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Index: sys/amd64/include/vmparam.h
===================================================================
--- sys/amd64/include/vmparam.h
+++ sys/amd64/include/vmparam.h
@@ -227,4 +227,10 @@
#define ZERO_REGION_SIZE (2 * 1024 * 1024) /* 2MB */
+/*
+ * Use a fairly large batch size since we expect amd64 systems to have lots of
+ * memory.
+ */
+#define VM_BATCHQUEUE_SIZE 31
+
#endif /* _MACHINE_VMPARAM_H_ */
Index: sys/kern/subr_witness.c
===================================================================
--- sys/kern/subr_witness.c
+++ sys/kern/subr_witness.c
@@ -603,7 +603,6 @@
* CDEV
*/
{ "vm map (system)", &lock_class_mtx_sleep },
- { "vm pagequeue", &lock_class_mtx_sleep },
{ "vnode interlock", &lock_class_mtx_sleep },
{ "cdev", &lock_class_mtx_sleep },
{ NULL, NULL },
@@ -613,11 +612,11 @@
{ "vm map (user)", &lock_class_sx },
{ "vm object", &lock_class_rw },
{ "vm page", &lock_class_mtx_sleep },
- { "vm pagequeue", &lock_class_mtx_sleep },
{ "pmap pv global", &lock_class_rw },
{ "pmap", &lock_class_mtx_sleep },
{ "pmap pv list", &lock_class_rw },
{ "vm page free queue", &lock_class_mtx_sleep },
+ { "vm pagequeue", &lock_class_mtx_sleep },
{ NULL, NULL },
/*
* kqueue/VFS interaction
Index: sys/vm/vm_object.c
===================================================================
--- sys/vm/vm_object.c
+++ sys/vm/vm_object.c
@@ -720,14 +720,11 @@
vm_object_terminate_pages(vm_object_t object)
{
vm_page_t p, p_next;
- struct mtx *mtx, *mtx1;
- struct vm_pagequeue *pq, *pq1;
- int dequeued;
+ struct mtx *mtx;
VM_OBJECT_ASSERT_WLOCKED(object);
mtx = NULL;
- pq = NULL;
/*
* Free any remaining pageable pages. This also removes them from the
@@ -737,60 +734,21 @@
*/
TAILQ_FOREACH_SAFE(p, &object->memq, listq, p_next) {
vm_page_assert_unbusied(p);
- if ((object->flags & OBJ_UNMANAGED) == 0) {
+ if ((object->flags & OBJ_UNMANAGED) == 0)
/*
* vm_page_free_prep() only needs the page
* lock for managed pages.
*/
- mtx1 = vm_page_lockptr(p);
- if (mtx1 != mtx) {
- if (mtx != NULL)
- mtx_unlock(mtx);
- if (pq != NULL) {
- vm_pagequeue_cnt_add(pq, dequeued);
- vm_pagequeue_unlock(pq);
- pq = NULL;
- }
- mtx = mtx1;
- mtx_lock(mtx);
- }
- }
+ vm_page_change_lock(p, &mtx);
p->object = NULL;
if (p->wire_count != 0)
- goto unlist;
- VM_CNT_INC(v_pfree);
- p->flags &= ~PG_ZERO;
- if (p->queue != PQ_NONE) {
- KASSERT(p->queue < PQ_COUNT, ("vm_object_terminate: "
- "page %p is not queued", p));
- pq1 = vm_page_pagequeue(p);
- if (pq != pq1) {
- if (pq != NULL) {
- vm_pagequeue_cnt_add(pq, dequeued);
- vm_pagequeue_unlock(pq);
- }
- pq = pq1;
- vm_pagequeue_lock(pq);
- dequeued = 0;
- }
- p->queue = PQ_NONE;
- TAILQ_REMOVE(&pq->pq_pl, p, plinks.q);
- dequeued--;
- }
- if (vm_page_free_prep(p, true))
continue;
-unlist:
- TAILQ_REMOVE(&object->memq, p, listq);
- }
- if (pq != NULL) {
- vm_pagequeue_cnt_add(pq, dequeued);
- vm_pagequeue_unlock(pq);
+ VM_CNT_INC(v_pfree);
+ vm_page_free(p);
}
if (mtx != NULL)
mtx_unlock(mtx);
- vm_page_free_phys_pglist(&object->memq);
-
/*
* If the object contained any pages, then reset it to an empty state.
* None of the object's fields, including "resident_page_count", were
@@ -1973,7 +1931,6 @@
{
vm_page_t p, next;
struct mtx *mtx;
- struct pglist pgl;
VM_OBJECT_ASSERT_WLOCKED(object);
KASSERT((object->flags & OBJ_UNMANAGED) == 0 ||
@@ -1982,7 +1939,6 @@
if (object->resident_page_count == 0)
return;
vm_object_pip_add(object, 1);
- TAILQ_INIT(&pgl);
again:
p = vm_page_find_least(object, start);
mtx = NULL;
@@ -2036,13 +1992,10 @@
}
if ((options & OBJPR_NOTMAPPED) == 0 && object->ref_count != 0)
pmap_remove_all(p);
- p->flags &= ~PG_ZERO;
- if (vm_page_free_prep(p, false))
- TAILQ_INSERT_TAIL(&pgl, p, listq);
+ vm_page_free(p);
}
if (mtx != NULL)
mtx_unlock(mtx);
- vm_page_free_phys_pglist(&pgl);
vm_object_pip_wakeup(object);
}
Index: sys/vm/vm_page.h
===================================================================
--- sys/vm/vm_page.h
+++ sys/vm/vm_page.h
@@ -93,8 +93,11 @@
*
* In general, operations on this structure's mutable fields are
* synchronized using either one of or a combination of the lock on the
- * object that the page belongs to (O), the pool lock for the page (P),
- * or the lock for either the free or paging queue (Q). If a field is
+ * object that the page belongs to (O), the page lock (P),
+ * the per-domain lock for the free queues (F), or the page's queue
+ * lock (Q). The physical address of a page is used to select its page
+ * lock from a pool. The queue lock for a page depends on the value of
+ * its queue field and described in detail below. If a field is
* annotated below with two of these locks, then holding either lock is
* sufficient for read access, but both locks are required for write
* access. An annotation of (C) indicates that the field is immutable.
@@ -143,6 +146,29 @@
* causing the thread to block. vm_page_sleep_if_busy() can be used to
* sleep until the page's busy state changes, after which the caller
* must re-lookup the page and re-evaluate its state.
+ *
+ * The queue field is the index of the page queue containing the
+ * page, or PQ_NONE if the page is not enqueued. The queue lock of a
+ * page is the page queue lock corresponding to the page queue index,
+ * or the page lock (P) for the page if it is not enqueued. To modify
+ * the queue field, the queue lock for the old value of the field must
+ * be held. It is invalid for a page's queue field to transition
+ * between two distinct page queue indices. That is, when updating
+ * the queue field, either the new value or the old value must be
+ * PQ_NONE.
+ *
+ * To avoid contention on page queue locks, page queue operations
+ * (enqueue, dequeue, requeue) are batched using per-CPU queues.
+ * A deferred operation is requested by inserting an entry into a
+ * batch queue; the entry is simply a pointer to the page, and the
+ * request type is encoded in the page's aflags field using the values
+ * in PGA_QUEUE_STATE_MASK. The type-stability of struct vm_pages is
+ * crucial to this scheme since the processing of entries in a given
+ * batch queue may be deferred indefinitely. In particular, a page
+ * may be freed before its pending batch queue entries have been
+ * processed. The page lock (P) must be held to schedule a batched
+ * queue operation, and the page queue lock must be held in order to
+ * process batch queue entries for the page queue.
*/
#if PAGE_SIZE == 4096
@@ -174,7 +200,7 @@
TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */
vm_object_t object; /* which object am I in (O,P) */
vm_pindex_t pindex; /* offset into object (O,P) */
- vm_paddr_t phys_addr; /* physical address of page */
+ vm_paddr_t phys_addr; /* physical address of page (C) */
struct md_page md; /* machine dependent stuff */
u_int wire_count; /* wired down maps refs (P) */
volatile u_int busy_lock; /* busy owners lock */
@@ -182,11 +208,11 @@
uint16_t flags; /* page PG_* flags (P) */
uint8_t aflags; /* access is atomic */
uint8_t oflags; /* page VPO_* flags (O) */
- uint8_t queue; /* page queue index (P,Q) */
+ uint8_t queue; /* page queue index (Q) */
int8_t psind; /* pagesizes[] index (O) */
int8_t segind; /* vm_phys segment index (C) */
- uint8_t order; /* index of the buddy queue */
- uint8_t pool; /* vm_phys freepool index (Q) */
+ uint8_t order; /* index of the buddy queue (F) */
+ uint8_t pool; /* vm_phys freepool index (F) */
u_char act_count; /* page usage count (P) */
/* NOTE that these must support one bit per DEV_BSIZE in a page */
/* so, on normal X86 kernels, they must be at least 8 bits wide */
@@ -314,10 +340,38 @@
*
* PGA_EXECUTABLE may be set by pmap routines, and indicates that a page has
* at least one executable mapping. It is not consumed by the MI VM layer.
+ *
+ * PGA_ENQUEUED is set and cleared when a page is inserted into or removed
+ * from a page queue, respectively. It determines whether the plinks.q field
+ * of the page is valid. To set or clear this flag, the queue lock for the
+ * page must be held: the page queue lock corresponding to the page's "queue"
+ * field if its value is not PQ_NONE, and the page lock otherwise.
+ *
+ * PGA_DEQUEUE is set when the page is scheduled to be dequeued from a page
+ * queue, and cleared when the dequeue request is processed. A page may
+ * have PGA_DEQUEUE set and PGA_ENQUEUED cleared, for instance if a dequeue
+ * is requested after the page is scheduled to be enqueued but before it is
+ * actually inserted into the page queue. The page lock must be held to set
+ * this flag, and the queue lock for the page must be held to clear it.
