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diff --git a/man3/CPU_SET.3 b/man3/CPU_SET.3 deleted file mode 100644 index 6c13a62..0000000 --- a/man3/CPU_SET.3 +++ /dev/null @@ -1,348 +0,0 @@ -.\" Copyright (C) 2006 Michael Kerrisk -.\" and Copyright (C) 2008 Linux Foundation, written by Michael Kerrisk -.\" <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH CPU_SET 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -CPU_SET, CPU_CLR, CPU_ISSET, CPU_ZERO, CPU_COUNT, -CPU_AND, CPU_OR, CPU_XOR, CPU_EQUAL, -CPU_ALLOC, CPU_ALLOC_SIZE, CPU_FREE, -CPU_SET_S, CPU_CLR_S, CPU_ISSET_S, CPU_ZERO_S, -CPU_COUNT_S, CPU_AND_S, CPU_OR_S, CPU_XOR_S, CPU_EQUAL_S \- -macros for manipulating CPU sets -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */" -.B #include <sched.h> -.P -.BI "void CPU_ZERO(cpu_set_t *" set ); -.P -.BI "void CPU_SET(int " cpu ", cpu_set_t *" set ); -.BI "void CPU_CLR(int " cpu ", cpu_set_t *" set ); -.BI "int CPU_ISSET(int " cpu ", cpu_set_t *" set ); -.P -.BI "int CPU_COUNT(cpu_set_t *" set ); -.P -.BI "void CPU_AND(cpu_set_t *" destset , -.BI " cpu_set_t *" srcset1 ", cpu_set_t *" srcset2 ); -.BI "void CPU_OR(cpu_set_t *" destset , -.BI " cpu_set_t *" srcset1 ", cpu_set_t *" srcset2 ); -.BI "void CPU_XOR(cpu_set_t *" destset , -.BI " cpu_set_t *" srcset1 ", cpu_set_t *" srcset2 ); -.P -.BI "int CPU_EQUAL(cpu_set_t *" set1 ", cpu_set_t *" set2 ); -.P -.BI "cpu_set_t *CPU_ALLOC(int " num_cpus ); -.BI "void CPU_FREE(cpu_set_t *" set ); -.BI "size_t CPU_ALLOC_SIZE(int " num_cpus ); -.P -.BI "void CPU_ZERO_S(size_t " setsize ", cpu_set_t *" set ); -.P -.BI "void CPU_SET_S(int " cpu ", size_t " setsize ", cpu_set_t *" set ); -.BI "void CPU_CLR_S(int " cpu ", size_t " setsize ", cpu_set_t *" set ); -.BI "int CPU_ISSET_S(int " cpu ", size_t " setsize ", cpu_set_t *" set ); -.P -.BI "int CPU_COUNT_S(size_t " setsize ", cpu_set_t *" set ); -.P -.BI "void CPU_AND_S(size_t " setsize ", cpu_set_t *" destset , -.BI " cpu_set_t *" srcset1 ", cpu_set_t *" srcset2 ); -.BI "void CPU_OR_S(size_t " setsize ", cpu_set_t *" destset , -.BI " cpu_set_t *" srcset1 ", cpu_set_t *" srcset2 ); -.BI "void CPU_XOR_S(size_t " setsize ", cpu_set_t *" destset , -.BI " cpu_set_t *" srcset1 ", cpu_set_t *" srcset2 ); -.P -.BI "int CPU_EQUAL_S(size_t " setsize ", cpu_set_t *" set1 \ -", cpu_set_t *" set2 ); -.fi -.SH DESCRIPTION -The -.I cpu_set_t -data structure represents a set of CPUs. -CPU sets are used by -.BR sched_setaffinity (2) -and similar interfaces. -.P -The -.I cpu_set_t -data type is implemented as a bit mask. -However, the data structure should be treated as opaque: -all manipulation of CPU sets should be done via the macros -described in this page. -.P -The following macros are provided to operate on the CPU set -.IR set : -.TP -.BR CPU_ZERO () -Clears -.IR set , -so that it contains no CPUs. -.TP -.BR CPU_SET () -Add CPU -.I cpu -to -.IR set . -.TP -.BR CPU_CLR () -Remove CPU -.I cpu -from -.IR set . -.TP -.BR CPU_ISSET () -Test to see if CPU -.I cpu -is a member of -.IR set . -.TP -.BR CPU_COUNT () -Return the number of CPUs in -.IR set . -.P -Where a -.I cpu -argument is specified, it should not produce side effects, -since the above macros may evaluate the argument more than once. -.P -The first CPU on the system corresponds to a -.I cpu -value of 0, the next CPU corresponds to a -.I cpu -value of 1, and so on. -No assumptions should be made about particular CPUs being -available, or the set of CPUs being contiguous, since CPUs can -be taken offline dynamically or be otherwise absent. -The constant -.B CPU_SETSIZE -(currently 1024) specifies a value one greater than the maximum CPU -number that can be stored in -.IR cpu_set_t . -.P -The following macros perform logical operations