svn commit: r189075 - in stable/7: lib/libc lib/libc/string
lib/libc/sys share/man/man9 sys sys/amd64/amd64
sys/amd64/include sys/arm/arm sys/arm/include sys/conf
sys/contrib/pf sys/dev/ath/ath_hal...
John Baldwin
jhb at FreeBSD.org
Thu Feb 26 11:42:06 PST 2009
Author: jhb
Date: Thu Feb 26 15:59:22 2009
New Revision: 189075
URL: http://svn.freebsd.org/changeset/base/189075
Log:
MFC: Add support for "superpages" on amd64 and i386. This includes adding the
superpage reservation system to the machine-independent VM system as well as
changes to the pmap code for amd64 and i386 to support superpages.
Reviewed by: alc
Tested by: ps
Added:
stable/7/sys/vm/vm_reserv.c
- copied, changed from r174982, head/sys/vm/vm_reserv.c
stable/7/sys/vm/vm_reserv.h
- copied, changed from r174982, head/sys/vm/vm_reserv.h
Deleted:
stable/7/sys/vm/vm_pageq.c
Modified:
stable/7/lib/libc/ (props changed)
stable/7/lib/libc/string/ffsll.c (props changed)
stable/7/lib/libc/string/flsll.c (props changed)
stable/7/lib/libc/sys/mincore.2
stable/7/share/man/man9/ (props changed)
stable/7/share/man/man9/vm_map_find.9
stable/7/sys/ (props changed)
stable/7/sys/amd64/amd64/pmap.c
stable/7/sys/amd64/include/pmap.h
stable/7/sys/amd64/include/vmparam.h
stable/7/sys/arm/arm/pmap.c
stable/7/sys/arm/include/vmparam.h
stable/7/sys/conf/files
stable/7/sys/conf/options
stable/7/sys/contrib/pf/ (props changed)
stable/7/sys/dev/ath/ath_hal/ (props changed)
stable/7/sys/dev/cxgb/ (props changed)
stable/7/sys/i386/i386/pmap.c
stable/7/sys/i386/include/pmap.h
stable/7/sys/i386/include/vmparam.h
stable/7/sys/ia64/ia64/pmap.c
stable/7/sys/ia64/include/vmparam.h
stable/7/sys/kern/kern_exec.c
stable/7/sys/kern/kern_malloc.c
stable/7/sys/powerpc/include/vmparam.h
stable/7/sys/powerpc/powerpc/pmap_dispatch.c
stable/7/sys/sparc64/include/vmparam.h
stable/7/sys/sparc64/sparc64/pmap.c
stable/7/sys/sun4v/include/vmparam.h
stable/7/sys/sun4v/sun4v/pmap.c
stable/7/sys/sys/mman.h
stable/7/sys/vm/device_pager.c
stable/7/sys/vm/memguard.c
stable/7/sys/vm/pmap.h
stable/7/sys/vm/vm.h
stable/7/sys/vm/vm_extern.h
stable/7/sys/vm/vm_fault.c
stable/7/sys/vm/vm_init.c
stable/7/sys/vm/vm_kern.c
stable/7/sys/vm/vm_map.c
stable/7/sys/vm/vm_map.h
stable/7/sys/vm/vm_mmap.c
stable/7/sys/vm/vm_object.c
stable/7/sys/vm/vm_object.h
stable/7/sys/vm/vm_page.c
stable/7/sys/vm/vm_page.h
stable/7/sys/vm/vm_pageout.c
stable/7/sys/vm/vm_phys.c
stable/7/sys/vm/vm_phys.h
stable/7/sys/vm/vnode_pager.c
Modified: stable/7/lib/libc/sys/mincore.2
==============================================================================
--- stable/7/lib/libc/sys/mincore.2 Thu Feb 26 15:51:54 2009 (r189074)
+++ stable/7/lib/libc/sys/mincore.2 Thu Feb 26 15:59:22 2009 (r189075)
@@ -72,6 +72,8 @@ Page has been modified by us.
Page has been referenced.
.It Dv MINCORE_MODIFIED_OTHER
Page has been modified.
+.It Dv MINCORE_SUPER
+Page is part of a "super" page. (only i386 & amd64)
.El
.Pp
The information returned by
Modified: stable/7/share/man/man9/vm_map_find.9
==============================================================================
--- stable/7/share/man/man9/vm_map_find.9 Thu Feb 26 15:51:54 2009 (r189074)
+++ stable/7/share/man/man9/vm_map_find.9 Thu Feb 26 15:59:22 2009 (r189075)
@@ -25,7 +25,7 @@
.\"
.\" $FreeBSD$
.\"
-.Dd July 19, 2003
+.Dd May 10, 2008
.Dt VM_MAP_FIND 9
.Os
.Sh NAME
@@ -38,7 +38,7 @@
.Ft int
.Fo vm_map_find
.Fa "vm_map_t map" "vm_object_t object" "vm_ooffset_t offset"
-.Fa "vm_offset_t *addr" "vm_size_t length" "boolean_t find_space"
+.Fa "vm_offset_t *addr" "vm_size_t length" "int find_space"
.Fa "vm_prot_t prot" "vm_prot_t max" "int cow"
.Fc
.Sh DESCRIPTION
@@ -70,11 +70,25 @@ by the caller before calling this functi
.Pp
If
.Fa find_space
-is
-.Dv TRUE ,
+is either
+.Dv VMFS_ALIGNED_SPACE
+or
+.Dv VMFS_ANY_SPACE ,
the function will call
.Xr vm_map_findspace 9
to discover a free region.
