Port the new PV entry allocator from amd64/i386. This allocator has two

advantages.  First, PV entries are roughly half the size.  Second, this
allocator doesn't access the paging queues, and thus it allows for the
removal of the page queues lock from this pmap.

Replace all uses of the page queues lock by a R/W lock that is private
to this pmap.

Tested by:	marcel

1 files changed, 17 insertions, 4 deletions

diff --git a/sys/ia64/include/pmap.h b/sys/ia64/include/pmap.h
index 3c4539f..fca4c78 100644
--- a/sys/ia64/include/pmap.h
+++ b/sys/ia64/include/pmap.h
@@ -64,16 +64,16 @@
  * Pmap stuff
  */
 struct	pv_entry;
+struct	pv_chunk;
 
 struct md_page {
-	int			pv_list_count;
 	TAILQ_HEAD(,pv_entry)	pv_list;
 	vm_memattr_t		memattr;
 };
 
 struct pmap {
 	struct mtx		pm_mtx;
-	TAILQ_HEAD(,pv_entry)	pm_pvlist;	/* list of mappings in pmap */
+	TAILQ_HEAD(,pv_chunk)	pm_pvchunk;	/* list of mappings in pmap */
 	uint32_t		pm_rid[IA64_VM_MINKERN_REGION];
 	struct pmap_statistics	pm_stats;	/* pmap statistics */
 };
@@ -101,12 +101,25 @@ extern struct pmap	kernel_pmap_store;
  * mappings of that page.  An entry is a pv_entry_t, the list is pv_list.
  */
 typedef struct pv_entry {
-	pmap_t		pv_pmap;	/* pmap where mapping lies */
 	vm_offset_t	pv_va;		/* virtual address for mapping */
 	TAILQ_ENTRY(pv_entry)	pv_list;
-	TAILQ_ENTRY(pv_entry)	pv_plist;
 } *pv_entry_t;
 
+/*
+ * pv_entries are allocated in chunks per-process.  This avoids the
+ * need to track per-pmap assignments.
+ */
+#define	_NPCM	6
+#define	_NPCPV	337
+struct pv_chunk {
+	pmap_t			pc_pmap;
+	TAILQ_ENTRY(pv_chunk)	pc_list;
+	u_long			pc_map[_NPCM];	/* bitmap; 1 = free */
+	TAILQ_ENTRY(pv_chunk)	pc_lru;
+	u_long			pc_spare[2];
+	struct pv_entry		pc_pventry[_NPCPV];
+};
+
 #ifdef	_KERNEL
 
 extern vm_paddr_t phys_avail[];