Use superpages on restore/migrate

xen/arch/x86/mm/hap/p2m-ept.c +0 -2

@@ -167,11 +169,14 @@
 void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry, int level)
 {
     /* End if the entry is a leaf entry. */
-    if ( level == 0 || !is_epte_present(ept_entry) ||
-         is_epte_superpage(ept_entry) )

xen/arch/x86/mm/p2m.c +1 -1

@@ -184,11 +184,15 @@
 {
     /* End if the entry is a leaf entry. */
     if ( page_order == 0
-         || !(l1e_get_flags(*p2m_entry) & _PAGE_PRESENT)
+         || !(l1e_get_flags(*p2m_entry) & _PAGE_PRESENT) 

Count the number of 4kiB, 2MiB, and 1GiB p2m entries.

Signed-off-by George Dunlap<[email protected]>

diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/hap/p2m-ept.c

xen/arch/x86/mm/hap/p2m-ept.c Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c Thu May 05 17:40:34 2011 +0100 +24 -4

@@ -39,6 +39,8 @@
 
  #define is_epte_present(ept_entry)      ((ept_entry)->epte&  0x7)
  #define is_epte_superpage(ept_entry)    ((ept_entry)->sp)
+#define is_epte_countable(ept_entry)    (is_epte_present(ept_entry) \
+                                         || ((ept_entry)->sa_p2mt == p2m_populate_on_demand))
 
  /* Non-ept "lock-and-check" wrapper */
  static int ept_pod_check_and_populate(struct p2m_domain *p2m, unsigned long gfn,

@@ -167,11 +169,14 @@
  void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry, int level)
  {
      /* End if the entry is a leaf entry. */
-    if ( level == 0 || !is_epte_present(ept_entry) ||
-         is_epte_superpage(ept_entry) )
+    if ( level == 0 || !is_epte_present(ept_entry) || is_epte_superpage(ept_entry) )
+    {
+        if ( is_epte_countable(ept_entry) )
+            p2m->stats.entries[level]--;
          return;
+    }
 
-    if ( level>  1 )
+    if ( level>  0 )
      {
          ept_entry_t *epte = map_domain_page(ept_entry->mfn);
          for ( int i = 0; i<  EPT_PAGETABLE_ENTRIES; i++ )

@@ -217,7 +222,10 @@
          ept_p2m_type_to_flags(epte, epte->sa_p2mt, epte->access);
 
          if ( (level - 1) == target )
+        {
+            p2m->stats.entries[target]++;
              continue;
+        }
 
          ASSERT(is_epte_superpage(epte));
 

@@ -400,6 +408,10 @@
              ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
          }
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
          atomic_write_ept_entry(ept_entry, new_entry);
      }
      else

@@ -412,12 +424,16 @@
 
          split_ept_entry = atomic_read_ept_entry(ept_entry);
 
+        /* Accounting should be OK here; split_ept_entry bump the counts,
+         * free_entry will reduce them. */
          if ( !ept_split_super_page(p2m,&split_ept_entry, i, target) )
          {
              ept_free_entry(p2m,&split_ept_entry, i);
              goto out;
          }
 
+        /* We know this was countable or we wouldn't be here.*/
+        p2m->stats.entries[i]--;
          /* now install the newly split ept sub-tree */
          /* NB: please make sure domian is paused and no in-fly VT-d DMA. */
          atomic_write_ept_entry(ept_entry, split_ept_entry);

@@ -449,9 +465,13 @@
 
          ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
          atomic_write_ept_entry(ept_entry, new_entry);
      }
-
+
      /* Track the highest gfn for which we have ever had a valid mapping */
      if ( mfn_valid(mfn_x(mfn))&&
           (gfn + (1UL<<  order) - 1>  p2m->max_mapped_pfn) )

diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/p2m.c

xen/arch/x86/mm/p2m.c Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c Thu May 05 17:40:34 2011 +0100 +42 -3

@@ -184,11 +184,15 @@
  {
      /* End if the entry is a leaf entry. */
      if ( page_order == 0
-         || !(l1e_get_flags(*p2m_entry)&  _PAGE_PRESENT)
+         || !(l1e_get_flags(*p2m_entry)&  _PAGE_PRESENT)
           || (l1e_get_flags(*p2m_entry)&  _PAGE_PSE) )
+    {
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
          return;
-
-    if ( page_order>  9 )
+    }
+
+    if ( page_order )
      {
          l1_pgentry_t *l3_table = map_domain_page(l1e_get_pfn(*p2m_entry));
          for ( int i = 0; i<  L3_PAGETABLE_ENTRIES; i++ )

@@ -242,6 +246,7 @@
          new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                   __PAGE_HYPERVISOR | _PAGE_USER);
 
