[src/trunk]: src/sys/arch/usermode/usermode Implement a new TLB system. This ...

[reinoud <reinoud%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/1cda000666d2
branches:  trunk
changeset: 772007:1cda000666d2
user:      reinoud <reinoud%NetBSD.org@localhost>
date:      Tue Dec 13 12:29:19 2011 +0000

description:
Implement a new TLB system. This fixes the TLB issues that has been plaguing
the pmap.

diffstat:

 sys/arch/usermode/usermode/pmap.c |  50 +++++++++++++++++++++++++++++---------
 1 files changed, 38 insertions(+), 12 deletions(-)

diffs (121 lines):

diff -r b871ee55fc3e -r 1cda000666d2 sys/arch/usermode/usermode/pmap.c
--- a/sys/arch/usermode/usermode/pmap.c Tue Dec 13 12:27:06 2011 +0000
+++ b/sys/arch/usermode/usermode/pmap.c Tue Dec 13 12:29:19 2011 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.75 2011/12/13 11:11:03 reinoud Exp $ */
+/* $NetBSD: pmap.c,v 1.76 2011/12/13 12:29:19 reinoud Exp $ */
 
 /*-
  * Copyright (c) 2011 Reinoud Zandijk <reinoud%NetBSD.org@localhost>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.75 2011/12/13 11:11:03 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.76 2011/12/13 12:29:19 reinoud Exp $");
 
 #include "opt_memsize.h"
 #include "opt_kmempages.h"
@@ -52,7 +52,6 @@
        uint8_t         pv_vflags;      /* per mapping flags */
 #define PV_WIRED       0x01            /* wired mapping */
 #define PV_UNMANAGED   0x02            /* entered by pmap_kenter_ */
-#define PV_MAPPEDIN    0x04            /* is actually mapped */
        uint8_t         pv_pflags;      /* per phys page flags */
 #define PV_REFERENCED  0x01
 #define PV_MODIFIED    0x02
@@ -66,9 +65,10 @@
        struct  pv_entry **pm_entries;
 };
 
-static struct pv_entry *pv_table;
-static struct pmap     pmap_kernel_store;
-struct pmap * const    kernel_pmap_ptr = &pmap_kernel_store;
+static struct pv_entry  *pv_table;     /* physical pages */
+static struct pv_entry **tlb;          /* current tlb mappings */
+static struct pmap      pmap_kernel_store;
+struct pmap * const     kernel_pmap_ptr = &pmap_kernel_store;
 
 static pmap_t active_pmap = NULL;
 
@@ -117,7 +117,7 @@
        struct pmap *pmap;
        paddr_t totmem_len;
        paddr_t fpos, file_len;
-       paddr_t pv_fpos, pm_fpos;
+       paddr_t pv_fpos, pm_fpos, tlb_fpos;
        paddr_t wlen;
        paddr_t user_len, barrier_len;
        paddr_t pv_table_size;
@@ -307,6 +307,25 @@
        kmem_ext_cur_start += pm_entries_size;
        fpos += pm_entries_size;
 
+       /* set up tlb space */
+       tlb = (struct pv_entry **) kmem_ext_cur_start;
+
+       tlb_fpos = fpos;
+       addr = thunk_mmap(tlb, pm_entries_size,
+               THUNK_PROT_READ | THUNK_PROT_WRITE,
+               THUNK_MAP_FILE | THUNK_MAP_FIXED | THUNK_MAP_SHARED,
+               mem_fh, tlb_fpos);
+       if (addr != (void *) tlb)
+               panic("pmap_bootstrap: can't map in tlb entries\n");
+
+       memset(tlb, 0, pm_entries_size);        /* test and clear */
+
+       dprintf_debug("kernel tlb entries initialiased correctly\n");
+
+       /* advance */
+       kmem_ext_cur_start += pm_entries_size;
+       fpos += pm_entries_size;
+
        /* kmem used [kmem_ext_start - kmem_ext_cur_start] */
        kmem_ext_cur_end = kmem_ext_cur_start;
 
@@ -323,6 +342,12 @@
                pmap_kenter_pa(va, pa, VM_PROT_READ | VM_PROT_WRITE, 0);
        }
        dprintf_debug("kernel pmap entries mem added to the kernel pmap\n");
+       for (pg = 0; pg < pm_entries_size; pg += PAGE_SIZE) {
+               pa = tlb_fpos + pg;
+               va = (vaddr_t) tlb + pg;
+               pmap_kenter_pa(va, pa, VM_PROT_READ | VM_PROT_WRITE, 0);
+       }
+       dprintf_debug("kernel tlb entries mem added to the kernel pmap\n");
 
        /* add file space to uvm's FREELIST */
        /* XXX really from 0? or from fpos to have better stats */
@@ -519,8 +544,8 @@
                return true;
        }
 
-       /* if its not mapped in, we have a TLB fault */
-       if ((pv->pv_vflags & PV_MAPPEDIN) == 0) {
+       /* check the TLB, if NULL we have a TLB fault */
+       if (tlb[pv->pv_lpn] == NULL) {
                if (pv->pv_mmap_ppl != THUNK_PROT_NONE) {
                        dprintf_debug("%s: tlb fault page lpn %"PRIiPTR"\n",
                                __func__, pv->pv_lpn);
@@ -606,9 +631,9 @@
                panic("pmap_page_activate: mmap failed (expected %p got %p): %d",
                    (void *)va, addr, thunk_geterrno());
 
-       pv->pv_vflags &= ~PV_MAPPEDIN;
+       tlb[pv->pv_lpn] = NULL;
        if (pv->pv_mmap_ppl != THUNK_PROT_NONE)
-               pv->pv_vflags |= PV_MAPPEDIN;
+               tlb[pv->pv_lpn] = pv;
 }
 
 static void
@@ -625,7 +650,8 @@
                (void *) va, (void *) pa, pv->pv_mmap_ppl, (void *) addr);
        if (addr != (void *) va)
                panic("pmap_page_deactivate: mmap failed");
-       pv->pv_vflags &= ~PV_MAPPEDIN;
+
+       tlb[pv->pv_lpn] = NULL;
 }
 
 static void