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Diffstat (limited to 'man3/pthread_setschedparam.3')
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diff --git a/man3/pthread_setschedparam.3 b/man3/pthread_setschedparam.3 deleted file mode 100644 index 0bc45ccd5..000000000 --- a/man3/pthread_setschedparam.3 +++ /dev/null @@ -1,448 +0,0 @@ -'\" t -.\" Copyright (c) 2008 Linux Foundation, written by Michael Kerrisk -.\" <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH pthread_setschedparam 3 (date) "Linux man-pages (unreleased)" -.SH NAME -pthread_setschedparam, pthread_getschedparam \- set/get -scheduling policy and parameters of a thread -.SH LIBRARY -POSIX threads library -.RI ( libpthread ", " \-lpthread ) -.SH SYNOPSIS -.nf -.B #include <pthread.h> -.P -.BI "int pthread_setschedparam(pthread_t " thread ", int " policy , -.BI " const struct sched_param *" param ); -.BI "int pthread_getschedparam(pthread_t " thread ", int *restrict " policy , -.BI " struct sched_param *restrict " param ); -.fi -.SH DESCRIPTION -The -.BR pthread_setschedparam () -function sets the scheduling policy and parameters of the thread -.IR thread . -.P -.I policy -specifies the new scheduling policy for -.IR thread . -The supported values for -.IR policy , -and their semantics, are described in -.BR sched (7). -.\" FIXME . pthread_setschedparam() places no restriction on the policy, -.\" but pthread_attr_setschedpolicy() restricts policy to RR/FIFO/OTHER -.\" http://sourceware.org/bugzilla/show_bug.cgi?id=7013 -.P -The structure pointed to by -.I param -specifies the new scheduling parameters for -.IR thread . -Scheduling parameters are maintained in the following structure: -.P -.in +4n -.EX -struct sched_param { - int sched_priority; /* Scheduling priority */ -}; -.EE -.in -.P -As can be seen, only one scheduling parameter is supported. -For details of the permitted ranges for scheduling priorities -in each scheduling policy, see -.BR sched (7). -.P -The -.BR pthread_getschedparam () -function returns the scheduling policy and parameters of the thread -.IR thread , -in the buffers pointed to by -.I policy -and -.IR param , -respectively. -The returned priority value is that set by the most recent -.BR pthread_setschedparam (), -.BR pthread_setschedprio (3), -or -.BR pthread_create (3) -call that affected -.IR thread . -The returned priority does not reflect any temporary priority adjustments -as a result of calls to any priority inheritance or -priority ceiling functions (see, for example, -.BR pthread_mutexattr_setprioceiling (3) -and -.BR pthread_mutexattr_setprotocol (3)). -.\" FIXME . nptl/pthread_setschedparam.c has the following -.\" /* If the thread should have higher priority because of some -.\" PTHREAD_PRIO_PROTECT mutexes it holds, adjust the priority. */ -.\" Eventually (perhaps after writing the mutexattr pages), we -.\" may want to add something on the topic to this page. -.SH RETURN VALUE -On success, these functions return 0; -on error, they return a nonzero error number. -If -.BR pthread_setschedparam () -fails, the scheduling policy and parameters of -.I thread -are not changed. -.SH ERRORS -Both of these functions can fail with the following error: -.TP -.B ESRCH -No thread with the ID -.I thread -could be found. -.P -.BR pthread_setschedparam () -may additionally fail with the following errors: -.TP -.B EINVAL -.I policy -is not a recognized policy, or -.I param -does not make sense for the -.IR policy . -.TP -.B EPERM -The caller does not have appropriate privileges -to set the specified scheduling policy and parameters. -.P -POSIX.1 also documents an -.B ENOTSUP -("attempt was made to set the policy or scheduling parameters -to an unsupported value") error for -.BR pthread_setschedparam (). -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR pthread_setschedparam (), -.BR pthread_getschedparam () -T} Thread safety MT-Safe -.TE -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -glibc 2.0 -POSIX.1-2001. -.SH NOTES -For a description of the permissions required to, and the effect of, -changing a thread's scheduling policy and priority, -and details of the permitted ranges for priorities -in each scheduling policy, see -.BR sched (7). -.SH EXAMPLES -The