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diff --git a/static/freebsd/man9/kthread.9 3.html b/static/freebsd/man9/kthread.9 3.html deleted file mode 100644 index 01aa3362..00000000 --- a/static/freebsd/man9/kthread.9 3.html +++ /dev/null @@ -1,271 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">KTHREAD(9)</td> - <td class="head-vol">Kernel Developer's Manual</td> - <td class="head-rtitle">KTHREAD(9)</td> - </tr> -</table> -<div class="manual-text"> -<section class="Sh"> -<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> -<p class="Pp"><code class="Nm">kthread_start</code>, - <code class="Nm">kthread_shutdown</code>, - <code class="Nm">kthread_add</code>, <code class="Nm">kthread_exit</code>, - <code class="Nm">kthread_resume</code>, - <code class="Nm">kthread_suspend</code>, - <code class="Nm">kthread_suspend_check</code> — - <span class="Nd">kernel threads</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp"><code class="In">#include - <<a class="In">sys/kthread.h</a>></code></p> -<p class="Pp"><var class="Ft">void</var> - <br/> - <code class="Fn">kthread_start</code>(<var class="Fa" style="white-space: nowrap;">const - void *udata</var>);</p> -<p class="Pp"><var class="Ft">void</var> - <br/> - <code class="Fn">kthread_shutdown</code>(<var class="Fa" style="white-space: nowrap;">void - *arg</var>, <var class="Fa" style="white-space: nowrap;">int - howto</var>);</p> -<p class="Pp"><var class="Ft">void</var> - <br/> - <code class="Fn">kthread_exit</code>(<var class="Fa" style="white-space: nowrap;">void</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">kthread_resume</code>(<var class="Fa" style="white-space: nowrap;">struct - thread *td</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">kthread_suspend</code>(<var class="Fa" style="white-space: nowrap;">struct - thread *td</var>, <var class="Fa" style="white-space: nowrap;">int - timo</var>);</p> -<p class="Pp"><var class="Ft">void</var> - <br/> - <code class="Fn">kthread_suspend_check</code>(<var class="Fa" style="white-space: nowrap;">void</var>);</p> -<p class="Pp"><code class="In">#include - <<a class="In">sys/unistd.h</a>></code></p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">kthread_add</code>(<var class="Fa">void (*func)(void - *)</var>, <var class="Fa">void *arg</var>, <var class="Fa">struct proc - *procp</var>, <var class="Fa">struct thread **newtdpp</var>, - <var class="Fa">int flags</var>, <var class="Fa">int pages</var>, - <var class="Fa">const char *fmt</var>, <var class="Fa">...</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">kproc_kthread_add</code>(<var class="Fa">void (*func)(void - *)</var>, <var class="Fa">void *arg</var>, <var class="Fa">struct proc - **procptr</var>, <var class="Fa">struct thread **tdptr</var>, - <var class="Fa">int flags</var>, <var class="Fa">int pages</var>, - <var class="Fa">char * procname</var>, <var class="Fa">const char - *fmt</var>, <var class="Fa">...</var>);</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">In <span class="Ux">FreeBSD 8.0</span>, the older family of - <a class="permalink" href="#kthread_*"><code class="Fn" id="kthread_*">kthread_*</code></a>(<var class="Fa">9</var>) - functions was renamed to be the - <a class="permalink" href="#kproc_*"><code class="Fn" id="kproc_*">kproc_*</code></a>(<var class="Fa">9</var>) - family of functions, as they were previously misnamed and actually produced - kernel processes. This new family of - <code class="Fn">kthread_*</code>(<var class="Fa">9</var>) functions was - added to produce - <a class="permalink" href="#real"><i class="Em" id="real">real</i></a> - kernel threads. See the <a class="Xr">kproc(9)</a> man page for more - information on the renamed calls. Also note that the - <code class="Fn">kproc_kthread_add</code>(<var class="Fa">9</var>) function - appears in both pages as its functionality is split.