+        /* Stats: Empty entry, no mods needed */
          switch ( type ) {
          case PGT_l3_page_table:
              p2m_add_iommu_flags(&new_entry, 3, IOMMUF_readable|IOMMUF_writable);

@@ -285,10 +290,12 @@
          {
              new_entry = l1e_from_pfn(pfn + (i * L1_PAGETABLE_ENTRIES), flags);
              p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable);
+            p2m->stats.entries[1]++;
              p2m->write_p2m_entry(p2m, gfn,
                  l1_entry+i, *table_mfn, new_entry, 2);
          }
          unmap_domain_page(l1_entry);
+        p2m->stats.entries[2]--;
          new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                   __PAGE_HYPERVISOR|_PAGE_USER); //disable PSE
          p2m_add_iommu_flags(&new_entry, 2, IOMMUF_readable|IOMMUF_writable);

@@ -320,6 +327,7 @@
          {
              new_entry = l1e_from_pfn(pfn + i, flags);
              p2m_add_iommu_flags(&new_entry, 0, 0);
+            p2m->stats.entries[0]++;
              p2m->write_p2m_entry(p2m, gfn,
                  l1_entry+i, *table_mfn, new_entry, 1);
          }

@@ -328,6 +336,7 @@
          new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                   __PAGE_HYPERVISOR|_PAGE_USER);
          p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable);
+        p2m->stats.entries[1]--;
          p2m->write_p2m_entry(p2m, gfn,
              p2m_entry, *table_mfn, new_entry, 2);
      }

@@ -908,6 +917,15 @@
  void
  p2m_pod_dump_data(struct p2m_domain *p2m)
  {
+    int i;
+    long entries;
+    printk("    P2M entry stats:\n");
+    for ( i=0; i<3; i++)
+        if ( (entries=p2m->stats.entries[i]) )
+            printk("     L%d: %8ld entries, %ld bytes\n",
+                   i+1,
+                   entries,
+                   entries<<(i*9+12));
      printk("    PoD entries=%d cachesize=%d\n",
             p2m->pod.entry_count, p2m->pod.count);
  }

@@ -1475,6 +1493,12 @@
              old_mfn = l1e_get_pfn(*p2m_entry);
          }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
          p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 3);
          /* NB: paging_write_p2m_entry() handles tlb flushes properly */
 

@@ -1519,6 +1543,13 @@
              p2m_add_iommu_flags(&entry_content, 0, iommu_pte_flags);
              old_mfn = l1e_get_pfn(*p2m_entry);
          }
+
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
          /* level 1 entry */
          p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 1);
          /* NB: paging_write_p2m_entry() handles tlb flushes properly */

@@ -1556,6 +1587,12 @@
              old_mfn = l1e_get_pfn(*p2m_entry);
          }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
          p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 2);
          /* NB: paging_write_p2m_entry() handles tlb flushes properly */
 

@@ -2750,6 +2787,8 @@
                  continue;
              }
 
+            /* STATS: Should change only type; no stats should need adjustment */
+
              l2mfn = _mfn(l3e_get_pfn(l3e[i3]));
              l2e = map_domain_page(l3e_get_pfn(l3e[i3]));
              for ( i2 = 0; i2<  L2_PAGETABLE_ENTRIES; i2++ )

diff -r 4b0692880dfa -r be5d93d38f28 xen/include/asm-x86/p2m.h

xen/include/asm-x86/p2m.h Fri May 06 15:01:08 2011 +0100 renamed from xen/include/asm-x86/p2m.h Thu May 05 17:40:34 2011 +0100 +4 -0

@@ -278,6 +278,10 @@
          unsigned         reclaim_single; /* Last gpfn of a scan */
          unsigned         max_guest;    /* gpfn of max guest demand-populate */
      } pod;
+
+    struct {
+        long entries[3];
+    } stats;
  };
 
  /* get host p2m table */

_______________________________________________
Xen-devel mailing list
[email protected]
http://lists.xensource.com/xen-devel

Hello,

Quoted 2 lines · Christoph Egger

Can you please use defines for the indexes of p2m->stats.entries[], please? That makes it easier to read what you are counting.

I'm not sure that's a great idea. The array is indexed in several places by integer already, and the defines are unlikely to be much more illuminating unless you can think of some better naming scheme than "#define LEVEL_0 0" etc.

On the other hand, maybe the array itself could have a more descriptive name than "stats.entries".

Tim.

Quoted 227 lines · George Dunlap

Quoted 226 lines

Count the number of 4kiB, 2MiB, and 1GiB p2m entries.