+ *
+ * PGA_REQUEUE is set when the page is scheduled to be enqueued or requeued
+ * in its page queue. The page lock must be held to set this flag, and the
+ * queue lock for the page must be held to clear it.
+ *
+ * PGA_REQUEUE_HEAD is a special flag for enqueuing pages near the head of
+ * the inactive queue, thus bypassing LRU. The page lock must be held to
+ * set this flag, and the queue lock for the page must be held to clear it.
*/
#define PGA_WRITEABLE 0x01 /* page may be mapped writeable */
#define PGA_REFERENCED 0x02 /* page has been referenced */
#define PGA_EXECUTABLE 0x04 /* page may be mapped executable */
+#define PGA_ENQUEUED 0x08 /* page is enqueued in a page queue */
+#define PGA_DEQUEUE 0x10 /* page is due to be dequeued */
+#define PGA_REQUEUE 0x20 /* page is due to be requeued */
+#define PGA_REQUEUE_HEAD 0x40 /* page requeue should bypass LRU */
+
+#define PGA_QUEUE_STATE_MASK (PGA_ENQUEUED | PGA_DEQUEUE | PGA_REQUEUE | \
+ PGA_REQUEUE_HEAD)
/*
* Page flags. If changed at any other time than page allocation or
@@ -484,13 +538,13 @@
void vm_page_deactivate(vm_page_t);
void vm_page_deactivate_noreuse(vm_page_t);
void vm_page_dequeue(vm_page_t m);
+void vm_page_dequeue_deferred(vm_page_t m);
void vm_page_dequeue_locked(vm_page_t m);
+void vm_page_drain_pqbatch(void);
vm_page_t vm_page_find_least(vm_object_t, vm_pindex_t);
-void vm_page_free_phys_pglist(struct pglist *tq);
-bool vm_page_free_prep(vm_page_t m, bool pagequeue_locked);
+bool vm_page_free_prep(vm_page_t m);
vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr);
void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr);
-void vm_page_init_marker(vm_page_t m, int queue);
int vm_page_insert (vm_page_t, vm_object_t, vm_pindex_t);
void vm_page_launder(vm_page_t m);
vm_page_t vm_page_lookup (vm_object_t, vm_pindex_t);
@@ -752,6 +806,24 @@
return (m->queue == PQ_LAUNDRY || m->queue == PQ_UNSWAPPABLE);
}
+/*
+ * vm_page_enqueued:
+ *
+ * Return true if the page is logically enqueued and no deferred
+ * dequeue is pending.
+ */
+static inline bool
+vm_page_enqueued(vm_page_t m)
+{
+
+ vm_page_assert_locked(m);
+
+ if ((m->aflags & PGA_DEQUEUE) != 0)
+ return (false);
+ atomic_thread_fence_acq();
+ return (m->queue != PQ_NONE);
+}
+
/*
* vm_page_held:
*
Index: sys/vm/vm_page.c
===================================================================
--- sys/vm/vm_page.c
+++ sys/vm/vm_page.c
@@ -102,6 +102,7 @@
#include <sys/proc.h>
#include <sys/rwlock.h>
#include <sys/sbuf.h>
+#include <sys/sched.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#include <sys/vmmeter.h>
@@ -131,13 +132,10 @@
extern void uma_startup(void *, int);
extern int vmem_startup_count(void);
-/*
- * Associated with page of user-allocatable memory is a
- * page structure.
- */
-
struct vm_domain vm_dom[MAXMEMDOM];
+static DPCPU_DEFINE(struct vm_batchqueue, pqbatch[MAXMEMDOM][PQ_COUNT]);
+
struct mtx_padalign __exclusive_cache_line pa_lock[PA_LOCK_COUNT];
struct mtx_padalign __exclusive_cache_line vm_domainset_lock;
@@ -176,7 +174,8 @@
static void vm_page_alloc_check(vm_page_t m);
static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits);
-static void vm_page_enqueue(uint8_t queue, vm_page_t m);
+static void vm_page_dequeue_complete(vm_page_t m);
+static void vm_page_enqueue(vm_page_t m, uint8_t queue);
static void vm_page_init(void *dummy);
static int vm_page_insert_after(vm_page_t m, vm_object_t object,
vm_pindex_t pindex, vm_page_t mpred);
@@ -443,12 +442,13 @@
* Nonetheless, it write busies and initializes the hold count to one as
* safety precautions.
*/
-void
-vm_page_init_marker(vm_page_t marker, int queue)
+static void
+vm_page_init_marker(vm_page_t marker, int queue, uint8_t aflags)
{
bzero(marker, sizeof(*marker));
marker->flags = PG_MARKER;
+ marker->aflags = aflags;
marker->busy_lock = VPB_SINGLE_EXCLUSIVER;
marker->queue = queue;
marker->hold_count = 1;
@@ -481,14 +481,32 @@
TAILQ_INIT(&pq->pq_pl);
mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue",
MTX_DEF | MTX_DUPOK);
- vm_page_init_marker(&vmd->vmd_markers[i], i);
+ vm_page_init_marker(&vmd->vmd_markers[i], i, 0);
}
mtx_init(&vmd->vmd_free_mtx, "vm page free queue", NULL, MTX_DEF);
mtx_init(&vmd->vmd_pageout_mtx, "vm pageout lock", NULL, MTX_DEF);
- vm_page_init_marker(&vmd->vmd_inacthead, PQ_INACTIVE);
+ snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain);
+
+ /*
+ * inacthead is used to provide FIFO ordering for LRU-bypassing
+ * insertions.
+ */
+ vm_page_init_marker(&vmd->vmd_inacthead, PQ_INACTIVE, PGA_ENQUEUED);
TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_INACTIVE].pq_pl,
&vmd->vmd_inacthead, plinks.q);
- snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain);
+
+ /*
+ * The clock pages are used to implement active queue scanning without
+ * requeues. Scans start at clock[0], which is advanced after the scan
+ * ends. When the two clock hands meet, they are reset and scanning
+ * resumes from the head of the queue.
+ */
+ vm_page_init_marker(&vmd->vmd_clock[0], PQ_ACTIVE, PGA_ENQUEUED);
+ vm_page_init_marker(&vmd->vmd_clock[1], PQ_ACTIVE, PGA_ENQUEUED);
+ TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl,
+ &vmd->vmd_clock[0], plinks.q);
+ TAILQ_INSERT_TAIL(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl,
+ &vmd->vmd_clock[1], plinks.q);
}
/*
@@ -1847,6 +1865,7 @@
KASSERT(m != NULL, ("missing page"));
found:
+ vm_page_dequeue(m);
vm_page_alloc_check(m);
/*
@@ -2043,8 +2062,10 @@
#if VM_NRESERVLEVEL > 0
found:
#endif
- for (m = m_ret; m < &m_ret[npages]; m++)
+ for (m = m_ret; m < &m_ret[npages]; m++) {
+ vm_page_dequeue(m);
vm_page_alloc_check(m);
+ }
/*
* Initialize the pages. Only the PG_ZERO flag is inherited.
@@ -2188,6 +2209,7 @@
goto again;
return (NULL);
}
+ vm_page_dequeue(m);
vm_page_alloc_check(m);
/*
@@ -2381,7 +2403,7 @@
vm_reserv_size(level)) - pa);
#endif
} else if (object->memattr == VM_MEMATTR_DEFAULT &&
- m->queue != PQ_NONE && !vm_page_busied(m)) {
+ vm_page_enqueued(m) && !vm_page_busied(m)) {
/*
* The page is allocated but eligible for
* relocation. Extend the current run by one
@@ -2532,7 +2554,7 @@
error = EINVAL;
else if (object->memattr != VM_MEMATTR_DEFAULT)
error = EINVAL;
- else if (m->queue != PQ_NONE && !vm_page_busied(m)) {
+ else if (vm_page_enqueued(m) && !vm_page_busied(m)) {
KASSERT(pmap_page_get_memattr(m) ==
VM_MEMATTR_DEFAULT,
("page %p has an unexpected memattr", m));
@@ -2592,7 +2614,8 @@
*/
if (object->ref_count != 0)
pmap_remove_all(m);
- m_new->aflags = m->aflags;
+ m_new->aflags = m->aflags &
+ ~PGA_QUEUE_STATE_MASK;
KASSERT(m_new->oflags == VPO_UNMANAGED,
("page %p is managed", m_new));
m_new->oflags = m->oflags & VPO_NOSYNC;
@@ -2604,7 +2627,7 @@
vm_page_remque(m);
vm_page_replace_checked(m_new, object,
m->pindex, m);
- if (vm_page_free_prep(m, false))
+ if (vm_page_free_prep(m))
SLIST_INSERT_HEAD(&free, m,
plinks.s.ss);
@@ -2618,7 +2641,7 @@
m->flags &= ~PG_ZERO;
vm_page_remque(m);
vm_page_remove(m);
- if (vm_page_free_prep(m, false))
+ if (vm_page_free_prep(m))
SLIST_INSERT_HEAD(&free, m,
plinks.s.ss);
KASSERT(m->dirty == 0,
@@ -3061,113 +3084,297 @@
return (&vm_pagequeue_domain(m)->vmd_pagequeues[m->queue]);
}
+static struct mtx *
+vm_page_pagequeue_lockptr(vm_page_t m)
+{
+
+ if (m->queue == PQ_NONE)
+ return (NULL);
+ return (&vm_page_pagequeue(m)->pq_mutex);
+}
+
+static inline void
+vm_pqbatch_process_page(struct vm_pagequeue *pq, vm_page_t m)
+{
+ struct vm_domain *vmd;
+ uint8_t aflags;
+
+ vm_pagequeue_assert_locked(pq);
+ KASSERT(pq == vm_page_pagequeue(m),
+ ("page %p doesn't belong to %p", m, pq));
+
+ aflags = m->aflags;
+ if ((aflags & PGA_DEQUEUE) != 0) {
+ if (__predict_true((aflags & PGA_ENQUEUED) != 0)) {
+ TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
+ vm_pagequeue_cnt_dec(pq);
+ }
+ vm_page_dequeue_complete(m);
+ } else if ((aflags & (PGA_REQUEUE | PGA_REQUEUE_HEAD)) != 0) {
+ if ((aflags & PGA_ENQUEUED) != 0)
+ TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
+ else {
+ vm_pagequeue_cnt_inc(pq);
+ vm_page_aflag_set(m, PGA_ENQUEUED);
+ }
+ if ((aflags & PGA_REQUEUE_HEAD) != 0) {
+ KASSERT(m->queue == PQ_INACTIVE,
+ ("head enqueue not supported for page %p", m));
+ vmd = vm_pagequeue_domain(m);
+ TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q);
+ } else
+ TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
+
+ /*
+ * PGA_REQUEUE and PGA_REQUEUE_HEAD must be cleared after
+ * setting PGA_ENQUEUED in order to synchronize with the
+ * page daemon.