+Moreover, if
+.Fa find_space
+is
+.Dv VMFS_ALIGNED_SPACE ,
+the address of the free region will be optimized for the use of superpages.
+Otherwise, if
+.Fa find_space
+is
+.Dv VMFS_NO_SPACE ,
+.Xr vm_map_insert 9
+is called with the given address,
+.Fa addr .
.Sh IMPLEMENTATION NOTES
This function acquires a lock on
.Fa map
@@ -90,9 +104,14 @@ The
.Fn vm_map_find
function returns
.Dv KERN_SUCCESS
-if space for the mapping could be found and
-the mapping was successfully created.
-If space could not be found in the map,
+if the mapping was successfully created.
+If space could not be found or
+.Fa find_space
+was
+.Dv VMFS_NO_SPACE
+and the given address,
+.Fa addr ,
+was already mapped,
.Dv KERN_NO_SPACE
will be returned.
If the discovered range turned out to be bogus,
Modified: stable/7/sys/amd64/amd64/pmap.c
==============================================================================
--- stable/7/sys/amd64/amd64/pmap.c Thu Feb 26 15:51:54 2009 (r189074)
+++ stable/7/sys/amd64/amd64/pmap.c Thu Feb 26 15:59:22 2009 (r189075)
@@ -7,7 +7,7 @@
* All rights reserved.
* Copyright (c) 2003 Peter Wemm
* All rights reserved.
- * Copyright (c) 2005 Alan L. Cox <alc at cs.rice.edu>
+ * Copyright (c) 2005-2008 Alan L. Cox <alc at cs.rice.edu>
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
@@ -107,10 +107,12 @@ __FBSDID("$FreeBSD$");
#include "opt_msgbuf.h"
#include "opt_pmap.h"
+#include "opt_vm.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
+#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mman.h>
@@ -134,6 +136,7 @@ __FBSDID("$FreeBSD$");
#include <vm/vm_extern.h>
#include <vm/vm_pageout.h>
#include <vm/vm_pager.h>
+#include <vm/vm_reserv.h>
#include <vm/uma.h>
#include <machine/cpu.h>
@@ -149,11 +152,7 @@ __FBSDID("$FreeBSD$");
#define PMAP_SHPGPERPROC 200
#endif
-#if defined(DIAGNOSTIC)
-#define PMAP_DIAGNOSTIC
-#endif
-
-#if !defined(PMAP_DIAGNOSTIC)
+#if !defined(DIAGNOSTIC)
#define PMAP_INLINE __gnu89_inline
#else
#define PMAP_INLINE
@@ -166,6 +165,9 @@ __FBSDID("$FreeBSD$");
#define PV_STAT(x) do { } while (0)
#endif
+#define pa_index(pa) ((pa) >> PDRSHIFT)
+#define pa_to_pvh(pa) (&pv_table[pa_index(pa)])
+
struct pmap kernel_pmap_store;
vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */
@@ -176,6 +178,12 @@ static vm_paddr_t dmaplimit;
vm_offset_t kernel_vm_end = VM_MIN_KERNEL_ADDRESS;
pt_entry_t pg_nx;
+SYSCTL_NODE(_vm, OID_AUTO, pmap, CTLFLAG_RD, 0, "VM/pmap parameters");
+
+static int pg_ps_enabled;
+SYSCTL_INT(_vm_pmap, OID_AUTO, pg_ps_enabled, CTLFLAG_RD, &pg_ps_enabled, 0,
+ "Are large page mappings enabled?");
+
static u_int64_t KPTphys; /* phys addr of kernel level 1 */
static u_int64_t KPDphys; /* phys addr of kernel level 2 */
u_int64_t KPDPphys; /* phys addr of kernel level 3 */
@@ -188,6 +196,7 @@ static u_int64_t DMPDPphys; /* phys addr
* Data for the pv entry allocation mechanism
*/
static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0;
+static struct md_page *pv_table;
static int shpgperproc = PMAP_SHPGPERPROC;
/*
@@ -204,11 +213,29 @@ static caddr_t crashdumpmap;
static void free_pv_entry(pmap_t pmap, pv_entry_t pv);
static pv_entry_t get_pv_entry(pmap_t locked_pmap, int try);
-
+static void pmap_pv_demote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
+static boolean_t pmap_pv_insert_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
+static void pmap_pv_promote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa);
+static void pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va);
+static pv_entry_t pmap_pvh_remove(struct md_page *pvh, pmap_t pmap,
+ vm_offset_t va);
+
+static boolean_t pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va);
+static boolean_t pmap_enter_pde(pmap_t pmap, vm_offset_t va, vm_page_t m,
+ vm_prot_t prot);
static vm_page_t pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va,
vm_page_t m, vm_prot_t prot, vm_page_t mpte);
+static void pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte);
+static boolean_t pmap_is_modified_pvh(struct md_page *pvh);
