From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Sat, 28 Jan 2006 10:34:41 +0100
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: [Xenomai-core] [PATCH] fix pthread cancellation in native skin
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Hi,

Gilles' work on cancellation for the posix skin reminded me of this
issue I once discovered in the native skin:

https://mail.gna.org/public/xenomai-core/2005-12/msg00014.html

I found out that this can easily be fixed by switching the pthread of a
native task to PTHREAD_CANCEL_ASYNCHRONOUS. See attached patch.


At this chance I discovered that calling rt_task_delete for a task that
was created and started with T_SUSP mode but was not yet resumed, locks
up the system. More precisely: it raises a fatal warning when
XENO_OPT_DEBUG is on. Might be the case that it just works on system
without this switched on. Either this is a real bug, or the warning
needs to be fixed. (Deleting a task after rt_task_suspend works.)

Jan

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Index: src/skins/native/task.c
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
--- src/skins/native/task.c	(Revision 481)
+++ src/skins/native/task.c	(Arbeitskopie)
@@ -59,6 +59,9 @@
     param.sched_priority =3D sched_get_priority_max(SCHED_FIFO);
     pthread_setschedparam(pthread_self(),SCHED_FIFO,&param);
=20
+    /* rt_task_delete requires asynchronous cancellation */
+    pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
+
     signal(SIGCHLD,&rt_task_sigharden);
=20
     bulk.a1 =3D (u_long)iargs->task;
@@ -160,6 +163,9 @@
 {
     struct rt_arg_bulk bulk;
=20
+    /* rt_task_delete requires asynchronous cancellation */
+    pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
+
     signal(SIGCHLD,&rt_task_sigharden);
=20
     bulk.a1 =3D (u_long)task;

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