Signed-off-by George Dunlap<[email protected]>

diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/hap/p2m-ept.c

xen/arch/x86/mm/hap/p2m-ept.c Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c Thu May 05 17:40:34 2011 +0100 +24 -4

@@ -39,6 +39,8 @@
 
   #define is_epte_present(ept_entry)      ((ept_entry)->epte&   0x7)
   #define is_epte_superpage(ept_entry)    ((ept_entry)->sp)
+#define is_epte_countable(ept_entry)    (is_epte_present(ept_entry) \
+                                         || ((ept_entry)->sa_p2mt == p2m_populate_on_demand))
 
   /* Non-ept "lock-and-check" wrapper */
   static int ept_pod_check_and_populate(struct p2m_domain *p2m, unsigned long gfn,

@@ -167,11 +169,14 @@
   void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry, int level)
   {
       /* End if the entry is a leaf entry. */
-    if ( level == 0 || !is_epte_present(ept_entry) ||
-         is_epte_superpage(ept_entry) )
+    if ( level == 0 || !is_epte_present(ept_entry) || is_epte_superpage(ept_entry) )
+    {
+        if ( is_epte_countable(ept_entry) )
+            p2m->stats.entries[level]--;
           return;
+    }
 
-    if ( level>   1 )
+    if ( level>   0 )
       {
           ept_entry_t *epte = map_domain_page(ept_entry->mfn);
           for ( int i = 0; i<   EPT_PAGETABLE_ENTRIES; i++ )

@@ -217,7 +222,10 @@
           ept_p2m_type_to_flags(epte, epte->sa_p2mt, epte->access);
 
           if ( (level - 1) == target )
+        {
+            p2m->stats.entries[target]++;
               continue;
+        }
 
           ASSERT(is_epte_superpage(epte));
 

@@ -400,6 +408,10 @@
               ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
           }
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
           atomic_write_ept_entry(ept_entry, new_entry);
       }
       else

@@ -412,12 +424,16 @@
 
           split_ept_entry = atomic_read_ept_entry(ept_entry);
 
+        /* Accounting should be OK here; split_ept_entry bump the counts,
+         * free_entry will reduce them. */
           if ( !ept_split_super_page(p2m,&split_ept_entry, i, target) )
           {
               ept_free_entry(p2m,&split_ept_entry, i);
               goto out;
           }
 
+        /* We know this was countable or we wouldn't be here.*/
+        p2m->stats.entries[i]--;
           /* now install the newly split ept sub-tree */
           /* NB: please make sure domian is paused and no in-fly VT-d DMA. */
           atomic_write_ept_entry(ept_entry, split_ept_entry);

@@ -449,9 +465,13 @@
 
           ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
           atomic_write_ept_entry(ept_entry, new_entry);
       }
-
+
       /* Track the highest gfn for which we have ever had a valid mapping */
       if ( mfn_valid(mfn_x(mfn))&&
            (gfn + (1UL<<   order) - 1>   p2m->max_mapped_pfn) )

diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/p2m.c

xen/arch/x86/mm/p2m.c Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c Thu May 05 17:40:34 2011 +0100 +42 -3

@@ -184,11 +184,15 @@
   {
       /* End if the entry is a leaf entry. */
       if ( page_order == 0
-         || !(l1e_get_flags(*p2m_entry)&   _PAGE_PRESENT)
+         || !(l1e_get_flags(*p2m_entry)&   _PAGE_PRESENT)
            || (l1e_get_flags(*p2m_entry)&   _PAGE_PSE) )
+    {
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
           return;
-
-    if ( page_order>   9 )
+    }
+
+    if ( page_order )
       {
           l1_pgentry_t *l3_table = map_domain_page(l1e_get_pfn(*p2m_entry));
           for ( int i = 0; i<   L3_PAGETABLE_ENTRIES; i++ )

@@ -242,6 +246,7 @@
           new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                    __PAGE_HYPERVISOR | _PAGE_USER);
 
+        /* Stats: Empty entry, no mods needed */
           switch ( type ) {
           case PGT_l3_page_table:
               p2m_add_iommu_flags(&new_entry, 3, IOMMUF_readable|IOMMUF_writable);

@@ -285,10 +290,12 @@
           {
               new_entry = l1e_from_pfn(pfn + (i * L1_PAGETABLE_ENTRIES), flags);
               p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable);
+            p2m->stats.entries[1]++;
               p2m->write_p2m_entry(p2m, gfn,
                   l1_entry+i, *table_mfn, new_entry, 2);
           }
           unmap_domain_page(l1_entry);
+        p2m->stats.entries[2]--;
           new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                    __PAGE_HYPERVISOR|_PAGE_USER); //disable PSE
           p2m_add_iommu_flags(&new_entry, 2, IOMMUF_readable|IOMMUF_writable);

@@ -320,6 +327,7 @@
           {
               new_entry = l1e_from_pfn(pfn + i, flags);
               p2m_add_iommu_flags(&new_entry, 0, 0);
+            p2m->stats.entries[0]++;
               p2m->write_p2m_entry(p2m, gfn,
                   l1_entry+i, *table_mfn, new_entry, 1);
           }

