Revert "ST: Remove context switch callback."

This reverts commit 708bca4.
winlinvip · Aug 20, 2024 · 61516ad · 61516ad
1 parent a0b49ae
commit 61516ad
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diff --git a/trunk/3rdparty/st-srs/common.c b/trunk/3rdparty/st-srs/common.c
@@ -33,11 +33,14 @@ void st_clist_insert_after(_st_clist_t *e, _st_clist_t *l)
 
 void _st_switch_context(_st_thread_t *thread)
 {
+    ST_SWITCH_OUT_CB(thread);
+
     if (!_st_md_cxt_save(thread->context)) {
         _st_vp_schedule();
     }
 
     ST_DEBUG_ITERATE_THREADS();
+    ST_SWITCH_IN_CB(thread);
 }
 
 void _st_restore_context(_st_thread_t *thread)

diff --git a/trunk/3rdparty/st-srs/common.h b/trunk/3rdparty/st-srs/common.h
@@ -198,6 +198,11 @@ typedef struct _st_vp {
 
     _st_thread_t *sleep_q;      /* sleep queue for this vp */
     int sleepq_size;          /* number of threads on sleep queue */
+
+#ifdef ST_SWITCH_CB
+    st_switch_cb_t switch_out_cb;    /* called when a thread is switched out */
+    st_switch_cb_t switch_in_cb;    /* called when a thread is switched in */
+#endif
 } _st_vp_t;
 
 
@@ -296,6 +301,24 @@ extern __thread _st_eventsys_t *_st_eventsys;
     #define ST_DEBUG_ITERATE_THREADS()
 #endif
 
+#ifdef ST_SWITCH_CB
+    #define ST_SWITCH_OUT_CB(_thread)        \
+        if (_st_this_vp.switch_out_cb != NULL &&    \
+            _thread != _st_this_vp.idle_thread &&    \
+            _thread->state != _ST_ST_ZOMBIE) {    \
+          _st_this_vp.switch_out_cb();        \
+        }
+    #define ST_SWITCH_IN_CB(_thread)        \
+        if (_st_this_vp.switch_in_cb != NULL &&    \
+        _thread != _st_this_vp.idle_thread &&    \
+        _thread->state != _ST_ST_ZOMBIE) {    \
+          _st_this_vp.switch_in_cb();        \
+        }
+#else
+    #define ST_SWITCH_OUT_CB(_thread)
+    #define ST_SWITCH_IN_CB(_thread)
+#endif
+
 /*
  * Switch away from the current thread context by saving its state and
  * calling the thread scheduler

diff --git a/trunk/3rdparty/st-srs/docs/reference.html b/trunk/3rdparty/st-srs/docs/reference.html
@@ -13,6 +13,7 @@ <H2>State Threads Library Reference</H2>
 <DL><DD><A HREF=#mutex_t>st_mutex_t</A></DD></DL>
 <DL><DD><A HREF=#utime_t>st_utime_t</A></DD></DL>
 <DL><DD><A HREF=#netfd_t>st_netfd_t</A></DD></DL>
+<DL><DD><A HREF=#switch_cb_t>st_switch_cb_t</A></DD></DL>
 <P>
 <DD><A HREF=#errors><B>Error Handling</B></A></DD>
 <P>
@@ -27,6 +28,10 @@ <H2>State Threads Library Reference</H2>
 <DL><DD><A HREF=#timecache_set>st_timecache_set()</A></DD></DL>
 <DL><DD><A HREF=#randomize_stacks>st_randomize_stacks()</A></DD></DL>
 <P>
+<DL><DD><A HREF=#switch_cb_t><B>st_switch_cb_t</B> type</A></DD></DL>
+<DL><DD><A HREF=#set_switch_in_cb>st_set_switch_in_cb()</A></DD></DL>
+<DL><DD><A HREF=#set_switch_out_cb>st_set_switch_out_cb()</A></DD></DL>
+<P>
 <DD><A HREF=#threads><B>Thread Control and Identification</B></A></DD>
 <P>
 <DL><DD><A HREF=#thread_t><B>st_thread_t</B> type</A></DD></DL>
@@ -256,6 +261,31 @@ <H5>Description</H5>
 <HR>
 <P>
 