+static vm_page_t pmap_lookup_pt_page(pmap_t pmap, vm_offset_t va);
+static void pmap_promote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va);
+static boolean_t pmap_protect_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t sva,
+ vm_prot_t prot);
+static int pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
+ vm_page_t *free);
static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq,
vm_offset_t sva, pd_entry_t ptepde, vm_page_t *free);
+static void pmap_remove_pt_page(pmap_t pmap, vm_page_t mpte);
static void pmap_remove_page(pmap_t pmap, vm_offset_t va, pd_entry_t *pde,
vm_page_t *free);
static void pmap_remove_entry(struct pmap *pmap, vm_page_t m,
@@ -362,21 +389,6 @@ pmap_pte(pmap_t pmap, vm_offset_t va)
}
-static __inline pt_entry_t *
-pmap_pte_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *ptepde)
-{
- pd_entry_t *pde;
-
- pde = pmap_pde(pmap, va);
- if (pde == NULL || (*pde & PG_V) == 0)
- return NULL;
- *ptepde = *pde;
- if ((*pde & PG_PS) != 0) /* compat with i386 pmap_pte() */
- return ((pt_entry_t *)pde);
- return (pmap_pde_to_pte(pde, va));
-}
-
-
PMAP_INLINE pt_entry_t *
vtopte(vm_offset_t va)
{
@@ -511,6 +523,7 @@ pmap_bootstrap(vm_paddr_t *firstaddr)
*/
PMAP_LOCK_INIT(kernel_pmap);
kernel_pmap->pm_pml4 = (pdp_entry_t *) (KERNBASE + KPML4phys);
+ kernel_pmap->pm_root = NULL;
kernel_pmap->pm_active = -1; /* don't allow deactivation */
TAILQ_INIT(&kernel_pmap->pm_pvchunk);
@@ -609,6 +622,26 @@ pmap_page_init(vm_page_t m)
void
pmap_init(void)
{
+ pd_entry_t *pd;
+ vm_page_t mpte;
+ vm_size_t s;
+ int i, pv_npg;
+
+ /*
+ * Initialize the vm page array entries for the kernel pmap's
+ * page table pages.
+ */
+ pd = pmap_pde(kernel_pmap, VM_MIN_KERNEL_ADDRESS);
+ for (i = 0; i < NKPT; i++) {
+ if ((pd[i] & (PG_PS | PG_V)) == (PG_PS | PG_V))
+ continue;
+ mpte = PHYS_TO_VM_PAGE(pd[i] & PG_FRAME);
+ KASSERT(mpte >= vm_page_array &&
+ mpte < &vm_page_array[vm_page_array_size],
+ ("pmap_init: page table page is out of range"));
+ mpte->pindex = pmap_pde_pindex(VM_MIN_KERNEL_ADDRESS) + i;
+ mpte->phys_addr = pd[i] & PG_FRAME;
+ }
/*
* Initialize the address space (zone) for the pv entries. Set a
@@ -619,9 +652,28 @@ pmap_init(void)
pv_entry_max = shpgperproc * maxproc + cnt.v_page_count;
TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
pv_entry_high_water = 9 * (pv_entry_max / 10);
+
+ /*
+ * Are large page mappings enabled?
+ */
+ TUNABLE_INT_FETCH("vm.pmap.pg_ps_enabled", &pg_ps_enabled);
+
+ /*
+ * Calculate the size of the pv head table for superpages.
+ */
+ for (i = 0; phys_avail[i + 1]; i += 2);
+ pv_npg = round_2mpage(phys_avail[(i - 2) + 1]) / NBPDR;
+
+ /*
+ * Allocate memory for the pv head table for superpages.
+ */
+ s = (vm_size_t)(pv_npg * sizeof(struct md_page));
+ s = round_page(s);
+ pv_table = (struct md_page *)kmem_alloc(kernel_map, s);
+ for (i = 0; i < pv_npg; i++)
+ TAILQ_INIT(&pv_table[i].pv_list);
}
-SYSCTL_NODE(_vm, OID_AUTO, pmap, CTLFLAG_RD, 0, "VM/pmap parameters");
static int
pmap_pventry_proc(SYSCTL_HANDLER_ARGS)
{
@@ -652,6 +704,25 @@ pmap_shpgperproc_proc(SYSCTL_HANDLER_ARG
SYSCTL_PROC(_vm_pmap, OID_AUTO, shpgperproc, CTLTYPE_INT|CTLFLAG_RW,
&shpgperproc, 0, pmap_shpgperproc_proc, "IU", "Page share factor per proc");
+SYSCTL_NODE(_vm_pmap, OID_AUTO, pde, CTLFLAG_RD, 0,
+ "2MB page mapping counters");
+
+static u_long pmap_pde_demotions;
+SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, demotions, CTLFLAG_RD,
+ &pmap_pde_demotions, 0, "2MB page demotions");
+
+static u_long pmap_pde_mappings;
+SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, mappings, CTLFLAG_RD,
+ &pmap_pde_mappings, 0, "2MB page mappings");
+
+static u_long pmap_pde_p_failures;
+SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, p_failures, CTLFLAG_RD,
+ &pmap_pde_p_failures, 0, "2MB page promotion failures");
+
+static u_long pmap_pde_promotions;
+SYSCTL_ULONG(_vm_pmap_pde, OID_AUTO, promotions, CTLFLAG_RD,
+ &pmap_pde_promotions, 0, "2MB page promotions");
+
/***************************************************
* Low level helper routines.....