+ */
+ vm_page_aflag_clear(m, PGA_REQUEUE | PGA_REQUEUE_HEAD);
+ }
+}
+
+static void
+vm_pqbatch_process(struct vm_pagequeue *pq, struct vm_batchqueue *bq,
+ uint8_t queue)
+{
+ vm_page_t m;
+ int i;
+
+ for (i = 0; i < bq->bq_cnt; i++) {
+ m = bq->bq_pa[i];
+ if (__predict_false(m->queue != queue))
+ continue;
+ vm_pqbatch_process_page(pq, m);
+ }
+ vm_batchqueue_init(bq);
+}
+
+static void
+vm_pqbatch_submit_page(vm_page_t m, uint8_t queue)
+{
+ struct vm_batchqueue *bq;
+ struct vm_pagequeue *pq;
+ int domain;
+
+ vm_page_assert_locked(m);
+ KASSERT(queue < PQ_COUNT, ("invalid queue %d", queue));
+
+ domain = vm_phys_domain(m);
+ pq = &vm_pagequeue_domain(m)->vmd_pagequeues[queue];
+
+ critical_enter();
+ bq = DPCPU_PTR(pqbatch[domain][queue]);
+ if (vm_batchqueue_insert(bq, m)) {
+ critical_exit();
+ return;
+ }
+ if (!vm_pagequeue_trylock(pq)) {
+ critical_exit();
+ vm_pagequeue_lock(pq);
+ critical_enter();
+ bq = DPCPU_PTR(pqbatch[domain][queue]);
+ }
+ vm_pqbatch_process(pq, bq, queue);
+
+ /*
+ * The page may have been logically dequeued before we acquired the
+ * page queue lock. In this case, the page lock prevents the page
+ * from being logically enqueued elsewhere.
+ */
+ if (__predict_true(m->queue == queue))
+ vm_pqbatch_process_page(pq, m);
+ else {
+ KASSERT(m->queue == PQ_NONE,
+ ("invalid queue transition for page %p", m));
+ KASSERT((m->aflags & PGA_ENQUEUED) == 0,
+ ("page %p is enqueued with invalid queue index", m));
+ vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK);
+ }
+ vm_pagequeue_unlock(pq);
+ critical_exit();
+}
+
/*
- * vm_page_dequeue:
+ * vm_page_drain_pqbatch: [ internal use only ]
+ *
+ * Force all per-CPU page queue batch queues to be drained. This is
+ * intended for use in severe memory shortages, to ensure that pages
+ * do not remain stuck in the batch queues.
+ */
+void
+vm_page_drain_pqbatch(void)
+{
+ struct thread *td;
+ struct vm_domain *vmd;
+ struct vm_pagequeue *pq;
+ int cpu, domain, queue;
+
+ td = curthread;
+ CPU_FOREACH(cpu) {
+ thread_lock(td);
+ sched_bind(td, cpu);
+ thread_unlock(td);
+
+ for (domain = 0; domain < vm_ndomains; domain++) {
+ vmd = VM_DOMAIN(domain);
+ for (queue = 0; queue < PQ_COUNT; queue++) {
+ pq = &vmd->vmd_pagequeues[queue];
+ vm_pagequeue_lock(pq);
+ critical_enter();
+ vm_pqbatch_process(pq,
+ DPCPU_PTR(pqbatch[domain][queue]), queue);
+ critical_exit();
+ vm_pagequeue_unlock(pq);
+ }
+ }
+ }
+ thread_lock(td);
+ sched_unbind(td);
+ thread_unlock(td);
+}
+
+/*
+ * Complete the logical removal of a page from a page queue. We must be
+ * careful to synchronize with the page daemon, which may be concurrently
+ * examining the page with only the page lock held. The page must not be
+ * in a state where it appears to be logically enqueued.
+ */
+static void
+vm_page_dequeue_complete(vm_page_t m)
+{
+
+ m->queue = PQ_NONE;
+ atomic_thread_fence_rel();
+ vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK);
+}
+
+/*
+ * vm_page_dequeue_deferred: [ internal use only ]
*
- * Remove the given page from its current page queue.
+ * Request removal of the given page from its current page
+ * queue. Physical removal from the queue may be deferred
+ * indefinitely.
*
* The page must be locked.
*/
void
-vm_page_dequeue(vm_page_t m)
+vm_page_dequeue_deferred(vm_page_t m)
{
- struct vm_pagequeue *pq;
+ int queue;
vm_page_assert_locked(m);
- KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued",
- m));
- pq = vm_page_pagequeue(m);
- vm_pagequeue_lock(pq);
- m->queue = PQ_NONE;
- TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
- vm_pagequeue_cnt_dec(pq);
- vm_pagequeue_unlock(pq);
+
+ queue = m->queue;
+ if (queue == PQ_NONE) {
+ KASSERT((m->aflags & PGA_QUEUE_STATE_MASK) == 0,
+ ("page %p has queue state", m));
+ return;
+ }
+ if ((m->aflags & PGA_DEQUEUE) == 0)
+ vm_page_aflag_set(m, PGA_DEQUEUE);
+ vm_pqbatch_submit_page(m, queue);
}
/*
* vm_page_dequeue_locked:
*
- * Remove the given page from its current page queue.
+ * Remove the page from its page queue, which must be locked.
+ * If the page lock is not held, there is no guarantee that the
+ * page will not be enqueued by another thread before this function
+ * returns. In this case, it is up to the caller to ensure that
+ * no other threads hold a reference to the page.
*
- * The page and page queue must be locked.
+ * The page queue lock must be held. If the page is not already
+ * logically dequeued, the page lock must be held as well.
*/
void
vm_page_dequeue_locked(vm_page_t m)
{
struct vm_pagequeue *pq;
- vm_page_lock_assert(m, MA_OWNED);
pq = vm_page_pagequeue(m);
+
+ KASSERT(m->queue != PQ_NONE,
+ ("%s: page %p queue field is PQ_NONE", __func__, m));
vm_pagequeue_assert_locked(pq);
- m->queue = PQ_NONE;
- TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
- vm_pagequeue_cnt_dec(pq);
+ KASSERT((m->aflags & PGA_DEQUEUE) != 0 ||
+ mtx_owned(vm_page_lockptr(m)),
+ ("%s: queued unlocked page %p", __func__, m));
+
+ if ((m->aflags & PGA_ENQUEUED) != 0) {
+ TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
+ vm_pagequeue_cnt_dec(pq);
+ }
+ vm_page_dequeue_complete(m);
}
/*
- * vm_page_enqueue:
- *
- * Add the given page to the specified page queue.
+ * vm_page_dequeue:
*
- * The page must be locked.
+ * Remove the page from whichever page queue it's in, if any.
+ * If the page lock is not held, there is no guarantee that the
+ * page will not be enqueued by another thread before this function
+ * returns. In this case, it is up to the caller to ensure that
+ * no other threads hold a reference to the page.
*/
-static void
-vm_page_enqueue(uint8_t queue, vm_page_t m)
+void
+vm_page_dequeue(vm_page_t m)
{
- struct vm_pagequeue *pq;
+ struct mtx *lock, *lock1;
- vm_page_lock_assert(m, MA_OWNED);
- KASSERT(queue < PQ_COUNT,
- ("vm_page_enqueue: invalid queue %u request for page %p",
- queue, m));
- pq = &vm_pagequeue_domain(m)->vmd_pagequeues[queue];
- vm_pagequeue_lock(pq);
- m->queue = queue;
- TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
- vm_pagequeue_cnt_inc(pq);
- vm_pagequeue_unlock(pq);
+ lock = vm_page_pagequeue_lockptr(m);
+ for (;;) {
+ if (lock == NULL)
+ return;
+ mtx_lock(lock);
+ if ((lock1 = vm_page_pagequeue_lockptr(m)) == lock)
+ break;
+ mtx_unlock(lock);
+ lock = lock1;
+ }
+ KASSERT(lock == vm_page_pagequeue_lockptr(m),
+ ("%s: page %p migrated directly between queues", __func__, m));
+ vm_page_dequeue_locked(m);
+ mtx_unlock(lock);
}
/*
- * vm_page_requeue:
- *
- * Move the given page to the tail of its current page queue.
- *
- * The page must be locked.
+ * Schedule the given page for insertion into the specified page queue.
+ * Physical insertion of the page may be deferred indefinitely.
*/
-void
-vm_page_requeue(vm_page_t m)
+static void
+vm_page_enqueue(vm_page_t m, uint8_t queue)
{
- struct vm_pagequeue *pq;
- vm_page_lock_assert(m, MA_OWNED);
- KASSERT(m->queue != PQ_NONE,
- ("vm_page_requeue: page %p is not queued", m));
- pq = vm_page_pagequeue(m);
- vm_pagequeue_lock(pq);
- TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
- TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
- vm_pagequeue_unlock(pq);
+ vm_page_assert_locked(m);
+ KASSERT(m->queue == PQ_NONE && (m->aflags & PGA_QUEUE_STATE_MASK) == 0,
+ ("%s: page %p is already enqueued", __func__, m));
+
+ m->queue = queue;
+ if ((m->aflags & PGA_REQUEUE) == 0)
+ vm_page_aflag_set(m, PGA_REQUEUE);
+ vm_pqbatch_submit_page(m, queue);
}
/*
- * vm_page_requeue_locked:
+ * vm_page_requeue: [ internal use only ]
*
- * Move the given page to the tail of its current page queue.
