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patch delete-swapped_lock
patch sched-cleanup
patch remove-useless-var2
patch remove-dead-sched-code
patch remove-as_swapout
patch remove-load-flag
patch remove-on-swapq-flag
patch remove-swapenq-flag
patch remove-dont-swap-flag
patch remove-swapinout-class-ops
patch remove-useless-var

@@ -52,445 +52,41 @@
 #include <vm/as.h>
 #include <vm/rm.h>
 #include <vm/seg_kmem.h>
 #include <sys/callb.h>
 
-/*
- * The swapper sleeps on runout when there is no one to swap in.
- * It sleeps on runin when it could not find space to swap someone
- * in or after swapping someone in.
- */
-char    runout;
-char    runin;
-char    wake_sched;     /* flag tells clock to wake swapper on next tick */
-char    wake_sched_sec; /* flag tells clock to wake swapper after a second */
-
-/*
- * The swapper swaps processes to reduce memory demand and runs
- * when avefree < desfree.  The swapper resorts to SOFTSWAP when
- * avefree < desfree which results in swapping out all processes
- * sleeping for more than maxslp seconds.  HARDSWAP occurs when the
- * system is on the verge of thrashing and this results in swapping
- * out runnable threads or threads sleeping for less than maxslp secs.
- *
- * The swapper runs through all the active processes in the system
- * and invokes the scheduling class specific swapin/swapout routine
- * for every thread in the process to obtain an effective priority
- * for the process.  A priority of -1 implies that the thread isn't
- * swappable.  This effective priority is used to find the most
- * eligible process to swapout or swapin.
- *
- * NOTE:  Threads which have been swapped are not linked on any
- *        queue and their dispatcher lock points at the "swapped_lock".
- *
- * Processes containing threads with the TS_DONT_SWAP flag set cannot be
- * swapped out immediately by the swapper.  This is due to the fact that
- * such threads may be holding locks which may be needed by the swapper
- * to push its pages out.  The TS_SWAPENQ flag is set on such threads
- * to prevent them running in user mode.  When such threads reach a
- * safe point (i.e., are not holding any locks - CL_TRAPRET), they
- * queue themseleves onto the swap queue which is processed by the
- * swapper.  This results in reducing memory demand when the system
- * is desparate for memory as the thread can't run in user mode.
- *
- * The swap queue consists of threads, linked via t_link, which are
- * haven't been swapped, are runnable but not on the run queue.  The
- * swap queue is protected by the "swapped_lock".  The dispatcher
- * lock (t_lockp) of all threads on the swap queue points at the
- * "swapped_lock".  Thus, the entire queue and/or threads on the
- * queue can be locked by acquiring "swapped_lock".
- */
-static kthread_t *tswap_queue;
-extern disp_lock_t swapped_lock; /* protects swap queue and threads on it */
-
-int     maxslp = 0;
 pgcnt_t avefree;        /* 5 sec moving average of free memory */
 pgcnt_t avefree30;      /* 30 sec moving average of free memory */
 
 /*
- * Minimum size used to decide if sufficient memory is available
- * before a process is swapped in.  This is necessary since in most
- * cases the actual size of a process (p_swrss) being swapped in
- * is usually 2 pages (kernel stack pages).  This is due to the fact
- * almost all user pages of a process are stolen by pageout before
- * the swapper decides to swapout it out.
- */
-int     min_procsize = 12;
-
-static int      swapin(proc_t *);
-static int      swapout(proc_t *, uint_t *, int);
-static void     process_swap_queue();
-
-#ifdef __sparc
-extern void lwp_swapin(kthread_t *);
-#endif /* __sparc */
-
-/*
- * Counters to keep track of the number of swapins or swapouts.
- */
-uint_t tot_swapped_in, tot_swapped_out;
-uint_t softswap, hardswap, swapqswap;
-
-/*
- * Macro to determine if a process is eligble to be swapped.
- */
-#define not_swappable(p)                                        \
-        (((p)->p_flag & SSYS) || (p)->p_stat == SIDL ||         \
-            (p)->p_stat == SZOMB || (p)->p_as == NULL ||        \
-            (p)->p_as == &kas)
-
-/*
  * Memory scheduler.
