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+>Thread priorities</TITLE
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+><H1
+><A
+NAME="KERNEL-THREAD-PRIORITIES">Thread priorities</H1
+><DIV
+CLASS="REFNAMEDIV"
+><A
+NAME="AEN616"
+></A
+><H2
+>Name</H2
+>cyg_thread_get_priority, cyg_thread_get_current_priority, cyg_thread_set_priority -- Examine and manipulate thread priorities</DIV
+><DIV
+CLASS="REFSYNOPSISDIV"
+><A
+NAME="AEN621"><H2
+>Synopsis</H2
+><DIV
+CLASS="FUNCSYNOPSIS"
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+NAME="AEN622"><P
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+><TD
+><PRE
+CLASS="FUNCSYNOPSISINFO"
+>#include <cyg/kernel/kapi.h>
+ </PRE
+></TD
+></TR
+></TABLE
+><P
+><CODE
+><CODE
+CLASS="FUNCDEF"
+>cyg_priority_t cyg_thread_get_priority</CODE
+>(cyg_handle_t thread);</CODE
+></P
+><P
+><CODE
+><CODE
+CLASS="FUNCDEF"
+>cyg_priority_t cyg_thread_get_current_priority</CODE
+>(cyg_handle_t thread);</CODE
+></P
+><P
+><CODE
+><CODE
+CLASS="FUNCDEF"
+>void cyg_thread_set_priority</CODE
+>(cyg_handle_t thread, cyg_priority_t priority);</CODE
+></P
+><P
+></P
+></DIV
+></DIV
+><DIV
+CLASS="REFSECT1"
+><A
+NAME="AEN641"
+></A
+><H2
+>Description</H2
+><P
+>Typical schedulers use the concept of a thread priority to determine
+which thread should run next. Exactly what this priority consists of
+will depend on the scheduler, but a typical implementation would be a
+small integer in the range 0 to 31, with 0 being the highest priority.
+Usually only the idle thread will run at the lowest priority. The
+exact number of priority levels available depends on the
+configuration, typically the option
+<TT
+CLASS="VARNAME"
+>CYGNUM_KERNEL_SCHED_PRIORITIES</TT
+>.
+ </P
+><P
+><TT
+CLASS="FUNCTION"
+>cyg_thread_get_priority</TT
+> can be used to determine
+the priority of a thread, or more correctly the value last used in a
+<TT
+CLASS="FUNCTION"
+>cyg_thread_set_priority</TT
+> call or when the thread
+was first created. In some circumstances it is possible that the
+thread is actually running at a higher priority. For example, if it
+owns a mutex and priority ceilings or inheritance is being used to
+prevent priority inversion problems, then the thread's priority may
+have been boosted temporarily.
+<TT
+CLASS="FUNCTION"
+>cyg_thread_get_current_priority</TT
+> returns the real
+current priority.
+ </P
+><P
+>In many applications appropriate thread priorities can be determined
+and allocated statically. However, if it is necessary for a thread's
+priority to change at run-time then the
+<TT
+CLASS="FUNCTION"
+>cyg_thread_set_priority</TT
+> function provides this
+functionality.
+ </P
+></DIV
+><DIV
+CLASS="REFSECT1"
+><A
+NAME="KERNEL-THREAD-PRIORITIES-CONTEXT"
+></A
+><H2
+>Valid contexts</H2
+><P
+><TT
+CLASS="FUNCTION"
+>cyg_thread_get_priority</TT
+> and
+<TT
+CLASS="FUNCTION"
+>cyg_thread_get_current_priority</TT
+> can be called
+from thread or DSR context, although the latter is rarely useful.
+<TT
+CLASS="FUNCTION"
+>cyg_thread_set_priority</TT
+> should also only be
+called from thread context.
+ </P
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