@@ -328,6 +336,7 @@
           new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                    __PAGE_HYPERVISOR|_PAGE_USER);
           p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable);
+        p2m->stats.entries[1]--;
           p2m->write_p2m_entry(p2m, gfn,
               p2m_entry, *table_mfn, new_entry, 2);
       }

@@ -908,6 +917,15 @@
   void
   p2m_pod_dump_data(struct p2m_domain *p2m)
   {
+    int i;
+    long entries;
+    printk("    P2M entry stats:\n");
+    for ( i=0; i<3; i++)
+        if ( (entries=p2m->stats.entries[i]) )
+            printk("     L%d: %8ld entries, %ld bytes\n",
+                   i+1,
+                   entries,
+                   entries<<(i*9+12));
       printk("    PoD entries=%d cachesize=%d\n",
              p2m->pod.entry_count, p2m->pod.count);
   }

@@ -1475,6 +1493,12 @@
               old_mfn = l1e_get_pfn(*p2m_entry);
           }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
           p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 3);
           /* NB: paging_write_p2m_entry() handles tlb flushes properly */
 

@@ -1519,6 +1543,13 @@
               p2m_add_iommu_flags(&entry_content, 0, iommu_pte_flags);
               old_mfn = l1e_get_pfn(*p2m_entry);
           }
+
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
           /* level 1 entry */
           p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 1);
           /* NB: paging_write_p2m_entry() handles tlb flushes properly */

@@ -1556,6 +1587,12 @@
               old_mfn = l1e_get_pfn(*p2m_entry);
           }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
           p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 2);
           /* NB: paging_write_p2m_entry() handles tlb flushes properly */
 

@@ -2750,6 +2787,8 @@
                   continue;
               }
 
+            /* STATS: Should change only type; no stats should need adjustment */
+
               l2mfn = _mfn(l3e_get_pfn(l3e[i3]));
               l2e = map_domain_page(l3e_get_pfn(l3e[i3]));
               for ( i2 = 0; i2<   L2_PAGETABLE_ENTRIES; i2++ )

diff -r 4b0692880dfa -r be5d93d38f28 xen/include/asm-x86/p2m.h

xen/include/asm-x86/p2m.h Fri May 06 15:01:08 2011 +0100 renamed from xen/include/asm-x86/p2m.h Thu May 05 17:40:34 2011 +0100 +4 -0

@@ -278,6 +278,10 @@
           unsigned         reclaim_single; /* Last gpfn of a scan */
           unsigned         max_guest;    /* gpfn of max guest demand-populate */
       } pod;
+
+    struct {
+        long entries[3];
+    } stats;
   };
 
   /* get host p2m table */

Can you please use defines for the indexes of p2m->stats.entries[], please? That makes it easier to read what you are counting.

Quoted 227 lines

Count the number of 4kiB, 2MiB, and 1GiB p2m entries.

Signed-off-by George Dunlap<[email protected]>

diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/hap/p2m-ept.c

xen/arch/x86/mm/hap/p2m-ept.c Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c Thu May 05 17:40:34 2011 +0100 +24 -4

@@ -39,6 +39,8 @@
 
  #define is_epte_present(ept_entry)      ((ept_entry)->epte&  0x7)
  #define is_epte_superpage(ept_entry)    ((ept_entry)->sp)
+#define is_epte_countable(ept_entry)    (is_epte_present(ept_entry) \
+                                         || ((ept_entry)->sa_p2mt == p2m_populate_on_demand))
 
  /* Non-ept "lock-and-check" wrapper */
  static int ept_pod_check_and_populate(struct p2m_domain *p2m, unsigned long gfn,

@@ -167,11 +169,14 @@
  void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry, int level)
  {
      /* End if the entry is a leaf entry. */
-    if ( level == 0 || !is_epte_present(ept_entry) ||
-         is_epte_superpage(ept_entry) )
+    if ( level == 0 || !is_epte_present(ept_entry) || is_epte_superpage(ept_entry) )
+    {
+        if ( is_epte_countable(ept_entry) )
+            p2m->stats.entries[level]--;
          return;
+    }
 
-    if ( level>  1 )
+    if ( level>  0 )
      {
          ept_entry_t *epte = map_domain_page(ept_entry->mfn);
          for ( int i = 0; i<  EPT_PAGETABLE_ENTRIES; i++ )

@@ -217,7 +222,10 @@
          ept_p2m_type_to_flags(epte, epte->sa_p2mt, epte->access);
 
          if ( (level - 1) == target )
+        {
+            p2m->stats.entries[target]++;
              continue;
+        }
 
          ASSERT(is_epte_superpage(epte));
 

@@ -400,6 +408,10 @@
              ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
          }
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
          atomic_write_ept_entry(ept_entry, new_entry);
      }
      else

@@ -412,12 +424,16 @@
 
          split_ept_entry = atomic_read_ept_entry(ept_entry);
 
+        /* Accounting should be OK here; split_ept_entry bump the counts,
+         * free_entry will reduce them. */
          if ( !ept_split_super_page(p2m,&split_ept_entry, i, target) )
          {
              ept_free_entry(p2m,&split_ept_entry, i);
              goto out;
          }
 
+        /* We know this was countable or we wouldn't be here.*/
+        p2m->stats.entries[i]--;
          /* now install the newly split ept sub-tree */
          /* NB: please make sure domian is paused and no in-fly VT-d DMA. */
          atomic_write_ept_entry(ept_entry, split_ept_entry);

@@ -449,9 +465,13 @@
 
          ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
          atomic_write_ept_entry(ept_entry, new_entry);
      }
-
+
      /* Track the highest gfn for which we have ever had a valid mapping */
      if ( mfn_valid(mfn_x(mfn))&&
           (gfn + (1UL<<  order) - 1>  p2m->max_mapped_pfn) )

diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/p2m.c

xen/arch/x86/mm/p2m.c Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c Thu May 05 17:40:34 2011 +0100 +42 -3

@@ -184,11 +184,15 @@
  {
      /* End if the entry is a leaf entry. */
      if ( page_order == 0
-         || !(l1e_get_flags(*p2m_entry)&  _PAGE_PRESENT)
+         || !(l1e_get_flags(*p2m_entry)&  _PAGE_PRESENT)
           || (l1e_get_flags(*p2m_entry)&  _PAGE_PSE) )
+    {
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
          return;
-
-    if ( page_order>  9 )
+    }
+
+    if ( page_order )
      {
          l1_pgentry_t *l3_table = map_domain_page(l1e_get_pfn(*p2m_entry));
          for ( int i = 0; i<  L3_PAGETABLE_ENTRIES; i++ )

@@ -242,6 +246,7 @@
          new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                   __PAGE_HYPERVISOR | _PAGE_USER);
 
+        /* Stats: Empty entry, no mods needed */
          switch ( type ) {
          case PGT_l3_page_table:
              p2m_add_iommu_flags(&new_entry, 3, IOMMUF_readable|IOMMUF_writable);

@@ -285,10 +290,12 @@
          {
              new_entry = l1e_from_pfn(pfn + (i * L1_PAGETABLE_ENTRIES), flags);
              p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable);
+            p2m->stats.entries[1]++;
              p2m->write_p2m_entry(p2m, gfn,
                  l1_entry+i, *table_mfn, new_entry, 2);
          }
          unmap_domain_page(l1_entry);
+        p2m->stats.entries[2]--;
          new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                   __PAGE_HYPERVISOR|_PAGE_USER); //disable PSE
          p2m_add_iommu_flags(&new_entry, 2, IOMMUF_readable|IOMMUF_writable);

@@ -320,6 +327,7 @@
          {
              new_entry = l1e_from_pfn(pfn + i, flags);
              p2m_add_iommu_flags(&new_entry, 0, 0);
+            p2m->stats.entries[0]++;
              p2m->write_p2m_entry(p2m, gfn,
                  l1_entry+i, *table_mfn, new_entry, 1);
          }

@@ -328,6 +336,7 @@
          new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                   __PAGE_HYPERVISOR|_PAGE_USER);
          p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable);
+        p2m->stats.entries[1]--;
          p2m->write_p2m_entry(p2m, gfn,
              p2m_entry, *table_mfn, new_entry, 2);
      }

@@ -908,6 +917,15 @@
  void
  p2m_pod_dump_data(struct p2m_domain *p2m)
  {
+    int i;
+    long entries;
+    printk("    P2M entry stats:\n");
+    for ( i=0; i<3; i++)
+        if ( (entries=p2m->stats.entries[i]) )
+            printk("     L%d: %8ld entries, %ld bytes\n",
+                   i+1,
+                   entries,
+                   entries<<(i*9+12));
      printk("    PoD entries=%d cachesize=%d\n",
             p2m->pod.entry_count, p2m->pod.count);
  }

@@ -1475,6 +1493,12 @@
              old_mfn = l1e_get_pfn(*p2m_entry);
          }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
          p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 3);
          /* NB: paging_write_p2m_entry() handles tlb flushes properly */
 

@@ -1519,6 +1543,13 @@
              p2m_add_iommu_flags(&entry_content, 0, iommu_pte_flags);
              old_mfn = l1e_get_pfn(*p2m_entry);
          }
+
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
          /* level 1 entry */
          p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 1);
          /* NB: paging_write_p2m_entry() handles tlb flushes properly */

