@ -290,19 +264,25 @@ isleep(chan, pri, wmesg, timo)
                *qp->sq_tailp = rp;
        *(qp->sq_tailp = &rp->p_link) = 0;
        /*
                *qp->sq_tailp = rp;
        *(qp->sq_tailp = &rp->p_link) = 0;
        /*

-        * If we stop in issig(), wakeup may already have happened
-        * when we return (rp->p_wchan will then be 0).
+        * If we stop in CURSIG/issig(), wakeup may already
+        * have happened when we return.
+        * rp->p_wchan will then be 0.

         */
         */

-       if (CURSIG(rp)) {
-               if (rp->p_wchan)
-                       unsleep(rp);
-               rp->p_stat = SRUN;
-               splx(s);
-               return (EINTR);
-       }
-       if (rp->p_wchan == 0) {
-               splx(s);
-               return (0);
+       if (catch) {
+               if (sig = CURSIG(rp)) {
+                       if (rp->p_wchan)
+                               unsleep(rp);
+                       rp->p_stat = SRUN;
+                       splx(s);
+                       if (u.u_sigintr & sigmask(sig))
+                               return (EINTR);
+                       return (ERESTART);
+               }
+               if (rp->p_wchan == 0) {
+                       splx(s);
+                       return (0);
+               }
+               rp->p_flag |= SSINTR;

        }
        rp->p_stat = SSLEEP;
        if (timo)
        }
        rp->p_stat = SSLEEP;
        if (timo)


@@ -312,14 +292,18 @@ isleep(chan, pri, wmesg, timo)
        swtch();
        curpri = rp->p_usrpri;
        splx(s);
        swtch();
        curpri = rp->p_usrpri;
        splx(s);

+       rp->p_flag &= ~SSINTR;

        if (rp->p_flag & STIMO) {
                rp->p_flag &= ~STIMO;
                return (EWOULDBLOCK);
        }
        if (timo)
                untimeout(endtsleep, (caddr_t)rp);
        if (rp->p_flag & STIMO) {
                rp->p_flag &= ~STIMO;
                return (EWOULDBLOCK);
        }
        if (timo)
                untimeout(endtsleep, (caddr_t)rp);

-       if (CURSIG(rp))
-               return (EINTR);
+       if (catch && (sig = CURSIG(rp))) {
+               if (u.u_sigintr & sigmask(sig))
+                       return (EINTR);
+               return (ERESTART);
+       }

        return (0);
 }
 
        return (0);
 }
 


@@ -344,8 +328,9 @@ endtsleep(p)
        splx(s);
 }
 
        splx(s);
 }
 

-int sleepdebug = 1;    /* XXX */
-
+/*
+ * Short-term, non-interruptable sleep.
+ */

 sleep(chan, pri)
        caddr_t chan;
        int pri;
 sleep(chan, pri)
        caddr_t chan;
        int pri;


@@ -355,6 +340,13 @@ sleep(chan, pri)
        register s;
        extern int cold;
 
        register s;
        extern int cold;
 

+#ifdef DIAGNOSTIC
+       if (pri > PZERO) {
+               printf("sleep called with pri %d > PZERO, wchan: %x\n",
+                       pri, chan);
+               panic("old sleep");
+       }
+#endif

        rp = u.u_procp;
        s = splhigh();
        if (cold || panicstr) {
        rp = u.u_procp;
        s = splhigh();
        if (cold || panicstr) {


@@ -363,11 +355,8 @@ sleep(chan, pri)
                 * 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.
                 * 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.

-                * The splnet should be spl0 if the network was being used
-                * by the filesystem, but for now avoid network interrupts
-                * that might cause another panic.

                 */
                 */

-               (void) splnet();
+               (void) spl0();

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


@@ -385,48 +374,12 @@ sleep(chan, pri)
        else
                *qp->sq_tailp = rp;
        *(qp->sq_tailp = &rp->p_link) = 0;
        else
                *qp->sq_tailp = rp;
        *(qp->sq_tailp = &rp->p_link) = 0;

-       if (pri > PZERO) {
-               if (sleepdebug)
-                       printf("sleep called with pri > PZERO, wchan: %x\n",
-                               chan);
-               /*
-                * If we stop in issig(), wakeup may already have happened
-                * when we return (rp->p_wchan will then be 0).
-                */
-               if (CURSIG(rp)) {
-                       if (rp->p_wchan)
-                               unsleep(rp);
-                       rp->p_stat = SRUN;
-                       (void) spl0();
-                       goto psig;
-               }
-               if (rp->p_wchan == 0)
-                       goto out;
-               rp->p_stat = SSLEEP;
-               (void) spl0();
-               u.u_ru.ru_nvcsw++;
-               swtch();
-               if (CURSIG(rp))
-                       goto psig;
-       } else {
-               rp->p_stat = SSLEEP;
-               (void) spl0();
-               u.u_ru.ru_nvcsw++;
-               swtch();
-       }
+       rp->p_stat = SSLEEP;
+       (void) spl0();
+       u.u_ru.ru_nvcsw++;
+       swtch();

        curpri = rp->p_usrpri;
        curpri = rp->p_usrpri;

-out:

        splx(s);
        splx(s);

-       return;
-
-       /*
-        * If priority was low (>PZERO) and
-        * there has been a signal, execute non-local goto through
-        * u.u_qsave, aborting the system call in progress (see trap.c)
-        */
-psig:
-       longjmp(&u.u_qsave);
-       /*NOTREACHED*/

 }
 
 /*
 }
 
 /*