svn commit: r353541 - in head/sys: amd64/amd64 arm/arm arm64/arm64 i386/i386 mips/mips powerpc/aim powerpc/booke riscv/riscv sparc64/sparc64
Jeff Roberson
jeff at FreeBSD.org
Tue Oct 15 03:51:49 UTC 2019
Author: jeff
Date: Tue Oct 15 03:51:46 2019
New Revision: 353541
URL: https://svnweb.freebsd.org/changeset/base/353541
Log:
(6/6) Convert pmap to expect busy in write related operations now that all
callers hold it.
This simplifies pmap code and removes a dependency on the object lock.
Reviewed by: kib, markj
Tested by: pho
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D21596
Modified:
head/sys/amd64/amd64/pmap.c
head/sys/arm/arm/pmap-v4.c
head/sys/arm/arm/pmap-v6.c
head/sys/arm64/arm64/pmap.c
head/sys/i386/i386/pmap.c
head/sys/mips/mips/pmap.c
head/sys/powerpc/aim/mmu_oea.c
head/sys/powerpc/aim/mmu_oea64.c
head/sys/powerpc/booke/pmap.c
head/sys/riscv/riscv/pmap.c
head/sys/sparc64/sparc64/pmap.c
Modified: head/sys/amd64/amd64/pmap.c
==============================================================================
--- head/sys/amd64/amd64/pmap.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/amd64/amd64/pmap.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -7285,12 +7285,9 @@ pmap_is_modified(vm_page_t m)
("pmap_is_modified: page %p is not managed", m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can have PG_M set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
return (pmap_page_test_mappings(m, FALSE, TRUE));
}
@@ -7353,14 +7350,10 @@ pmap_remove_write(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ vm_page_assert_busied(m);
+ if (!pmap_page_is_write_mapped(m))
return;
+
lock = VM_PAGE_TO_PV_LIST_LOCK(m);
pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy :
pa_to_pvh(VM_PAGE_TO_PHYS(m));
@@ -7833,16 +7826,9 @@ pmap_clear_modify(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("pmap_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no PTEs can have PG_M set.
- * If the object containing the page is locked and the page is not
- * exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy :
pa_to_pvh(VM_PAGE_TO_PHYS(m));
Modified: head/sys/arm/arm/pmap-v4.c
==============================================================================
--- head/sys/arm/arm/pmap-v4.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/arm/arm/pmap-v4.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -4095,16 +4095,9 @@ pmap_clear_modify(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("pmap_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no mappings can be modified.
- * If the object containing the page is locked and the page is not
- * exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
if (m->md.pvh_attrs & PVF_MOD)
pmap_clearbit(m, PVF_MOD);
@@ -4136,14 +4129,9 @@ pmap_remove_write(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (vm_page_xbusied(m) || (m->aflags & PGA_WRITEABLE) != 0)
+ if (pmap_page_is_write_mapped(m))
pmap_clearbit(m, PVF_WRITE);
}
Modified: head/sys/arm/arm/pmap-v6.c
==============================================================================
--- head/sys/arm/arm/pmap-v6.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/arm/arm/pmap-v6.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -5192,12 +5192,9 @@ pmap_is_modified(vm_page_t m)
("%s: page %p is not managed", __func__, m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTE2s can have PG_M set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
rw_wlock(&pvh_global_lock);
rv = pmap_is_modified_pvh(&m->md) ||
@@ -5533,14 +5530,9 @@ pmap_remove_write(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("%s: page %p is not managed", __func__, m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
sched_pin();
@@ -5691,17 +5683,9 @@ pmap_clear_modify(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("%s: page %p is not managed", __func__, m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("%s: page %p is exclusive busy", __func__, m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no PTE2s can have PTE2_NM
- * cleared. If the object containing the page is locked and the page
- * is not exclusive busied, then PGA_WRITEABLE cannot be concurrently
- * set.