+<A NAME="switch_cb_t">
+<H4>st_switch_cb_t</H4>
+</A>
+Context switch callback function type.
+<P>
+<H5>Syntax</H5>
+
+<PRE>
+#include &lt;st.h&gt;
+
+typedef void (*st_switch_cb_t)(void);
+</PRE>
+<P>
+<H5>Description</H5>
+
+This datatype is a convenience type for describing a pointer
+to a function that will be called when a thread is set to stop
+or set to run.
+This feature is available only when <TT>ST_SWITCH_CB</TT> is defined
+in <TT>&lt;st.h&gt;</TT>.
+
+<P>
+<HR>
+<P>
+
 <A NAME="errors">
 <H2>Error Handling</H2>
 </A>
@@ -282,6 +312,11 @@ <H2>Library Initialization</H2>
 <DD><A HREF=#set_eventsys>st_set_eventsys()</A></DD>
 <DD><A HREF=#get_eventsys>st_get_eventsys()</A></DD>
 <DD><A HREF=#get_eventsys_name>st_get_eventsys_name()</A></DD>
+<P>
+These functions operate on a callback function of type
+<A HREF=#switch_cb_t><B>st_switch_cb_t</B></A>:
+<DD><A HREF=#set_switch_in_cb>st_set_switch_in_cb()</A></DD>
+<DD><A HREF=#set_switch_out_cb>st_set_switch_out_cb()</A></DD>
 </DL>
 <P>
 <HR>
@@ -500,6 +535,44 @@ <H5>Description</H5>
 <HR>
 <P>
 
+<A NAME="set_switch_in_cb">
+<H4>st_set_switch_in_cb()</H4>
+</A>
+<A NAME="set_switch_out_cb">
+<H4>st_set_switch_out_cb()</H4>
+</A>
+Set the optional callback function for thread switches.
+<P>
+<H5>Syntax</H5>
+
+<PRE>
+#include &lt;st.h&gt;
+
+st_switch_cb_t st_set_switch_in_cb(st_switch_cb_t cb);
+st_switch_cb_t st_set_switch_out_cb(st_switch_cb_t cb);
+</PRE>
+<P>
+<H5>Parameters</H5>
+<TT>st_set_switch_in_cb()</TT> and <TT>st_set_switch_out_cb()</TT> have the
+following parameter:<P>
+<TT>cb</TT><P>
+A function to be called when a thread is resumed and stopped respectively.<P>
+<H5>Returns</H5>
+The previous callback function pointer.
+<P>
+<H5>Description</H5>
+These functions set the callback for when a thread is resumed and stopped
+respectively.  After being called any thread switch will call the callback.
+Use a <TT>NULL</TT> pointer to disable the callback (this is the default).
+Use <A HREF=#thread_self>st_thread_self()</A> or <A HREF=#priv>thread
+specific data</A> to differentiate between threads.<P>
+These functions can be called at any time.<P>
+This feature is available only when <TT>ST_SWITCH_CB</TT> is defined
+in <TT>&lt;st.h&gt;</TT>.
+<P>
+<HR>
+<P>
+
 <A NAME="threads">
 <H2>Thread Control and Identification</H2>
 </A>

diff --git a/trunk/3rdparty/st-srs/public.h b/trunk/3rdparty/st-srs/public.h
@@ -51,6 +51,9 @@
 #define ST_VERSION_MAJOR    1
 #define ST_VERSION_MINOR    9
 
+/* Undefine this to remove the context switch callback feature. */
+#define ST_SWITCH_CB
+
 #ifndef ETIME
     #define ETIME ETIMEDOUT
 #endif
@@ -76,6 +79,9 @@ typedef struct _st_thread * st_thread_t;
 typedef struct _st_cond *   st_cond_t;
 typedef struct _st_mutex *  st_mutex_t;
 typedef struct _st_netfd *  st_netfd_t;
+#ifdef ST_SWITCH_CB
+typedef void (*st_switch_cb_t)(void);
+#endif
 
 extern int st_init(void);
 extern int st_getfdlimit(void);
@@ -84,6 +90,11 @@ extern int st_set_eventsys(int eventsys);
 extern int st_get_eventsys(void);
 extern const char *st_get_eventsys_name(void);
 
+#ifdef ST_SWITCH_CB
+extern st_switch_cb_t st_set_switch_in_cb(st_switch_cb_t cb);
+extern st_switch_cb_t st_set_switch_out_cb(st_switch_cb_t cb);
+#endif
+
 extern st_thread_t st_thread_self(void);
 extern void st_thread_exit(void *retval);
 extern int st_thread_join(st_thread_t thread, void **retvalp);

diff --git a/trunk/3rdparty/st-srs/sched.c b/trunk/3rdparty/st-srs/sched.c
@@ -238,6 +238,23 @@ void st_destroy(void)
 }
 
 
+#ifdef ST_SWITCH_CB
+st_switch_cb_t st_set_switch_in_cb(st_switch_cb_t cb)
+{
+    st_switch_cb_t ocb = _st_this_vp.switch_in_cb;
+    _st_this_vp.switch_in_cb = cb;
+    return ocb;
+}
+
+st_switch_cb_t st_set_switch_out_cb(st_switch_cb_t cb)
+{
+    st_switch_cb_t ocb = _st_this_vp.switch_out_cb;
+    _st_this_vp.switch_out_cb = cb;
+    return ocb;
+}
+#endif
+
+
 /*
  * Start function for the idle thread
  */