handbook.htm

介绍操作系统的毕业论文

<span lang="EN-US">call_kernel(&amp;r);</span></p>
<p class="MsoNormalIndent" style="line-height: 125%">
<span style="font-family: 宋体">｝</span></p>
<h3 style="line-height: 125%"><!--mstheme--><font color="#666633"><span lang="EN-US">3</span><span style="font-family: 宋体">内核中系统功能调用的格式</span><!--mstheme--></font></h3>
<h3 style="line-height: 125%"><!--mstheme--><font color="#666633"><span lang="EN-US">3.1</span><span style="font-family: 宋体">线程迁移：</span><span lang="EN-US">0</span><span style="font-family: 宋体">号功能</span><!--mstheme--></font></h3>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">1.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">
功能：实现线程从一个进程迁移到另一个进程，线程在目标进程中从进程的初始执行点开始运行。通过线程返回系统功能调用，线程可以返回原来的进程中。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">2.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">格式：</span><span lang="EN-US">ax.</span><span style="font-family: 宋体">寄存器的值为零，</span><span lang="EN-US">bx</span><span style="font-family: 宋体">寄存器的绝对值为进程</span><span lang="EN-US">ID</span><span style="font-family: 宋体">。</span></p>
<p class="MsoNormal" style="text-indent: 23.75pt; line-height: 125%; margin-left: 42.0pt">
<span style="font-family: 宋体">如果当前的进程为管程，</span><span lang="EN-US">bx&gt;0</span><span style="font-family: 宋体">表示线程离开当前进程进入目标进程后，允许其它线程进入当前进程；</span><span lang="EN-US">bx 
&lt;0</span><span style="font-family: 宋体">表示即使线程迁移离开当前进程进入目标进程，也不允许其它线程进入当前进程，因此当线程从目标进程返回后，可以保证数据的一致性；</span><span lang="EN-US">bx</span><span style="font-family: 宋体">＝</span><span lang="EN-US">0</span><span style="font-family: 宋体">为非法。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">3.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">返回值：如果</span><span lang="EN-US">ax.</span><span style="font-family: 宋体">寄存器的值小于零，表示失败；否则，</span><span lang="EN-US">ax.</span><span style="font-family: 宋体">寄存器的值为同时返回了几次，因此如果大于零也表示失败；</span><span lang="EN-US">bx.</span><span style="font-family: 宋体">寄存器的值为</span><span lang="EN-US">TRUE</span><span style="font-family: 宋体">表示正常返回，为</span><span lang="EN-US">FALSE</span><span style="font-family: 宋体">表示异常返回（例如，线程在目标进程中运行时发生了不可恢复的异常而返回）。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">4.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">例：</span><span lang="EN-US">#include”../include/os.h”</span></p>
<p class="MsoNormalIndent" style="line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">{</span></p>
<p class="MsoNormalIndent" style="line-height: 125%"><span lang="EN-US">
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; REG r;</span></p>
<p class="MsoNormal" style="line-height: 125%; margin-left: 21.0pt">
<span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; r.ax=0;</span></p>
<p class="MsoNormal" style="text-indent: 21.0pt; line-height: 125%; margin-left: 63.0pt">
<span lang="EN-US">r.bx=2;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /*</span><span style="font-family: 宋体">迁移至２号进程，从其初始执行点开始运行</span></p>
<p class="MsoNormal" style="line-height: 125%; margin-left: 168.0pt">
<span style="font-family: 宋体">线程离开当前进程进入目标进程后，允许其它线程进入当前进程。</span><span lang="EN-US">*</span><span style="font-family: 宋体">／</span></p>
<p class="MsoNormal" style="line-height: 125%; margin-left: 21.0pt">
<span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; call_kernel(&amp;r);</span></p>
<p class="MsoNormal" style="line-height: 125%; margin-left: 21.0pt">
<span lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }</span></p>
<h3 style="line-height: 125%"><!--mstheme--><font color="#666633"><span lang="EN-US">3.2</span><span style="font-family: 宋体">线程迁移：</span><span lang="EN-US">1</span><span style="font-family: 宋体">号功能</span><!--mstheme--></font></h3>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">1.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">