+ * Schedule a requeue of the given page.
*
- * The page queue must be locked.
+ * The page must be locked.
*/
void
-vm_page_requeue_locked(vm_page_t m)
+vm_page_requeue(vm_page_t m)
{
- struct vm_pagequeue *pq;
+ vm_page_assert_locked(m);
KASSERT(m->queue != PQ_NONE,
- ("vm_page_requeue_locked: page %p is not queued", m));
- pq = vm_page_pagequeue(m);
- vm_pagequeue_assert_locked(pq);
- TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
- TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
+ ("%s: page %p is not logically enqueued", __func__, m));
+
+ if ((m->aflags & PGA_REQUEUE) == 0)
+ vm_page_aflag_set(m, PGA_REQUEUE);
+ vm_pqbatch_submit_page(m, m->queue);
}
/*
@@ -3185,18 +3392,18 @@
int queue;
vm_page_lock_assert(m, MA_OWNED);
- if ((queue = m->queue) != PQ_ACTIVE) {
- if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
- if (m->act_count < ACT_INIT)
- m->act_count = ACT_INIT;
- if (queue != PQ_NONE)
- vm_page_dequeue(m);
- vm_page_enqueue(PQ_ACTIVE, m);
- }
- } else {
- if (m->act_count < ACT_INIT)
+
+ if ((queue = m->queue) == PQ_ACTIVE || m->wire_count > 0 ||
+ (m->oflags & VPO_UNMANAGED) != 0) {
+ if (queue == PQ_ACTIVE && m->act_count < ACT_INIT)
m->act_count = ACT_INIT;
+ return;
}
+
+ vm_page_remque(m);
+ if (m->act_count < ACT_INIT)
+ m->act_count = ACT_INIT;
+ vm_page_enqueue(m, PQ_ACTIVE);
}
/*
@@ -3207,11 +3414,10 @@
* the page to the free list only if this function returns true.
*
* The object must be locked. The page must be locked if it is
- * managed. For a queued managed page, the pagequeue_locked
- * argument specifies whether the page queue is already locked.
+ * managed.
*/
bool
-vm_page_free_prep(vm_page_t m, bool pagequeue_locked)
+vm_page_free_prep(vm_page_t m)
{
#if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP)
@@ -3227,14 +3433,14 @@
if ((m->oflags & VPO_UNMANAGED) == 0) {
vm_page_lock_assert(m, MA_OWNED);
KASSERT(!pmap_page_is_mapped(m),
- ("vm_page_free_toq: freeing mapped page %p", m));
+ ("vm_page_free_prep: freeing mapped page %p", m));
} else
KASSERT(m->queue == PQ_NONE,
- ("vm_page_free_toq: unmanaged page %p is queued", m));
+ ("vm_page_free_prep: unmanaged page %p is queued", m));
VM_CNT_INC(v_tfree);
if (vm_page_sbusied(m))
- panic("vm_page_free: freeing busy page %p", m);
+ panic("vm_page_free_prep: freeing busy page %p", m);
vm_page_remove(m);
@@ -3250,21 +3456,23 @@
return (false);
}
- if (m->queue != PQ_NONE) {
- if (pagequeue_locked)
- vm_page_dequeue_locked(m);
- else
- vm_page_dequeue(m);
- }
+ /*
+ * Pages need not be dequeued before they are returned to the physical
+ * memory allocator, but they must at least be marked for a deferred
+ * dequeue.
+ */
+ if ((m->oflags & VPO_UNMANAGED) == 0)
+ vm_page_dequeue_deferred(m);
+
m->valid = 0;
vm_page_undirty(m);
if (m->wire_count != 0)
- panic("vm_page_free: freeing wired page %p", m);
+ panic("vm_page_free_prep: freeing wired page %p", m);
if (m->hold_count != 0) {
m->flags &= ~PG_ZERO;
KASSERT((m->flags & PG_UNHOLDFREE) == 0,
- ("vm_page_free: freeing PG_UNHOLDFREE page %p", m));
+ ("vm_page_free_prep: freeing PG_UNHOLDFREE page %p", m));
m->flags |= PG_UNHOLDFREE;
return (false);
}
@@ -3283,36 +3491,6 @@
return (true);
}
-void
-vm_page_free_phys_pglist(struct pglist *tq)
-{
- struct vm_domain *vmd;
- vm_page_t m;
- int cnt;
-
- if (TAILQ_EMPTY(tq))
- return;
- vmd = NULL;
- cnt = 0;
- TAILQ_FOREACH(m, tq, listq) {
- if (vmd != vm_pagequeue_domain(m)) {
- if (vmd != NULL) {
- vm_domain_free_unlock(vmd);
- vm_domain_freecnt_inc(vmd, cnt);
- cnt = 0;
- }
- vmd = vm_pagequeue_domain(m);
- vm_domain_free_lock(vmd);
- }
- vm_phys_free_pages(m, 0);
- cnt++;
- }
- if (vmd != NULL) {
- vm_domain_free_unlock(vmd);
- vm_domain_freecnt_inc(vmd, cnt);
- }
-}
-
/*
* vm_page_free_toq:
*
@@ -3327,7 +3505,7 @@
{
struct vm_domain *vmd;
- if (!vm_page_free_prep(m, false))
+ if (!vm_page_free_prep(m))
return;
vmd = vm_pagequeue_domain(m);
@@ -3425,22 +3603,25 @@
KASSERT(queue < PQ_COUNT || queue == PQ_NONE,
("vm_page_unwire: invalid queue %u request for page %p",
queue, m));
+ if ((m->oflags & VPO_UNMANAGED) == 0)
+ vm_page_assert_locked(m);
unwired = vm_page_unwire_noq(m);
- if (unwired && (m->oflags & VPO_UNMANAGED) == 0 && m->object != NULL) {
- if (m->queue == queue) {
+ if (!unwired || (m->oflags & VPO_UNMANAGED) != 0 || m->object == NULL)
+ return (unwired);
+
+ if (m->queue == queue) {
+ if (queue == PQ_ACTIVE)
+ vm_page_reference(m);
+ else if (queue != PQ_NONE)
+ vm_page_requeue(m);
+ } else {
+ vm_page_dequeue(m);
+ if (queue != PQ_NONE) {
+ vm_page_enqueue(m, queue);
if (queue == PQ_ACTIVE)
- vm_page_reference(m);
- else if (queue != PQ_NONE)
- vm_page_requeue(m);
- } else {
- vm_page_remque(m);
- if (queue != PQ_NONE) {
- vm_page_enqueue(queue, m);
- if (queue == PQ_ACTIVE)
- /* Initialize act_count. */
- vm_page_activate(m);
- }
+ /* Initialize act_count. */
+ vm_page_activate(m);
}
}
return (unwired);
@@ -3476,65 +3657,32 @@
}
/*
- * Move the specified page to the inactive queue, or requeue the page if it is
- * already in the inactive queue.
- *
- * Normally, "noreuse" is FALSE, resulting in LRU ordering of the inactive
- * queue. However, setting "noreuse" to TRUE will accelerate the specified
- * page's reclamation, but it will not unmap the page from any address space.
- * This is implemented by inserting the page near the head of the inactive
- * queue, using a marker page to guide FIFO insertion ordering.
+ * Move the specified page to the tail of the inactive queue, or requeue
+ * the page if it is already in the inactive queue.
*
* The page must be locked.
*/
-static inline void
-_vm_page_deactivate(vm_page_t m, boolean_t noreuse)
+void
+vm_page_deactivate(vm_page_t m)
{
- struct vm_pagequeue *pq;
- int queue;
vm_page_assert_locked(m);
- if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
- pq = &vm_pagequeue_domain(m)->vmd_pagequeues[PQ_INACTIVE];
- /* Avoid multiple acquisitions of the inactive queue lock. */
- queue = m->queue;
- if (queue == PQ_INACTIVE) {
- vm_pagequeue_lock(pq);
- vm_page_dequeue_locked(m);
- } else {
- if (queue != PQ_NONE)
- vm_page_dequeue(m);
- vm_pagequeue_lock(pq);
- }
- m->queue = PQ_INACTIVE;
- if (noreuse)
- TAILQ_INSERT_BEFORE(
- &vm_pagequeue_domain(m)->vmd_inacthead, m,
- plinks.q);
- else
- TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
- vm_pagequeue_cnt_inc(pq);
- vm_pagequeue_unlock(pq);
- }
-}
-
-/*
- * Move the specified page to the inactive queue, or requeue the page if it is
- * already in the inactive queue.
- *
- * The page must be locked.
- */
-void
-vm_page_deactivate(vm_page_t m)
-{
+ if (m->wire_count > 0 || (m->oflags & VPO_UNMANAGED) != 0)
+ return;
- _vm_page_deactivate(m, FALSE);
+ if (!vm_page_inactive(m)) {
+ vm_page_remque(m);
+ vm_page_enqueue(m, PQ_INACTIVE);
+ } else
+ vm_page_requeue(m);
}
/*
- * Move the specified page to the inactive queue with the expectation
- * that it is unlikely to be reused.
+ * Move the specified page close to the head of the inactive queue,
+ * bypassing LRU. A marker page is used to maintain FIFO ordering.
+ * As with regular enqueues, we use a per-CPU batch queue to reduce
+ * contention on the page queue lock.
*
* The page must be locked.