program below demonstrates the use of -.BR pthread_setschedparam () -and -.BR pthread_getschedparam (), -as well as the use of a number of other scheduling-related -pthreads functions. -.P -In the following run, the main thread sets its scheduling policy to -.B SCHED_FIFO -with a priority of 10, -and initializes a thread attributes object with -a scheduling policy attribute of -.B SCHED_RR -and a scheduling priority attribute of 20. -The program then sets (using -.BR pthread_attr_setinheritsched (3)) -the inherit scheduler attribute of the thread attributes object to -.BR PTHREAD_EXPLICIT_SCHED , -meaning that threads created using this attributes object should -take their scheduling attributes from the thread attributes object. -The program then creates a thread using the thread attributes object, -and that thread displays its scheduling policy and priority. -.P -.in +4n -.EX -$ \fBsu\fP # Need privilege to set real\-time scheduling policies -Password: -# \fB./a.out \-mf10 \-ar20 \-i e\fP -Scheduler settings of main thread - policy=SCHED_FIFO, priority=10 -\& -Scheduler settings in \[aq]attr\[aq] - policy=SCHED_RR, priority=20 - inheritsched is EXPLICIT -\& -Scheduler attributes of new thread - policy=SCHED_RR, priority=20 -.EE -.in -.P -In the above output, one can see that the scheduling policy and priority -were taken from the values specified in the thread attributes object. -.P -The next run is the same as the previous, -except that the inherit scheduler attribute is set to -.BR PTHREAD_INHERIT_SCHED , -meaning that threads created using the thread attributes object should -ignore the scheduling attributes specified in the attributes object -and instead take their scheduling attributes from the creating thread. -.P -.in +4n -.EX -# \fB./a.out \-mf10 \-ar20 \-i i\fP -Scheduler settings of main thread - policy=SCHED_FIFO, priority=10 -\& -Scheduler settings in \[aq]attr\[aq] - policy=SCHED_RR, priority=20 - inheritsched is INHERIT -\& -Scheduler attributes of new thread - policy=SCHED_FIFO, priority=10 -.EE -.in -.P -In the above output, one can see that the scheduling policy and priority -were taken from the creating thread, -rather than the thread attributes object. -.P -Note that if we had omitted the -.I \-i\~i -option, the output would have been the same, since -.B PTHREAD_INHERIT_SCHED -is the default for the inherit scheduler attribute. -.SS Program source -\& -.\" SRC BEGIN (pthreads_sched_test.c) -.EX -/* pthreads_sched_test.c */ -\& -#include <errno.h> -#include <pthread.h> -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -\& -#define handle_error_en(en, msg) \e - do { errno = en; perror(msg); exit(EXIT_FAILURE); } while (0) -\& -[[noreturn]] -static void -usage(char *prog_name, char *msg) -{ - if (msg != NULL) - fputs(msg, stderr); -\& - fprintf(stderr, "Usage: %s [options]\en", prog_name); - fprintf(stderr, "Options are:\en"); -#define fpe(msg) fprintf(stderr, "\et%s", msg) /* Shorter */ - fpe("\-a<policy><prio> Set scheduling policy and priority in\en"); - fpe(" thread attributes object\en"); - fpe(" <policy> can be\en"); - fpe(" f SCHED_FIFO\en"); - fpe(" r SCHED_RR\en"); - fpe(" o SCHED_OTHER\en"); - fpe("\-A Use default thread attributes object\en"); - fpe("\-i {e|i} Set inherit scheduler attribute to\en"); - fpe(" \[aq]explicit\[aq] or \[aq]inherit\[aq]\en"); - fpe("\-m<policy><prio> Set scheduling policy and priority on\en"); - fpe(" main thread before pthread_create() call\en"); - exit(EXIT_FAILURE); -} -\& -static int -get_policy(char p, int *policy) -{ - switch (p) { - case \[aq]f\[aq]: *policy = SCHED_FIFO; return 1; - case \[aq]r\[aq]: *policy = SCHED_RR; return 1; - case \[aq]o\[aq]: *policy = SCHED_OTHER; return 1; - default: return 0; - } -} -\& -static void -display_sched_attr(int policy, const struct sched_param *param) -{ - printf(" policy=%s, priority=%d\en", - (policy == SCHED_FIFO) ? "SCHED_FIFO" : - (policy == SCHED_RR) ? "SCHED_RR" : - (policy == SCHED_OTHER) ? "SCHED_OTHER" : - "???", - param\->sched_priority); -} -\& -static void -display_thread_sched_attr(char *msg) -{ - int policy, s; - struct sched_param param; -\& - s = pthread_getschedparam(pthread_self(), &policy, ¶m); - if (s != 