mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-18 10:35:55 +00:00
Eliminate pmap_install(), which was used to wrap pmap_switch() and
grab sched_lock. This would serialize calls to pmap_switch from cpu_switch(). With the introduction of thread_lock, this is not possible anymore, because thread_lock is not a single lock. It varies. Secondly and most importantly, it's not needed at all. The only requirement for pmap_switch() is that it's not preempted while in the middle of updating the CPU and PCPU. In other words, it's a critical region. No locking required.
This commit is contained in:
Marcel Moolenaar
parent
5cca41595d
commit
f545763cbd
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=170402
@ -240,7 +240,6 @@ static pv_entry_t get_pv_entry(pmap_t locked_pmap);
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static void pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va,
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vm_page_t m, vm_prot_t prot);
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static pmap_t pmap_install(pmap_t);
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static void pmap_invalidate_all(pmap_t pmap);
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static int pmap_remove_pte(pmap_t pmap, struct ia64_lpte *pte,
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vm_offset_t va, pv_entry_t pv, int freepte);
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@ -565,9 +564,9 @@ pmap_invalidate_page_1(void *arg)
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pmap_t oldpmap;
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critical_enter();
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oldpmap = pmap_install(args[0]);
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oldpmap = pmap_switch(args[0]);
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pmap_invalidate_page_locally(args[1]);
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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critical_exit();
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}
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#endif
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@ -844,11 +843,11 @@ get_pv_entry(pmap_t locked_pmap)
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PMAP_LOCK(pmap);
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else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap))
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continue;
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pte = pmap_find_vhpt(va);
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KASSERT(pte != NULL, ("pte"));
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pmap_remove_pte(pmap, pte, va, pv, 1);
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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if (pmap != locked_pmap)
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PMAP_UNLOCK(pmap);
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if (allocated_pv == NULL)
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@ -1053,11 +1052,11 @@ pmap_extract(pmap_t pmap, vm_offset_t va)
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pa = 0;
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pte = pmap_find_vhpt(va);
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if (pte != NULL && pmap_present(pte))
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pa = pmap_ppn(pte);
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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return (pa);
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}
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@ -1079,7 +1078,7 @@ pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
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m = NULL;
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vm_page_lock_queues();
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pte = pmap_find_vhpt(va);
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if (pte != NULL && pmap_present(pte) &&
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(pmap_prot(pte) & prot) == prot) {
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@ -1087,7 +1086,7 @@ pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
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vm_page_hold(m);
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}
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vm_page_unlock_queues();
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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return (m);
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}
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@ -1399,7 +1398,7 @@ pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
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vm_page_lock_queues();
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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/*
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* special handling of removing one page. a very
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@ -1430,7 +1429,7 @@ pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
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out:
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vm_page_unlock_queues();
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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@ -1469,13 +1468,13 @@ pmap_remove_all(vm_page_t m)
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vm_offset_t va = pv->pv_va;
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pte = pmap_find_vhpt(va);
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KASSERT(pte != NULL, ("pte"));
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if (pmap_ppn(pte) != VM_PAGE_TO_PHYS(m))
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panic("pmap_remove_all: pv_table for %lx is inconsistent", VM_PAGE_TO_PHYS(m));
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pmap_remove_pte(pmap, pte, va, pv, 1);
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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vm_page_flag_clear(m, PG_WRITEABLE);
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@ -1505,7 +1504,7 @@ pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
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vm_page_lock_queues();
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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while (sva < eva) {
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/*
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* If page is invalid, skip this page
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@ -1536,7 +1535,7 @@ pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
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sva += PAGE_SIZE;
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}
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vm_page_unlock_queues();
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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@ -1565,7 +1564,7 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
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vm_page_lock_queues();
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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va &= ~PAGE_MASK;
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#ifdef DIAGNOSTIC
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@ -1577,13 +1576,13 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
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* Find (or create) a pte for the given mapping.