@@ -1556,6 +1587,12 @@
              old_mfn = l1e_get_pfn(*p2m_entry);
          }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
          p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 2);
          /* NB: paging_write_p2m_entry() handles tlb flushes properly */
 

@@ -2750,6 +2787,8 @@
                  continue;
              }
 
+            /* STATS: Should change only type; no stats should need adjustment */
+
              l2mfn = _mfn(l3e_get_pfn(l3e[i3]));
              l2e = map_domain_page(l3e_get_pfn(l3e[i3]));
              for ( i2 = 0; i2<  L2_PAGETABLE_ENTRIES; i2++ )

diff -r 4b0692880dfa -r be5d93d38f28 xen/include/asm-x86/p2m.h

xen/include/asm-x86/p2m.h Fri May 06 15:01:08 2011 +0100 renamed from xen/include/asm-x86/p2m.h Thu May 05 17:40:34 2011 +0100 +4 -0

@@ -278,6 +278,10 @@
          unsigned         reclaim_single; /* Last gpfn of a scan */
          unsigned         max_guest;    /* gpfn of max guest demand-populate */
      } pod;
+
+    struct {
+        long entries[3];
+    } stats;
  };
 
  /* get host p2m table */

Quoted 5 lines

_______________________________________________
Xen-devel mailing list
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http://lists.xensource.com/xen-devel

--
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Advanced Micro Devices GmbH
Einsteinring 24, 85689 Dornach b. Muenchen
Geschaeftsfuehrer: Alberto Bozzo, Andrew Bowd
Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632

_______________________________________________
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[email protected]
http://lists.xensource.com/xen-devel

Hi,

Can you please add this:

[diff]
showfunc = True

There are two places where this patch changes the control flow of p2m operations:

Quoted 7 lines

xen/arch/x86/mm/hap/p2m-ept.c +0 -2

@@ -167,11 +169,14 @@
 void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry, int level)
 {
     /* End if the entry is a leaf entry. */
-    if ( level == 0 || !is_epte_present(ept_entry) ||
-         is_epte_superpage(ept_entry) )

xen/arch/x86/mm/hap/p2m-ept.c line 180

Quoted 10 lines

xen/arch/x86/mm/hap/p2m-ept.c +6 -1

+    if ( level == 0 || !is_epte_present(ept_entry) || is_epte_superpage(ept_entry) )
+    {
+        if ( is_epte_countable(ept_entry) )
+            p2m->stats.entries[level]--;
         return;
+    }
 
-    if ( level > 1 )
+    if ( level > 0 )
     {

and similarly:

Quoted 6 lines

xen/arch/x86/mm/p2m.c +1 -1

@@ -184,11 +184,15 @@
 {
     /* End if the entry is a leaf entry. */
     if ( page_order == 0
-         || !(l1e_get_flags(*p2m_entry) & _PAGE_PRESENT)
+         || !(l1e_get_flags(*p2m_entry) & _PAGE_PRESENT) 

xen/arch/x86/mm/p2m.c line 195

Quoted 10 lines

xen/arch/x86/mm/p2m.c +6 -2

          || (l1e_get_flags(*p2m_entry) & _PAGE_PSE) )
+    {
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
         return;
-
-    if ( page_order > 9 )
+    }
+
+    if ( page_order )

here. Can you explain those in a bit more detail?

Cheers,

Tim.

On the other hand, maybe the array itself could have a more descriptive name than "stats.entries".

What about this:

#define PAGE_ORDER_4K  0
#define PAGE_ORDER_2M  9
#define PAGE_ORDER_1G  18

Quoted 256 lines

On the other hand, maybe the array itself could have a more descriptive name than "stats.entries".

Tim.

Quoted 249 lines · George Dunlap

Quoted 248 lines

Count the number of 4kiB, 2MiB, and 1GiB p2m entries.

Signed-off-by George Dunlap<[email protected]>

diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/hap/p2m-ept.c

xen/arch/x86/mm/hap/p2m-ept.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c     Thu May 05 17:40:34 2011 +0100 +2 -0

@@ -39,6 +39,8 @@
 
   #define is_epte_present(ept_entry)      ((ept_entry)->epte&   0x7)
   #define is_epte_superpage(ept_entry)    ((ept_entry)->sp)
+#define is_epte_countable(ept_entry)    (is_epte_present(ept_entry) \
+                                         || ((ept_entry)->sa_p2mt ==
 p2m_populate_on_demand))
 
   /* Non-ept "lock-and-check" wrapper */

  static int ept_pod_check_and_populate(struct p2m_domain *p2m, unsigned long gfn,

xen/arch/x86/mm/hap/p2m-ept.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c     Thu May 05 17:40:34 2011 +0100 +6 -3

