| 465,7 → 465,25 |
|---|
| levels can be left out, depending on the hardware hierachy or |
| structure of software-only page tables. The genericity is achieved |
| through a set of macros that define transitions from one level to |
| another. Unused levels are optimised out by the compiler.</para> |
| another. Unused levels are optimised out by the compiler. |
| <figure float="1"> |
| <mediaobject id="mm_pt"> |
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| <imagedata fileref="images/mm_pt.pdf" format="PDF" /> |
| </imageobject> |
| |
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| <imageobject role="fop"> |
| <imagedata fileref="images/mm_pt.svg" format="SVG" /> |
| </imageobject> |
| </mediaobject> |
| |
| <title>Hierarchical 4-level page tables.</title> |
| </figure> |
| </para> |
| </section> |
| |
| <section> |
| 488,8 → 506,26 |
|---|
| there is only a single global page hash table in the system while |
| hierarchical page tables exist per address space. Thus, the global |
| page hash table contains information about mappings of all address |
| spaces in the system.</para> |
| spaces in the system. |
| <figure float="1"> |
| <mediaobject id="mm_hash"> |
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| </imageobject> |
| |
| <imageobject role="fop"> |
| <imagedata fileref="images/mm_hash.svg" format="SVG" /> |
| </imageobject> |
| </mediaobject> |
| |
| <title>Global page hash table.</title> |
| </figure> |
| </para> |
| |
| <para>The global page hash table mechanism uses the generic hash table |
| type as described in the chapter dedicated to <link |
| linkend="hashtables">data structures</link> earlier in this |