*/
@@ -3542,7 +3690,17 @@
vm_page_deactivate_noreuse(vm_page_t m)
{
- _vm_page_deactivate(m, TRUE);
+ vm_page_assert_locked(m);
+
+ if (m->wire_count > 0 || (m->oflags & VPO_UNMANAGED) != 0)
+ return;
+
+ if (!vm_page_inactive(m))
+ vm_page_remque(m);
+ m->queue = PQ_INACTIVE;
+ if ((m->aflags & PGA_REQUEUE_HEAD) == 0)
+ vm_page_aflag_set(m, PGA_REQUEUE_HEAD);
+ vm_pqbatch_submit_page(m, PQ_INACTIVE);
}
/*
@@ -3555,13 +3713,14 @@
{
vm_page_assert_locked(m);
- if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) {
- if (m->queue == PQ_LAUNDRY)
- vm_page_requeue(m);
- else {
- vm_page_remque(m);
- vm_page_enqueue(PQ_LAUNDRY, m);
- }
+ if (m->wire_count > 0 || (m->oflags & VPO_UNMANAGED) != 0)
+ return;
+
+ if (m->queue == PQ_LAUNDRY)
+ vm_page_requeue(m);
+ else {
+ vm_page_remque(m);
+ vm_page_enqueue(m, PQ_LAUNDRY);
}
}
@@ -3577,9 +3736,9 @@
vm_page_assert_locked(m);
KASSERT(m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0,
("page %p already unswappable", m));
- if (m->queue != PQ_NONE)
- vm_page_dequeue(m);
- vm_page_enqueue(PQ_UNSWAPPABLE, m);
+
+ vm_page_remque(m);
+ vm_page_enqueue(m, PQ_UNSWAPPABLE);
}
/*
Index: sys/vm/vm_pageout.c
===================================================================
--- sys/vm/vm_pageout.c
+++ sys/vm/vm_pageout.c
@@ -201,103 +201,134 @@
CTLFLAG_RW, &vm_page_max_wired, 0, "System-wide limit to wired page count");
static u_int isqrt(u_int num);
-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);
-static boolean_t vm_pageout_page_lock(vm_page_t, vm_page_t *);
+
+struct scan_state {
+ struct vm_batchqueue bq;
+ struct vm_pagequeue *pq;
+ vm_page_t marker;
+ int maxscan;
+ int scanned;
+};
+
+static void
+vm_pageout_init_scan(struct scan_state *ss, struct vm_pagequeue *pq,
+ vm_page_t marker, vm_page_t after, int maxscan)
+{
+
+ vm_pagequeue_assert_locked(pq);
+ KASSERT((marker->aflags & PGA_ENQUEUED) == 0,
+ ("marker %p already enqueued", marker));
+
+ if (after == NULL)
+ TAILQ_INSERT_HEAD(&pq->pq_pl, marker, plinks.q);
+ else
+ TAILQ_INSERT_AFTER(&pq->pq_pl, after, marker, plinks.q);
+ vm_page_aflag_set(marker, PGA_ENQUEUED);
+
+ vm_batchqueue_init(&ss->bq);
+ ss->pq = pq;
+ ss->marker = marker;
+ ss->maxscan = maxscan;
+ ss->scanned = 0;
+ vm_pagequeue_unlock(pq);
+}
+
+static void
+vm_pageout_end_scan(struct scan_state *ss)
+{
+ struct vm_pagequeue *pq;
+
+ pq = ss->pq;
+ vm_pagequeue_assert_locked(pq);
+ KASSERT((ss->marker->aflags & PGA_ENQUEUED) != 0,
+ ("marker %p not enqueued", ss->marker));
+
+ TAILQ_REMOVE(&pq->pq_pl, ss->marker, plinks.q);
+ vm_page_aflag_clear(ss->marker, PGA_ENQUEUED);
+ VM_CNT_ADD(v_pdpages, ss->scanned);
+}
/*
- * vm_pageout_fallback_object_lock:
- *
- * Lock vm object currently associated with `m'. VM_OBJECT_TRYWLOCK is
- * known to have failed and page queue must be either PQ_ACTIVE or
- * PQ_INACTIVE. To avoid lock order violation, unlock the page queue
- * while locking the vm object. Use marker page to detect page queue
- * changes and maintain notion of next page on page queue. Return
- * TRUE if no changes were detected, FALSE otherwise. vm object is
- * locked on return.
- *
- * This function depends on both the lock portion of struct vm_object
- * and normal struct vm_page being type stable.
+ * Ensure that the page has not been dequeued after a pageout batch was
+ * collected. See vm_page_dequeue_complete().
*/
-static boolean_t
-vm_pageout_fallback_object_lock(vm_page_t m, vm_page_t *next)
+static inline bool
+vm_pageout_page_queued(vm_page_t m, int queue)
{
- struct vm_page marker;
- struct vm_pagequeue *pq;
- boolean_t unchanged;
- vm_object_t object;
- int queue;
- queue = m->queue;
- vm_page_init_marker(&marker, queue);
- pq = vm_page_pagequeue(m);
- object = m->object;
-
- TAILQ_INSERT_AFTER(&pq->pq_pl, m, &marker, plinks.q);
- vm_pagequeue_unlock(pq);
- vm_page_unlock(m);
- VM_OBJECT_WLOCK(object);
- vm_page_lock(m);
- vm_pagequeue_lock(pq);
+ vm_page_assert_locked(m);
- /*
- * The page's object might have changed, and/or the page might
- * have moved from its original position in the queue. If the
- * page's object has changed, then the caller should abandon
- * processing the page because the wrong object lock was
- * acquired. Use the marker's plinks.q, not the page's, to
- * determine if the page has been moved. The state of the
- * page's plinks.q can be indeterminate; whereas, the marker's
- * plinks.q must be valid.
- */
- *next = TAILQ_NEXT(&marker, plinks.q);
- unchanged = m->object == object &&
- m == TAILQ_PREV(&marker, pglist, plinks.q);
- KASSERT(!unchanged || m->queue == queue,
- ("page %p queue %d %d", m, queue, m->queue));
- TAILQ_REMOVE(&pq->pq_pl, &marker, plinks.q);
- return (unchanged);
+ if ((m->aflags & PGA_DEQUEUE) != 0)
+ return (false);
+ atomic_thread_fence_acq();
+ return (m->queue == queue);
}
/*
- * Lock the page while holding the page queue lock. Use marker page
- * to detect page queue changes and maintain notion of next page on
- * page queue. Return TRUE if no changes were detected, FALSE
- * otherwise. The page is locked on return. The page queue lock might
- * be dropped and reacquired.
+ * Add a small number of queued pages to a batch queue for later processing
+ * without the corresponding queue lock held. The caller must have enqueued a
+ * marker page at the desired start point for the scan. Pages will be
+ * physically dequeued if the caller so requests. Otherwise, the returned
+ * batch may contain marker pages, and it is up to the caller to handle them.
*
- * This function depends on normal struct vm_page being type stable.
+ * When processing the batch queue, vm_pageout_page_queued() must be used to
+ * determine whether the page was logically dequeued by another thread. Once
+ * this check is performed, the page lock guarantees that the page will not be
+ * disassociated from the queue.
*/
-static boolean_t
-vm_pageout_page_lock(vm_page_t m, vm_page_t *next)
+static __always_inline void
+vm_pageout_collect_batch(struct scan_state *ss, const bool dequeue)
{
- struct vm_page marker;
struct vm_pagequeue *pq;
- boolean_t unchanged;
- int queue;
+ vm_page_t m, marker;
- vm_page_lock_assert(m, MA_NOTOWNED);
- if (vm_page_trylock(m))
- return (TRUE);
+ marker = ss->marker;
+ pq = ss->pq;
- queue = m->queue;
- vm_page_init_marker(&marker, queue);
- pq = vm_page_pagequeue(m);
+ KASSERT((marker->aflags & PGA_ENQUEUED) != 0,
+ ("marker %p not enqueued", ss->marker));
- TAILQ_INSERT_AFTER(&pq->pq_pl, m, &marker, plinks.q);
- vm_pagequeue_unlock(pq);
- vm_page_lock(m);
vm_pagequeue_lock(pq);
+ for (m = TAILQ_NEXT(marker, plinks.q); m != NULL &&
+ ss->scanned < ss->maxscan && ss->bq.bq_cnt < VM_BATCHQUEUE_SIZE;
+ m = TAILQ_NEXT(m, plinks.q), ss->scanned++) {
+ if ((m->flags & PG_MARKER) == 0) {
+ KASSERT((m->aflags & PGA_ENQUEUED) != 0,
+ ("page %p not enqueued", m));
+ KASSERT((m->flags & PG_FICTITIOUS) == 0,
+ ("Fictitious page %p cannot be in page queue", m));
+ KASSERT((m->oflags & VPO_UNMANAGED) == 0,
+ ("Unmanaged page %p cannot be in page queue", m));
+ } else if (dequeue)
+ continue;
+
+ (void)vm_batchqueue_insert(&ss->bq, m);
+ if (dequeue) {
+ TAILQ_REMOVE(&pq->pq_pl, m, plinks.q);
+ vm_page_aflag_clear(m, PGA_ENQUEUED);
+ }
+ }
+ TAILQ_REMOVE(&pq->pq_pl, marker, plinks.q);
+ if (__predict_true(m != NULL))
+ TAILQ_INSERT_BEFORE(m, marker, plinks.q);
+ else
+ TAILQ_INSERT_TAIL(&pq->pq_pl, marker, plinks.q);
+ if (dequeue)
+ vm_pagequeue_cnt_add(pq, -ss->bq.bq_cnt);
+ vm_pagequeue_unlock(pq);
+}
+
+/* Return the next page to be scanned, or NULL if the scan is complete. */
+static __always_inline vm_page_t
+vm_pageout_next(struct scan_state *ss, const bool dequeue)
+{
- /* Page queue might have changed. */
- *next = TAILQ_NEXT(&marker, plinks.q);
- unchanged = m == TAILQ_PREV(&marker, pglist, plinks.q);
- KASSERT(!unchanged || m->queue == queue,
- ("page %p queue %d %d", m, queue, m->queue));
- TAILQ_REMOVE(&pq->pq_pl, &marker, plinks.q);
- return (unchanged);
+ if (ss->bq.bq_cnt == 0)
+ vm_pageout_collect_batch(ss, dequeue);
+ return (vm_batchqueue_pop(&ss->bq));
}
/*
@@ -353,12 +384,12 @@
break;
}
vm_page_test_dirty(p);
- if (p->dirty == 0) {
+ if (p->dirty == 0 || !vm_page_in_laundry(p)) {
ib = 0;
break;
}
vm_page_lock(p);
- if (!vm_page_in_laundry(p) || vm_page_held(p)) {
+ if (vm_page_held(p)) {
vm_page_unlock(p);
ib = 0;
break;
@@ -381,10 +412,10 @@
if ((p = vm_page_next(ps)) == NULL || vm_page_busied(p))
break;
vm_page_test_dirty(p);
- if (p->dirty == 0)
+ if (p->dirty == 0 || !vm_page_in_laundry(p))
break;
vm_page_lock(p);
- if (!vm_page_in_laundry(p) || vm_page_held(p)) {
+ if (vm_page_held(p)) {
vm_page_unlock(p);
break;
}
@@ -675,13 +706,18 @@
static int
vm_pageout_launder(struct vm_domain *vmd, int launder, bool in_shortfall)
{
+ struct scan_state ss;
struct vm_pagequeue *pq;
+ struct mtx *mtx;
vm_object_t object;
- vm_page_t m, marker, next;
- int act_delta, error, maxscan, numpagedout, queue, starting_target;
+ vm_page_t m, marker;
+ int act_delta, error, numpagedout, queue, starting_target;
int vnodes_skipped;
- bool pageout_ok, queue_locked;
+ bool obj_locked, pageout_ok;
+ mtx = NULL;
+ obj_locked = false;
+ object = NULL;
starting_target = launder;
vnodes_skipped = 0;
@@ -691,10 +727,6 @@
* we've reached the end of the queue. A single iteration of this loop
* may cause more than one page to be laundered because of clustering.
