summaryrefslogtreecommitdiffstats
path: root/sys/vm
diff options
context:
space:
mode:
authorkib <kib@FreeBSD.org>2017-11-10 13:17:40 +0000
committerkib <kib@FreeBSD.org>2017-11-10 13:17:40 +0000
commite84aae2948262ee900a4736a9f92bdf4c5196981 (patch)
tree01aeb25eedaa49fdcd3dbb1212d888208b05dada /sys/vm
parent7094f779ead5c13e62afa73a8bd071b41797e1a7 (diff)
downloadFreeBSD-src-e84aae2948262ee900a4736a9f92bdf4c5196981.zip
FreeBSD-src-e84aae2948262ee900a4736a9f92bdf4c5196981.tar.gz
MFC r324795:
Move swapout code into vm/vm_swapout.c.
Diffstat (limited to 'sys/vm')
-rw-r--r--sys/vm/vm_extern.h1
-rw-r--r--sys/vm/vm_glue.c501
-rw-r--r--sys/vm/vm_pageout.c395
-rw-r--r--sys/vm/vm_pageout.h9
-rw-r--r--sys/vm/vm_swapout.c975
-rw-r--r--sys/vm/vm_swapout_dummy.c122
6 files changed, 1104 insertions, 899 deletions
diff --git a/sys/vm/vm_extern.h b/sys/vm/vm_extern.h
index 0489b6e..8e55273 100644
--- a/sys/vm/vm_extern.h
+++ b/sys/vm/vm_extern.h
@@ -71,7 +71,6 @@ void kmem_init(vm_offset_t, vm_offset_t);
void kmem_init_zero_region(void);
void kmeminit(void);
-void swapout_procs(int);
int kernacc(void *, int, int);
int useracc(void *, int, int);
int vm_fault(vm_map_t, vm_offset_t, vm_prot_t, int);
diff --git a/sys/vm/vm_glue.c b/sys/vm/vm_glue.c
index 941e7e8..14ec78a 100644
--- a/sys/vm/vm_glue.c
+++ b/sys/vm/vm_glue.c
@@ -101,13 +101,6 @@ __FBSDID("$FreeBSD$");
#include <machine/cpu.h>
-#ifndef NO_SWAPPING
-static int swapout(struct proc *);
-static void swapclear(struct proc *);
-static void vm_thread_swapin(struct thread *td);
-static void vm_thread_swapout(struct thread *td);
-#endif
-
/*
* MPSAFE
*
@@ -308,10 +301,6 @@ SYSCTL_INT(_vm, OID_AUTO, kstack_cache_size, CTLFLAG_RW, &kstack_cache_size, 0,
SYSCTL_INT(_vm, OID_AUTO, kstacks, CTLFLAG_RD, &kstacks, 0,
"");
-#ifndef KSTACK_MAX_PAGES
-#define KSTACK_MAX_PAGES 32
-#endif
-
/*
* Create the kernel stack (including pcb for i386) for a new thread.
* This routine directly affects the fork perf for a process and
@@ -527,79 +516,6 @@ intr_prof_stack_use(struct thread *td, struct trapframe *frame)
}
#endif /* KSTACK_USAGE_PROF */
-#ifndef NO_SWAPPING
-/*
- * Allow a thread's kernel stack to be paged out.
- */
-static void
-vm_thread_swapout(struct thread *td)
-{
- vm_object_t ksobj;
- vm_page_t m;
- int i, pages;
-
- cpu_thread_swapout(td);
- pages = td->td_kstack_pages;
- ksobj = td->td_kstack_obj;
- pmap_qremove(td->td_kstack, pages);
- VM_OBJECT_WLOCK(ksobj);
- for (i = 0; i < pages; i++) {
- m = vm_page_lookup(ksobj, i);
- if (m == NULL)
- panic("vm_thread_swapout: kstack already missing?");
- vm_page_dirty(m);
- vm_page_lock(m);
- vm_page_unwire(m, PQ_INACTIVE);
- vm_page_unlock(m);
- }
- VM_OBJECT_WUNLOCK(ksobj);
-}
-
-/*
- * Bring the kernel stack for a specified thread back in.
- */
-static void
-vm_thread_swapin(struct thread *td)
-{
- vm_object_t ksobj;
- vm_page_t ma[KSTACK_MAX_PAGES];
- int pages;
-
- pages = td->td_kstack_pages;
- ksobj = td->td_kstack_obj;
- VM_OBJECT_WLOCK(ksobj);
- (void)vm_page_grab_pages(ksobj, 0, VM_ALLOC_NORMAL | VM_ALLOC_WIRED, ma,
- pages);
- for (int i = 0; i < pages;) {
- int j, a, count, rv;
-
- vm_page_assert_xbusied(ma[i]);
- if (ma[i]->valid == VM_PAGE_BITS_ALL) {
- vm_page_xunbusy(ma[i]);
- i++;
- continue;
- }
- vm_object_pip_add(ksobj, 1);
- for (j = i + 1; j < pages; j++)
- if (ma[j]->valid == VM_PAGE_BITS_ALL)
- break;
- rv = vm_pager_has_page(ksobj, ma[i]->pindex, NULL, &a);
- KASSERT(rv == 1, ("%s: missing page %p", __func__, ma[i]));
- count = min(a + 1, j - i);
- rv = vm_pager_get_pages(ksobj, ma + i, count, NULL, NULL);
- KASSERT(rv == VM_PAGER_OK, ("%s: cannot get kstack for proc %d",
- __func__, td->td_proc->p_pid));
- vm_object_pip_wakeup(ksobj);
- for (j = i; j < i + count; j++)
- vm_page_xunbusy(ma[j]);
- i += count;
- }
- VM_OBJECT_WUNLOCK(ksobj);
- pmap_qenter(td->td_kstack, ma, pages);
- cpu_thread_swapin(td);
-}
-#endif /* !NO_SWAPPING */
-
/*
* Implement fork's actions on an address space.
* Here we arrange for the address space to be copied or referenced,
@@ -673,425 +589,8 @@ vm_waitproc(p)
}
void
-faultin(p)
- struct proc *p;
-{
-#ifdef NO_SWAPPING
-
- PROC_LOCK_ASSERT(p, MA_OWNED);
- if ((p->p_flag & P_INMEM) == 0)
- panic("faultin: proc swapped out with NO_SWAPPING!");
-#else /* !NO_SWAPPING */
- struct thread *td;
-
- PROC_LOCK_ASSERT(p, MA_OWNED);
- /*
- * If another process is swapping in this process,
- * just wait until it finishes.
- */
- if (p->p_flag & P_SWAPPINGIN) {
- while (p->p_flag & P_SWAPPINGIN)
- msleep(&p->p_flag, &p->p_mtx, PVM, "faultin", 0);
- return;
- }
- if ((p->p_flag & P_INMEM) == 0) {
- /*
- * Don't let another thread swap process p out while we are
- * busy swapping it in.
- */
- ++p->p_lock;
- p->p_flag |= P_SWAPPINGIN;
- PROC_UNLOCK(p);
-
- /*
- * We hold no lock here because the list of threads
- * can not change while all threads in the process are
- * swapped out.
- */
- FOREACH_THREAD_IN_PROC(p, td)
- vm_thread_swapin(td);
- PROC_LOCK(p);
- swapclear(p);
- p->p_swtick = ticks;
-
- wakeup(&p->p_flag);
-
- /* Allow other threads to swap p out now. */
- --p->p_lock;
- }
-#endif /* NO_SWAPPING */
-}
-
-/*
- * This swapin algorithm attempts to swap-in processes only if there
- * is enough space for them. Of course, if a process waits for a long
- * time, it will be swapped in anyway.
- */
-void
-swapper(void)
-{
- struct proc *p;
- struct thread *td;
- struct proc *pp;
- int slptime;
- int swtime;
- int ppri;
- int pri;
-
-loop:
- if (vm_page_count_min()) {
- VM_WAIT;
- goto loop;
- }
-
- pp = NULL;
- ppri = INT_MIN;
- sx_slock(&allproc_lock);
- FOREACH_PROC_IN_SYSTEM(p) {
- PROC_LOCK(p);
- if (p->p_state == PRS_NEW ||
- p->p_flag & (P_SWAPPINGOUT | P_SWAPPINGIN | P_INMEM)) {
- PROC_UNLOCK(p);
- continue;
- }
- swtime = (ticks - p->p_swtick) / hz;
- FOREACH_THREAD_IN_PROC(p, td) {
- /*
- * An otherwise runnable thread of a process
- * swapped out has only the TDI_SWAPPED bit set.