- */
- if ((m->flags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
sched_pin();
Modified: head/sys/arm64/arm64/pmap.c
==============================================================================
--- head/sys/arm64/arm64/pmap.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/arm64/arm64/pmap.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -4548,12 +4548,9 @@ pmap_is_modified(vm_page_t m)
("pmap_is_modified: page %p is not managed", m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can have PG_M set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
return (pmap_page_test_mappings(m, FALSE, TRUE));
}
@@ -4612,14 +4609,9 @@ pmap_remove_write(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
lock = VM_PAGE_TO_PV_LIST_LOCK(m);
pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy :
@@ -4987,16 +4979,9 @@ pmap_clear_modify(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("pmap_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no PTEs can have ATTR_SW_DBM
- * set. If the object containing the page is locked and the page is not
- * exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy :
pa_to_pvh(VM_PAGE_TO_PHYS(m));
Modified: head/sys/i386/i386/pmap.c
==============================================================================
--- head/sys/i386/i386/pmap.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/i386/i386/pmap.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -4874,12 +4874,9 @@ __CONCAT(PMTYPE, is_modified)(vm_page_t m)
("pmap_is_modified: page %p is not managed", m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can have PG_M set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
rw_wlock(&pvh_global_lock);
rv = pmap_is_modified_pvh(&m->md) ||
@@ -5003,14 +5000,9 @@ __CONCAT(PMTYPE, remove_write)(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
sched_pin();
@@ -5313,16 +5305,9 @@ __CONCAT(PMTYPE, clear_modify)(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("pmap_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no PTEs can have PG_M set.
- * If the object containing the page is locked and the page is not
- * exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
sched_pin();
Modified: head/sys/mips/mips/pmap.c
==============================================================================
--- head/sys/mips/mips/pmap.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/mips/mips/pmap.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -2893,14 +2893,9 @@ pmap_remove_write(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
@@ -2960,13 +2955,11 @@ pmap_is_modified(vm_page_t m)
("pmap_is_modified: page %p is not managed", m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can have PTE_D set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
+
rw_wlock(&pvh_global_lock);
rv = pmap_testbit(m, PTE_D);
rw_wunlock(&pvh_global_lock);
@@ -3101,15 +3094,9 @@ pmap_clear_modify(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("pmap_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no PTEs can have PTE_D set.
- * If the object containing the page is locked and the page is not
- * write busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
Modified: head/sys/powerpc/aim/mmu_oea.c
==============================================================================
--- head/sys/powerpc/aim/mmu_oea.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/powerpc/aim/mmu_oea.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -1314,13 +1314,11 @@ moea_is_modified(mmu_t mmu, vm_page_t m)
("moea_is_modified: page %p is not managed", m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can have PTE_CHG set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
+
rw_wlock(&pvh_global_lock);
rv = moea_query_bit(m, PTE_CHG);
rw_wunlock(&pvh_global_lock);
@@ -1346,16 +1344,9 @@ moea_clear_modify(mmu_t mmu, vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("moea_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("moea_clear_modify: page %p is exclusive busy", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no PTEs can have PTE_CHG
- * set. If the object containing the page is locked and the page is
- * not exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
moea_clear_bit(m, PTE_CHG);
@@ -1375,14 +1366,9 @@ moea_remove_write(mmu_t mmu, vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("moea_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
rw_wlock(&pvh_global_lock);
lo = moea_attr_fetch(m);
Modified: head/sys/powerpc/aim/mmu_oea64.c
==============================================================================
--- head/sys/powerpc/aim/mmu_oea64.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/powerpc/aim/mmu_oea64.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -1694,13 +1694,11 @@ moea64_is_modified(mmu_t mmu, vm_page_t m)
("moea64_is_modified: page %p is not managed", m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can have LPTE_CHG set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_LOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
+
return (moea64_query_bit(mmu, m, LPTE_CHG));
}
@@ -1724,16 +1722,9 @@ moea64_clear_modify(mmu_t mmu, vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("moea64_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("moea64_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no PTEs can have LPTE_CHG
- * set. If the object containing the page is locked and the page is
- * not exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
moea64_clear_bit(mmu, m, LPTE_CHG);
}
@@ -1750,15 +1741,11 @@ moea64_remove_write(mmu_t mmu, vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("moea64_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
- return;
+ if (!pmap_page_is_write_mapped(m))
+ return
+
powerpc_sync();
PV_PAGE_LOCK(m);
refchg = 0;
Modified: head/sys/powerpc/booke/pmap.c
==============================================================================
--- head/sys/powerpc/booke/pmap.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/powerpc/booke/pmap.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -2687,15 +2687,10 @@ mmu_booke_remove_write(mmu_t mmu, vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("mmu_booke_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
- return;
+ if (!pmap_page_is_write_mapped(m))
+ return;
rw_wlock(&pvh_global_lock);
TAILQ_FOREACH(pv, &m->md.pv_list, pv_link) {
PMAP_LOCK(pv->pv_pmap);
@@ -3035,13 +3030,11 @@ mmu_booke_is_modified(mmu_t mmu, vm_page_t m)
rv = FALSE;
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can be modified.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
- return (rv);
+ if (!pmap_page_is_write_mapped(m))
+ return (FALSE);
+
rw_wlock(&pvh_global_lock);
TAILQ_FOREACH(pv, &m->md.pv_list, pv_link) {
PMAP_LOCK(pv->pv_pmap);
@@ -3110,17 +3103,11 @@ mmu_booke_clear_modify(mmu_t mmu, vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("mmu_booke_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("mmu_booke_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PG_AWRITEABLE, then no PTEs can be modified.