*
- * maxscan ensures that we don't re-examine requeued pages. Any
- * additional pages written as part of a cluster are subtracted from
- * maxscan since they must be taken from the laundry queue.
- *
* As an optimization, we avoid laundering from PQ_UNSWAPPABLE when no
* swap devices are configured.
*/
@@ -704,53 +736,68 @@
queue = PQ_LAUNDRY;
scan:
- pq = &vmd->vmd_pagequeues[queue];
marker = &vmd->vmd_markers[queue];
-
+ pq = &vmd->vmd_pagequeues[queue];
vm_pagequeue_lock(pq);
- maxscan = pq->pq_cnt;
- queue_locked = true;
- for (m = TAILQ_FIRST(&pq->pq_pl);
- m != NULL && maxscan-- > 0 && launder > 0;
- m = next) {
- vm_pagequeue_assert_locked(pq);
- KASSERT(queue_locked, ("unlocked laundry queue"));
- KASSERT(vm_page_in_laundry(m),
- ("page %p has an inconsistent queue", m));
- next = TAILQ_NEXT(m, plinks.q);
- if ((m->flags & PG_MARKER) != 0)
+ vm_pageout_init_scan(&ss, pq, marker, NULL, pq->pq_cnt);
+ while (launder > 0 && (m = vm_pageout_next(&ss, false)) != NULL) {
+ if (__predict_false((m->flags & PG_MARKER) != 0))
continue;
- KASSERT((m->flags & PG_FICTITIOUS) == 0,
- ("PG_FICTITIOUS page %p cannot be in laundry queue", m));
- KASSERT((m->oflags & VPO_UNMANAGED) == 0,
- ("VPO_UNMANAGED page %p cannot be in laundry queue", m));
- if (!vm_pageout_page_lock(m, &next) || m->hold_count != 0) {
- vm_page_unlock(m);
+
+ vm_page_change_lock(m, &mtx);
+
+recheck:
+ /*
+ * The page may have been disassociated from the queue
+ * while locks were dropped.
+ */
+ if (!vm_pageout_page_queued(m, queue))
+ continue;
+
+ /*
+ * A requeue was requested, so this page gets a second
+ * chance.
+ */
+ if ((m->aflags & PGA_REQUEUE) != 0) {
+ vm_page_requeue(m);
continue;
}
+
+ /*
+ * Held pages are essentially stuck in the queue.
+ *
+ * Wired pages may not be freed. Complete their removal
+ * from the queue now to avoid needless revisits during
+ * future scans.
+ */
+ if (m->hold_count != 0)
+ continue;
if (m->wire_count != 0) {
- vm_page_dequeue_locked(m);
- vm_page_unlock(m);
+ vm_page_dequeue_deferred(m);
continue;
}
- object = m->object;
- if ((!VM_OBJECT_TRYWLOCK(object) &&
- (!vm_pageout_fallback_object_lock(m, &next) ||
- vm_page_held(m))) || vm_page_busied(m)) {
- VM_OBJECT_WUNLOCK(object);
- if (m->wire_count != 0 && vm_page_pagequeue(m) == pq)
- vm_page_dequeue_locked(m);
- vm_page_unlock(m);
- continue;
+
+ if (object != m->object) {
+ if (obj_locked) {
+ VM_OBJECT_WUNLOCK(object);
+ obj_locked = false;
+ }
+ object = m->object;
+ }
+ if (!obj_locked) {
+ if (!VM_OBJECT_TRYWLOCK(object)) {
+ mtx_unlock(mtx);
+ /* Depends on type-stability. */
+ VM_OBJECT_WLOCK(object);
+ obj_locked = true;
+ mtx_lock(mtx);
+ goto recheck;
+ } else
+ obj_locked = true;
}
- /*
- * Unlock the laundry queue, invalidating the 'next' pointer.
- * Use a marker to remember our place in the laundry queue.
- */
- TAILQ_INSERT_AFTER(&pq->pq_pl, m, marker, plinks.q);
- vm_pagequeue_unlock(pq);
- queue_locked = false;
+ if (vm_page_busied(m))
+ continue;
/*
* Invalid pages can be easily freed. They cannot be
@@ -799,9 +846,11 @@
*/
if (!in_shortfall)
launder--;
- goto drop_page;
- } else if ((object->flags & OBJ_DEAD) == 0)
- goto requeue_page;
+ continue;
+ } else if ((object->flags & OBJ_DEAD) == 0) {
+ vm_page_requeue(m);
+ continue;
+ }
}
/*
@@ -836,11 +885,8 @@
else
pageout_ok = true;
if (!pageout_ok) {
-requeue_page:
- vm_pagequeue_lock(pq);
- queue_locked = true;
- vm_page_requeue_locked(m);
- goto drop_page;
+ vm_page_requeue(m);
+ continue;
}
/*
@@ -859,24 +905,25 @@
error = vm_pageout_clean(m, &numpagedout);
if (error == 0) {
launder -= numpagedout;
- maxscan -= numpagedout - 1;
+ ss.scanned += numpagedout;
} else if (error == EDEADLK) {
pageout_lock_miss++;
vnodes_skipped++;
}
- goto relock_queue;
+ mtx = NULL;
+ obj_locked = false;
}
-drop_page:
- vm_page_unlock(m);
+ }
+ if (mtx != NULL) {
+ mtx_unlock(mtx);
+ mtx = NULL;
+ }
+ if (obj_locked) {
VM_OBJECT_WUNLOCK(object);
-relock_queue:
- if (!queue_locked) {
- vm_pagequeue_lock(pq);
- queue_locked = true;
- }
- next = TAILQ_NEXT(marker, plinks.q);
- TAILQ_REMOVE(&pq->pq_pl, marker, plinks.q);
+ obj_locked = false;
}
+ vm_pagequeue_lock(pq);
+ vm_pageout_end_scan(&ss);
vm_pagequeue_unlock(pq);
if (launder > 0 && queue == PQ_UNSWAPPABLE) {
@@ -1077,6 +1124,56 @@
}
}
+static int
+vm_pageout_reinsert_inactive_page(struct scan_state *ss, vm_page_t m)
+{
+ struct vm_domain *vmd;
+
+ if (!vm_page_inactive(m) || (m->aflags & PGA_ENQUEUED) != 0)
+ return (0);
+ vm_page_aflag_set(m, PGA_ENQUEUED);
+ if ((m->aflags & PGA_REQUEUE_HEAD) != 0) {
+ vmd = vm_pagequeue_domain(m);
+ TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q);
+ vm_page_aflag_clear(m, PGA_REQUEUE | PGA_REQUEUE_HEAD);
+ } else if ((m->aflags & PGA_REQUEUE) != 0) {
+ TAILQ_INSERT_TAIL(&ss->pq->pq_pl, m, plinks.q);
+ vm_page_aflag_clear(m, PGA_REQUEUE | PGA_REQUEUE_HEAD);
+ } else
+ TAILQ_INSERT_BEFORE(ss->marker, m, plinks.q);
+ return (1);
+}
+
+/*
+ * Re-add stuck pages to the inactive queue. We will examine them again
+ * during the next scan. If the queue state of a page has changed since
+ * it was physically removed from the page queue in
+ * vm_pageout_collect_batch(), don't do anything with that page.
+ */
+static void
+vm_pageout_reinsert_inactive(struct scan_state *ss, struct vm_batchqueue *bq,
+ vm_page_t m)
+{
+ struct vm_pagequeue *pq;
+ int delta;
+
+ delta = 0;
+ pq = ss->pq;
+
+ if (m != NULL) {
+ if (vm_batchqueue_insert(bq, m))
+ return;
+ vm_pagequeue_lock(pq);
+ delta += vm_pageout_reinsert_inactive_page(ss, m);
+ } else
+ vm_pagequeue_lock(pq);
+ while ((m = vm_batchqueue_pop(bq)) != NULL)
+ delta += vm_pageout_reinsert_inactive_page(ss, m);
+ vm_pagequeue_cnt_add(pq, delta);
+ vm_pagequeue_unlock(pq);
+ vm_batchqueue_init(bq);
+}
+
/*
* vm_pageout_scan does the dirty work for the pageout daemon.