- *
- */
- thread_lock(td);
- if (td->td_inhibitors == TDI_SWAPPED) {
- slptime = (ticks - td->td_slptick) / hz;
- pri = swtime + slptime;
- if ((td->td_flags & TDF_SWAPINREQ) == 0)
- pri -= p->p_nice * 8;
- /*
- * if this thread is higher priority
- * and there is enough space, then select
- * this process instead of the previous
- * selection.
- */
- if (pri > ppri) {
- pp = p;
- ppri = pri;
- }
- }
- thread_unlock(td);
- }
- PROC_UNLOCK(p);
- }
- sx_sunlock(&allproc_lock);
-
- /*
- * Nothing to do, back to sleep.
- */
- if ((p = pp) == NULL) {
- tsleep(&proc0, PVM, "swapin", MAXSLP * hz / 2);
- goto loop;
- }
- PROC_LOCK(p);
-
- /*
- * Another process may be bringing or may have already
- * brought this process in while we traverse all threads.
- * Or, this process may even be being swapped out again.
- */
- if (p->p_flag & (P_INMEM | P_SWAPPINGOUT | P_SWAPPINGIN)) {
- PROC_UNLOCK(p);
- goto loop;
- }
-
- /*
- * We would like to bring someone in. (only if there is space).
- * [What checks the space? ]
- */
- faultin(p);
- PROC_UNLOCK(p);
- goto loop;
-}
-
-void
kick_proc0(void)
{
wakeup(&proc0);
}
-
-#ifndef NO_SWAPPING
-
-/*
- * Swap_idle_threshold1 is the guaranteed swapped in time for a process
- */
-static int swap_idle_threshold1 = 2;
-SYSCTL_INT(_vm, OID_AUTO, swap_idle_threshold1, CTLFLAG_RW,
- &swap_idle_threshold1, 0, "Guaranteed swapped in time for a process");
-
-/*
- * Swap_idle_threshold2 is the time that a process can be idle before
- * it will be swapped out, if idle swapping is enabled.
- */
-static int swap_idle_threshold2 = 10;
-SYSCTL_INT(_vm, OID_AUTO, swap_idle_threshold2, CTLFLAG_RW,
- &swap_idle_threshold2, 0, "Time before a process will be swapped out");
-
-/*
- * First, if any processes have been sleeping or stopped for at least
- * "swap_idle_threshold1" seconds, they are swapped out. If, however,
- * no such processes exist, then the longest-sleeping or stopped
- * process is swapped out. Finally, and only as a last resort, if
- * there are no sleeping or stopped processes, the longest-resident
- * process is swapped out.
- */
-void
-swapout_procs(action)
-int action;
-{
- struct proc *p;
- struct thread *td;
- int didswap = 0;
-
-retry:
- sx_slock(&allproc_lock);
- FOREACH_PROC_IN_SYSTEM(p) {
- struct vmspace *vm;
- int minslptime = 100000;
- int slptime;
-
- PROC_LOCK(p);
- /*
- * Watch out for a process in
- * creation. It may have no
- * address space or lock yet.
- */
- if (p->p_state == PRS_NEW) {
- PROC_UNLOCK(p);
- continue;
- }
- /*
- * An aio daemon switches its
- * address space while running.
- * Perform a quick check whether
- * a process has P_SYSTEM.
- * Filter out exiting processes.
- */
- if ((p->p_flag & (P_SYSTEM | P_WEXIT)) != 0) {
- PROC_UNLOCK(p);
- continue;
- }
- _PHOLD_LITE(p);
- PROC_UNLOCK(p);
- sx_sunlock(&allproc_lock);
-
- /*
- * Do not swapout a process that
- * is waiting for VM data
- * structures as there is a possible
- * deadlock. Test this first as
- * this may block.
- *
- * Lock the map until swapout
- * finishes, or a thread of this
- * process may attempt to alter
- * the map.
- */
- vm = vmspace_acquire_ref(p);
- if (vm == NULL)
- goto nextproc2;
- if (!vm_map_trylock(&vm->vm_map))
- goto nextproc1;
-
- PROC_LOCK(p);
- if (p->p_lock != 1 || (p->p_flag & (P_STOPPED_SINGLE |
- P_TRACED | P_SYSTEM)) != 0)
- goto nextproc;
-
- /*
- * only aiod changes vmspace, however it will be
- * skipped because of the if statement above checking
- * for P_SYSTEM
- */
- if ((p->p_flag & (P_INMEM|P_SWAPPINGOUT|P_SWAPPINGIN)) != P_INMEM)
- goto nextproc;
-
- switch (p->p_state) {
- default:
- /* Don't swap out processes in any sort
- * of 'special' state. */
- break;
-
- case PRS_NORMAL:
- /*
- * do not swapout a realtime process
- * Check all the thread groups..
- */
- FOREACH_THREAD_IN_PROC(p, td) {
- thread_lock(td);
- if (PRI_IS_REALTIME(td->td_pri_class)) {
- thread_unlock(td);
- goto nextproc;
- }
- slptime = (ticks - td->td_slptick) / hz;
- /*
- * Guarantee swap_idle_threshold1
- * time in memory.
- */
- if (slptime < swap_idle_threshold1) {
- thread_unlock(td);
- goto nextproc;
- }
-
- /*
- * Do not swapout a process if it is
- * waiting on a critical event of some
- * kind or there is a thread whose
- * pageable memory may be accessed.
- *
- * This could be refined to support
- * swapping out a thread.
- */
- if (!thread_safetoswapout(td)) {
- thread_unlock(td);
- goto nextproc;
- }
- /*
- * If the system is under memory stress,
- * or if we are swapping
- * idle processes >= swap_idle_threshold2,
- * then swap the process out.
- */
- if (((action & VM_SWAP_NORMAL) == 0) &&
- (((action & VM_SWAP_IDLE) == 0) ||
- (slptime < swap_idle_threshold2))) {
- thread_unlock(td);
- goto nextproc;
- }
-
- if (minslptime > slptime)
- minslptime = slptime;
- thread_unlock(td);
- }
-
- /*
- * If the pageout daemon didn't free enough pages,
- * or if this process is idle and the system is
- * configured to swap proactively, swap it out.
- */
- if ((action & VM_SWAP_NORMAL) ||
- ((action & VM_SWAP_IDLE) &&
- (minslptime > swap_idle_threshold2))) {
- _PRELE(p);
- if (swapout(p) == 0)
- didswap++;
- PROC_UNLOCK(p);
- vm_map_unlock(&vm->vm_map);
- vmspace_free(vm);
- goto retry;
- }
- }
-nextproc:
- PROC_UNLOCK(p);
- vm_map_unlock(&vm->vm_map);
-nextproc1:
- vmspace_free(vm);
-nextproc2:
- sx_slock(&allproc_lock);
- PRELE(p);
- }
- sx_sunlock(&allproc_lock);
- /*
- * If we swapped something out, and another process needed memory,
- * then wakeup the sched process.
- */
- if (didswap)
- wakeup(&proc0);
-}
-
-static void
-swapclear(p)
- struct proc *p;
-{
- struct thread *td;
-
- PROC_LOCK_ASSERT(p, MA_OWNED);
-
- FOREACH_THREAD_IN_PROC(p, td) {
- thread_lock(td);
- td->td_flags |= TDF_INMEM;
- td->td_flags &= ~TDF_SWAPINREQ;
- TD_CLR_SWAPPED(td);
- if (TD_CAN_RUN(td))
- if (setrunnable(td)) {
-#ifdef INVARIANTS
- /*
- * XXX: We just cleared TDI_SWAPPED
- * above and set TDF_INMEM, so this
- * should never happen.
- */
- panic("not waking up swapper");
-#endif
- }
- thread_unlock(td);
- }
- p->p_flag &= ~(P_SWAPPINGIN|P_SWAPPINGOUT);
- p->p_flag |= P_INMEM;
-}
-
-static int
-swapout(p)
- struct proc *p;
-{
- struct thread *td;
-
- PROC_LOCK_ASSERT(p, MA_OWNED);
-#if defined(SWAP_DEBUG)
- printf("swapping out %d\n", p->p_pid);
-#endif
-
- /*
- * The states of this process and its threads may have changed
- * by now. Assuming that there is only one pageout daemon thread,
- * this process should still be in memory.