  */
 void
 sched()
 {
         kthread_id_t    t;
-        pri_t           proc_pri;
-        pri_t           thread_pri;
-        pri_t           swapin_pri;
-        int             desperate;
-        pgcnt_t         needs;
-        int             divisor;
-        proc_t          *prp;
-        proc_t          *swapout_prp;
-        proc_t          *swapin_prp;
-        spgcnt_t        avail;
-        int             chosen_pri;
-        time_t          swapout_time;
-        time_t          swapin_proc_time;
         callb_cpr_t     cprinfo;
         kmutex_t        swap_cpr_lock;
 
         mutex_init(&swap_cpr_lock, NULL, MUTEX_DEFAULT, NULL);
         CALLB_CPR_INIT(&cprinfo, &swap_cpr_lock, callb_generic_cpr, "sched");
-        if (maxslp == 0)
-                maxslp = MAXSLP;
-loop:
-        needs = 0;
-        desperate = 0;
 
-        swapin_pri = v.v_nglobpris;
-        swapin_prp = NULL;
-        chosen_pri = -1;
-
-        process_swap_queue();
-
-        /*
-         * Set desperate if
-         *      1.  At least 2 runnable processes (on average).
-         *      2.  Short (5 sec) and longer (30 sec) average is less
-         *          than minfree and desfree respectively.
-         *      3.  Pagein + pageout rate is excessive.
-         */
+        for (;;) {
         if (avenrun[0] >= 2 * FSCALE &&
             (MAX(avefree, avefree30) < desfree) &&
             (pginrate + pgoutrate > maxpgio || avefree < minfree)) {
-                TRACE_4(TR_FAC_SCHED, TR_DESPERATE,
-                    "desp:avefree: %d, avefree30: %d, freemem: %d"
-                    " pginrate: %d\n", avefree, avefree30, freemem, pginrate);
-                desperate = 1;
-                goto unload;
-        }
-
-        /*
-         * Search list of processes to swapin and swapout deadwood.
-         */
-        swapin_proc_time = 0;
-top:
-        mutex_enter(&pidlock);
-        for (prp = practive; prp != NULL; prp = prp->p_next) {
-                if (not_swappable(prp))
-                        continue;
-
-                /*
-                 * Look at processes with at least one swapped lwp.
-                 */
-                if (prp->p_swapcnt) {
-                        time_t proc_time;
-
-                        /*
-                         * Higher priority processes are good candidates
-                         * to swapin.
-                         */
-                        mutex_enter(&prp->p_lock);
-                        proc_pri = -1;
-                        t = prp->p_tlist;
-                        proc_time = 0;
-                        do {
-                                if (t->t_schedflag & TS_LOAD)
-                                        continue;
-
-                                thread_lock(t);
-                                thread_pri = CL_SWAPIN(t, 0);
-                                thread_unlock(t);
-
-                                if (t->t_stime - proc_time > 0)
-                                        proc_time = t->t_stime;
-                                if (thread_pri > proc_pri)
-                                        proc_pri = thread_pri;
-                        } while ((t = t->t_forw) != prp->p_tlist);
-                        mutex_exit(&prp->p_lock);
-
-                        if (proc_pri == -1)
-                                continue;
-
-                        TRACE_3(TR_FAC_SCHED, TR_CHOOSE_SWAPIN,
-                            "prp %p epri %d proc_time %d",
-                            prp, proc_pri, proc_time);
-
-                        /*
-                         * Swapin processes with a high effective priority.
-                         */
-                        if (swapin_prp == NULL || proc_pri > chosen_pri) {
-                                swapin_prp = prp;
-                                chosen_pri = proc_pri;
-                                swapin_pri = proc_pri;
-                                swapin_proc_time = proc_time;
-                        }
-                } else {
-                        /*
-                         * No need to soft swap if we have sufficient
-                         * memory.
-                         */
-                        if (avefree > desfree ||
-                            avefree < desfree && freemem > desfree)
-                                continue;
-
-                        /*
-                         * Skip processes that are exiting
-                         * or whose address spaces are locked.