@@ -953,17 +1024,25 @@ pmap_extract_and_hold(pmap_t pmap, vm_of
vm_paddr_t
pmap_kextract(vm_offset_t va)
{
- pd_entry_t *pde;
+ pd_entry_t pde;
vm_paddr_t pa;
if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) {
pa = DMAP_TO_PHYS(va);
} else {
- pde = vtopde(va);
- if (*pde & PG_PS) {
- pa = (*pde & PG_PS_FRAME) | (va & PDRMASK);
+ pde = *vtopde(va);
+ if (pde & PG_PS) {
+ pa = (pde & PG_PS_FRAME) | (va & PDRMASK);
} else {
- pa = *vtopte(va);
+ /*
+ * Beware of a concurrent promotion that changes the
+ * PDE at this point! For example, vtopte() must not
+ * be used to access the PTE because it would use the
+ * new PDE. It is, however, safe to use the old PDE
+ * because the page table page is preserved by the
+ * promotion.
+ */
+ pa = *pmap_pde_to_pte(&pde, va);
pa = (pa & PG_FRAME) | (va & PAGE_MASK);
}
}
@@ -1085,8 +1164,105 @@ pmap_free_zero_pages(vm_page_t free)
while (free != NULL) {
m = free;
free = m->right;
- vm_page_free_zero(m);
+ /* Preserve the page's PG_ZERO setting. */
+ vm_page_free_toq(m);
+ }
+}
+
+/*
+ * Schedule the specified unused page table page to be freed. Specifically,
+ * add the page to the specified list of pages that will be released to the
+ * physical memory manager after the TLB has been updated.
+ */
+static __inline void
+pmap_add_delayed_free_list(vm_page_t m, vm_page_t *free, boolean_t set_PG_ZERO)
+{
+
+ if (set_PG_ZERO)
+ m->flags |= PG_ZERO;
+ else
+ m->flags &= ~PG_ZERO;
+ m->right = *free;
+ *free = m;
+}
+
+/*
+ * Inserts the specified page table page into the specified pmap's collection
+ * of idle page table pages. Each of a pmap's page table pages is responsible
+ * for mapping a distinct range of virtual addresses. The pmap's collection is
+ * ordered by this virtual address range.
+ */
+static void
+pmap_insert_pt_page(pmap_t pmap, vm_page_t mpte)
+{
+ vm_page_t root;
+
+ PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+ root = pmap->pm_root;
+ if (root == NULL) {
+ mpte->left = NULL;
+ mpte->right = NULL;
+ } else {
+ root = vm_page_splay(mpte->pindex, root);
+ if (mpte->pindex < root->pindex) {
+ mpte->left = root->left;
+ mpte->right = root;
+ root->left = NULL;
+ } else if (mpte->pindex == root->pindex)
+ panic("pmap_insert_pt_page: pindex already inserted");
+ else {
+ mpte->right = root->right;
+ mpte->left = root;
+ root->right = NULL;
+ }
+ }
+ pmap->pm_root = mpte;
+}
+
+/*
+ * Looks for a page table page mapping the specified virtual address in the
+ * specified pmap's collection of idle page table pages. Returns NULL if there
+ * is no page table page corresponding to the specified virtual address.
+ */
+static vm_page_t
+pmap_lookup_pt_page(pmap_t pmap, vm_offset_t va)
+{
+ vm_page_t mpte;
+ vm_pindex_t pindex = pmap_pde_pindex(va);
+
+ PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+ if ((mpte = pmap->pm_root) != NULL && mpte->pindex != pindex) {
+ mpte = vm_page_splay(pindex, mpte);
+ if ((pmap->pm_root = mpte)->pindex != pindex)
+ mpte = NULL;
}
+ return (mpte);
+}
+
+/*
+ * Removes the specified page table page from the specified pmap's collection
+ * of idle page table pages. The specified page table page must be a member of
+ * the pmap's collection.
+ */
+static void
+pmap_remove_pt_page(pmap_t pmap, vm_page_t mpte)
+{
+ vm_page_t root;
+
+ PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+ if (mpte != pmap->pm_root) {
+ root = vm_page_splay(mpte->pindex, pmap->pm_root);
+ KASSERT(mpte == root,
+ ("pmap_remove_pt_page: mpte %p is missing from pmap %p",
+ mpte, pmap));
+ }
+ if (mpte->left == NULL)
+ root = mpte->right;
+ else {
+ root = vm_page_splay(mpte->pindex, mpte->left);
+ root->right = mpte->right;
+ }
+ pmap->pm_root = root;
}
/*
@@ -1165,8 +1341,7 @@ _pmap_unwire_pte_hold(pmap_t pmap, vm_of
* Put page on a list so that it is released after
* *ALL* TLB shootdown is done
*/
- m->right = *free;
- *free = m;
+ pmap_add_delayed_free_list(m, free, TRUE);
return 1;
}
@@ -1193,6 +1368,7 @@ pmap_pinit0(pmap_t pmap)
PMAP_LOCK_INIT(pmap);
pmap->pm_pml4 = (pml4_entry_t *)(KERNBASE + KPML4phys);
+ pmap->pm_root = NULL;
pmap->pm_active = 0;
TAILQ_INIT(&pmap->pm_pvchunk);
bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
@@ -1229,6 +1405,7 @@ pmap_pinit(pmap_t pmap)
/* install self-referential address mapping entry(s) */
pmap->pm_pml4[PML4PML4I] = VM_PAGE_TO_PHYS(pml4pg) | PG_V | PG_RW | PG_A | PG_M;
+ pmap->pm_root = NULL;
pmap->pm_active = 0;
TAILQ_INIT(&pmap->pm_pvchunk);
bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
@@ -1404,7 +1581,7 @@ pmap_allocpte(pmap_t pmap, vm_offset_t v
{
vm_pindex_t ptepindex;
pd_entry_t *pd;
- vm_page_t m, free;
+ vm_page_t m;
KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
(flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
@@ -1424,21 +1601,21 @@ retry:
* This supports switching from a 2MB page to a
* normal 4K page.