</p> -<p class="Pp" id="kthread_start">The function - <a class="permalink" href="#kthread_start"><code class="Fn">kthread_start</code></a>() - is used to start “internal” daemons such as - <code class="Nm">bufdaemon</code>, <code class="Nm">pagedaemon</code>, - <code class="Nm">vmdaemon</code>, and the <code class="Nm">syncer</code> and - is intended to be called from <a class="Xr">SYSINIT(9)</a>. The - <var class="Fa">udata</var> argument is actually a pointer to a - <var class="Vt">struct kthread_desc</var> which describes the kernel thread - that should be created:</p> -<div class="Bd Pp Bd-indent Li"> -<pre>struct kthread_desc { - char *arg0; - void (*func)(void); - struct thread **global_threadpp; -};</pre> -</div> -<p class="Pp" id="kthread_start~2">The structure members are used by - <a class="permalink" href="#kthread_start~2"><code class="Fn">kthread_start</code></a>() - as follows:</p> -<div class="Bd-indent"> -<dl class="Bl-tag"> - <dt id="arg0"><var class="Va">arg0</var></dt> - <dd>String to be used for the name of the thread. This string will be copied - into the <var class="Va">td_name</var> member of the new threads' - <var class="Vt">struct thread</var>.</dd> - <dt id="func"><var class="Va">func</var></dt> - <dd>The main function for this kernel thread to run.</dd> - <dt id="global_threadpp"><var class="Va">global_threadpp</var></dt> - <dd>A pointer to a <var class="Vt">struct thread</var> pointer that should be - updated to point to the newly created thread's - <var class="Vt">thread</var> structure. If this variable is - <code class="Dv">NULL</code>, then it is ignored. The thread will be a - subthread of <var class="Va">proc0</var> (PID 0).</dd> -</dl> -</div> -<p class="Pp" id="kthread_add">The - <a class="permalink" href="#kthread_add"><code class="Fn">kthread_add</code></a>() - function is used to create a kernel thread. The new thread runs in kernel - mode only. It is added to the process specified by the - <var class="Fa">procp</var> argument, or if that is - <code class="Dv">NULL</code>, to <var class="Va">proc0</var>. The - <var class="Fa">func</var> argument specifies the function that the thread - should execute. The <var class="Fa">arg</var> argument is an arbitrary - pointer that is passed in as the only argument to <var class="Fa">func</var> - when it is called by the new thread. The <var class="Fa">newtdpp</var> - pointer points to a <var class="Vt">struct thread</var> pointer that is to - be updated to point to the newly created thread. If this argument is - <code class="Dv">NULL</code>, then it is ignored. The - <var class="Fa">flags</var> argument may be set to - <code class="Dv">RFSTOPPED</code> to leave the thread in a stopped state. - The caller must call - <a class="permalink" href="#sched_add"><code class="Fn" id="sched_add">sched_add</code></a>() - to start the thread. The <var class="Fa">pages</var> argument specifies the - size of the new kernel thread's stack in pages. If 0 is used, the default - kernel stack size is allocated. The rest of the arguments form a - <a class="Xr">printf(9)</a> argument list that is used to build the name of - the new thread and is stored in the <var class="Va">td_name</var> member of - the new thread's <var class="Vt">struct thread</var>.</p> -<p class="Pp" id="kproc_kthread_add">The - <a class="permalink" href="#kproc_kthread_add"><code class="Fn">kproc_kthread_add</code></a>() - function is much like the <code class="Fn">kthread_add</code>() function - above except that if the kproc does not already exist, it is created. This - function is better documented in the <a class="Xr">kproc(9)</a> manual - page.</p> -<p class="Pp" id="kthread_exit">The - <a class="permalink" href="#kthread_exit"><code class="Fn">kthread_exit</code></a>() - function is used to terminate kernel threads. It should be called by the - main function of the kernel thread rather than letting the main function - return to its caller.</p> -<p class="Pp" id="kthread_resume">The - <a class="permalink" href="#kthread_resume"><code class="Fn">kthread_resume</code></a>(), - <a class="permalink" href="#kthread_suspend"><code class="Fn" id="kthread_suspend">kthread_suspend</code></a>(), - and - <a class="permalink" href="#kthread_suspend_check"><code class="Fn" id="kthread_suspend_check">kthread_suspend_check</code></a>() - functions are used to suspend and resume a kernel thread. During the main - loop of its execution, a kernel thread that wishes to allow itself to be - suspended should call <code class="Fn">kthread_suspend_check</code>() in - order to check if the it has been asked to suspend. If it has, it will - <a class="Xr">msleep(9)</a> until it is told to resume. Once it has been - told to resume it will return allowing execution of the kernel thread to - continue. The other two functions are used to notify a kernel thread of a - suspend or resume request. The <var class="Fa">td</var> argument points to - the <var class="Vt">struct thread</var> of the kernel thread to suspend or - resume. For <code class="Fn">kthread_suspend</code>(), the - <var class="Fa">timo</var> argument specifies a timeout to wait for the - kernel thread to acknowledge the suspend request and suspend itself.