- */
- KASSERT((p->p_flag & (P_INMEM|P_SWAPPINGOUT|P_SWAPPINGIN)) == P_INMEM,
- ("swapout: lost a swapout race?"));
-
- /*
- * remember the process resident count
- */
- p->p_vmspace->vm_swrss = vmspace_resident_count(p->p_vmspace);
- /*
- * Check and mark all threads before we proceed.
- */
- p->p_flag &= ~P_INMEM;
- p->p_flag |= P_SWAPPINGOUT;
- FOREACH_THREAD_IN_PROC(p, td) {
- thread_lock(td);
- if (!thread_safetoswapout(td)) {
- thread_unlock(td);
- swapclear(p);
- return (EBUSY);
- }
- td->td_flags &= ~TDF_INMEM;
- TD_SET_SWAPPED(td);
- thread_unlock(td);
- }
- td = FIRST_THREAD_IN_PROC(p);
- ++td->td_ru.ru_nswap;
- PROC_UNLOCK(p);
-
- /*
- * This list is stable because all threads are now prevented from
- * running. The list is only modified in the context of a running
- * thread in this process.
- */
- FOREACH_THREAD_IN_PROC(p, td)
- vm_thread_swapout(td);
-
- PROC_LOCK(p);
- p->p_flag &= ~P_SWAPPINGOUT;
- p->p_swtick = ticks;
- return (0);
-}
-#endif /* !NO_SWAPPING */
diff --git a/sys/vm/vm_pageout.c b/sys/vm/vm_pageout.c
index 234f832..a41ecd6 100644
--- a/sys/vm/vm_pageout.c
+++ b/sys/vm/vm_pageout.c
@@ -141,19 +141,6 @@ SYSINIT(pagedaemon, SI_SUB_KTHREAD_PAGE, SI_ORDER_SECOND, kproc_start,
SDT_PROVIDER_DEFINE(vm);
SDT_PROBE_DEFINE(vm, , , vm__lowmem_scan);
-#if !defined(NO_SWAPPING)
-/* the kernel process "vm_daemon"*/
-static void vm_daemon(void);
-static struct proc *vmproc;
-
-static struct kproc_desc vm_kp = {
- "vmdaemon",
- vm_daemon,
- &vmproc
-};
-SYSINIT(vmdaemon, SI_SUB_KTHREAD_VM, SI_ORDER_FIRST, kproc_start, &vm_kp);
-#endif
-
/* Pagedaemon activity rates, in subdivisions of one second. */
#define VM_LAUNDER_RATE 10
#define VM_INACT_SCAN_RATE 2
@@ -171,26 +158,11 @@ static enum {
VM_LAUNDRY_SHORTFALL
} vm_laundry_request = VM_LAUNDRY_IDLE;
-#if !defined(NO_SWAPPING)
-static int vm_pageout_req_swapout; /* XXX */
-static int vm_daemon_needed;
-static struct mtx vm_daemon_mtx;
-/* Allow for use by vm_pageout before vm_daemon is initialized. */
-MTX_SYSINIT(vm_daemon, &vm_daemon_mtx, "vm daemon", MTX_DEF);
-#endif
static int vm_pageout_update_period;
static int disable_swap_pageouts;
static int lowmem_period = 10;
static time_t lowmem_uptime;
-#if defined(NO_SWAPPING)
-static int vm_swap_enabled = 0;
-static int vm_swap_idle_enabled = 0;
-#else
-static int vm_swap_enabled = 1;
-static int vm_swap_idle_enabled = 0;
-#endif
-
static int vm_panic_on_oom = 0;
SYSCTL_INT(_vm, OID_AUTO, panic_on_oom,
@@ -208,18 +180,6 @@ SYSCTL_INT(_vm, OID_AUTO, pageout_update_period,
SYSCTL_INT(_vm, OID_AUTO, lowmem_period, CTLFLAG_RW, &lowmem_period, 0,
"Low memory callback period");
-#if defined(NO_SWAPPING)
-SYSCTL_INT(_vm, VM_SWAPPING_ENABLED, swap_enabled,
- CTLFLAG_RD, &vm_swap_enabled, 0, "Enable entire process swapout");
-SYSCTL_INT(_vm, OID_AUTO, swap_idle_enabled,
- CTLFLAG_RD, &vm_swap_idle_enabled, 0, "Allow swapout on idle criteria");
-#else
-SYSCTL_INT(_vm, VM_SWAPPING_ENABLED, swap_enabled,
- CTLFLAG_RW, &vm_swap_enabled, 0, "Enable entire process swapout");
-SYSCTL_INT(_vm, OID_AUTO, swap_idle_enabled,
- CTLFLAG_RW, &vm_swap_idle_enabled, 0, "Allow swapout on idle criteria");
-#endif
-
SYSCTL_INT(_vm, OID_AUTO, disable_swapspace_pageouts,
CTLFLAG_RW, &disable_swap_pageouts, 0, "Disallow swapout of dirty pages");
@@ -261,11 +221,6 @@ static boolean_t vm_pageout_fallback_object_lock(vm_page_t, vm_page_t *);
static int vm_pageout_launder(struct vm_domain *vmd, int launder,
bool in_shortfall);
static void vm_pageout_laundry_worker(void *arg);
-#if !defined(NO_SWAPPING)
-static void vm_pageout_map_deactivate_pages(vm_map_t, long);
-static void vm_pageout_object_deactivate_pages(pmap_t, vm_object_t, long);
-static void vm_req_vmdaemon(int req);
-#endif
static boolean_t vm_pageout_page_lock(vm_page_t, vm_page_t *);
/*
@@ -604,171 +559,6 @@ vm_pageout_flush(vm_page_t *mc, int count, int flags, int mreq, int *prunlen,
return (numpagedout);
}
-#if !defined(NO_SWAPPING)
-/*
- * vm_pageout_object_deactivate_pages
- *
- * Deactivate enough pages to satisfy the inactive target
- * requirements.
- *
- * The object and map must be locked.
- */
-static void
-vm_pageout_object_deactivate_pages(pmap_t pmap, vm_object_t first_object,
- long desired)
-{
- vm_object_t backing_object, object;
- vm_page_t p;
- int act_delta, remove_mode;
-
- VM_OBJECT_ASSERT_LOCKED(first_object);
- if ((first_object->flags & OBJ_FICTITIOUS) != 0)
- return;
- for (object = first_object;; object = backing_object) {
- if (pmap_resident_count(pmap) <= desired)
- goto unlock_return;
- VM_OBJECT_ASSERT_LOCKED(object);
- if ((object->flags & OBJ_UNMANAGED) != 0 ||
- object->paging_in_progress != 0)
- goto unlock_return;
-
- remove_mode = 0;
- if (object->shadow_count > 1)
- remove_mode = 1;
- /*
- * Scan the object's entire memory queue.
- */
- TAILQ_FOREACH(p, &object->memq, listq) {
- if (pmap_resident_count(pmap) <= desired)
- goto unlock_return;
- if (vm_page_busied(p))
- continue;
- PCPU_INC(cnt.v_pdpages);
- vm_page_lock(p);
- if (p->wire_count != 0 || p->hold_count != 0 ||
- !pmap_page_exists_quick(pmap, p)) {
- vm_page_unlock(p);
- continue;
- }
- act_delta = pmap_ts_referenced(p);
- if ((p->aflags & PGA_REFERENCED) != 0) {
- if (act_delta == 0)
- act_delta = 1;
- vm_page_aflag_clear(p, PGA_REFERENCED);
- }
- if (!vm_page_active(p) && act_delta != 0) {
- vm_page_activate(p);
- p->act_count += act_delta;
- } else if (vm_page_active(p)) {
- if (act_delta == 0) {
- p->act_count -= min(p->act_count,
- ACT_DECLINE);
- if (!remove_mode && p->act_count == 0) {
- pmap_remove_all(p);
- vm_page_deactivate(p);
- } else
- vm_page_requeue(p);
- } else {
- vm_page_activate(p);
- if (p->act_count < ACT_MAX -
- ACT_ADVANCE)
- p->act_count += ACT_ADVANCE;
- vm_page_requeue(p);
- }
- } else if (vm_page_inactive(p))
- pmap_remove_all(p);
- vm_page_unlock(p);
- }
- if ((backing_object = object->backing_object) == NULL)
- goto unlock_return;
- VM_OBJECT_RLOCK(backing_object);
- if (object != first_object)
- VM_OBJECT_RUNLOCK(object);
- }
-unlock_return:
- if (object != first_object)
- VM_OBJECT_RUNLOCK(object);
-}
-
-/*
- * deactivate some number of pages in a map, try to do it fairly, but
- * that is really hard to do.
- */
-static void
-vm_pageout_map_deactivate_pages(map, desired)
- vm_map_t map;
- long desired;
-{
- vm_map_entry_t tmpe;
- vm_object_t obj, bigobj;
- int nothingwired;
-
- if (!vm_map_trylock(map))
- return;
-
- bigobj = NULL;
- nothingwired = TRUE;
-
- /*
- * first, search out the biggest object, and try to free pages from
- * that.
- */
- tmpe = map->header.next;
- while (tmpe != &map->header) {
- if ((tmpe->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) {
- obj = tmpe->object.vm_object;
- if (obj != NULL && VM_OBJECT_TRYRLOCK(obj)) {
- if (obj->shadow_count <= 1 &&
- (bigobj == NULL ||
- bigobj->resident_page_count < obj->resident_page_count)) {
- if (bigobj != NULL)
- VM_OBJECT_RUNLOCK(bigobj);
- bigobj = obj;
- } else
- VM_OBJECT_RUNLOCK(obj);
- }
- }
- if (tmpe->wired_count > 0)
- nothingwired = FALSE;
- tmpe = tmpe->next;
- }
-
- if (bigobj != NULL) {
- vm_pageout_object_deactivate_pages(map->pmap, bigobj, desired);
- VM_OBJECT_RUNLOCK(bigobj);
- }
- /*
- * Next, hunt around for other pages to deactivate. We actually
- * do this search sort of wrong -- .text first is not the best idea.
- */
- tmpe = map->header.next;
- while (tmpe != &map->header) {
- if (pmap_resident_count(vm_map_pmap(map)) <= desired)
- break;
- if ((tmpe->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) {
- obj = tmpe->object.vm_object;
- if (obj != NULL) {
- VM_OBJECT_RLOCK(obj);
- vm_pageout_object_deactivate_pages(map->pmap, obj, desired);
- VM_OBJECT_RUNLOCK(obj);
- }
- }
- tmpe = tmpe->next;
- }
-
- /*
- * Remove all mappings if a process is swapped out, this will free page
- * table pages.
- */
- if (desired == 0 && nothingwired) {
- pmap_remove(vm_map_pmap(map), vm_map_min(map),
- vm_map_max(map));
- }
-
- vm_map_unlock(map);
-}
-#endif /* !defined(NO_SWAPPING) */
-
/*
* Attempt to acquire all of the necessary locks to launder a page and
* then call through the clustering layer to PUTPAGES. Wait a short
@@ -1511,14 +1301,12 @@ drop_page:
vm_pagequeue_unlock(pq);
}
-#if !defined(NO_SWAPPING)
/*
* Wakeup the swapout daemon if we didn't free the targeted number of
* pages.
*/
- if (vm_swap_enabled && page_shortage > 0)
- vm_req_vmdaemon(VM_SWAP_NORMAL);
-#endif
+ if (page_shortage > 0)
+ vm_swapout_run();
/*
* If the inactive queue scan fails repeatedly to meet its
@@ -1668,19 +1456,8 @@ drop_page:
vm_page_unlock(m);
}
vm_pagequeue_unlock(pq);
-#if !defined(NO_SWAPPING)
- /*
- * Idle process swapout -- run once per second when we are reclaiming
- * pages.
- */
- if (vm_swap_idle_enabled && pass > 0) {
- static long lsec;
- if (time_second != lsec) {
- vm_req_vmdaemon(VM_SWAP_IDLE);
- lsec = time_second;
- }
- }
-#endif
+ if (pass > 0)
+ vm_swapout_run_idle();
return (page_shortage <= 0);
}
@@ -2106,167 +1883,3 @@ pagedaemon_wakeup(void)
wakeup(&vm_pageout_wanted);
}
}
-
-#if !defined(NO_SWAPPING)
-static void
-vm_req_vmdaemon(int req)
-{
- static int lastrun = 0;
-
- mtx_lock(&vm_daemon_mtx);
- vm_pageout_req_swapout |= req;
- if ((ticks > (lastrun + hz)) || (ticks < lastrun)) {
- wakeup(&vm_daemon_needed);
- lastrun = ticks;
- }
- mtx_unlock(&vm_daemon_mtx);
-}
-
-static void
-vm_daemon(void)
-{
- struct rlimit rsslim;
- struct proc *p;
- struct thread *td;
- struct vmspace *vm;
- int breakout, swapout_flags, tryagain, attempts;
-#ifdef RACCT
- uint64_t rsize, ravailable;
-#endif
-
- while (TRUE) {
- mtx_lock(&vm_daemon_mtx);
- msleep(&vm_daemon_needed, &vm_daemon_mtx, PPAUSE, "psleep",
-#ifdef RACCT
- racct_enable ? hz : 0
-#else
- 0
-#endif
- );
- swapout_flags = vm_pageout_req_swapout;
- vm_pageout_req_swapout = 0;
- mtx_unlock(&vm_daemon_mtx);
- if (swapout_flags)
- swapout_procs(swapout_flags);
-
- /*
- * scan the processes for exceeding their rlimits or if
- * process is swapped out -- deactivate pages
- */
- tryagain = 0;
- attempts = 0;
-again:
- attempts++;
- sx_slock(&allproc_lock);
- FOREACH_PROC_IN_SYSTEM(p) {
- vm_pindex_t limit, size;
-
- /*
- * if this is a system process or if we have already
- * looked at this process, skip it.
- */
- PROC_LOCK(p);
- if (p->p_state != PRS_NORMAL ||
- p->p_flag & (P_INEXEC | P_SYSTEM | P_WEXIT)) {
- PROC_UNLOCK(p);
- continue;
- }
- /*
- * if the process is in a non-running type state,
- * don't touch it.
- */
- breakout = 0;
- FOREACH_THREAD_IN_PROC(p, td) {
- thread_lock(td);
- if (!TD_ON_RUNQ(td) &&
- !TD_IS_RUNNING(td) &&
- !TD_IS_SLEEPING(td) &&
- !TD_IS_SUSPENDED(td)) {
- thread_unlock(td);
- breakout = 1;
- break;
- }
- thread_unlock(td);
- }
- if (breakout) {
- PROC_UNLOCK(p);
- continue;
- }
- /*
- * get a limit
- */
- lim_rlimit_proc(p, RLIMIT_RSS, &rsslim);
- limit = OFF_TO_IDX(
- qmin(rsslim.rlim_cur, rsslim.rlim_max));
-
- /*
- * let processes that are swapped out really be
- * swapped out set the limit to nothing (will force a
- * swap-out.)
- */
- if ((p->p_flag & P_INMEM) == 0)
- limit = 0; /* XXX */
- vm = vmspace_acquire_ref(p);
- _PHOLD_LITE(p);
- PROC_UNLOCK(p);
- if (vm == NULL) {
- PRELE(p);
- continue;
- }
- sx_sunlock(&allproc_lock);
-
- size = vmspace_resident_count(vm);
- if (size >= limit) {
- vm_pageout_map_deactivate_pages(
- &vm->vm_map, limit);
- size = vmspace_resident_count(vm);
- }
-#ifdef RACCT
- if (racct_enable) {
- rsize = IDX_TO_OFF(size);
- PROC_LOCK(p);
- if (p->p_state == PRS_NORMAL)
- racct_set(p, RACCT_RSS, rsize);
- ravailable = racct_get_available(p, RACCT_RSS);
- PROC_UNLOCK(p);
- if (rsize > ravailable) {
- /*
- * Don't be overly aggressive; this
- * might be an innocent process,
- * and the limit could've been exceeded
- * by some memory hog. Don't try
- * to deactivate more than 1/4th
- * of process' resident set size.
- */
- if (attempts <= 8) {
- if (ravailable < rsize -
- (rsize / 4)) {
- ravailable = rsize -
- (rsize / 4);
- }
- }
- vm_pageout_map_deactivate_pages(
- &vm->vm_map,
- OFF_TO_IDX(ravailable));
- /* Update RSS usage after paging out. */
- size = vmspace_resident_count(vm);
- rsize = IDX_TO_OFF(size);
- PROC_LOCK(p);
- if (p->p_state == PRS_NORMAL)
- racct_set(p, RACCT_RSS, rsize);
- PROC_UNLOCK(p);
- if (rsize > ravailable)
- tryagain = 1;
- }
- }
-#endif
- vmspace_free(vm);
- sx_slock(&allproc_lock);
- PRELE(p);
- }
- sx_sunlock(&allproc_lock);
- if (tryagain != 0 && attempts <= 10)
- goto again;
- }
-}
-#endif /* !defined(NO_SWAPPING) */
diff --git a/sys/vm/vm_pageout.h b/sys/vm/vm_pageout.h
index b44ca2f..6f8e0e9 100644
--- a/sys/vm/vm_pageout.h
+++ b/sys/vm/vm_pageout.h
@@ -77,12 +77,6 @@ extern int vm_pageout_page_count;
extern bool vm_pageout_wanted;
extern bool vm_pages_needed;
-/*
- * Swap out requests
- */
-#define VM_SWAP_NORMAL 1
-#define VM_SWAP_IDLE 2
-
#define VM_OOM_MEM 1
#define VM_OOM_SWAPZ 2
@@ -109,5 +103,8 @@ extern void vm_waitpfault(void);
#ifdef _KERNEL
int vm_pageout_flush(vm_page_t *, int, int, int, int *, boolean_t *);
void vm_pageout_oom(int shortage);
+
+void vm_swapout_run(void);
+void vm_swapout_run_idle(void);
#endif
#endif /* _VM_VM_PAGEOUT_H_ */
diff --git a/sys/vm/vm_swapout.c b/sys/vm/vm_swapout.c
new file mode 100644
index 0000000..91b6422
--- /dev/null
+++ b/sys/vm/vm_swapout.c
@@ -0,0 +1,975 @@
+/*-
+ * Copyright (c) 1991 Regents of the University of California.
+ * All rights reserved.
+ * Copyright (c) 1994 John S. Dyson
+ * All rights reserved.
+ * Copyright (c) 1994 David Greenman
+ * All rights reserved.
+ * Copyright (c) 2005 Yahoo! Technologies Norway AS
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * The Mach Operating System project at Carnegie-Mellon University.
+ *
+ * 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.
+ *
+ * from: @(#)vm_pageout.c 7.4 (Berkeley) 5/7/91
+ *
+ *
+ * Copyright (c) 1987, 1990 Carnegie-Mellon University.
+ * All rights reserved.
+ *
+ * Authors: Avadis Tevanian, Jr., Michael Wayne Young
+ *
+ * Permission to use, copy, modify and distribute this software and
+ * its documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ *
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
+ * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ *
+ * Carnegie Mellon requests users of this software to return to
+ *
+ * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
+ * School of Computer Science
+ * Carnegie Mellon University
+ * Pittsburgh PA 15213-3890
+ *
+ * any improvements or extensions that they make and grant Carnegie the
+ * rights to redistribute these changes.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "opt_kstack_pages.h"
+#include "opt_kstack_max_pages.h"
+#include "opt_vm.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/limits.h>
+#include <sys/kernel.h>
+#include <sys/eventhandler.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/_kstack_cache.h>
+#include <sys/kthread.h>
+#include <sys/ktr.h>
+#include <sys/mount.h>
+#include <sys/racct.h>
+#include <sys/resourcevar.h>
+#include <sys/sched.h>
+#include <sys/sdt.h>
+#include <sys/signalvar.h>
+#include <sys/smp.h>
+#include <sys/time.h>
+#include <sys/vnode.h>
+#include <sys/vmmeter.h>
+#include <sys/rwlock.h>
+#include <sys/sx.h>
+#include <sys/sysctl.h>
+
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+#include <vm/vm_object.h>
+#include <vm/vm_page.h>
+#include <vm/vm_map.h>
+#include <vm/vm_pageout.h>
+#include <vm/vm_pager.h>
+#include <vm/vm_phys.h>
+#include <vm/swap_pager.h>
+#include <vm/vm_extern.h>
+#include <vm/uma.h>
+
+/* the kernel process "vm_daemon" */
+static void vm_daemon(void);
+static struct proc *vmproc;
+
+static struct kproc_desc vm_kp = {
+ "vmdaemon",
+ vm_daemon,
+ &vmproc
+};
+SYSINIT(vmdaemon, SI_SUB_KTHREAD_VM, SI_ORDER_FIRST, kproc_start, &vm_kp);
+
+static int vm_swap_enabled = 1;
+static int vm_swap_idle_enabled = 0;
+
+SYSCTL_INT(_vm, VM_SWAPPING_ENABLED, swap_enabled, CTLFLAG_RW,
+ &vm_swap_enabled, 0,
+ "Enable entire process swapout");
+SYSCTL_INT(_vm, OID_AUTO, swap_idle_enabled, CTLFLAG_RW,
+ &vm_swap_idle_enabled, 0,
+ "Allow swapout on idle criteria");
+
+/*
+ * Swap_idle_threshold1 is the guaranteed swapped in time for a process
+ */
+static int swap_idle_threshold1 = 2;
+SYSCTL_INT(_vm, OID_AUTO, swap_idle_threshold1, CTLFLAG_RW,
+ &swap_idle_threshold1, 0,
+ "Guaranteed swapped in time for a process");
+
+/*
+ * Swap_idle_threshold2 is the time that a process can be idle before
+ * it will be swapped out, if idle swapping is enabled.
+ */
+static int swap_idle_threshold2 = 10;
+SYSCTL_INT(_vm, OID_AUTO, swap_idle_threshold2, CTLFLAG_RW,
+ &swap_idle_threshold2, 0,
+ "Time before a process will be swapped out");
+
+static int vm_pageout_req_swapout; /* XXX */
+static int vm_daemon_needed;
+static struct mtx vm_daemon_mtx;
+/* Allow for use by vm_pageout before vm_daemon is initialized. */
+MTX_SYSINIT(vm_daemon, &vm_daemon_mtx, "vm daemon", MTX_DEF);
+
+static void swapclear(struct proc *);
+static int swapout(struct proc *);
+static void vm_swapout_map_deactivate_pages(vm_map_t, long);
+static void vm_swapout_object_deactivate_pages(pmap_t, vm_object_t, long);
+static void swapout_procs(int action);
+static void vm_req_vmdaemon(int req);
+static void vm_thread_swapin(struct thread *td);
+static void vm_thread_swapout(struct thread *td);
+
+/*
+ * vm_swapout_object_deactivate_pages
+ *
+ * Deactivate enough pages to satisfy the inactive target
+ * requirements.
+ *
+ * The object and map must be locked.
+ */
+static void
+vm_swapout_object_deactivate_pages(pmap_t pmap, vm_object_t first_object,
+ long desired)
+{
+ vm_object_t backing_object, object;
+ vm_page_t p;
+ int act_delta, remove_mode;
+
+ VM_OBJECT_ASSERT_LOCKED(first_object);
+ if ((first_object->flags & OBJ_FICTITIOUS) != 0)
+ return;
+ for (object = first_object;; object = backing_object) {
+ if (pmap_resident_count(pmap) <= desired)
+ goto unlock_return;
+ VM_OBJECT_ASSERT_LOCKED(object);
+ if ((object->flags & OBJ_UNMANAGED) != 0 ||
+ object->paging_in_progress != 0)
+ goto unlock_return;
+
+ remove_mode = 0;
+ if (object->shadow_count > 1)
+ remove_mode = 1;
+ /*
+ * Scan the object's entire memory queue.
+ */
+ TAILQ_FOREACH(p, &object->memq, listq) {
+ if (pmap_resident_count(pmap) <= desired)
+ goto unlock_return;
+ if (vm_page_busied(p))
+ continue;
+ PCPU_INC(cnt.v_pdpages);
+ vm_page_lock(p);
+ if (p->wire_count != 0 || p->hold_count != 0 ||
+ !pmap_page_exists_quick(pmap, p)) {
+ vm_page_unlock(p);
+ continue;
+ }
+ act_delta = pmap_ts_referenced(p);
+ if ((p->aflags & PGA_REFERENCED) != 0) {
+ if (act_delta == 0)
+ act_delta = 1;
+ vm_page_aflag_clear(p, PGA_REFERENCED);
+ }
+ if (!vm_page_active(p) && act_delta != 0) {
+ vm_page_activate(p);
+ p->act_count += act_delta;
+ } else if (vm_page_active(p)) {
+ if (act_delta == 0) {
+ p->act_count -= min(p->act_count,
+ ACT_DECLINE);
+ if (!remove_mode && p->act_count == 0) {
+ pmap_remove_all(p);
+ vm_page_deactivate(p);
+ } else
+ vm_page_requeue(p);
+ } else {
+ vm_page_activate(p);
+ if (p->act_count < ACT_MAX -
+ ACT_ADVANCE)
+ p->act_count += ACT_ADVANCE;
+ vm_page_requeue(p);
+ }
+ } else if (vm_page_inactive(p))
+ pmap_remove_all(p);
+ vm_page_unlock(p);
+ }
+ if ((backing_object = object->backing_object) == NULL)
+ goto unlock_return;
+ VM_OBJECT_RLOCK(backing_object);
+ if (object != first_object)
+ VM_OBJECT_RUNLOCK(object);
+ }
+unlock_return:
+ if (object != first_object)
+ VM_OBJECT_RUNLOCK(object);
+}
+
+/*
+ * deactivate some number of pages in a map, try to do it fairly, but
+ * that is really hard to do.
+ */
+static void
+vm_swapout_map_deactivate_pages(vm_map_t map, long desired)
+{
+ vm_map_entry_t tmpe;
+ vm_object_t obj, bigobj;
+ int nothingwired;
+
+ if (!vm_map_trylock(map))
+ return;
+
+ bigobj = NULL;
+ nothingwired = TRUE;
+
+ /*
+ * first, search out the biggest object, and try to free pages from
+ * that.
+ */
+ tmpe = map->header.next;
+ while (tmpe != &map->header) {
+ if ((tmpe->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) {
+ obj = tmpe->object.vm_object;
+ if (obj != NULL && VM_OBJECT_TRYRLOCK(obj)) {
+ if (obj->shadow_count <= 1 &&
+ (bigobj == NULL ||
+ bigobj->resident_page_count <
+ obj->resident_page_count)) {
+ if (bigobj != NULL)
+ VM_OBJECT_RUNLOCK(bigobj);
+ bigobj = obj;
+ } else
+ VM_OBJECT_RUNLOCK(obj);
+ }
+ }
+ if (tmpe->wired_count > 0)
+ nothingwired = FALSE;
+ tmpe = tmpe->next;
+ }
+
+ if (bigobj != NULL) {
+ vm_swapout_object_deactivate_pages(map->pmap, bigobj, desired);
+ VM_OBJECT_RUNLOCK(bigobj);
+ }
+ /*
+ * Next, hunt around for other pages to deactivate. We actually
+ * do this search sort of wrong -- .text first is not the best idea.
+ */
+ tmpe = map->header.next;
+ while (tmpe != &map->header) {
+ if (pmap_resident_count(vm_map_pmap(map)) <= desired)
+ break;
+ if ((tmpe->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) {
+ obj = tmpe->object.vm_object;
+ if (obj != NULL) {
+ VM_OBJECT_RLOCK(obj);
+ vm_swapout_object_deactivate_pages(map->pmap,
+ obj, desired);
+ VM_OBJECT_RUNLOCK(obj);
+ }
+ }
+ tmpe = tmpe->next;
+ }
+
+ /*
+ * Remove all mappings if a process is swapped out, this will free page
+ * table pages.
+ */
+ if (desired == 0 && nothingwired) {
+ pmap_remove(vm_map_pmap(map), vm_map_min(map),
+ vm_map_max(map));
+ }
+
+ vm_map_unlock(map);
+}
+
+/*
+ * Swap out requests
+ */
+#define VM_SWAP_NORMAL 1
+#define VM_SWAP_IDLE 2
+
+void
+vm_swapout_run(void)
+{
+
+ if (vm_swap_enabled)
+ vm_req_vmdaemon(VM_SWAP_NORMAL);
+}
+
+/*
+ * Idle process swapout -- run once per second when pagedaemons are
+ * reclaiming pages.
+ */
+void
+vm_swapout_run_idle(void)
+{
+ static long lsec;
+
+ if (!vm_swap_idle_enabled || time_second == lsec)
+ return;
+ vm_req_vmdaemon(VM_SWAP_IDLE);
+ lsec = time_second;
+}
+
+static void
+vm_req_vmdaemon(int req)
+{
+ static int lastrun = 0;
+
+ mtx_lock(&vm_daemon_mtx);
+ vm_pageout_req_swapout |= req;
+ if ((ticks > (lastrun + hz)) || (ticks < lastrun)) {
+ wakeup(&vm_daemon_needed);
+ lastrun = ticks;
+ }
+ mtx_unlock(&vm_daemon_mtx);
+}
+
+static void
+vm_daemon(void)
+{
+ struct rlimit rsslim;
+ struct proc *p;
+ struct thread *td;
+ struct vmspace *vm;
+ int breakout, swapout_flags, tryagain, attempts;
+#ifdef RACCT
+ uint64_t rsize, ravailable;
+#endif
+
+ while (TRUE) {
+ mtx_lock(&vm_daemon_mtx);
+ msleep(&vm_daemon_needed, &vm_daemon_mtx, PPAUSE, "psleep",
+#ifdef RACCT
+ racct_enable ? hz : 0
+#else
+ 0
+#endif
+ );
+ swapout_flags = vm_pageout_req_swapout;
+ vm_pageout_req_swapout = 0;
+ mtx_unlock(&vm_daemon_mtx);
+ if (swapout_flags)
+ swapout_procs(swapout_flags);
+
+ /*
+ * scan the processes for exceeding their rlimits or if
+ * process is swapped out -- deactivate pages
+ */
+ tryagain = 0;
+ attempts = 0;
+again:
+ attempts++;
+ sx_slock(&allproc_lock);
+ FOREACH_PROC_IN_SYSTEM(p) {
+ vm_pindex_t limit, size;
+
+ /*
+ * if this is a system process or if we have already
+ * looked at this process, skip it.
+ */
+ PROC_LOCK(p);
+ if (p->p_state != PRS_NORMAL ||
+ p->p_flag & (P_INEXEC | P_SYSTEM | P_WEXIT)) {
+ PROC_UNLOCK(p);
+ continue;
+ }
+ /*
+ * if the process is in a non-running type state,
+ * don't touch it.
+ */
+ breakout = 0;
+ FOREACH_THREAD_IN_PROC(p, td) {
+ thread_lock(td);
+ if (!TD_ON_RUNQ(td) &&
+ !TD_IS_RUNNING(td) &&
+ !TD_IS_SLEEPING(td) &&
+ !TD_IS_SUSPENDED(td)) {
+ thread_unlock(td);
+ breakout = 1;
+ break;
+ }
+ thread_unlock(td);
+ }
+ if (breakout) {
+ PROC_UNLOCK(p);
+ continue;
+ }
+ /*
+ * get a limit
+ */
+ lim_rlimit_proc(p, RLIMIT_RSS, &rsslim);
+ limit = OFF_TO_IDX(
+ qmin(rsslim.rlim_cur, rsslim.rlim_max));
+
+ /*
+ * let processes that are swapped out really be
+ * swapped out set the limit to nothing (will force a
+ * swap-out.)
+ */
+ if ((p->p_flag & P_INMEM) == 0)
+ limit = 0; /* XXX */
+ vm = vmspace_acquire_ref(p);
+ _PHOLD_LITE(p);
+ PROC_UNLOCK(p);
+ if (vm == NULL) {
+ PRELE(p);
+ continue;
+ }
+ sx_sunlock(&allproc_lock);
+
+ size = vmspace_resident_count(vm);
+ if (size >= limit) {
+ vm_swapout_map_deactivate_pages(
+ &vm->vm_map, limit);
+ size = vmspace_resident_count(vm);
+ }
+#ifdef RACCT
+ if (racct_enable) {
+ rsize = IDX_TO_OFF(size);
+ PROC_LOCK(p);
+ if (p->p_state == PRS_NORMAL)
+ racct_set(p, RACCT_RSS, rsize);
+ ravailable = racct_get_available(p, RACCT_RSS);
+ PROC_UNLOCK(p);
+ if (rsize > ravailable) {
+ /*
+ * Don't be overly aggressive; this
+ * might be an innocent process,
+ * and the limit could've been exceeded
+ * by some memory hog. Don't try
+ * to deactivate more than 1/4th
+ * of process' resident set size.
+ */
+ if (attempts <= 8) {
+ if (ravailable < rsize -
+ (rsize / 4)) {
+ ravailable = rsize -
+ (rsize / 4);
+ }
+ }
+ vm_swapout_map_deactivate_pages(
+ &vm->vm_map,
+ OFF_TO_IDX(ravailable));
+ /* Update RSS usage after paging out. */
+ size = vmspace_resident_count(vm);
+ rsize = IDX_TO_OFF(size);
+ PROC_LOCK(p);
+ if (p->p_state == PRS_NORMAL)
+ racct_set(p, RACCT_RSS, rsize);
+ PROC_UNLOCK(p);
+ if (rsize > ravailable)
+ tryagain = 1;
+ }
+ }
+#endif
+ vmspace_free(vm);
+ sx_slock(&allproc_lock);
+ PRELE(p);
+ }
+ sx_sunlock(&allproc_lock);
+ if (tryagain != 0 && attempts <= 10)
+ goto again;
+ }
+}
+
+/*
+ * Allow a thread's kernel stack to be paged out.
+ */
+static void
+vm_thread_swapout(struct thread *td)
+{
+ vm_object_t ksobj;
+ vm_page_t m;
+ int i, pages;
+
+ cpu_thread_swapout(td);
+ pages = td->td_kstack_pages;
+ ksobj = td->td_kstack_obj;
+ pmap_qremove(td->td_kstack, pages);
+ VM_OBJECT_WLOCK(ksobj);
+ for (i = 0; i < pages; i++) {
+ m = vm_page_lookup(ksobj, i);
+ if (m == NULL)
+ panic("vm_thread_swapout: kstack already missing?");
+ vm_page_dirty(m);
+ vm_page_lock(m);
+ vm_page_unwire(m, PQ_INACTIVE);
+ vm_page_unlock(m);
+ }
+ VM_OBJECT_WUNLOCK(ksobj);
+}
+
+/*
+ * Bring the kernel stack for a specified thread back in.
+ */
+static void
+vm_thread_swapin(struct thread *td)
+{
+ vm_object_t ksobj;
+ vm_page_t ma[KSTACK_MAX_PAGES];
+ int pages;
+
+ pages = td->td_kstack_pages;
+ ksobj = td->td_kstack_obj;
+ VM_OBJECT_WLOCK(ksobj);
+ (void)vm_page_grab_pages(ksobj, 0, VM_ALLOC_NORMAL | VM_ALLOC_WIRED, ma,
+ pages);
+ for (int i = 0; i < pages;) {
+ int j, a, count, rv;
+
+ vm_page_assert_xbusied(ma[i]);
+ if (ma[i]->valid == VM_PAGE_BITS_ALL) {
+ vm_page_xunbusy(ma[i]);
+ i++;
+ continue;
+ }
+ vm_object_pip_add(ksobj, 1);
+ for (j = i + 1; j < pages; j++)
+ if (ma[j]->valid == VM_PAGE_BITS_ALL)
+ break;
+ rv = vm_pager_has_page(ksobj, ma[i]->pindex, NULL, &a);
+ KASSERT(rv == 1, ("%s: missing page %p", __func__, ma[i]));
+ count = min(a + 1, j - i);
+ rv = vm_pager_get_pages(ksobj, ma + i, count, NULL, NULL);
+ KASSERT(rv == VM_PAGER_OK, ("%s: cannot get kstack for proc %d",
+ __func__, td->td_proc->p_pid));
+ vm_object_pip_wakeup(ksobj);
+ for (j = i; j < i + count; j++)
+ vm_page_xunbusy(ma[j]);
+ i += count;
+ }
+ VM_OBJECT_WUNLOCK(ksobj);
+ pmap_qenter(td->td_kstack, ma, pages);
+ cpu_thread_swapin(td);
+}
+
+void
+faultin(struct proc *p)
+{
+ struct thread *td;
+
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+ /*
+ * If another process is swapping in this process,
+ * just wait until it finishes.
+ */
+ if (p->p_flag & P_SWAPPINGIN) {
+ while (p->p_flag & P_SWAPPINGIN)
+ msleep(&p->p_flag, &p->p_mtx, PVM, "faultin", 0);
+ return;
+ }
+ if ((p->p_flag & P_INMEM) == 0) {
+ /*
+ * Don't let another thread swap process p out while we are
+ * busy swapping it in.
+ */
+ ++p->p_lock;
+ p->p_flag |= P_SWAPPINGIN;
+ PROC_UNLOCK(p);
+
+ /*
+ * We hold no lock here because the list of threads
+ * can not change while all threads in the process are
+ * swapped out.
+ */
+ FOREACH_THREAD_IN_PROC(p, td)
+ vm_thread_swapin(td);
+ PROC_LOCK(p);
+ swapclear(p);
+ p->p_swtick = ticks;
+
+ wakeup(&p->p_flag);
+
+ /* Allow other threads to swap p out now. */
+ --p->p_lock;
+ }
+}
+
+/*
+ * This swapin algorithm attempts to swap-in processes only if there
+ * is enough space for them. Of course, if a process waits for a long
+ * time, it will be swapped in anyway.
+ */
+void
+swapper(void)
+{
+ struct proc *p;
+ struct thread *td;
+ struct proc *pp;
+ int slptime;
+ int swtime;
+ int ppri;
+ int pri;
+
+loop:
+ if (vm_page_count_min()) {
+ VM_WAIT;
+ goto loop;
+ }
+
+ pp = NULL;
+ ppri = INT_MIN;
+ sx_slock(&allproc_lock);
+ FOREACH_PROC_IN_SYSTEM(p) {
+ PROC_LOCK(p);
+ if (p->p_state == PRS_NEW ||
+ p->p_flag & (P_SWAPPINGOUT | P_SWAPPINGIN | P_INMEM)) {
+ PROC_UNLOCK(p);
+ continue;
+ }
+ swtime = (ticks - p->p_swtick) / hz;
+ FOREACH_THREAD_IN_PROC(p, td) {
+ /*
+ * An otherwise runnable thread of a process
+ * swapped out has only the TDI_SWAPPED bit set.
+ */
+ thread_lock(td);
+ if (td->td_inhibitors == TDI_SWAPPED) {
+ slptime = (ticks - td->td_slptick) / hz;
+ pri = swtime + slptime;
+ if ((td->td_flags & TDF_SWAPINREQ) == 0)
+ pri -= p->p_nice * 8;
+ /*
+ * if this thread is higher priority
+ * and there is enough space, then select
+ * this process instead of the previous
+ * selection.
+ */
+ if (pri > ppri) {
+ pp = p;
+ ppri = pri;
+ }
+ }
+ thread_unlock(td);
+ }
+ PROC_UNLOCK(p);
+ }
+ sx_sunlock(&allproc_lock);
+
+ /*
+ * Nothing to do, back to sleep.
+ */
+ if ((p = pp) == NULL) {
+ tsleep(&proc0, PVM, "swapin", MAXSLP * hz / 2);
+ goto loop;
+ }
+ PROC_LOCK(p);
+
+ /*
+ * Another process may be bringing or may have already
+ * brought this process in while we traverse all threads.
+ * Or, this process may even be being swapped out again.
+ */
+ if (p->p_flag & (P_INMEM | P_SWAPPINGOUT | P_SWAPPINGIN)) {
+ PROC_UNLOCK(p);
+ goto loop;
+ }
+
+ /*
+ * We would like to bring someone in. (only if there is space).
+ * [What checks the space? ]
+ */
+ faultin(p);
+ PROC_UNLOCK(p);
+ goto loop;
+}
+
+/*
+ * First, if any processes have been sleeping or stopped for at least
+ * "swap_idle_threshold1" seconds, they are swapped out. If, however,
+ * no such processes exist, then the longest-sleeping or stopped
+ * process is swapped out. Finally, and only as a last resort, if
+ * there are no sleeping or stopped processes, the longest-resident
+ * process is swapped out.
+ */
+static void
+swapout_procs(int action)
+{
+ struct proc *p;
+ struct thread *td;
+ int didswap = 0;
+
+retry:
+ sx_slock(&allproc_lock);
+ FOREACH_PROC_IN_SYSTEM(p) {
+ struct vmspace *vm;
+ int minslptime = 100000;
+ int slptime;
+
+ PROC_LOCK(p);
+ /*
+ * Watch out for a process in
+ * creation. It may have no
+ * address space or lock yet.
+ */
+ if (p->p_state == PRS_NEW) {
+ PROC_UNLOCK(p);
+ continue;
+ }
+ /*
+ * An aio daemon switches its
+ * address space while running.
+ * Perform a quick check whether
+ * a process has P_SYSTEM.
+ * Filter out exiting processes.
+ */
+ if ((p->p_flag & (P_SYSTEM | P_WEXIT)) != 0) {
+ PROC_UNLOCK(p);
+ continue;
+ }
+ _PHOLD_LITE(p);
+ PROC_UNLOCK(p);
+ sx_sunlock(&allproc_lock);
+
+ /*
+ * Do not swapout a process that
+ * is waiting for VM data
+ * structures as there is a possible
+ * deadlock. Test this first as
+ * this may block.
+ *
+ * Lock the map until swapout
+ * finishes, or a thread of this
+ * process may attempt to alter
+ * the map.