@@ -167,11 +169,14 @@
   void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry,
 int level)
   {
       /* End if the entry is a leaf entry. */
-    if ( level == 0 || !is_epte_present(ept_entry) ||
-         is_epte_superpage(ept_entry) )
+    if ( level == 0 || !is_epte_present(ept_entry) ||
 is_epte_superpage(ept_entry) )
+    {
+        if ( is_epte_countable(ept_entry) )
+            p2m->stats.entries[level]--;
           return;
+    }
 
-    if ( level>   1 )
+    if ( level>   0 )
       {

          ept_entry_t *epte = map_domain_page(ept_entry->mfn); for ( int i = 0; i<   EPT_PAGETABLE_ENTRIES; i++ )

xen/arch/x86/mm/hap/p2m-ept.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c     Thu May 05 17:40:34 2011 +0100 +7 -0

@@ -217,7 +222,10 @@
           ept_p2m_type_to_flags(epte, epte->sa_p2mt, epte->access);
 
           if ( (level - 1) == target )
+        {
+            p2m->stats.entries[target]++;
               continue;
+        }
 
           ASSERT(is_epte_superpage(epte));
 

@@ -400,6 +408,10 @@
               ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
           }
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
           atomic_write_ept_entry(ept_entry, new_entry);
       }

      else

xen/arch/x86/mm/hap/p2m-ept.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c     Thu May 05 17:40:34 2011 +0100 +4 -0

@@ -412,12 +424,16 @@
 
           split_ept_entry = atomic_read_ept_entry(ept_entry);
 
+        /* Accounting should be OK here; split_ept_entry bump the
 counts,
+         * free_entry will reduce them. */
           if ( !ept_split_super_page(p2m,&split_ept_entry, i, target) )
           {
               ept_free_entry(p2m,&split_ept_entry, i);
               goto out;
           }
 
+        /* We know this was countable or we wouldn't be here.*/
+        p2m->stats.entries[i]--;
           /* now install the newly split ept sub-tree */
           /* NB: please make sure domian is paused and no in-fly VT-d

DMA. */
          atomic_write_ept_entry(ept_entry, split_ept_entry);

xen/arch/x86/mm/hap/p2m-ept.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/hap/p2m-ept.c     Thu May 05 17:40:34 2011 +0100 +5 -1

@@ -449,9 +465,13 @@
 
           ept_p2m_type_to_flags(&new_entry, p2mt, p2ma);
 
+        /* old_entry will be handled by ept_free_entry below */
+        if ( is_epte_countable(&new_entry) )
+            p2m->stats.entries[i]++;
+
           atomic_write_ept_entry(ept_entry, new_entry);
       }
-
+
       /* Track the highest gfn for which we have ever had a valid

mapping */
      if ( mfn_valid(mfn_x(mfn))&&
           (gfn + (1UL<<   order) - 1>   p2m->max_mapped_pfn) ) diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/p2m.c

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +0 -0

@@ -184,11 +184,15 @@
   {
       /* End if the entry is a leaf entry. */

      if ( page_order == 0

-         || !(l1e_get_flags(*p2m_entry)&   _PAGE_PRESENT)
+         || !(l1e_get_flags(*p2m_entry)&   _PAGE_PRESENT)

           || (l1e_get_flags(*p2m_entry)&   _PAGE_PSE) )
+    {
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--; return;

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +3 -2

-
-    if ( page_order>   9 )
+    }
+
+    if ( page_order )

      {
          l1_pgentry_t *l3_table = map_domain_page(l1e_get_pfn(*p2m_entry));
          for ( int i = 0; i<   L3_PAGETABLE_ENTRIES; i++ )

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +1 -0

@@ -242,6 +246,7 @@
           new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                    __PAGE_HYPERVISOR | _PAGE_USER);
 
+        /* Stats: Empty entry, no mods needed */
           switch ( type ) {

          case PGT_l3_page_table:
              p2m_add_iommu_flags(&new_entry, 3,
IOMMUF_readable|IOMMUF_writable);

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +2 -0

@@ -285,10 +290,12 @@
           {
               new_entry = l1e_from_pfn(pfn + (i * L1_PAGETABLE_ENTRIES),
 flags);
               p2m_add_iommu_flags(&new_entry, 1,
 IOMMUF_readable|IOMMUF_writable);
+            p2m->stats.entries[1]++;
               p2m->write_p2m_entry(p2m, gfn,
                   l1_entry+i, *table_mfn, new_entry, 2);
           }
           unmap_domain_page(l1_entry);
+        p2m->stats.entries[2]--;
           new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),

                                   __PAGE_HYPERVISOR|_PAGE_USER); //disable PSE
          p2m_add_iommu_flags(&new_entry, 2, IOMMUF_readable|IOMMUF_writable);