*
@@ -1089,13 +1186,16 @@
static bool
vm_pageout_scan(struct vm_domain *vmd, int pass, int shortage)
{
- vm_page_t m, marker, next;
+ struct scan_state ss;
+ struct vm_batchqueue rq;
+ struct mtx *mtx;
+ vm_page_t m, marker;
struct vm_pagequeue *pq;
vm_object_t object;
long min_scan;
- int act_delta, addl_page_shortage, deficit, inactq_shortage, maxscan;
- int page_shortage, scan_tick, scanned, starting_page_shortage;
- boolean_t queue_locked;
+ int act_delta, addl_page_shortage, deficit, inactq_shortage, max_scan;
+ int page_shortage, scan_tick, starting_page_shortage;
+ bool obj_locked;
/*
* If we need to reclaim memory ask kernel caches to return
@@ -1136,79 +1236,85 @@
page_shortage = deficit = 0;
starting_page_shortage = page_shortage;
+ mtx = NULL;
+ obj_locked = false;
+ object = NULL;
+ vm_batchqueue_init(&rq);
+
/*
* Start scanning the inactive queue for pages that we can free. The
* scan will stop when we reach the target or we have scanned the
* entire queue. (Note that m->act_count is not used to make
* decisions for the inactive queue, only for the active queue.)
*/
- pq = &vmd->vmd_pagequeues[PQ_INACTIVE];
marker = &vmd->vmd_markers[PQ_INACTIVE];
- maxscan = pq->pq_cnt;
+ pq = &vmd->vmd_pagequeues[PQ_INACTIVE];
vm_pagequeue_lock(pq);
- queue_locked = TRUE;
- for (m = TAILQ_FIRST(&pq->pq_pl);
- m != NULL && maxscan-- > 0 && page_shortage > 0;
- m = next) {
- vm_pagequeue_assert_locked(pq);
- KASSERT(queue_locked, ("unlocked inactive queue"));
- KASSERT(vm_page_inactive(m), ("Inactive queue %p", m));
+ vm_pageout_init_scan(&ss, pq, marker, NULL, pq->pq_cnt);
+ while (page_shortage > 0 && (m = vm_pageout_next(&ss, true)) != NULL) {
+ KASSERT((m->flags & PG_MARKER) == 0,
+ ("marker page %p was dequeued", m));
- VM_CNT_INC(v_pdpages);
- next = TAILQ_NEXT(m, plinks.q);
+ vm_page_change_lock(m, &mtx);
+recheck:
/*
- * skip marker pages
+ * The page may have been disassociated from the queue
+ * while locks were dropped.
*/
- if (m->flags & PG_MARKER)
+ if (!vm_pageout_page_queued(m, PQ_INACTIVE)) {
+ addl_page_shortage++;
continue;
+ }
- KASSERT((m->flags & PG_FICTITIOUS) == 0,
- ("Fictitious page %p cannot be in inactive queue", m));
- KASSERT((m->oflags & VPO_UNMANAGED) == 0,
- ("Unmanaged page %p cannot be in inactive queue", m));
+ /*
+ * The page was re-enqueued after the page queue lock was
+ * dropped, or a requeue was requested. This page gets a second
+ * chance.
+ */
+ if ((m->aflags & (PGA_ENQUEUED | PGA_REQUEUE |
+ PGA_REQUEUE_HEAD)) != 0)
+ goto reinsert;
/*
- * The page or object lock acquisitions fail if the
- * page was removed from the queue or moved to a
- * different position within the queue. In either
- * case, addl_page_shortage should not be incremented.
+ * Held pages are essentially stuck in the queue. So,
+ * they ought to be discounted from the inactive count.
+ * See the calculation of inactq_shortage before the
+ * loop over the active queue below.
+ *
+ * Wired pages may not be freed. Complete their removal
+ * from the queue now to avoid needless revisits during
+ * future scans.
*/
- if (!vm_pageout_page_lock(m, &next))
- goto unlock_page;
- else if (m->wire_count != 0) {
- /*
- * Wired pages may not be freed, and unwiring a queued
- * page will cause it to be requeued. Thus, remove them
- * from the queue now to avoid unnecessary revisits.
- */
- vm_page_dequeue_locked(m);
+ if (m->hold_count != 0) {
addl_page_shortage++;
- goto unlock_page;
- } else if (m->hold_count != 0) {
- /*
- * Held pages are essentially stuck in the
- * queue. So, they ought to be discounted
- * from the inactive count. See the
- * calculation of inactq_shortage before the
- * loop over the active queue below.
- */
+ goto reinsert;
+ }
+ if (m->wire_count != 0) {
addl_page_shortage++;
- goto unlock_page;
+ vm_page_dequeue_deferred(m);
+ continue;
}
- object = m->object;
- if (!VM_OBJECT_TRYWLOCK(object)) {
- if (!vm_pageout_fallback_object_lock(m, &next))
- goto unlock_object;
- else if (m->wire_count != 0) {
- vm_page_dequeue_locked(m);
- addl_page_shortage++;
- goto unlock_object;
- } else if (m->hold_count != 0) {
- addl_page_shortage++;
- goto unlock_object;
+
+ if (object != m->object) {
+ if (obj_locked) {
+ VM_OBJECT_WUNLOCK(object);
+ obj_locked = false;
}
+ object = m->object;
}
+ if (!obj_locked) {
+ if (!VM_OBJECT_TRYWLOCK(object)) {
+ mtx_unlock(mtx);
+ /* Depends on type-stability. */
+ VM_OBJECT_WLOCK(object);
+ obj_locked = true;
+ mtx_lock(mtx);
+ goto recheck;
+ } else
+ obj_locked = true;
+ }
+
if (vm_page_busied(m)) {
/*
* Don't mess with busy pages. Leave them at
@@ -1219,26 +1325,8 @@
* inactive count.
*/
addl_page_shortage++;
-unlock_object:
- VM_OBJECT_WUNLOCK(object);
-unlock_page:
- vm_page_unlock(m);
- continue;
+ goto reinsert;
}
- KASSERT(!vm_page_held(m), ("Held page %p", m));
-
- /*
- * Dequeue the inactive page and unlock the inactive page
- * queue, invalidating the 'next' pointer. Dequeueing the
- * page here avoids a later reacquisition (and release) of
- * the inactive page queue lock when vm_page_activate(),
- * vm_page_free(), or vm_page_launder() is called. Use a
- * marker to remember our place in the inactive queue.
- */
- TAILQ_INSERT_AFTER(&pq->pq_pl, m, marker, plinks.q);
- vm_page_dequeue_locked(m);
- vm_pagequeue_unlock(pq);
- queue_locked = FALSE;
/*
* Invalid pages can be easily freed. They cannot be
@@ -1276,14 +1364,10 @@
* queue.
*/
m->act_count += act_delta + ACT_ADVANCE;
- goto drop_page;
+ continue;
} else if ((object->flags & OBJ_DEAD) == 0) {
- vm_pagequeue_lock(pq);
- queue_locked = TRUE;
- m->queue = PQ_INACTIVE;
- TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q);
- vm_pagequeue_cnt_inc(pq);
- goto drop_page;
+ vm_page_aflag_set(m, PGA_REQUEUE);
+ goto reinsert;
}
}
@@ -1309,23 +1393,39 @@
*/
if (m->dirty == 0) {
free_page:
+ /*
+ * Because we dequeued the page and have already
+ * checked for concurrent dequeue and enqueue
+ * requests, we can safely disassociate the page
+ * from the inactive queue.
+ */
+ KASSERT((m->aflags & PGA_QUEUE_STATE_MASK) == 0,
+ ("page %p has queue state", m));
+ m->queue = PQ_NONE;
vm_page_free(m);
- VM_CNT_INC(v_dfree);
- --page_shortage;
+ page_shortage--;
} else if ((object->flags & OBJ_DEAD) == 0)
vm_page_launder(m);
-drop_page:
- vm_page_unlock(m);
+ continue;
+reinsert:
+ vm_pageout_reinsert_inactive(&ss, &rq, m);
+ }
+ if (mtx != NULL) {
+ mtx_unlock(mtx);
+ mtx = NULL;
+ }
+ if (obj_locked) {
VM_OBJECT_WUNLOCK(object);
- if (!queue_locked) {
- vm_pagequeue_lock(pq);
- queue_locked = TRUE;
- }
- next = TAILQ_NEXT(marker, plinks.q);
- TAILQ_REMOVE(&pq->pq_pl, marker, plinks.q);
+ obj_locked = false;
}
+ vm_pageout_reinsert_inactive(&ss, &rq, NULL);
+ vm_pageout_reinsert_inactive(&ss, &ss.bq, NULL);
+ vm_pagequeue_lock(pq);
+ vm_pageout_end_scan(&ss);
vm_pagequeue_unlock(pq);
+ VM_CNT_ADD(v_dfree, starting_page_shortage - page_shortage);
+
/*
* Wake up the laundry thread so that it can perform any needed
* laundering. If we didn't meet our target, we're in shortfall and
@@ -1386,9 +1486,9 @@
vm_paging_target(vmd) + deficit + addl_page_shortage;
inactq_shortage *= act_scan_laundry_weight;
+ marker = &vmd->vmd_markers[PQ_ACTIVE];
pq = &vmd->vmd_pagequeues[PQ_ACTIVE];
vm_pagequeue_lock(pq);
- maxscan = pq->pq_cnt;
/*
* If we're just idle polling attempt to visit every
@@ -1401,43 +1501,55 @@
min_scan /= hz * vm_pageout_update_period;
} else
min_scan = 0;
- if (min_scan > 0 || (inactq_shortage > 0 && maxscan > 0))
+ if (min_scan > 0 || (inactq_shortage > 0 && pq->pq_cnt > 0))
vmd->vmd_last_active_scan = scan_tick;
/*
* Scan the active queue for pages that can be deactivated. Update
* the per-page activity counter and use it to identify deactivation
* candidates. Held pages may be deactivated.
+ *
+ * To avoid requeuing each page that remains in the active queue, we
+ * implement the CLOCK algorithm. To maintain consistency in the
+ * generic page queue code, pages are inserted at the tail of the
+ * active queue. We thus use two hands, represented by marker pages:
+ * scans begin at the first hand, which precedes the second hand in
+ * the queue. When the two hands meet, they are moved back to the
+ * head and tail of the queue, respectively, and scanning resumes.