*/
- if (pd != 0 && (*pd & (PG_PS | PG_V)) == (PG_PS | PG_V)) {
- *pd = 0;
- pd = 0;
- pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
- free = NULL;
- pmap_unuse_pt(pmap, va, *pmap_pdpe(pmap, va), &free);
- pmap_invalidate_all(kernel_pmap);
- pmap_free_zero_pages(free);
+ if (pd != NULL && (*pd & (PG_PS | PG_V)) == (PG_PS | PG_V)) {
+ if (!pmap_demote_pde(pmap, pd, va)) {
+ /*
+ * Invalidation of the 2MB page mapping may have caused
+ * the deallocation of the underlying PD page.
+ */
+ pd = NULL;
+ }
}
/*
* If the page table page is mapped, we just increment the
* hold count, and activate it.
*/
- if (pd != 0 && (*pd & PG_V) != 0) {
+ if (pd != NULL && (*pd & PG_V) != 0) {
m = PHYS_TO_VM_PAGE(*pd & PG_FRAME);
m->wire_count++;
} else {
@@ -1471,6 +1648,8 @@ pmap_release(pmap_t pmap)
KASSERT(pmap->pm_stats.resident_count == 0,
("pmap_release: pmap resident count %ld != 0",
pmap->pm_stats.resident_count));
+ KASSERT(pmap->pm_root == NULL,
+ ("pmap_release: pmap has reserved page table page(s)"));
m = PHYS_TO_VM_PAGE(pmap->pm_pml4[PML4PML4I] & PG_FRAME);
@@ -1645,11 +1824,16 @@ SYSCTL_INT(_vm_pmap, OID_AUTO, pmap_coll
* drastic measures to free some pages so we can allocate
* another pv entry chunk. This is normally called to
* unmap inactive pages, and if necessary, active pages.
+ *
+ * We do not, however, unmap 2mpages because subsequent accesses will
+ * allocate per-page pv entries until repromotion occurs, thereby
+ * exacerbating the shortage of free pv entries.
*/
static void
pmap_collect(pmap_t locked_pmap, struct vpgqueues *vpq)
{
- pd_entry_t ptepde;
+ struct md_page *pvh;
+ pd_entry_t *pde;
pmap_t pmap;
pt_entry_t *pte, tpte;
pv_entry_t next_pv, pv;
@@ -1668,28 +1852,27 @@ pmap_collect(pmap_t locked_pmap, struct
else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap))
continue;
pmap->pm_stats.resident_count--;
- pte = pmap_pte_pde(pmap, va, &ptepde);
- if (pte == NULL) {
- panic("null pte in pmap_collect");
- }
+ pde = pmap_pde(pmap, va);
+ KASSERT((*pde & PG_PS) == 0, ("pmap_collect: found"
+ " a 2mpage in page %p's pv list", m));
+ pte = pmap_pde_to_pte(pde, va);
tpte = pte_load_clear(pte);
KASSERT((tpte & PG_W) == 0,
("pmap_collect: wired pte %#lx", tpte));
if (tpte & PG_A)
vm_page_flag_set(m, PG_REFERENCED);
- if (tpte & PG_M) {
- KASSERT((tpte & PG_RW),
- ("pmap_collect: modified page not writable: va: %#lx, pte: %#lx",
- va, tpte));
+ if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
- }
free = NULL;
- pmap_unuse_pt(pmap, va, ptepde, &free);
+ pmap_unuse_pt(pmap, va, *pde, &free);
pmap_invalidate_page(pmap, va);
pmap_free_zero_pages(free);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
- if (TAILQ_EMPTY(&m->md.pv_list))
- vm_page_flag_clear(m, PG_WRITEABLE);
+ if (TAILQ_EMPTY(&m->md.pv_list)) {
+ pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
+ if (TAILQ_EMPTY(&pvh->pv_list))
+ vm_page_flag_clear(m, PG_WRITEABLE);
+ }
free_pv_entry(pmap, pv);
if (pmap != locked_pmap)
PMAP_UNLOCK(pmap);
@@ -1824,24 +2007,133 @@ retry:
return (pv);
}
-static void
-pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va)
+/*
+ * First find and then remove the pv entry for the specified pmap and virtual
+ * address from the specified pv list. Returns the pv entry if found and NULL
+ * otherwise. This operation can be performed on pv lists for either 4KB or
+ * 2MB page mappings.
+ */
+static __inline pv_entry_t
+pmap_pvh_remove(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
{
pv_entry_t pv;
- PMAP_LOCK_ASSERT(pmap, MA_OWNED);
mtx_assert(&vm_page_queue_mtx, MA_OWNED);
- TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
- if (pmap == PV_PMAP(pv) && va == pv->pv_va)
+ TAILQ_FOREACH(pv, &pvh->pv_list, pv_list) {
+ if (pmap == PV_PMAP(pv) && va == pv->pv_va) {
+ TAILQ_REMOVE(&pvh->pv_list, pv, pv_list);
break;
+ }
}
- KASSERT(pv != NULL, ("pmap_remove_entry: pv not found"));
- TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
- if (TAILQ_EMPTY(&m->md.pv_list))
- vm_page_flag_clear(m, PG_WRITEABLE);
+ return (pv);
+}
+
+/*
+ * After demotion from a 2MB page mapping to 512 4KB page mappings,
+ * destroy the pv entry for the 2MB page mapping and reinstantiate the pv
+ * entries for each of the 4KB page mappings.