-                         */
-                        mutex_enter(&prp->p_lock);
-                        if ((prp->p_flag & SEXITING) ||
-                            (prp->p_as != NULL && AS_ISPGLCK(prp->p_as))) {
-                                mutex_exit(&prp->p_lock);
-                                continue;
-                        }
-
-                        /*
-                         * Softswapping to kick out deadwood.
-                         */
-                        proc_pri = -1;
-                        t = prp->p_tlist;
-                        do {
-                                if ((t->t_schedflag & (TS_SWAPENQ |
-                                    TS_ON_SWAPQ | TS_LOAD)) != TS_LOAD)
-                                        continue;
-
-                                thread_lock(t);
-                                thread_pri = CL_SWAPOUT(t, SOFTSWAP);
-                                thread_unlock(t);
-                                if (thread_pri > proc_pri)
-                                        proc_pri = thread_pri;
-                        } while ((t = t->t_forw) != prp->p_tlist);
-
-                        if (proc_pri != -1) {
-                                uint_t swrss;
-
-                                mutex_exit(&pidlock);
-
-                                TRACE_1(TR_FAC_SCHED, TR_SOFTSWAP,
-                                    "softswap:prp %p", prp);
-
-                                (void) swapout(prp, &swrss, SOFTSWAP);
-                                softswap++;
-                                prp->p_swrss += swrss;
-                                mutex_exit(&prp->p_lock);
-                                goto top;
-                        }
-                        mutex_exit(&prp->p_lock);
-                }
-        }
-        if (swapin_prp != NULL)
-                mutex_enter(&swapin_prp->p_lock);
-        mutex_exit(&pidlock);
-
-        if (swapin_prp == NULL) {
-                TRACE_3(TR_FAC_SCHED, TR_RUNOUT,
-                "schedrunout:runout nswapped: %d, avefree: %ld freemem: %ld",
-                    nswapped, avefree, freemem);
-
-                t = curthread;
-                thread_lock(t);
-                runout++;
-                t->t_schedflag |= (TS_ALLSTART & ~TS_CSTART);
-                t->t_whystop = PR_SUSPENDED;
-                t->t_whatstop = SUSPEND_NORMAL;
-                (void) new_mstate(t, LMS_SLEEP);
-                mutex_enter(&swap_cpr_lock);
-                CALLB_CPR_SAFE_BEGIN(&cprinfo);
-                mutex_exit(&swap_cpr_lock);
-                thread_stop(t);         /* change state and drop lock */
-                swtch();
-                mutex_enter(&swap_cpr_lock);
-                CALLB_CPR_SAFE_END(&cprinfo, &swap_cpr_lock);
-                mutex_exit(&swap_cpr_lock);
-                goto loop;
-        }
-
-        /*
-         * Decide how deserving this process is to be brought in.
-         * Needs is an estimate of how much core the process will
-         * need.  If the process has been out for a while, then we
-         * will bring it in with 1/2 the core needed, otherwise
-         * we are conservative.
-         */
-        divisor = 1;
-        swapout_time = (ddi_get_lbolt() - swapin_proc_time) / hz;
-        if (swapout_time > maxslp / 2)
-                divisor = 2;
-
-        needs = MIN(swapin_prp->p_swrss, lotsfree);
-        needs = MAX(needs, min_procsize);
-        needs = needs / divisor;
-
-        /*
-         * Use freemem, since we want processes to be swapped
-         * in quickly.
-         */
-        avail = freemem - deficit;
-        if (avail > (spgcnt_t)needs) {
-                deficit += needs;
-
-                TRACE_2(TR_FAC_SCHED, TR_SWAPIN_VALUES,
-                    "swapin_values: prp %p needs %lu", swapin_prp, needs);
-
-                if (swapin(swapin_prp)) {
-                        mutex_exit(&swapin_prp->p_lock);
-                        goto loop;
-                }
-                deficit -= MIN(needs, deficit);
-                mutex_exit(&swapin_prp->p_lock);
-        } else {
-                mutex_exit(&swapin_prp->p_lock);
-                /*
-                 * If deficit is high, too many processes have been
-                 * swapped in so wait a sec before attempting to
-                 * swapin more.
-                 */
-                if (freemem > needs) {
-                        TRACE_2(TR_FAC_SCHED, TR_HIGH_DEFICIT,
-                            "deficit: prp %p needs %lu", swapin_prp, needs);
-                        goto block;
-                }
-        }
-
-        TRACE_2(TR_FAC_SCHED, TR_UNLOAD,
-            "unload: prp %p needs %lu", swapin_prp, needs);
-
-unload:
         /*
          * Unload all unloadable modules, free all other memory
-         * resources we can find, then look for a thread to hardswap.
+                         * resources we can find, then look for a thread to
+                         * hardswap.
          */
         modreap();
         segkp_cache_free();
-
-        swapout_prp = NULL;
-        mutex_enter(&pidlock);
-        for (prp = practive; prp != NULL; prp = prp->p_next) {
-
-                /*
-                 * No need to soft swap if we have sufficient
-                 * memory.
-                 */
-                if (not_swappable(prp))
-                        continue;
-
-                if (avefree > minfree ||
-                    avefree < minfree && freemem > desfree) {
-                        swapout_prp = NULL;
-                        break;
-                }
-
-                /*
-                 * Skip processes that are exiting
-                 * or whose address spaces are locked.
-                 */
-                mutex_enter(&prp->p_lock);
-                if ((prp->p_flag & SEXITING) ||
-                    (prp->p_as != NULL && AS_ISPGLCK(prp->p_as))) {
-                        mutex_exit(&prp->p_lock);
-                        continue;
-                }
-
-                proc_pri = -1;
-                t = prp->p_tlist;
-                do {
-                        if ((t->t_schedflag & (TS_SWAPENQ |
-                            TS_ON_SWAPQ | TS_LOAD)) != TS_LOAD)
-                                continue;
-
-                        thread_lock(t);
-                        thread_pri = CL_SWAPOUT(t, HARDSWAP);
-                        thread_unlock(t);
-                        if (thread_pri > proc_pri)
-                                proc_pri = thread_pri;
-                } while ((t = t->t_forw) != prp->p_tlist);
-
-                mutex_exit(&prp->p_lock);
-                if (proc_pri == -1)
-                        continue;
-
-                /*
-                 * Swapout processes sleeping with a lower priority
-                 * than the one currently being swapped in, if any.
-                 */
-                if (swapin_prp == NULL || swapin_pri > proc_pri) {
-                        TRACE_2(TR_FAC_SCHED, TR_CHOOSE_SWAPOUT,
-                            "hardswap: prp %p needs %lu", prp, needs);
-
-                        if (swapout_prp == NULL || proc_pri < chosen_pri) {
-                                swapout_prp = prp;
-                                chosen_pri = proc_pri;
-                        }
-                }
-        }
-
-        /*
-         * Acquire the "p_lock" before dropping "pidlock"
-         * to prevent the proc structure from being freed
-         * if the process exits before swapout completes.
-         */
-        if (swapout_prp != NULL)
-                mutex_enter(&swapout_prp->p_lock);
-        mutex_exit(&pidlock);
-
-        if ((prp = swapout_prp) != NULL) {
-                uint_t swrss = 0;
-                int swapped;
-
-                swapped = swapout(prp, &swrss, HARDSWAP);
-                if (swapped) {
-                        /*
-                         * If desperate, we want to give the space obtained
-                         * by swapping this process out to processes in core,
-                         * so we give them a chance by increasing deficit.
-                         */
-                        prp->p_swrss += swrss;
-                        if (desperate)
-                                deficit += MIN(prp->p_swrss, lotsfree);
-                        hardswap++;
-                }
-                mutex_exit(&swapout_prp->p_lock);
-
-                if (swapped)
-                        goto loop;
         }
 
-        /*
-         * Delay for 1 second and look again later.
