Author: alc Date: Mon Jul 30 01:54:25 2018 New Revision: 336881 URL: https://svnweb.freebsd.org/changeset/base/336881
Log: Prepare for adding psind == 1 support to armv6's pmap_enter(). Precompute the new PTE before entering the critical section. Eliminate duplication of the pmap and pv list unlock operations in pmap_enter() by implementing a single return path. Otherwise, the duplication will only increase with the upcoming support for psind == 1. Reviewed by: mmel Tested by: mmel Discussed with: kib, markj MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D16443 Modified: head/sys/arm/arm/pmap-v6.c Modified: head/sys/arm/arm/pmap-v6.c ============================================================================== --- head/sys/arm/arm/pmap-v6.c Mon Jul 30 00:08:36 2018 (r336880) +++ head/sys/arm/arm/pmap-v6.c Mon Jul 30 01:54:25 2018 (r336881) @@ -3849,18 +3849,36 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, v pv_entry_t pv; vm_paddr_t opa, pa; vm_page_t mpte2, om; - boolean_t wired; + int rv; va = trunc_page(va); - mpte2 = NULL; - wired = (flags & PMAP_ENTER_WIRED) != 0; - KASSERT(va <= vm_max_kernel_address, ("%s: toobig", __func__)); KASSERT(va < UPT2V_MIN_ADDRESS || va >= UPT2V_MAX_ADDRESS, ("%s: invalid to pmap_enter page table pages (va: 0x%x)", __func__, va)); + KASSERT((m->oflags & VPO_UNMANAGED) != 0 || va < kmi.clean_sva || + va >= kmi.clean_eva, + ("%s: managed mapping within the clean submap", __func__)); if ((m->oflags & VPO_UNMANAGED) == 0 && !vm_page_xbusied(m)) VM_OBJECT_ASSERT_LOCKED(m->object); + KASSERT((flags & PMAP_ENTER_RESERVED) == 0, + ("%s: flags %u has reserved bits set", __func__, flags)); + pa = VM_PAGE_TO_PHYS(m); + npte2 = PTE2(pa, PTE2_A, vm_page_pte2_attr(m)); + if ((flags & VM_PROT_WRITE) == 0) + npte2 |= PTE2_NM; + if ((prot & VM_PROT_WRITE) == 0) + npte2 |= PTE2_RO; + KASSERT((npte2 & (PTE2_NM | PTE2_RO)) != PTE2_RO, + ("pmap_enter: flags includes VM_PROT_WRITE but prot doesn't")); + if ((prot & VM_PROT_EXECUTE) == 0) + npte2 |= PTE2_NX; + if ((flags & PMAP_ENTER_WIRED) != 0) + npte2 |= PTE2_W; + if (va < VM_MAXUSER_ADDRESS) + npte2 |= PTE2_U; + if (pmap != kernel_pmap) + npte2 |= PTE2_NG; rw_wlock(&pvh_global_lock); PMAP_LOCK(pmap); @@ -3875,12 +3893,11 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, v if (mpte2 == NULL) { KASSERT((flags & PMAP_ENTER_NOSLEEP) != 0, ("pmap_allocpte2 failed with sleep allowed")); - sched_unpin(); - rw_wunlock(&pvh_global_lock); - PMAP_UNLOCK(pmap); - return (KERN_RESOURCE_SHORTAGE); + rv = KERN_RESOURCE_SHORTAGE; + goto out; } - } + } else + mpte2 = NULL; pte1p = pmap_pte1(pmap, va); if (pte1_is_section(pte1_load(pte1p))) panic("%s: attempted on 1MB page", __func__); @@ -3889,7 +3906,6 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, v panic("%s: invalid L1 page table entry va=%#x", __func__, va); om = NULL; - pa = VM_PAGE_TO_PHYS(m); opte2 = pte2_load(pte2p); opa = pte2_pa(opte2); /* @@ -3902,9 +3918,9 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, v * are valid mappings in them. Hence, if a user page is wired, * the PT2 page will be also. */ - if (wired && !pte2_is_wired(opte2)) + if (pte2_is_wired(npte2) && !pte2_is_wired(opte2)) pmap->pm_stats.wired_count++; - else if (!wired && pte2_is_wired(opte2)) + else if (!pte2_is_wired(npte2) && pte2_is_wired(opte2)) pmap->pm_stats.wired_count--; /* @@ -3953,11 +3969,10 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, v * Enter on the PV list if part of our managed memory. */ if ((m->oflags & VPO_UNMANAGED) == 0) { - KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva, - ("%s: managed mapping within the clean submap", __func__)); - if (pv == NULL) + if (pv == NULL) { pv = get_pv_entry(pmap, FALSE); - pv->pv_va = va; + pv->pv_va = va; + } TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next); } else if (pv != NULL) free_pv_entry(pmap, pv); @@ -3965,28 +3980,17 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, v /* * Increment counters */ - if (wired) + if (pte2_is_wired(npte2)) pmap->pm_stats.wired_count++; validate: /* * Now validate mapping with desired protection/wiring. */ - npte2 = PTE2(pa, PTE2_NM, vm_page_pte2_attr(m)); if (prot & VM_PROT_WRITE) { if (pte2_is_managed(npte2)) vm_page_aflag_set(m, PGA_WRITEABLE); } - else - npte2 |= PTE2_RO; - if ((prot & VM_PROT_EXECUTE) == 0) - npte2 |= PTE2_NX; - if (wired) - npte2 |= PTE2_W; - if (va < VM_MAXUSER_ADDRESS) - npte2 |= PTE2_U; - if (pmap != kernel_pmap) - npte2 |= PTE2_NG; /* * If the mapping or permission bits are different, we need @@ -4016,9 +4020,6 @@ validate: (opa != pa || (opte2 & PTE2_NX))) cache_icache_sync_fresh(va, pa, PAGE_SIZE); - npte2 |= PTE2_A; - if (flags & VM_PROT_WRITE) - npte2 &= ~PTE2_NM; if (opte2 & PTE2_V) { /* Change mapping with break-before-make approach. */ opte2 = pte2_load_clear(pte2p); @@ -4063,10 +4064,13 @@ validate: vm_reserv_level_iffullpop(m) == 0) pmap_promote_pte1(pmap, pte1p, va); #endif + + rv = KERN_SUCCESS; +out: sched_unpin(); rw_wunlock(&pvh_global_lock); PMAP_UNLOCK(pmap); - return (KERN_SUCCESS); + return (rv); } /* _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