+ */
+static void
+pmap_pv_demote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
+{
+ struct md_page *pvh;
+ pv_entry_t pv;
+ vm_offset_t va_last;
+ vm_page_t m;
+
+ mtx_assert(&vm_page_queue_mtx, MA_OWNED);
+ KASSERT((pa & PDRMASK) == 0,
+ ("pmap_pv_demote_pde: pa is not 2mpage aligned"));
+
+ /*
+ * Transfer the 2mpage's pv entry for this mapping to the first
+ * page's pv list.
+ */
+ pvh = pa_to_pvh(pa);
+ va = trunc_2mpage(va);
+ pv = pmap_pvh_remove(pvh, pmap, va);
+ KASSERT(pv != NULL, ("pmap_pv_demote_pde: pv not found"));
+ m = PHYS_TO_VM_PAGE(pa);
+ TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
+ /* Instantiate the remaining NPTEPG - 1 pv entries. */
+ va_last = va + NBPDR - PAGE_SIZE;
+ do {
+ m++;
+ KASSERT((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0,
+ ("pmap_pv_demote_pde: page %p is not managed", m));
+ va += PAGE_SIZE;
+ pmap_insert_entry(pmap, va, m);
+ } while (va < va_last);
+}
+
+/*
+ * After promotion from 512 4KB page mappings to a single 2MB page mapping,
+ * replace the many pv entries for the 4KB page mappings by a single pv entry
+ * for the 2MB page mapping.
+ */
+static void
+pmap_pv_promote_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
+{
+ struct md_page *pvh;
+ pv_entry_t pv;
+ vm_offset_t va_last;
+ vm_page_t m;
+
+ mtx_assert(&vm_page_queue_mtx, MA_OWNED);
+ KASSERT((pa & PDRMASK) == 0,
+ ("pmap_pv_promote_pde: pa is not 2mpage aligned"));
+
+ /*
+ * Transfer the first page's pv entry for this mapping to the
+ * 2mpage's pv list. Aside from avoiding the cost of a call
+ * to get_pv_entry(), a transfer avoids the possibility that
+ * get_pv_entry() calls pmap_collect() and that pmap_collect()
+ * removes one of the mappings that is being promoted.
+ */
+ m = PHYS_TO_VM_PAGE(pa);
+ va = trunc_2mpage(va);
+ pv = pmap_pvh_remove(&m->md, pmap, va);
+ KASSERT(pv != NULL, ("pmap_pv_promote_pde: pv not found"));
+ pvh = pa_to_pvh(pa);
+ TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_list);
+ /* Free the remaining NPTEPG - 1 pv entries. */
+ va_last = va + NBPDR - PAGE_SIZE;
+ do {
+ m++;
+ va += PAGE_SIZE;
+ pmap_pvh_free(&m->md, pmap, va);
+ } while (va < va_last);
+}
+
+/*
+ * First find and then destroy the pv entry for the specified pmap and virtual
+ * address. This operation can be performed on pv lists for either 4KB or 2MB
+ * page mappings.
+ */
+static void
+pmap_pvh_free(struct md_page *pvh, pmap_t pmap, vm_offset_t va)
+{
+ pv_entry_t pv;
+
+ pv = pmap_pvh_remove(pvh, pmap, va);
+ KASSERT(pv != NULL, ("pmap_pvh_free: pv not found"));
free_pv_entry(pmap, pv);
}
+static void
+pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va)
+{
+ struct md_page *pvh;
+
+ mtx_assert(&vm_page_queue_mtx, MA_OWNED);
+ pmap_pvh_free(&m->md, pmap, va);
+ if (TAILQ_EMPTY(&m->md.pv_list)) {
+ pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
+ if (TAILQ_EMPTY(&pvh->pv_list))
+ vm_page_flag_clear(m, PG_WRITEABLE);
+ }
+}
+
/*
* Create a pv entry for page at pa for
* (pmap, va).
@@ -1878,6 +2170,170 @@ pmap_try_insert_pv_entry(pmap_t pmap, vm
}
/*
+ * Create the pv entry for a 2MB page mapping.
+ */
+static boolean_t
+pmap_pv_insert_pde(pmap_t pmap, vm_offset_t va, vm_paddr_t pa)
+{
+ struct md_page *pvh;
+ pv_entry_t pv;
+
+ mtx_assert(&vm_page_queue_mtx, MA_OWNED);
+ if (pv_entry_count < pv_entry_high_water &&
+ (pv = get_pv_entry(pmap, TRUE)) != NULL) {
+ pv->pv_va = va;
+ pvh = pa_to_pvh(pa);
+ TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_list);
+ return (TRUE);
+ } else
+ return (FALSE);
+}
+
+/*
+ * Tries to demote a 2MB page mapping.