+ */
+ vm = vmspace_acquire_ref(p);
+ if (vm == NULL)
+ goto nextproc2;
+ if (!vm_map_trylock(&vm->vm_map))
+ goto nextproc1;
+
+ PROC_LOCK(p);
+ if (p->p_lock != 1 || (p->p_flag & (P_STOPPED_SINGLE |
+ P_TRACED | P_SYSTEM)) != 0)
+ goto nextproc;
+
+ /*
+ * only aiod changes vmspace, however it will be
+ * skipped because of the if statement above checking
+ * for P_SYSTEM
+ */
+ if ((p->p_flag & (P_INMEM|P_SWAPPINGOUT|P_SWAPPINGIN)) != P_INMEM)
+ goto nextproc;
+
+ switch (p->p_state) {
+ default:
+ /* Don't swap out processes in any sort
+ * of 'special' state. */
+ break;
+
+ case PRS_NORMAL:
+ /*
+ * do not swapout a realtime process
+ * Check all the thread groups..
+ */
+ FOREACH_THREAD_IN_PROC(p, td) {
+ thread_lock(td);
+ if (PRI_IS_REALTIME(td->td_pri_class)) {
+ thread_unlock(td);
+ goto nextproc;
+ }
+ slptime = (ticks - td->td_slptick) / hz;
+ /*
+ * Guarantee swap_idle_threshold1
+ * time in memory.
+ */
+ if (slptime < swap_idle_threshold1) {
+ thread_unlock(td);
+ goto nextproc;
+ }
+
+ /*
+ * Do not swapout a process if it is
+ * waiting on a critical event of some
+ * kind or there is a thread whose
+ * pageable memory may be accessed.
+ *
+ * This could be refined to support
+ * swapping out a thread.
+ */
+ if (!thread_safetoswapout(td)) {
+ thread_unlock(td);
+ goto nextproc;
+ }
+ /*
+ * If the system is under memory stress,
+ * or if we are swapping
+ * idle processes >= swap_idle_threshold2,
+ * then swap the process out.
+ */
+ if (((action & VM_SWAP_NORMAL) == 0) &&
+ (((action & VM_SWAP_IDLE) == 0) ||
+ (slptime < swap_idle_threshold2))) {
+ thread_unlock(td);
+ goto nextproc;
+ }
+
+ if (minslptime > slptime)
+ minslptime = slptime;
+ thread_unlock(td);
+ }
+
+ /*
+ * If the pageout daemon didn't free enough pages,
+ * or if this process is idle and the system is
+ * configured to swap proactively, swap it out.
+ */
+ if ((action & VM_SWAP_NORMAL) ||
+ ((action & VM_SWAP_IDLE) &&
+ (minslptime > swap_idle_threshold2))) {
+ _PRELE(p);
+ if (swapout(p) == 0)
+ didswap++;
+ PROC_UNLOCK(p);
+ vm_map_unlock(&vm->vm_map);
+ vmspace_free(vm);
+ goto retry;
+ }
+ }
+nextproc:
+ PROC_UNLOCK(p);
+ vm_map_unlock(&vm->vm_map);
+nextproc1:
+ vmspace_free(vm);
+nextproc2:
+ sx_slock(&allproc_lock);
+ PRELE(p);
+ }
+ sx_sunlock(&allproc_lock);
+ /*
+ * If we swapped something out, and another process needed memory,
+ * then wakeup the sched process.
+ */
+ if (didswap)
+ wakeup(&proc0);
+}
+
+static void
+swapclear(struct proc *p)
+{
+ struct thread *td;
+
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+
+ FOREACH_THREAD_IN_PROC(p, td) {
+ thread_lock(td);
+ td->td_flags |= TDF_INMEM;
+ td->td_flags &= ~TDF_SWAPINREQ;
+ TD_CLR_SWAPPED(td);
+ if (TD_CAN_RUN(td))
+ if (setrunnable(td)) {
+#ifdef INVARIANTS
+ /*
+ * XXX: We just cleared TDI_SWAPPED
+ * above and set TDF_INMEM, so this
+ * should never happen.
+ */
+ panic("not waking up swapper");
+#endif
+ }
+ thread_unlock(td);
+ }
+ p->p_flag &= ~(P_SWAPPINGIN | P_SWAPPINGOUT);
+ p->p_flag |= P_INMEM;
+}
+
+static int
+swapout(struct proc *p)
+{
+ struct thread *td;
+
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+
+ /*
+ * The states of this process and its threads may have changed
+ * by now. Assuming that there is only one pageout daemon thread,
+ * this process should still be in memory.
+ */
+ KASSERT((p->p_flag & (P_INMEM | P_SWAPPINGOUT | P_SWAPPINGIN)) ==
+ P_INMEM, ("swapout: lost a swapout race?"));
+
+ /*
+ * remember the process resident count
+ */
+ p->p_vmspace->vm_swrss = vmspace_resident_count(p->p_vmspace);
+ /*
+ * Check and mark all threads before we proceed.
+ */
+ p->p_flag &= ~P_INMEM;
+ p->p_flag |= P_SWAPPINGOUT;
+ FOREACH_THREAD_IN_PROC(p, td) {
+ thread_lock(td);
+ if (!thread_safetoswapout(td)) {
+ thread_unlock(td);
+ swapclear(p);
+ return (EBUSY);
+ }
+ td->td_flags &= ~TDF_INMEM;
+ TD_SET_SWAPPED(td);
+ thread_unlock(td);
+ }
+ td = FIRST_THREAD_IN_PROC(p);
+ ++td->td_ru.ru_nswap;
+ PROC_UNLOCK(p);
+
+ /*
+ * This list is stable because all threads are now prevented from
+ * running. The list is only modified in the context of a running
+ * thread in this process.
+ */
+ FOREACH_THREAD_IN_PROC(p, td)
+ vm_thread_swapout(td);
+
+ PROC_LOCK(p);
+ p->p_flag &= ~P_SWAPPINGOUT;
+ p->p_swtick = ticks;
+ return (0);
+}
diff --git a/sys/vm/vm_swapout_dummy.c b/sys/vm/vm_swapout_dummy.c
new file mode 100644
index 0000000..9cdfcb8
--- /dev/null
+++ b/sys/vm/vm_swapout_dummy.c
@@ -0,0 +1,122 @@
+/*-
+ * Copyright (c) 1991 Regents of the University of California.
+ * All rights reserved.
+ * Copyright (c) 1994 John S. Dyson
+ * All rights reserved.
+ * Copyright (c) 1994 David Greenman
+ * All rights reserved.
+ * Copyright (c) 2005 Yahoo! Technologies Norway AS
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * The Mach Operating System project at Carnegie-Mellon University.
+ *
+ * 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.
+ *
+ * from: @(#)vm_pageout.c 7.4 (Berkeley) 5/7/91
+ *
+ *
+ * Copyright (c) 1987, 1990 Carnegie-Mellon University.
+ * All rights reserved.
+ *
+ * Authors: Avadis Tevanian, Jr., Michael Wayne Young
+ *
+ * Permission to use, copy, modify and distribute this software and
+ * its documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ *
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
+ * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ *
+ * Carnegie Mellon requests users of this software to return to
+ *
+ * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
+ * School of Computer Science
+ * Carnegie Mellon University
+ * Pittsburgh PA 15213-3890
+ *
+ * any improvements or extensions that they make and grant Carnegie the
+ * rights to redistribute these changes.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/sysctl.h>
+#include <sys/vmmeter.h>
+
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+#include <vm/vm_pageout.h>
+
+static int vm_swap_enabled = 0;
+SYSCTL_INT(_vm, VM_SWAPPING_ENABLED, swap_enabled, CTLFLAG_RD,
+ &vm_swap_enabled, 0,
+ "Enable entire process swapout");
+
+static int vm_swap_idle_enabled = 0;
+SYSCTL_INT(_vm, OID_AUTO, swap_idle_enabled, CTLFLAG_RD,
+ &vm_swap_idle_enabled, 0,
+ "Allow swapout on idle criteria");
+
+void
+vm_swapout_run(void)
+{
+}
+
+void
+vm_swapout_run_idle(void)
+{
+}
+
+void
+faultin(struct proc *p)
+{
+
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+ if ((p->p_flag & P_INMEM) == 0)
+ panic("faultin: proc %p swapped out with NO_SWAPPING", p);
+}
+
+void
+swapper(void)
+{
+
+ for (;;)
+ tsleep(&proc0, PVM, "swapin", MAXSLP * hz);
+}
OpenPOWER on IntegriCloud