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +2 -0

@@ -320,6 +327,7 @@
           {
               new_entry = l1e_from_pfn(pfn + i, flags);
               p2m_add_iommu_flags(&new_entry, 0, 0);
+            p2m->stats.entries[0]++;
               p2m->write_p2m_entry(p2m, gfn,
                   l1_entry+i, *table_mfn, new_entry, 1);
           }

@@ -328,6 +336,7 @@
           new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)),
                                    __PAGE_HYPERVISOR|_PAGE_USER);
           p2m_add_iommu_flags(&new_entry, 1,
 IOMMUF_readable|IOMMUF_writable);
+        p2m->stats.entries[1]--;
           p2m->write_p2m_entry(p2m, gfn,
               p2m_entry, *table_mfn, new_entry, 2);

      }

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +0 -0

@@ -908,6 +917,15 @@

  void
  p2m_pod_dump_data(struct p2m_domain *p2m)
  {
+    int i;
+    long entries;
+    printk("    P2M entry stats:\n");
+    for ( i=0; i<3; i++)
+        if ( (entries=p2m->stats.entries[i]) )
+            printk("     L%d: %8ld entries, %ld bytes\n",
+                   i+1,
+                   entries,
+                   entries<<(i*9+12));
      printk("    PoD entries=%d cachesize=%d\n", p2m->pod.entry_count, p2m->pod.count); }

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +6 -0

@@ -1475,6 +1493,12 @@
               old_mfn = l1e_get_pfn(*p2m_entry);
           }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
           p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn,
 entry_content, 3);
           /* NB: paging_write_p2m_entry() handles tlb flushes properly

*/

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +7 -0

@@ -1519,6 +1543,13 @@
               p2m_add_iommu_flags(&entry_content, 0, iommu_pte_flags);
               old_mfn = l1e_get_pfn(*p2m_entry);
           }
+
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
           /* level 1 entry */
           p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn,
 entry_content, 1);

          /* NB: paging_write_p2m_entry() handles tlb flushes properly */

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +6 -0

@@ -1556,6 +1587,12 @@
               old_mfn = l1e_get_pfn(*p2m_entry);
           }
 
+        /* Adjust count for present/not-present entries added */
+        if ( l1e_get_flags(*p2m_entry) )
+            p2m->stats.entries[page_order/9]--;
+        if ( l1e_get_flags(entry_content) )
+            p2m->stats.entries[page_order/9]++;
+
           p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn,
 entry_content, 2);
           /* NB: paging_write_p2m_entry() handles tlb flushes properly

*/

xen/arch/x86/mm/p2m.c     Fri May 06 15:01:08 2011 +0100 renamed from xen/arch/x86/mm/p2m.c     Thu May 05 17:40:34 2011 +0100 +1 -0

@@ -2750,6 +2787,8 @@
                   continue;
               }
 
+            /* STATS: Should change only type; no stats should need

adjustment */
+
              l2mfn = _mfn(l3e_get_pfn(l3e[i3])); l2e = map_domain_page(l3e_get_pfn(l3e[i3])); for ( i2 = 0; i2<   L2_PAGETABLE_ENTRIES; i2++ ) diff -r 4b0692880dfa -r be5d93d38f28 xen/include/asm-x86/p2m.h

xen/include/asm-x86/p2m.h Fri May 06 15:01:08 2011 +0100 renamed from xen/include/asm-x86/p2m.h Thu May 05 17:40:34 2011 +0100 +0 -0

@@ -278,6 +278,10 @@

          unsigned         reclaim_single; /* Last gpfn of a scan */ unsigned         max_guest;    /* gpfn of max guest demand-populate */
      } pod;
+
+    struct {
+        long entries[3];
+    } stats;
  };

Quoted 1 line

Quoted 1 line

Quoted 1 line

  /* get host p2m table */

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This patch is actually not necessary for the series -- just for the verification that it worked. I could drop this patch so we can discuss it, and send the other three by themselves (since they seem pretty uncontroversial).

Quoted 4 lines · George Dunlap

This patch is actually not necessary for the series -- just for the verification that it worked.  I could drop this patch so we can discuss it, and send the other three by themselves (since they seem pretty uncontroversial).

I think that's best.  I'll be looking at reference-counting p2m entries soon, I hope, and I'll add some bookkeeping when I do.  I suspect I can isolate it into a single place then.\

Quoted 6 lines · Tim Deegan

Quoted 4 lines · George Dunlap

This patch is actually not necessary for the series -- just for the verification that it worked.  I could drop this patch so we can discuss it, and send the other three by themselves (since they seem pretty uncontroversial).

Quoted 3 lines

I think that's best.  I'll be looking at reference-counting p2m entries soon, I hope, and I'll add some bookkeeping when I do.  I suspect I can isolate it into a single place then.\

Tim, I realize this is over a year ago now, but did you ever end up adding this bookkeeping? I'm trying to port this patch again...