+ */
+static boolean_t
+pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
+{
+ pd_entry_t newpde, oldpde;
+ pt_entry_t *firstpte, newpte, *pte;
+ vm_paddr_t mptepa;
+ vm_page_t free, mpte;
+
+ PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+ mpte = pmap_lookup_pt_page(pmap, va);
+ if (mpte != NULL)
+ pmap_remove_pt_page(pmap, mpte);
+ else {
+ KASSERT((*pde & PG_W) == 0,
+ ("pmap_demote_pde: page table page for a wired mapping"
+ " is missing"));
+ free = NULL;
+ pmap_remove_pde(pmap, pde, trunc_2mpage(va), &free);
+ pmap_invalidate_page(pmap, trunc_2mpage(va));
+ pmap_free_zero_pages(free);
+ CTR2(KTR_PMAP, "pmap_demote_pde: failure for va %#lx"
+ " in pmap %p", va, pmap);
+ return (FALSE);
+ }
+ mptepa = VM_PAGE_TO_PHYS(mpte);
+ firstpte = (pt_entry_t *)PHYS_TO_DMAP(mptepa);
+ oldpde = *pde;
+ newpde = mptepa | PG_M | PG_A | (oldpde & PG_U) | PG_RW | PG_V;
+ KASSERT((oldpde & (PG_A | PG_V)) == (PG_A | PG_V),
+ ("pmap_demote_pde: oldpde is missing PG_A and/or PG_V"));
+ KASSERT((oldpde & (PG_M | PG_RW)) != PG_RW,
+ ("pmap_demote_pde: oldpde is missing PG_M"));
+ KASSERT((oldpde & PG_PS) != 0,
+ ("pmap_demote_pde: oldpde is missing PG_PS"));
+ newpte = oldpde & ~PG_PS;
+ if ((newpte & PG_PDE_PAT) != 0)
+ newpte ^= PG_PDE_PAT | PG_PTE_PAT;
+
+ /*
+ * If the mapping has changed attributes, update the page table
+ * entries.
+ */
+ KASSERT((*firstpte & PG_FRAME) == (newpte & PG_FRAME),
+ ("pmap_demote_pde: firstpte and newpte map different physical"
+ " addresses"));
+ if ((*firstpte & PG_PTE_PROMOTE) != (newpte & PG_PTE_PROMOTE))
+ for (pte = firstpte; pte < firstpte + NPTEPG; pte++) {
+ *pte = newpte;
+ newpte += PAGE_SIZE;
+ }
+
+ /*
+ * Demote the mapping. This pmap is locked. The old PDE has
+ * PG_A set. If the old PDE has PG_RW set, it also has PG_M
+ * set. Thus, there is no danger of a race with another
+ * processor changing the setting of PG_A and/or PG_M between
+ * the read above and the store below.
+ */
+ pde_store(pde, newpde);
+
+ /*
+ * Invalidate a stale mapping of the page table page.
+ */
+ pmap_invalidate_page(pmap, (vm_offset_t)vtopte(va));
+
+ /*
+ * Demote the pv entry. This depends on the earlier demotion
+ * of the mapping. Specifically, the (re)creation of a per-
+ * page pv entry might trigger the execution of pmap_collect(),
+ * which might reclaim a newly (re)created per-page pv entry
+ * and destroy the associated mapping. In order to destroy
+ * the mapping, the PDE must have already changed from mapping
+ * the 2mpage to referencing the page table page.
+ */
+ if ((oldpde & PG_MANAGED) != 0)
+ pmap_pv_demote_pde(pmap, va, oldpde & PG_PS_FRAME);
+
+ pmap_pde_demotions++;
+ CTR2(KTR_PMAP, "pmap_demote_pde: success for va %#lx"
+ " in pmap %p", va, pmap);
+ return (TRUE);
+}
+
+/*
+ * pmap_remove_pde: do the things to unmap a superpage in a process
+ */
+static int
+pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
+ vm_page_t *free)
+{
+ struct md_page *pvh;
+ pd_entry_t oldpde;
+ vm_offset_t eva, va;
+ vm_page_t m, mpte;
+
+ PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+ KASSERT((sva & PDRMASK) == 0,
+ ("pmap_remove_pde: sva is not 2mpage aligned"));
+ oldpde = pte_load_clear(pdq);
+ if (oldpde & PG_W)
+ pmap->pm_stats.wired_count -= NBPDR / PAGE_SIZE;
+
+ /*
+ * Machines that don't support invlpg, also don't support
+ * PG_G.
+ */
+ if (oldpde & PG_G)
+ pmap_invalidate_page(kernel_pmap, sva);
+ pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
+ if (oldpde & PG_MANAGED) {
+ pvh = pa_to_pvh(oldpde & PG_PS_FRAME);
+ pmap_pvh_free(pvh, pmap, sva);
+ eva = sva + NBPDR;
+ for (va = sva, m = PHYS_TO_VM_PAGE(oldpde & PG_PS_FRAME);
+ va < eva; va += PAGE_SIZE, m++) {
+ if ((oldpde & (PG_M | PG_RW)) == (PG_M | PG_RW))
+ vm_page_dirty(m);
+ if (oldpde & PG_A)
+ vm_page_flag_set(m, PG_REFERENCED);
+ if (TAILQ_EMPTY(&m->md.pv_list) &&
+ TAILQ_EMPTY(&pvh->pv_list))
+ vm_page_flag_clear(m, PG_WRITEABLE);
+ }
+ }
+ if (pmap == kernel_pmap) {
+ if (!pmap_demote_pde(pmap, pdq, sva))
+ panic("pmap_remove_pde: failed demotion");
+ } else {
+ mpte = pmap_lookup_pt_page(pmap, sva);
+ if (mpte != NULL) {
+ pmap_remove_pt_page(pmap, mpte);
+ KASSERT(mpte->wire_count == NPTEPG,
+ ("pmap_remove_pde: pte page wire count error"));
+ mpte->wire_count = 0;
+ pmap_add_delayed_free_list(mpte, free, FALSE);
+ atomic_subtract_int(&cnt.v_wire_count, 1);
+ }
+ }
+ return (pmap_unuse_pt(pmap, sva, *pmap_pdpe(pmap, sva), free));
+}
+
+/*
* pmap_remove_pte: do the things to unmap a page in a process
*/
static int
@@ -1900,12 +2356,8 @@ pmap_remove_pte(pmap_t pmap, pt_entry_t
pmap->pm_stats.resident_count -= 1;
if (oldpte & PG_MANAGED) {
m = PHYS_TO_VM_PAGE(oldpte & PG_FRAME);
- if (oldpte & PG_M) {
- KASSERT((oldpte & PG_RW),
- ("pmap_remove_pte: modified page not writable: va: %#lx, pte: %#lx",
- va, oldpte));
+ if ((oldpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
- }
if (oldpte & PG_A)
vm_page_flag_set(m, PG_REFERENCED);
pmap_remove_entry(pmap, m, va);
@@ -2013,11 +2465,24 @@ pmap_remove(pmap_t pmap, vm_offset_t sva
* Check for large page.
*/
if ((ptpaddr & PG_PS) != 0) {
- *pde = 0;
- pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
- pmap_unuse_pt(pmap, sva, *pdpe, &free);
- anyvalid = 1;
- continue;
+ /*
+ * Are we removing the entire large page? If not,
+ * demote the mapping and fall through.
+ */
+ if (sva + NBPDR == va_next && eva >= va_next) {
+ /*
+ * The TLB entry for a PG_G mapping is
+ * invalidated by pmap_remove_pde().
+ */
+ if ((ptpaddr & PG_G) == 0)
+ anyvalid = 1;
+ pmap_remove_pde(pmap, pde, sva, &free);
+ continue;
+ } else if (!pmap_demote_pde(pmap, pde, sva)) {
+ /* The large page mapping was destroyed. */
+ continue;
+ } else
+ ptpaddr = *pde;
}
/*
@@ -2067,30 +2532,34 @@ out:
void
pmap_remove_all(vm_page_t m)
{
+ struct md_page *pvh;
pv_entry_t pv;
pmap_t pmap;
pt_entry_t *pte, tpte;
- pd_entry_t ptepde;
+ pd_entry_t *pde;
+ vm_offset_t va;
vm_page_t free;
-#if defined(PMAP_DIAGNOSTIC)
- /*
- * XXX This makes pmap_remove_all() illegal for non-managed pages!
- */
- if (m->flags & PG_FICTITIOUS) {
- panic("pmap_remove_all: illegal for unmanaged page, va: 0x%lx",
- VM_PAGE_TO_PHYS(m));
- }
-#endif
+ KASSERT((m->flags & PG_FICTITIOUS) == 0,
+ ("pmap_remove_all: page %p is fictitious", m));
mtx_assert(&vm_page_queue_mtx, MA_OWNED);
+ pvh = pa_to_pvh(VM_PAGE_TO_PHYS(m));
+ while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
+ va = pv->pv_va;
+ pmap = PV_PMAP(pv);
+ PMAP_LOCK(pmap);
+ pde = pmap_pde(pmap, va);
+ (void)pmap_demote_pde(pmap, pde, va);
+ PMAP_UNLOCK(pmap);
+ }
while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
pmap = PV_PMAP(pv);
PMAP_LOCK(pmap);
pmap->pm_stats.resident_count--;
- pte = pmap_pte_pde(pmap, pv->pv_va, &ptepde);
- if (pte == NULL) {
- panic("null pte in pmap_remove_all");
- }
+ pde = pmap_pde(pmap, pv->pv_va);
+ KASSERT((*pde & PG_PS) == 0, ("pmap_remove_all: found"
+ " a 2mpage in page %p's pv list", m));
+ pte = pmap_pde_to_pte(pde, pv->pv_va);
tpte = pte_load_clear(pte);
if (tpte & PG_W)
pmap->pm_stats.wired_count--;
@@ -2100,14 +2569,10 @@ pmap_remove_all(vm_page_t m)
/*
* Update the vm_page_t clean and reference bits.
*/
- if (tpte & PG_M) {
- KASSERT((tpte & PG_RW),
- ("pmap_remove_all: modified page not writable: va: %#lx, pte: %#lx",
- pv->pv_va, tpte));
+ if ((tpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
- }
free = NULL;
- pmap_unuse_pt(pmap, pv->pv_va, ptepde, &free);
+ pmap_unuse_pt(pmap, pv->pv_va, *pde, &free);
pmap_invalidate_page(pmap, pv->pv_va);
pmap_free_zero_pages(free);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
@@ -2118,6 +2583,54 @@ pmap_remove_all(vm_page_t m)
}
/*
+ * pmap_protect_pde: do the things to protect a 2mpage in a process
+ */
+static boolean_t
+pmap_protect_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t sva, vm_prot_t prot)
*** DIFF OUTPUT TRUNCATED AT 1000 LINES ***
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