功能：实现线程从一个进程迁移到另一个进程，线程在目标进程中从进程的初始执行点开始运行，和</span><span lang="EN-US">0</span><span style="font-family: 宋体">号功能不同的是：线程不能再次返回到原来的进程中。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">2.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">格式：</span><span lang="EN-US">ax.</span><span style="font-family: 宋体">寄存器的值为</span><span lang="EN-US">1</span><span style="font-family: 宋体">，</span><span lang="EN-US">bx</span><span style="font-family: 宋体">寄存器的绝对值为进程</span><span lang="EN-US">ID</span><span style="font-family: 宋体">。</span></p>
<p class="MsoNormal" style="text-indent: 23.75pt; line-height: 125%; margin-left: 42.0pt">
<span style="font-family: 宋体">如果当前的进程为管程，</span><span lang="EN-US">bx&gt;0</span><span style="font-family: 宋体">表示线程离开当前进程进入目标进程后，允许其它线程进入当前进程；</span><span lang="EN-US">bx 
&lt;0</span><span style="font-family: 宋体">表示即使线程迁移离开当前进程进入目标进程，也不允许其它线程进入当前进程。只有对当前进程的管程信号量执行</span><span lang="EN-US">V</span><span style="font-family: 宋体">操作，才能允许其它线程进入当前进程；</span><span lang="EN-US">bx</span><span style="font-family: 宋体">＝</span><span lang="EN-US">0</span><span style="font-family: 宋体">为非法。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">3.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">返回值：如果执行成功，线程不可能返回，返回则表示失败。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">4.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">例：</span><span lang="EN-US">#include”../include/os.h”</span></p>
<p class="MsoNormalIndent" style="line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">{</span></p>
<p class="MsoNormal" style="text-indent: 21.0pt; line-height: 125%; margin-left: 63.0pt">
<span lang="EN-US">REG r;</span></p>
<p class="MsoNormal" style="text-indent: 21.0pt; line-height: 125%; margin-left: 63.0pt">
<span lang="EN-US">r.ax=1;</span></p>
<p class="MsoNormal" style="text-indent: 21.0pt; line-height: 125%; margin-left: 63.0pt">
<span lang="EN-US">r.bx=(-2);&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /*</span><span style="font-family: 宋体">迁移至２号进程，从其初始执行点开始运行</span></p>
<p class="MsoNormal" style="line-height: 125%; margin-left: 168.0pt">
<span style="font-family: 宋体">线程离开当前进程进入目标进程后，不允许其它线程进入当前进程。</span><span lang="EN-US">*</span><span style="font-family: 宋体">／</span></p>
<p class="MsoNormal" style="text-indent: 21.0pt; line-height: 125%; margin-left: 63.0pt">
<span lang="EN-US">call_kernel(&amp;r);</span></p>
<p class="MsoNormalIndent" style="line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">}</span></p>
<h3 style="line-height: 125%"><!--mstheme--><font color="#666633"><span lang="EN-US">3.3 </span>
<span style="font-family: 宋体">线程迁移（修改线程可以访问的物理页框）：</span><span lang="EN-US">2</span><span style="font-family: 宋体">号功能</span><!--mstheme--></font></h3>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">1.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">功能：线程迁移（修改线程可以访问的物理页框）。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">2.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">格式：</span><span lang="EN-US">ax.</span><span style="font-family: 宋体">寄存器的值为</span><span lang="EN-US">2</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 63.0pt">
<span lang="EN-US" style="font-family: Wingdings">l<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span lang="EN-US">cx</span><span style="font-family: 宋体">寄存器存放存储体</span><span lang="EN-US">ID</span><span style="font-family: 宋体">，</span><span lang="EN-US">dx</span><span style="font-family: 宋体">寄存器存放参数页框</span><span lang="EN-US">ID</span><span style="font-family: 宋体">，</span><span lang="EN-US">si</span><span style="font-family: 宋体">寄存器存放线程可以直接访问的物理页框</span><span lang="EN-US">ID</span><span style="font-family: 宋体">，其它参数和格式同</span><span lang="EN-US">0</span><span style="font-family: 宋体">号功能。</span></p>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">
<span lang="EN-US">3.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</span></span><span style="font-family: 宋体">返回值：同</span><span lang="EN-US">0</span><span style="font-family: 宋体">号功能</span></p>
<h3 style="line-height: 125%"><!--mstheme--><font color="#666633"><span lang="EN-US">3.4</span><span style="font-family: 宋体">线程返回：</span><span lang="EN-US">3</span><span style="font-family: 宋体">号功能</span><!--mstheme--></font></h3>
<p class="MsoNormal" style="text-indent: -21.0pt; line-height: 125%; margin-left: 42.0pt">