From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <439AB897.1020304@domain.hid> Date: Sat, 10 Dec 2005 12:14:31 +0100 From: Paolo Gai MIME-Version: 1.0 Subject: Re: [Xenomai-help] Xenomai 2.0.1 - Posix Skin - realtime priorities - what I'm doing wrong? References: <439995C0.6030006@domain.hid> <200512091650.11637.schwab@domain.hid> <17305.51026.541872.815402@domain.hid> <4399E716.8060502@domain.hid> <17305.63307.340805.330709@domain.hid> <439AB3B6.2080503@domain.hid> In-Reply-To: <439AB3B6.2080503@domain.hid> Content-Type: multipart/mixed; boundary="------------080807060302080408080102" List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Gai Cc: xenomai@xenomai.org This is a multi-part message in MIME format. --------------080807060302080408080102 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Ok, after having clicked ion the send button, I also discovered that=20 NPTL uses INHERIT_SCHED by default in the pthread attributes http://sources.redhat.com/bugzilla/show_bug.cgi?id=3D145 I added it to the original examples, and I obtained the following=20 (basically it is similar to the Case 1 depicted before...) Linux Real-Time Threads [root@domain.hid xenomai-demos]# ./ex_rr LOW priority thread!!! =2E..........###########............############...........###########...= =2E.......###########............############...........###########......= =2E.....############...........###########...........###########.........= =2E..############...........###########...........###########............= ############...........###########...........###########............#####= #######...........###########............############...........#########= ##...........###########............############...........###########...= =2E.......###########............############...........###########......= =2E....###########.....#####LOW=20 priority thread!!! =2E......................................................................= =2E......................................................................= =2E......................................................................= =2E......................................................................= =2E...............#######################################################= #########################################################################= #########################################################################= #########################################################################= ##########################[root@domain.hid xenomai-demos]# --> that's fine; Xenomai Threads: [root@domain.hid xenomai-demos]# ./rt_ex_rr LOW priority thread!!! =2E....###...............................................................= =2E................######################################################= #########################................................................= =2E..............................########################################= ########################################.................................= =2E..............................................########################= #######################################################..................= =2E.....................................#################################= ##########################...............................................= =2E......................................................................= =2E......................................................................= =2E......................................................................= =2E.......................................LOW=20 priority thread!!! #########################################################################= #########################################################################= #########################################################################= #########################################################################= ########[root@domain.hid xenomai-demos]# That is not what should be :-( Again, in this case there may be an additional influence of using the=20 stdio with mutexes and so on... bye Paolo --------------080807060302080408080102 Content-Type: text/x-csrc; name="ex_rr.c" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="ex_rr.c" /* * Linux FIFO/RR scheduler demo * * This demo creates a few tasks scheduled with the SCHED_FIFO or the * SCHED_RR scheduler * * Copyright (C) 2002 by Paolo Gai * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include /* for sched_param.c */ #include void *low(void *arg) { printf("LOW priority thread!!!\n"); return NULL; } void *medium(void *arg) { int i,j; for (i=0; i<300; i++) { for (j=0; j<1000000; j++) ; printf((char *)arg); } return NULL; } void my_create(int policy) { pthread_t th1, th2, th3; pthread_attr_t medium_attr, low_attr; struct sched_param medium_policy, low_policy; pthread_attr_init(&medium_attr); pthread_attr_setinheritsched(&medium_attr, PTHREAD_EXPLICIT_SCHED); pthread_attr_setschedpolicy(&medium_attr, policy); medium_policy.sched_priority = 2; pthread_attr_setschedparam(&medium_attr, &medium_policy); pthread_attr_init(&low_attr); pthread_attr_setinheritsched(&medium_attr, PTHREAD_EXPLICIT_SCHED); pthread_attr_setschedpolicy(&low_attr, SCHED_FIFO); low_policy.sched_priority = 1; pthread_attr_setschedparam(&low_attr, &low_policy); pthread_create(&th1, &medium_attr, medium, (char *)"."); pthread_create(&th2, &medium_attr, medium, (char *)"#"); pthread_create(&th3, &low_attr, low, NULL); pthread_attr_destroy(&medium_attr); pthread_attr_destroy(&low_attr); pthread_join(th1, NULL); pthread_join(th2, NULL); pthread_join(th3, NULL); } void *high(void *arg) { /* first experiment: - two medium priority thread scheduled with RR - one low priority thread scheduled with FIFO */ my_create(SCHED_RR); /* second experiment: - two medium priority thread scheduled with FIFO - one low priority thread scheduled with FIFO */ my_create(SCHED_FIFO); return NULL; } int main() { pthread_t mythread; pthread_attr_t myattr; struct sched_param myparam; int err; int parameter; void *returnvalue; /* initializes the thread attribute */ pthread_attr_init(&myattr); pthread_attr_setinheritsched(&myattr, PTHREAD_EXPLICIT_SCHED); pthread_attr_setschedpolicy(&myattr, SCHED_FIFO); myparam.sched_priority = 3; pthread_attr_setschedparam(&myattr, &myparam); err = pthread_create(&mythread, &myattr, high, (void *)¶meter); if (err) { perror("ERROR"); exit(1); } pthread_attr_destroy(&myattr); /* wait the end of the thread we just created */ pthread_join(mythread, &returnvalue); return 0; } --------------080807060302080408080102--