*/
- for (m = TAILQ_FIRST(&pq->pq_pl), scanned = 0; m != NULL && (scanned <
- min_scan || (inactq_shortage > 0 && scanned < maxscan)); m = next,
- scanned++) {
- KASSERT(m->queue == PQ_ACTIVE,
- ("vm_pageout_scan: page %p isn't active", m));
- next = TAILQ_NEXT(m, plinks.q);
- if ((m->flags & PG_MARKER) != 0)
- continue;
- KASSERT((m->flags & PG_FICTITIOUS) == 0,
- ("Fictitious page %p cannot be in active queue", m));
- KASSERT((m->oflags & VPO_UNMANAGED) == 0,
- ("Unmanaged page %p cannot be in active queue", m));
- if (!vm_pageout_page_lock(m, &next)) {
- vm_page_unlock(m);
- continue;
+ max_scan = inactq_shortage > 0 ? pq->pq_cnt : min_scan;
+act_scan:
+ vm_pageout_init_scan(&ss, pq, marker, &vmd->vmd_clock[0], max_scan);
+ while ((m = vm_pageout_next(&ss, false)) != NULL) {
+ if (__predict_false(m == &vmd->vmd_clock[1])) {
+ vm_pagequeue_lock(pq);
+ TAILQ_REMOVE(&pq->pq_pl, &vmd->vmd_clock[0], plinks.q);
+ TAILQ_REMOVE(&pq->pq_pl, &vmd->vmd_clock[1], plinks.q);
+ TAILQ_INSERT_HEAD(&pq->pq_pl, &vmd->vmd_clock[0],
+ plinks.q);
+ TAILQ_INSERT_TAIL(&pq->pq_pl, &vmd->vmd_clock[1],
+ plinks.q);
+ max_scan -= ss.scanned;
+ vm_pageout_end_scan(&ss);
+ goto act_scan;
}
+ if (__predict_false((m->flags & PG_MARKER) != 0))
+ continue;
+
+ vm_page_change_lock(m, &mtx);
/*
- * The count for page daemon pages is updated after checking
- * the page for eligibility.
+ * The page may have been disassociated from the queue
+ * while locks were dropped.
*/
- VM_CNT_INC(v_pdpages);
+ if (!vm_pageout_page_queued(m, PQ_ACTIVE))
+ continue;
/*
* Wired pages are dequeued lazily.
*/
if (m->wire_count != 0) {
- vm_page_dequeue_locked(m);
- vm_page_unlock(m);
+ vm_page_dequeue_deferred(m);
continue;
}
@@ -1476,14 +1588,7 @@
} else
m->act_count -= min(m->act_count, ACT_DECLINE);
- /*
- * Move this page to the tail of the active, inactive or laundry
- * queue depending on usage.
- */
if (m->act_count == 0) {
- /* Dequeue to avoid later lock recursion. */
- vm_page_dequeue_locked(m);
-
/*
* When not short for inactive pages, let dirty pages go
* through the inactive queue before moving to the
@@ -1515,11 +1620,18 @@
inactq_shortage--;
}
}
- } else
- vm_page_requeue_locked(m);
- vm_page_unlock(m);
+ }
+ }
+ if (mtx != NULL) {
+ mtx_unlock(mtx);
+ mtx = NULL;
}
+ vm_pagequeue_lock(pq);
+ TAILQ_REMOVE(&pq->pq_pl, &vmd->vmd_clock[0], plinks.q);
+ TAILQ_INSERT_AFTER(&pq->pq_pl, marker, &vmd->vmd_clock[0], plinks.q);
+ vm_pageout_end_scan(&ss);
vm_pagequeue_unlock(pq);
+
if (pass > 0)
vm_swapout_run_idle();
return (page_shortage <= 0);
Index: sys/vm/vm_pagequeue.h
===================================================================
--- sys/vm/vm_pagequeue.h
+++ sys/vm/vm_pagequeue.h
@@ -73,8 +73,17 @@
const char * const pq_name;
} __aligned(CACHE_LINE_SIZE);
-#include <sys/pidctrl.h>
+#ifndef VM_BATCHQUEUE_SIZE
+#define VM_BATCHQUEUE_SIZE 7
+#endif
+
+struct vm_batchqueue {
+ vm_page_t bq_pa[VM_BATCHQUEUE_SIZE];
+ int bq_cnt;
+} __aligned(CACHE_LINE_SIZE);
+
#include <vm/uma.h>
+#include <sys/pidctrl.h>
struct sysctl_oid;
/*
@@ -82,12 +91,12 @@
* and accounting.
*
* Lock Key:
- * f vmd_free_mtx
- * p vmd_pageout_mtx
- * d vm_domainset_lock
- * a atomic
- * c const after boot
- * q page queue lock
+ * f vmd_free_mtx
+ * p vmd_pageout_mtx
+ * d vm_domainset_lock
+ * a atomic
+ * c const after boot
+ * q page queue lock
*/
struct vm_domain {
struct vm_pagequeue vmd_pagequeues[PQ_COUNT];
@@ -107,8 +116,9 @@
boolean_t vmd_oom;
int vmd_oom_seq;
int vmd_last_active_scan;
- struct vm_page vmd_markers[PQ_COUNT]; /* markers for queue scans */
+ struct vm_page vmd_markers[PQ_COUNT]; /* (q) markers for queue scans */
struct vm_page vmd_inacthead; /* marker for LRU-defeating insertions */
+ struct vm_page vmd_clock[2]; /* markers for active queue scan */
int vmd_pageout_wanted; /* (a, p) pageout daemon wait channel */
int vmd_pageout_pages_needed; /* (d) page daemon waiting for pages? */
@@ -144,6 +154,7 @@
#define vm_pagequeue_assert_locked(pq) mtx_assert(&(pq)->pq_mutex, MA_OWNED)
#define vm_pagequeue_lock(pq) mtx_lock(&(pq)->pq_mutex)
#define vm_pagequeue_lockptr(pq) (&(pq)->pq_mutex)
+#define vm_pagequeue_trylock(pq) mtx_trylock(&(pq)->pq_mutex)
#define vm_pagequeue_unlock(pq) mtx_unlock(&(pq)->pq_mutex)
#define vm_domain_free_assert_locked(n) \
@@ -154,6 +165,8 @@
mtx_lock(vm_domain_free_lockptr((d)))
#define vm_domain_free_lockptr(d) \
(&(d)->vmd_free_mtx)
+#define vm_domain_free_trylock(d) \
+ mtx_trylock(vm_domain_free_lockptr((d)))
#define vm_domain_free_unlock(d) \
mtx_unlock(vm_domain_free_lockptr((d)))
@@ -172,14 +185,39 @@
vm_pagequeue_cnt_add(struct vm_pagequeue *pq, int addend)
{
-#ifdef notyet
vm_pagequeue_assert_locked(pq);
-#endif
pq->pq_cnt += addend;
}
#define vm_pagequeue_cnt_inc(pq) vm_pagequeue_cnt_add((pq), 1)
#define vm_pagequeue_cnt_dec(pq) vm_pagequeue_cnt_add((pq), -1)
+static inline void
+vm_batchqueue_init(struct vm_batchqueue *bq)
+{
+
+ bq->bq_cnt = 0;
+}
+
+static inline bool
+vm_batchqueue_insert(struct vm_batchqueue *bq, vm_page_t m)
+{
+
+ if (bq->bq_cnt < nitems(bq->bq_pa)) {
+ bq->bq_pa[bq->bq_cnt++] = m;
+ return (true);
+ }
+ return (false);
+}
+
+static inline vm_page_t
+vm_batchqueue_pop(struct vm_batchqueue *bq)
+{
+
+ if (bq->bq_cnt == 0)
+ return (NULL);
+ return (bq->bq_pa[--bq->bq_cnt]);
+}
+
void vm_domain_set(struct vm_domain *vmd);
void vm_domain_clear(struct vm_domain *vmd);
int vm_domain_allocate(struct vm_domain *vmd, int req, int npages);
Index: sys/vm/vm_phys.c
===================================================================
--- sys/vm/vm_phys.c
+++ sys/vm/vm_phys.c
@@ -354,9 +354,9 @@
m->order = order;
if (tail)
- TAILQ_INSERT_TAIL(&fl[order].pl, m, plinks.q);
+ TAILQ_INSERT_TAIL(&fl[order].pl, m, listq);
else
- TAILQ_INSERT_HEAD(&fl[order].pl, m, plinks.q);
+ TAILQ_INSERT_HEAD(&fl[order].pl, m, listq);
fl[order].lcnt++;
}
@@ -364,7 +364,7 @@
vm_freelist_rem(struct vm_freelist *fl, vm_page_t m, int order)
{
- TAILQ_REMOVE(&fl[order].pl, m, plinks.q);
+ TAILQ_REMOVE(&fl[order].pl, m, listq);
fl[order].lcnt--;
m->order = VM_NFREEORDER;
}
@@ -1196,7 +1196,7 @@
oind++) {
for (pind = 0; pind < VM_NFREEPOOL; pind++) {
fl = (*seg->free_queues)[pind];
- TAILQ_FOREACH(m_ret, &fl[oind].pl, plinks.q) {
+ TAILQ_FOREACH(m_ret, &fl[oind].pl, listq) {
/*
* Is the size of this allocation request
* larger than the largest block size?
Index: sys/vm/vm_swapout.c
===================================================================
--- sys/vm/vm_swapout.c
+++ sys/vm/vm_swapout.c
@@ -399,8 +399,15 @@
swapout_flags = vm_pageout_req_swapout;
vm_pageout_req_swapout = 0;
mtx_unlock(&vm_daemon_mtx);
- if (swapout_flags)
+ if (swapout_flags != 0) {
+ /*
+ * Drain the per-CPU page queue batches as a deadlock
+ * avoidance measure.
+ */
+ if ((swapout_flags & VM_SWAP_NORMAL) != 0)
+ vm_page_drain_pqbatch();
swapout_procs(swapout_flags);
+ }
/*
* scan the processes for exceeding their rlimits or if

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