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*/
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while ((pte = pmap_find_pte(va)) == NULL) {
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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vm_page_unlock_queues();
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VM_WAIT;
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vm_page_lock_queues();
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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}
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origpte = *pte;
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if (!pmap_present(pte)) {
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@ -1660,7 +1659,7 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
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if ((prot & VM_PROT_WRITE) != 0)
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vm_page_flag_set(m, PG_WRITEABLE);
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vm_page_unlock_queues();
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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@ -1688,12 +1687,12 @@ pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
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psize = atop(end - start);
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m = m_start;
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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while (m != NULL && (diff = m->pindex - m_start->pindex) < psize) {
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pmap_enter_quick_locked(pmap, start + ptoa(diff), m, prot);
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m = TAILQ_NEXT(m, listq);
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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@ -1712,9 +1711,9 @@ pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
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pmap_t oldpmap;
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pmap_enter_quick_locked(pmap, va, m, prot);
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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@ -1789,7 +1788,7 @@ pmap_change_wiring(pmap, va, wired)
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struct ia64_lpte *pte;
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pte = pmap_find_vhpt(va);
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KASSERT(pte != NULL, ("pte"));
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@ -1801,7 +1800,7 @@ pmap_change_wiring(pmap, va, wired)
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pmap_clear_wired(pte);
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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@ -1932,7 +1931,7 @@ pmap_remove_pages(pmap_t pmap)
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vm_page_lock_queues();
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) {
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struct ia64_lpte *pte;
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@ -1945,7 +1944,7 @@ pmap_remove_pages(pmap_t pmap)
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pmap_remove_pte(pmap, pte, pv->pv_va, pv, 1);
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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vm_page_unlock_queues();
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}
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@ -1975,7 +1974,7 @@ pmap_ts_referenced(vm_page_t m)
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TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
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PMAP_LOCK(pv->pv_pmap);
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oldpmap = pmap_install(pv->pv_pmap);
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oldpmap = pmap_switch(pv->pv_pmap);
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pte = pmap_find_vhpt(pv->pv_va);
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KASSERT(pte != NULL, ("pte"));
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if (pmap_accessed(pte)) {
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@ -1983,7 +1982,7 @@ pmap_ts_referenced(vm_page_t m)
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pmap_clear_accessed(pte);
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pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pv->pv_pmap);
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}
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@ -2010,9 +2009,9 @@ pmap_is_modified(vm_page_t m)
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TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
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PMAP_LOCK(pv->pv_pmap);
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oldpmap = pmap_install(pv->pv_pmap);
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oldpmap = pmap_switch(pv->pv_pmap);
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pte = pmap_find_vhpt(pv->pv_va);
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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KASSERT(pte != NULL, ("pte"));
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rv = pmap_dirty(pte) ? TRUE : FALSE;
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PMAP_UNLOCK(pv->pv_pmap);
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@ -2055,14 +2054,14 @@ pmap_clear_modify(vm_page_t m)
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TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
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PMAP_LOCK(pv->pv_pmap);
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oldpmap = pmap_install(pv->pv_pmap);
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oldpmap = pmap_switch(pv->pv_pmap);
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pte = pmap_find_vhpt(pv->pv_va);
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KASSERT(pte != NULL, ("pte"));
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if (pmap_dirty(pte)) {
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pmap_clear_dirty(pte);
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pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pv->pv_pmap);
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}
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}
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@ -2084,14 +2083,14 @@ pmap_clear_reference(vm_page_t m)
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TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
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PMAP_LOCK(pv->pv_pmap);
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oldpmap = pmap_install(pv->pv_pmap);
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oldpmap = pmap_switch(pv->pv_pmap);
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pte = pmap_find_vhpt(pv->pv_va);
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KASSERT(pte != NULL, ("pte"));
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if (pmap_accessed(pte)) {
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pmap_clear_accessed(pte);
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pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pv->pv_pmap);
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}
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}
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@ -2114,7 +2113,7 @@ pmap_remove_write(vm_page_t m)
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TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
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pmap = pv->pv_pmap;
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pte = pmap_find_vhpt(pv->pv_va);
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KASSERT(pte != NULL, ("pte"));
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prot = pmap_prot(pte);
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@ -2127,7 +2126,7 @@ pmap_remove_write(vm_page_t m)
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pmap_pte_prot(pmap, pte, prot);
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pmap_invalidate_page(pmap, pv->pv_va);
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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}
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vm_page_flag_clear(m, PG_WRITEABLE);
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@ -2165,13 +2164,13 @@ pmap_mincore(pmap_t pmap, vm_offset_t addr)
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int val = 0;
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PMAP_LOCK(pmap);
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oldpmap = pmap_install(pmap);
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oldpmap = pmap_switch(pmap);
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pte = pmap_find_vhpt(addr);
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if (pte != NULL) {
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tpte = *pte;
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pte = &tpte;
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}
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pmap_install(oldpmap);
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pmap_switch(oldpmap);
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PMAP_UNLOCK(pmap);
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if (pte == NULL)
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@ -2226,7 +2225,7 @@ pmap_mincore(pmap_t pmap, vm_offset_t addr)
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void
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pmap_activate(struct thread *td)
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{
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pmap_install(vmspace_pmap(td->td_proc->p_vmspace));
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pmap_switch(vmspace_pmap(td->td_proc->p_vmspace));
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}
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pmap_t
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@ -2235,10 +2234,10 @@ pmap_switch(pmap_t pm)
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pmap_t prevpm;
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int i;
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THREAD_LOCK_ASSERT(curthread, MA_OWNED);
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critical_enter();
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prevpm = PCPU_GET(current_pmap);
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if (prevpm == pm)
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return (prevpm);
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goto out;
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if (prevpm != NULL)
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atomic_clear_32(&prevpm->pm_active, PCPU_GET(cpumask));
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if (pm == NULL) {
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@ -2255,20 +2254,9 @@ pmap_switch(pmap_t pm)
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}
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PCPU_SET(current_pmap, pm);
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__asm __volatile("srlz.d");
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return (prevpm);
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}
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static pmap_t
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pmap_install(pmap_t pm)
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{
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pmap_t prevpm;
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struct thread *td;
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td = curthread;
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thread_lock(td);
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prevpm = pmap_switch(pm);
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thread_unlock(td);
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out:
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critical_exit();
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return (prevpm);
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}
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