</p> -<p class="Pp" id="kthread_shutdown">The - <a class="permalink" href="#kthread_shutdown"><code class="Fn">kthread_shutdown</code></a>() - function is meant to be registered as a shutdown event for kernel threads - that need to be suspended voluntarily during system shutdown so as not to - interfere with system shutdown activities. The actual suspension of the - kernel thread is done with - <a class="permalink" href="#kthread_suspend~2"><code class="Fn" id="kthread_suspend~2">kthread_suspend</code></a>().</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="RETURN_VALUES"><a class="permalink" href="#RETURN_VALUES">RETURN - VALUES</a></h1> -<p class="Pp">The <code class="Fn">kthread_add</code>(), - <code class="Fn">kthread_resume</code>(), and - <code class="Fn">kthread_suspend</code>() functions return zero on success - and non-zero on failure.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1> -<p class="Pp">This example demonstrates the use of a <var class="Vt">struct - kthread_desc</var> and the functions - <code class="Fn">kthread_start</code>(), - <code class="Fn">kthread_shutdown</code>(), and - <code class="Fn">kthread_suspend_check</code>() to run the - <code class="Nm">bufdaemon</code> process.</p> -<div class="Bd Pp Bd-indent Li"> -<pre>static struct thread *bufdaemonthread; - -static struct kthread_desc buf_kp = { - "bufdaemon", - buf_daemon, - &bufdaemonthread -}; -SYSINIT(bufdaemon, SI_SUB_KTHREAD_BUF, SI_ORDER_FIRST, kthread_start, - &buf_kp) - -static void -buf_daemon() -{ - ... - /* - * This process needs to be suspended prior to shutdown sync. - */ - EVENTHANDLER_REGISTER(shutdown_pre_sync, kthread_shutdown, - bufdaemonthread, SHUTDOWN_PRI_LAST); - ... - for (;;) { - kthread_suspend_check(); - ... - } -}</pre> -</div> -</section> -<section class="Sh"> -<h1 class="Sh" id="ERRORS"><a class="permalink" href="#ERRORS">ERRORS</a></h1> -<p class="Pp">The <code class="Fn">kthread_resume</code>() and - <code class="Fn">kthread_suspend</code>() functions will fail if:</p> -<dl class="Bl-tag"> - <dt id="EINVAL">[<a class="permalink" href="#EINVAL"><code class="Er">EINVAL</code></a>]</dt> - <dd>The <var class="Fa">td</var> argument does not reference a kernel - thread.</dd> -</dl> -<p class="Pp">The <code class="Fn">kthread_add</code>() function will fail - if:</p> -<dl class="Bl-tag"> - <dt id="ENOMEM">[<a class="permalink" href="#ENOMEM"><code class="Er">ENOMEM</code></a>]</dt> - <dd>Memory for a thread's stack could not be allocated.</dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE - ALSO</a></h1> -<p class="Pp"><a class="Xr">kproc(9)</a>, <a class="Xr">SYSINIT(9)</a>, - <a class="Xr">wakeup(9)</a></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> -<p class="Pp">The <code class="Fn">kthread_start</code>() function first - appeared in <span class="Ux">FreeBSD 2.2</span> where it created a whole - process. It was converted to create threads in <span class="Ux">FreeBSD - 8.0</span>. The <code class="Fn">kthread_shutdown</code>(), - <code class="Fn">kthread_exit</code>(), - <code class="Fn">kthread_resume</code>(), - <code class="Fn">kthread_suspend</code>(), and - <code class="Fn">kthread_suspend_check</code>() functions were introduced in - <span class="Ux">FreeBSD 4.0</span> and were converted to threads in - <span class="Ux">FreeBSD 8.0</span>. The - <code class="Fn">kthread_create</code>() call was renamed to - <code class="Fn">kthread_add</code>() in <span class="Ux">FreeBSD - 8.0</span>. The old functionality of creating a kernel process was renamed - to <a class="Xr">kproc_create(9)</a>. Prior to <span class="Ux">FreeBSD - 5.0</span>, the <code class="Fn">kthread_shutdown</code>(), - <code class="Fn">kthread_resume</code>(), - <code class="Fn">kthread_suspend</code>(), and - <code class="Fn">kthread_suspend_check</code>() functions were named - <code class="Fn">shutdown_kproc</code>(), - <code class="Fn">resume_kproc</code>(), - <code class="Fn">shutdown_kproc</code>(), and - <code class="Fn">kproc_suspend_loop</code>(), respectively.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">July 15, 2014</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |