Apply MIPS pmap clean up patch from alc@ (with minor change to KASSERT):

  PMAP_DIAGNOSTIC was eliminated from amd64/i386, and, in fact, the
  non-MIPS parts of the kernel, several years ago.  Any of the interesting
  checks were turned into KASSERT()s.  Basically, the motivation was that
  lots of people run with INVARIANTS but no one runs with DIAGNOSTIC.

  panic strings needn't and shouldn't have a terminating newline.

  Finally, there is one functional change.  The sched_pin() in
  pmap_remove_pages() is an artifact of the way we temporarily map page
  table pages on i386.  (The mappings are processor private.  We don't do
  a system-wide shootdown.)  It isn't needed by MIPS.

Tested by: jchandra

Submitted by:	alc

2 files changed, 14 insertions, 67 deletions

diff --git a/sys/mips/include/pmap.h b/sys/mips/include/pmap.h
index 5432519..e6aada9 100644
--- a/sys/mips/include/pmap.h
+++ b/sys/mips/include/pmap.h
@@ -126,11 +126,6 @@ typedef struct pv_entry {
 	vm_page_t pv_ptem;	/* VM page for pte */
 }       *pv_entry_t;
 
-
-#if defined(DIAGNOSTIC)
-#define	PMAP_DIAGNOSTIC
-#endif
-
 /*
  * physmem_desc[] is a superset of phys_avail[] and describes all the
  * memory present in the system.
diff --git a/sys/mips/mips/pmap.c b/sys/mips/mips/pmap.c
index 2ff6f1c..89332d3 100644
--- a/sys/mips/mips/pmap.c
+++ b/sys/mips/mips/pmap.c
@@ -105,17 +105,13 @@ __FBSDID("$FreeBSD$");
 #include <machine/md_var.h>
 #include <machine/tlb.h>
 
-#if defined(DIAGNOSTIC)
-#define	PMAP_DIAGNOSTIC
-#endif
-
 #undef PMAP_DEBUG
 
 #ifndef PMAP_SHPGPERPROC
 #define	PMAP_SHPGPERPROC 200
 #endif
 
-#if !defined(PMAP_DIAGNOSTIC)
+#if !defined(DIAGNOSTIC)
 #define	PMAP_INLINE __inline
 #else
 #define	PMAP_INLINE
@@ -635,22 +631,6 @@ pmap_init(void)
  * Low level helper routines.....
  ***************************************************/
 
-#if defined(PMAP_DIAGNOSTIC)
-
-/*
- * This code checks for non-writeable/modified pages.
- * This should be an invalid condition.
- */
-static int
-pmap_nw_modified(pt_entry_t pte)
-{
-	if ((pte & (PTE_D | PTE_RO)) == (PTE_D | PTE_RO))
-		return (1);
-	else
-		return (0);
-}
-#endif
-
 static __inline void
 pmap_invalidate_all_local(pmap_t pmap)
 {
@@ -1598,13 +1578,9 @@ pmap_remove_pte(struct pmap *pmap, pt_entry_t *ptq, vm_offset_t va)
 	if (page_is_managed(pa)) {
 		m = PHYS_TO_VM_PAGE(pa);
 		if (pte_test(&oldpte, PTE_D)) {
-#if defined(PMAP_DIAGNOSTIC)
-			if (pmap_nw_modified(oldpte)) {
-				printf(
-				    "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n",
-				    va, oldpte);
-			}
-#endif
+			KASSERT(!pte_test(&oldpte, PTE_RO),
+			    ("%s: modified page not writable: va: %p, pte: 0x%x",
+			    __func__, (void *)va, oldpte));
 			vm_page_dirty(m);
 		}
 		if (m->md.pv_flags & PV_TABLE_REF)
@@ -1761,13 +1737,9 @@ pmap_remove_all(vm_page_t m)
 		 * Update the vm_page_t clean and reference bits.
 		 */
 		if (pte_test(&tpte, PTE_D)) {
-#if defined(PMAP_DIAGNOSTIC)
-			if (pmap_nw_modified(tpte)) {
-				printf(
-				    "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n",
-				    pv->pv_va, tpte);
-			}
-#endif
+			KASSERT(!pte_test(&tpte, PTE_RO),
+			    ("%s: modified page not writable: va: %p, pte: 0x%x",
+			    __func__, (void *)pv->pv_va, tpte));
 			vm_page_dirty(m);
 		}
 		pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
@@ -1908,7 +1880,7 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m,
 	 * Page Directory table entry not valid, we need a new PT page
 	 */
 	if (pte == NULL) {
-		panic("pmap_enter: invalid page directory, pdir=%p, va=%p\n",
+		panic("pmap_enter: invalid page directory, pdir=%p, va=%p",
 		    (void *)pmap->pm_segtab, (void *)va);
 	}
 	pa = VM_PAGE_TO_PHYS(m);
@@ -1931,13 +1903,9 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t access, vm_page_t m,
 		else if (!wired && pte_test(&origpte, PTE_W))
 			pmap->pm_stats.wired_count--;
 
-#if defined(PMAP_DIAGNOSTIC)
-		if (pmap_nw_modified(origpte)) {
-			printf(
-			    "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n",
-			    va, origpte);
-		}
-#endif
+		KASSERT(!pte_test(&origpte, PTE_D | PTE_RO),
+		    ("%s: modified page not writable: va: %p, pte: 0x%x",
+		    __func__, (void *)va, origpte));
 
 		/*
 		 * Remove extra pte reference
@@ -2529,13 +2497,11 @@ pmap_remove_pages(pmap_t pmap)
 	}
 	vm_page_lock_queues();
 	PMAP_LOCK(pmap);
-	sched_pin();
-	//XXX need to be TAILQ_FOREACH_SAFE ?
-	for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) {
+	for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv != NULL; pv = npv) {
 
 		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
 		if (!pte_test(pte, PTE_V))
-			panic("pmap_remove_pages: page on pm_pvlist has no pte\n");
+			panic("pmap_remove_pages: page on pm_pvlist has no pte");
 		tpte = *pte;
 
 /*
@@ -2570,7 +2536,6 @@ pmap_remove_pages(pmap_t pmap)
 		pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
 		free_pv_entry(pv);
 	}
-	sched_unpin();
 	pmap_invalidate_all(pmap);
 	PMAP_UNLOCK(pmap);
 	vm_page_unlock_queues();
@@ -2596,12 +2561,6 @@ pmap_testbit(vm_page_t m, int bit)
 
 	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
-#if defined(PMAP_DIAGNOSTIC)
-		if (!pv->pv_pmap) {
-			printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va);
-			continue;
-		}
-#endif
 		PMAP_LOCK(pv->pv_pmap);
 		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
 		rv = pte_test(pte, bit);
@@ -2630,13 +2589,6 @@ pmap_changebit(vm_page_t m, int bit, boolean_t setem)
 	 * setting RO do we need to clear the VAC?
 	 */
 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
-#if defined(PMAP_DIAGNOSTIC)
-		if (!pv->pv_pmap) {
-			printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va);
-			continue;
-		}
-#endif
-
 		PMAP_LOCK(pv->pv_pmap);
 		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
 		if (setem) {
@@ -2723,7 +2675,7 @@ pmap_remove_write(vm_page_t m)
 		npv = TAILQ_NEXT(pv, pv_plist);
 		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
 		if (pte == NULL || !pte_test(pte, PTE_V))
-			panic("page on pm_pvlist has no pte\n");
+			panic("page on pm_pvlist has no pte");
 
 		va = pv->pv_va;
 		pmap_protect(pv->pv_pmap, va, va + PAGE_SIZE,