- * If the object containing the page is locked and the page is not
- * exclusive busied, then PG_AWRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
- return;
+ if (!pmap_page_is_write_mapped(m))
+ return;
+
rw_wlock(&pvh_global_lock);
TAILQ_FOREACH(pv, &m->md.pv_list, pv_link) {
PMAP_LOCK(pv->pv_pmap);
Modified: head/sys/riscv/riscv/pmap.c
==============================================================================
--- head/sys/riscv/riscv/pmap.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/riscv/riscv/pmap.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -3814,12 +3814,9 @@ pmap_is_modified(vm_page_t m)
("pmap_is_modified: page %p is not managed", m));
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no PTEs can have PG_M set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (FALSE);
return (pmap_page_test_mappings(m, FALSE, TRUE));
}
@@ -3878,14 +3875,9 @@ pmap_remove_write(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
lock = VM_PAGE_TO_PV_LIST_LOCK(m);
pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy :
@@ -4136,9 +4128,10 @@ pmap_clear_modify(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("pmap_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
+
+ if (!pmap_page_is_write_mapped(m))
+ return;
/*
* If the page is not PGA_WRITEABLE, then no PTEs can have PG_M set.
Modified: head/sys/sparc64/sparc64/pmap.c
==============================================================================
--- head/sys/sparc64/sparc64/pmap.c Tue Oct 15 03:48:22 2019 (r353540)
+++ head/sys/sparc64/sparc64/pmap.c Tue Oct 15 03:51:46 2019 (r353541)
@@ -2116,12 +2116,9 @@ pmap_is_modified(vm_page_t m)
rv = FALSE;
/*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * concurrently set while the object is locked. Thus, if PGA_WRITEABLE
- * is clear, no TTEs can have TD_W set.
+ * If the page is not busied then this check is racy.
*/
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return (rv);
rw_wlock(&tte_list_global_lock);
TAILQ_FOREACH(tp, &m->md.tte_list, tte_link) {
@@ -2195,17 +2192,11 @@ pmap_clear_modify(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_clear_modify: page %p is not managed", m));
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- KASSERT(!vm_page_xbusied(m),
- ("pmap_clear_modify: page %p is exclusive busied", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not PGA_WRITEABLE, then no TTEs can have TD_W set.
- * If the object containing the page is locked and the page is not
- * exclusive busied, then PGA_WRITEABLE cannot be concurrently set.
- */
- if ((m->aflags & PGA_WRITEABLE) == 0)
+ if (!pmap_page_is_write_mapped(m))
return;
+
rw_wlock(&tte_list_global_lock);
TAILQ_FOREACH(tp, &m->md.tte_list, tte_link) {
if ((tp->tte_data & TD_PV) == 0)
@@ -2225,15 +2216,11 @@ pmap_remove_write(vm_page_t m)
KASSERT((m->oflags & VPO_UNMANAGED) == 0,
("pmap_remove_write: page %p is not managed", m));
+ vm_page_assert_busied(m);
- /*
- * If the page is not exclusive busied, then PGA_WRITEABLE cannot be
- * set by another thread while the object is locked. Thus,
- * if PGA_WRITEABLE is clear, no page table entries need updating.
- */
- VM_OBJECT_ASSERT_WLOCKED(m->object);
- if (!vm_page_xbusied(m) && (m->aflags & PGA_WRITEABLE) == 0)
- return;
+ if (!pmap_page_is_write_mapped(m))
+ return;
+
rw_wlock(&tte_list_global_lock);
TAILQ_FOREACH(tp, &m->md.tte_list, tte_link) {
if ((tp->tte_data & TD_PV) == 0)
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