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<DIV><FONT face=Arial size=2>During porting a protocol stack to RTEMS, I found
there is a callback function which is used</FONT></DIV>
<DIV><FONT face=Arial size=2>to handle reveiving HDLC frame from driver layer,
it contains malloc() function call internally.</FONT></DIV>
<DIV><FONT face=Arial size=2>After looking </FONT><FONT face=Arial
size=2>through RTEMS document, I found rtems_region_get_segment() isn't in
</FONT><FONT face=Arial size=2>the list</FONT></DIV>
<DIV><FONT face=Arial size=2>of directives allowed from ISR. So I wonder whether
this callback function can be called</FONT></DIV>
<DIV><FONT face=Arial size=2>directly in driver's ISR or the driver create a
receive daemon task and invoke this callback</FONT></DIV>
<DIV><FONT face=Arial size=2>function in the task(this is more time
consuming).</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Furthermore, can anybody explains the protection
mechanisms used by RTEMS supercore </FONT></DIV>
<DIV><FONT face=Arial size=2>to implement mutual exclusion with minimum
interrupt latency, both among tasks and ISR.</FONT></DIV>
<DIV><FONT face=Arial size=2>I can't find any document about this. Before
hacking source code, I want a brief introduciton.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Any help is appreciated !</FONT></DIV>
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