-         */
-        TRACE_3(TR_FAC_SCHED, TR_RUNIN,
-            "schedrunin:runin nswapped: %d, avefree: %ld freemem: %ld",
-            nswapped, avefree, freemem);
-
-block:
         t = curthread;
         thread_lock(t);
-        runin++;
         t->t_schedflag |= (TS_ALLSTART & ~TS_CSTART);
         t->t_whystop = PR_SUSPENDED;
         t->t_whatstop = SUSPEND_NORMAL;
         (void) new_mstate(t, LMS_SLEEP);
         mutex_enter(&swap_cpr_lock);

@@ -499,441 +95,7 @@
         thread_stop(t);         /* change to stop state and drop lock */
         swtch();
         mutex_enter(&swap_cpr_lock);
         CALLB_CPR_SAFE_END(&cprinfo, &swap_cpr_lock);
         mutex_exit(&swap_cpr_lock);
-        goto loop;
-}
-
-/*
- * Remove the specified thread from the swap queue.
- */
-static void
-swapdeq(kthread_id_t tp)
-{
-        kthread_id_t *tpp;
-
-        ASSERT(THREAD_LOCK_HELD(tp));
-        ASSERT(tp->t_schedflag & TS_ON_SWAPQ);
-
-        tpp = &tswap_queue;
-        for (;;) {
-                ASSERT(*tpp != NULL);
-                if (*tpp == tp)
-                        break;
-                tpp = &(*tpp)->t_link;
-        }
-        *tpp = tp->t_link;
-        tp->t_schedflag &= ~TS_ON_SWAPQ;
-}
-
-/*
- * Swap in lwps.  Returns nonzero on success (i.e., if at least one lwp is
- * swapped in) and 0 on failure.
- */
-static int
-swapin(proc_t *pp)
-{
-        kthread_id_t tp;
-        int err;
-        int num_swapped_in = 0;
-        struct cpu *cpup = CPU;
-        pri_t thread_pri;
-
-        ASSERT(MUTEX_HELD(&pp->p_lock));
-        ASSERT(pp->p_swapcnt);
-
-top:
-        tp = pp->p_tlist;
-        do {
-                /*
-                 * Only swapin eligible lwps (specified by the scheduling
-                 * class) which are unloaded and ready to run.
-                 */
-                thread_lock(tp);
-                thread_pri = CL_SWAPIN(tp, 0);
-                if (thread_pri != -1 && tp->t_state == TS_RUN &&
-                    (tp->t_schedflag & TS_LOAD) == 0) {
-                        size_t stack_size;
-                        pgcnt_t stack_pages;
-
-                        ASSERT((tp->t_schedflag & TS_ON_SWAPQ) == 0);
-
-                        thread_unlock(tp);
-                        /*
-                         * Now drop the p_lock since the stack needs
-                         * to brought in.
-                         */
-                        mutex_exit(&pp->p_lock);
-
-                        stack_size = swapsize(tp->t_swap);
-                        stack_pages = btopr(stack_size);
-                        /* Kernel probe */
-                        TNF_PROBE_4(swapin_lwp, "vm swap swapin", /* CSTYLED */,
-                            tnf_pid,            pid,            pp->p_pid,
-                            tnf_lwpid,          lwpid,          tp->t_tid,
-                            tnf_kthread_id,     tid,            tp,
-                            tnf_ulong,          page_count,     stack_pages);
-
-                        rw_enter(&kas.a_lock, RW_READER);
-                        err = segkp_fault(segkp->s_as->a_hat, segkp,
-                            tp->t_swap, stack_size, F_SOFTLOCK, S_OTHER);
-                        rw_exit(&kas.a_lock);
-
-                        /*
-                         * Re-acquire the p_lock.
-                         */
-                        mutex_enter(&pp->p_lock);
-                        if (err) {
-                                num_swapped_in = 0;
-                                break;
-                        } else {
-#ifdef __sparc
-                                lwp_swapin(tp);
-#endif /* __sparc */
-                                CPU_STATS_ADDQ(cpup, vm, swapin, 1);
-                                CPU_STATS_ADDQ(cpup, vm, pgswapin,
-                                    stack_pages);
-
-                                pp->p_swapcnt--;
-                                pp->p_swrss -= stack_pages;
-
-                                thread_lock(tp);
-                                tp->t_schedflag |= TS_LOAD;
-                                dq_sruninc(tp);
-
-                                /* set swapin time */
-                                tp->t_stime = ddi_get_lbolt();
-                                thread_unlock(tp);
-
-                                nswapped--;
-                                tot_swapped_in++;
-                                num_swapped_in++;
-
-                                TRACE_2(TR_FAC_SCHED, TR_SWAPIN,
-                                    "swapin: pp %p stack_pages %lu",
-                                    pp, stack_pages);
-                                goto top;
-                        }
-                }
-                thread_unlock(tp);
-        } while ((tp = tp->t_forw) != pp->p_tlist);
-        return (num_swapped_in);
-}
-
-/*
- * Swap out lwps.  Returns nonzero on success (i.e., if at least one lwp is
- * swapped out) and 0 on failure.
- */
-static int
-swapout(proc_t *pp, uint_t *swrss, int swapflags)
-{
-        kthread_id_t tp;
-        pgcnt_t ws_pages = 0;
-        int err;
-        int swapped_lwps = 0;
-        struct as *as = pp->p_as;
-        struct cpu *cpup = CPU;
-        pri_t thread_pri;
-
-        ASSERT(MUTEX_HELD(&pp->p_lock));
-
-        if (pp->p_flag & SEXITING)
-                return (0);
-
-top:
-        tp = pp->p_tlist;
-        do {
-                klwp_t *lwp = ttolwp(tp);
-
-                /*
-                 * Swapout eligible lwps (specified by the scheduling
-                 * class) which don't have TS_DONT_SWAP set.  Set the
-                 * "intent to swap" flag (TS_SWAPENQ) on threads
-                 * which have TS_DONT_SWAP set so that they can be
-                 * swapped if and when they reach a safe point.
-                 */
-                thread_lock(tp);
-                thread_pri = CL_SWAPOUT(tp, swapflags);
-                if (thread_pri != -1) {
-                        if (tp->t_schedflag & TS_DONT_SWAP) {
-                                tp->t_schedflag |= TS_SWAPENQ;
-                                tp->t_trapret = 1;
-                                aston(tp);
-                        } else {
-                                pgcnt_t stack_pages;
-                                size_t stack_size;
-
-                                ASSERT((tp->t_schedflag &
-                                    (TS_DONT_SWAP | TS_LOAD)) == TS_LOAD);
-
-                                if (lock_try(&tp->t_lock)) {
-                                        /*
-                                         * Remove thread from the swap_queue.
-                                         */
-                                        if (tp->t_schedflag & TS_ON_SWAPQ) {
-                                                ASSERT(!(tp->t_schedflag &
-                                                    TS_SWAPENQ));
-                                                swapdeq(tp);
-                                        } else if (tp->t_state == TS_RUN)
-                                                dq_srundec(tp);
-
-                                        tp->t_schedflag &=
-                                            ~(TS_LOAD | TS_SWAPENQ);
-                                        lock_clear(&tp->t_lock);
-
-                                        /*
-                                         * Set swapout time if the thread isn't
-                                         * sleeping.
-                                         */
-                                        if (tp->t_state != TS_SLEEP)
-                                                tp->t_stime = ddi_get_lbolt();
-                                        thread_unlock(tp);
-
-                                        nswapped++;
-                                        tot_swapped_out++;
-
-                                        lwp->lwp_ru.nswap++;
-
-                                        /*
-                                         * Now drop the p_lock since the
-                                         * stack needs to pushed out.
-                                         */
-                                        mutex_exit(&pp->p_lock);
-
-                                        stack_size = swapsize(tp->t_swap);
-                                        stack_pages = btopr(stack_size);
-                                        ws_pages += stack_pages;
-                                        /* Kernel probe */
-                                        TNF_PROBE_4(swapout_lwp,
-                                            "vm swap swapout",
-                                            /* CSTYLED */,
-                                            tnf_pid, pid, pp->p_pid,
-                                            tnf_lwpid, lwpid, tp->t_tid,
-                                            tnf_kthread_id, tid, tp,
-                                            tnf_ulong, page_count,
-                                            stack_pages);
-
-                                        rw_enter(&kas.a_lock, RW_READER);
-                                        err = segkp_fault(segkp->s_as->a_hat,
-                                            segkp, tp->t_swap, stack_size,
-                                            F_SOFTUNLOCK, S_WRITE);
-                                        rw_exit(&kas.a_lock);
-
-                                        if (err) {
-                                                cmn_err(CE_PANIC,
-                                                    "swapout: segkp_fault "
-                                                    "failed err: %d", err);
-                                        }
-                                        CPU_STATS_ADDQ(cpup,
-                                            vm, pgswapout, stack_pages);
-
-                                        mutex_enter(&pp->p_lock);
-                                        pp->p_swapcnt++;
-                                        swapped_lwps++;
-                                        goto top;
-                                }
-                        }
-                }
-                thread_unlock(tp);
-        } while ((tp = tp->t_forw) != pp->p_tlist);
-
-        /*
-         * Unload address space when all lwps are swapped out.
-         */
-        if (pp->p_swapcnt == pp->p_lwpcnt) {
-                size_t as_size = 0;
-
-                /*
-                 * Avoid invoking as_swapout() if the process has
-                 * no MMU resources since pageout will eventually
-                 * steal pages belonging to this address space.  This
-                 * saves CPU cycles as the number of pages that are
-                 * potentially freed or pushed out by the segment
-                 * swapout operation is very small.
-                 */
-                if (rm_asrss(pp->p_as) != 0)
-                        as_size = as_swapout(as);
-
-                CPU_STATS_ADDQ(cpup, vm, pgswapout, btop(as_size));
-                CPU_STATS_ADDQ(cpup, vm, swapout, 1);
-                ws_pages += btop(as_size);
-
-                TRACE_2(TR_FAC_SCHED, TR_SWAPOUT,
-                    "swapout: pp %p pages_pushed %lu", pp, ws_pages);
-                /* Kernel probe */
-                TNF_PROBE_2(swapout_process, "vm swap swapout", /* CSTYLED */,
-                    tnf_pid,    pid,            pp->p_pid,
-                    tnf_ulong,  page_count,     ws_pages);
-        }
-        *swrss = ws_pages;
-        return (swapped_lwps);
-}
-
-void
-swapout_lwp(klwp_t *lwp)
-{
-        kthread_id_t tp = curthread;
-
-        ASSERT(curthread == lwptot(lwp));
-
-        /*
-         * Don't insert the thread onto the swap queue if
-         * sufficient memory is available.
-         */
-        if (avefree > desfree || avefree < desfree && freemem > desfree) {
-                thread_lock(tp);
-                tp->t_schedflag &= ~TS_SWAPENQ;
-                thread_unlock(tp);
-                return;
-        }
-
-        /*
-         * Lock the thread, then move it to the swapped queue from the
-         * onproc queue and set its state to be TS_RUN.
-         */
-        thread_lock(tp);
-        ASSERT(tp->t_state == TS_ONPROC);
-        if (tp->t_schedflag & TS_SWAPENQ) {
-                tp->t_schedflag &= ~TS_SWAPENQ;
-
-                /*
-                 * Set the state of this thread to be runnable
-                 * and move it from the onproc queue to the swap queue.
-                 */
-                disp_swapped_enq(tp);
-
-                /*
-                 * Insert the thread onto the swap queue.
-                 */
-                tp->t_link = tswap_queue;
-                tswap_queue = tp;
-                tp->t_schedflag |= TS_ON_SWAPQ;
-
-                thread_unlock_nopreempt(tp);
-
-                TRACE_1(TR_FAC_SCHED, TR_SWAPOUT_LWP, "swapout_lwp:%x", lwp);
-
-                swtch();
-        } else {
-                thread_unlock(tp);
-        }
-}
-
-/*
- * Swap all threads on the swap queue.
- */
-static void
-process_swap_queue(void)
-{
-        kthread_id_t tp;
-        uint_t ws_pages;
-        proc_t *pp;
-        struct cpu *cpup = CPU;
-        klwp_t *lwp;
-        int err;
-
-        if (tswap_queue == NULL)
-                return;
-
-        /*
-         * Acquire the "swapped_lock" which locks the swap queue,
-         * and unload the stacks of all threads on it.
-         */
-        disp_lock_enter(&swapped_lock);
-        while ((tp = tswap_queue) != NULL) {
-                pgcnt_t stack_pages;
-                size_t stack_size;
-
-                tswap_queue = tp->t_link;
-                tp->t_link = NULL;
-
-                /*
-                 * Drop the "dispatcher lock" before acquiring "t_lock"
-                 * to avoid spinning on it since the thread at the front
-                 * of the swap queue could be pinned before giving up
-                 * its "t_lock" in resume.
-                 */
-                disp_lock_exit(&swapped_lock);
-                lock_set(&tp->t_lock);
-
-                /*
-                 * Now, re-acquire the "swapped_lock".  Acquiring this lock
-                 * results in locking the thread since its dispatcher lock
-                 * (t_lockp) is the "swapped_lock".
-                 */
-                disp_lock_enter(&swapped_lock);
-                ASSERT(tp->t_state == TS_RUN);
-                ASSERT(tp->t_schedflag & (TS_LOAD | TS_ON_SWAPQ));
-
-                tp->t_schedflag &= ~(TS_LOAD | TS_ON_SWAPQ);
-                tp->t_stime = ddi_get_lbolt();          /* swapout time */
-                disp_lock_exit(&swapped_lock);
-                lock_clear(&tp->t_lock);
-
-                lwp = ttolwp(tp);
-                lwp->lwp_ru.nswap++;
-
-                pp = ttoproc(tp);
-                stack_size = swapsize(tp->t_swap);
-                stack_pages = btopr(stack_size);
-
-                /* Kernel probe */
-                TNF_PROBE_4(swapout_lwp, "vm swap swapout", /* CSTYLED */,
-                    tnf_pid,            pid,            pp->p_pid,
-                    tnf_lwpid,          lwpid,          tp->t_tid,
-                    tnf_kthread_id,     tid,            tp,
-                    tnf_ulong,          page_count,     stack_pages);
-
-                rw_enter(&kas.a_lock, RW_READER);
-                err = segkp_fault(segkp->s_as->a_hat, segkp, tp->t_swap,
-                    stack_size, F_SOFTUNLOCK, S_WRITE);
-                rw_exit(&kas.a_lock);
-
-                if (err) {
-                        cmn_err(CE_PANIC,
-                        "process_swap_list: segkp_fault failed err: %d", err);
-                }
-                CPU_STATS_ADDQ(cpup, vm, pgswapout, stack_pages);
-
-                nswapped++;
-                tot_swapped_out++;
-                swapqswap++;
-
-                /*
-                 * Don't need p_lock since the swapper is the only
-                 * thread which increments/decrements p_swapcnt and p_swrss.
-                 */
-                ws_pages = stack_pages;
-                pp->p_swapcnt++;
-
-                TRACE_1(TR_FAC_SCHED, TR_SWAPQ_LWP, "swaplist: pp %p", pp);
-
-                /*
-                 * Unload address space when all lwps are swapped out.
-                 */
-                if (pp->p_swapcnt == pp->p_lwpcnt) {
-                        size_t as_size = 0;
-
-                        if (rm_asrss(pp->p_as) != 0)
-                                as_size = as_swapout(pp->p_as);
-
-                        CPU_STATS_ADDQ(cpup, vm, pgswapout,
-                            btop(as_size));
-                        CPU_STATS_ADDQ(cpup, vm, swapout, 1);
-
-                        ws_pages += btop(as_size);
-
-                        TRACE_2(TR_FAC_SCHED, TR_SWAPQ_PROC,
-                            "swaplist_proc: pp %p pages_pushed: %lu",
-                            pp, ws_pages);
-                        /* Kernel probe */
-                        TNF_PROBE_2(swapout_process, "vm swap swapout",
-                            /* CSTYLED */,
-                            tnf_pid,    pid,            pp->p_pid,
-                            tnf_ulong,  page_count,     ws_pages);
-                }
-                pp->p_swrss += ws_pages;
-                disp_lock_enter(&swapped_lock);
         }
-        disp_lock_exit(&swapped_lock);
 }