0) - handle_error_en(s, "pthread_getschedparam"); -\& - printf("%s\en", msg); - display_sched_attr(policy, ¶m); -} -\& -static void * -thread_start(void *arg) -{ - display_thread_sched_attr("Scheduler attributes of new thread"); -\& - return NULL; -} -\& -int -main(int argc, char *argv[]) -{ - int s, opt, inheritsched, use_null_attrib, policy; - pthread_t thread; - pthread_attr_t attr; - pthread_attr_t *attrp; - char *attr_sched_str, *main_sched_str, *inheritsched_str; - struct sched_param param; -\& - /* Process command\-line options. */ -\& - use_null_attrib = 0; - attr_sched_str = NULL; - main_sched_str = NULL; - inheritsched_str = NULL; -\& - while ((opt = getopt(argc, argv, "a:Ai:m:")) != \-1) { - switch (opt) { - case \[aq]a\[aq]: attr_sched_str = optarg; break; - case \[aq]A\[aq]: use_null_attrib = 1; break; - case \[aq]i\[aq]: inheritsched_str = optarg; break; - case \[aq]m\[aq]: main_sched_str = optarg; break; - default: usage(argv[0], "Unrecognized option\en"); - } - } -\& - if (use_null_attrib - && (inheritsched_str != NULL || attr_sched_str != NULL)) - { - usage(argv[0], "Can\[aq]t specify \-A with \-i or \-a\en"); - } -\& - /* Optionally set scheduling attributes of main thread, - and display the attributes. */ -\& - if (main_sched_str != NULL) { - if (!get_policy(main_sched_str[0], &policy)) - usage(argv[0], "Bad policy for main thread (\-m)\en"); - param.sched_priority = strtol(&main_sched_str[1], NULL, 0); -\& - s = pthread_setschedparam(pthread_self(), policy, ¶m); - if (s != 0) - handle_error_en(s, "pthread_setschedparam"); - } -\& - display_thread_sched_attr("Scheduler settings of main thread"); - printf("\en"); -\& - /* Initialize thread attributes object according to options. */ -\& - attrp = NULL; -\& - if (!use_null_attrib) { - s = pthread_attr_init(&attr); - if (s != 0) - handle_error_en(s, "pthread_attr_init"); - attrp = &attr; - } -\& - if (inheritsched_str != NULL) { - if (inheritsched_str[0] == \[aq]e\[aq]) - inheritsched = PTHREAD_EXPLICIT_SCHED; - else if (inheritsched_str[0] == \[aq]i\[aq]) - inheritsched = PTHREAD_INHERIT_SCHED; - else - usage(argv[0], "Value for \-i must be \[aq]e\[aq] or \[aq]i\[aq]\en"); -\& - s = pthread_attr_setinheritsched(&attr, inheritsched); - if (s != 0) - handle_error_en(s, "pthread_attr_setinheritsched"); - } -\& - if (attr_sched_str != NULL) { - if (!get_policy(attr_sched_str[0], &policy)) - usage(argv[0], "Bad policy for \[aq]attr\[aq] (\-a)\en"); - param.sched_priority = strtol(&attr_sched_str[1], NULL, 0); -\& - s = pthread_attr_setschedpolicy(&attr, policy); - if (s != 0) - handle_error_en(s, "pthread_attr_setschedpolicy"); - s = pthread_attr_setschedparam(&attr, ¶m); - if (s != 0) - handle_error_en(s, "pthread_attr_setschedparam"); - } -\& - /* If we initialized a thread attributes object, display - the scheduling attributes that were set in the object. */ -\& - if (attrp != NULL) { - s = pthread_attr_getschedparam(&attr, ¶m); - if (s != 0) - handle_error_en(s, "pthread_attr_getschedparam"); - s = pthread_attr_getschedpolicy(&attr, &policy); - if (s != 0) - handle_error_en(s, "pthread_attr_getschedpolicy"); -\& - printf("Scheduler settings in \[aq]attr\[aq]\en"); - display_sched_attr(policy, ¶m); -\& - pthread_attr_getinheritsched(&attr, &inheritsched); - printf(" inheritsched is %s\en", - (inheritsched == PTHREAD_INHERIT_SCHED) ? "INHERIT" : - (inheritsched == PTHREAD_EXPLICIT_SCHED) ? "EXPLICIT" : - "???"); - printf("\en"); - } -\& - /* Create a thread that will display its scheduling attributes. */ -\& - s = pthread_create(&thread, attrp, &thread_start, NULL); - if (s != 0) - handle_error_en(s, "pthread_create"); -\& - /* Destroy unneeded thread attributes object. */ -\& - if (!use_null_attrib) { - s = pthread_attr_destroy(&attr); - if (s != 0) - handle_error_en(s, "pthread_attr_destroy"); - } -\& - s = pthread_join(thread, NULL); - if (s != 0) - handle_error_en(s, "pthread_join"); -\& - exit(EXIT_SUCCESS); -} -.EE -.\" SRC END -.SH SEE ALSO -.ad l -.nh -.BR getrlimit (2), -.BR sched_get_priority_min (2), -.BR pthread_attr_init (3), -.BR pthread_attr_setinheritsched (3), -.BR pthread_attr_setschedparam (3), -.BR pthread_attr_setschedpolicy (3), -.BR pthread_create (3), -.BR pthread_self (3), -.BR pthread_setschedprio (3), -.BR pthreads (7), -.BR sched (7) |