on CPU sets: -.TP -.BR CPU_AND () -Store the intersection of the sets -.I srcset1 -and -.I srcset2 -in -.I destset -(which may be one of the source sets). -.TP -.BR CPU_OR () -Store the union of the sets -.I srcset1 -and -.I srcset2 -in -.I destset -(which may be one of the source sets). -.TP -.BR CPU_XOR () -Store the XOR of the sets -.I srcset1 -and -.I srcset2 -in -.I destset -(which may be one of the source sets). -The XOR means the set of CPUs that are in either -.I srcset1 -or -.IR srcset2 , -but not both. -.TP -.BR CPU_EQUAL () -Test whether two CPU set contain exactly the same CPUs. -.SS Dynamically sized CPU sets -Because some applications may require the ability to dynamically -size CPU sets (e.g., to allocate sets larger than that -defined by the standard -.I cpu_set_t -data type), glibc nowadays provides a set of macros to support this. -.P -The following macros are used to allocate and deallocate CPU sets: -.TP -.BR CPU_ALLOC () -Allocate a CPU set large enough to hold CPUs -in the range 0 to -.IR num_cpus\-1 . -.TP -.BR CPU_ALLOC_SIZE () -Return the size in bytes of the CPU set that would be needed to -hold CPUs in the range 0 to -.IR num_cpus\-1 . -This macro provides the value that can be used for the -.I setsize -argument in the -.BR CPU_*_S () -macros described below. -.TP -.BR CPU_FREE () -Free a CPU set previously allocated by -.BR CPU_ALLOC (). -.P -The macros whose names end with "_S" are the analogs of -the similarly named macros without the suffix. -These macros perform the same tasks as their analogs, -but operate on the dynamically allocated CPU set(s) whose size is -.I setsize -bytes. -.SH RETURN VALUE -.BR CPU_ISSET () -and -.BR CPU_ISSET_S () -return nonzero if -.I cpu -is in -.IR set ; -otherwise, it returns 0. -.P -.BR CPU_COUNT () -and -.BR CPU_COUNT_S () -return the number of CPUs in -.IR set . -.P -.BR CPU_EQUAL () -and -.BR CPU_EQUAL_S () -return nonzero if the two CPU sets are equal; otherwise they return 0. -.P -.BR CPU_ALLOC () -returns a pointer on success, or NULL on failure. -(Errors are as for -.BR malloc (3).) -.P -.BR CPU_ALLOC_SIZE () -returns the number of bytes required to store a -CPU set of the specified cardinality. -.P -The other functions do not return a value. -.SH STANDARDS -Linux. -.SH HISTORY -The -.BR CPU_ZERO (), -.BR CPU_SET (), -.BR CPU_CLR (), -and -.BR CPU_ISSET () -macros were added in glibc 2.3.3. -.P -.BR CPU_COUNT () -first appeared in glibc 2.6. -.P -.BR CPU_AND (), -.BR CPU_OR (), -.BR CPU_XOR (), -.BR CPU_EQUAL (), -.BR CPU_ALLOC (), -.BR CPU_ALLOC_SIZE (), -.BR CPU_FREE (), -.BR CPU_ZERO_S (), -.BR CPU_SET_S (), -.BR CPU_CLR_S (), -.BR CPU_ISSET_S (), -.BR CPU_AND_S (), -.BR CPU_OR_S (), -.BR CPU_XOR_S (), -and -.BR CPU_EQUAL_S () -first appeared in glibc 2.7. -.SH NOTES -To duplicate a CPU set, use -.BR memcpy (3). -.P -Since CPU sets are bit masks allocated in units of long words, -the actual number of CPUs in a dynamically -allocated CPU set will be rounded up to the next multiple of -.IR "sizeof(unsigned long)" . -An application should consider the contents of these extra bits -to be undefined. -.P -Notwithstanding the similarity in the names, -note that the constant -.B CPU_SETSIZE -indicates the number of CPUs in the -.I cpu_set_t -data type (thus, it is effectively a count of the bits in the bit mask), -while the -.I setsize -argument of the -.BR CPU_*_S () -macros is a size in bytes. -.P -The data types for arguments and return values shown -in the SYNOPSIS are hints what about is expected in each case. -However, since these interfaces are implemented as macros, -the compiler won't necessarily catch all type errors -if you violate the suggestions. -.SH BUGS -On 32-bit platforms with glibc 2.8 and earlier, -.BR CPU_ALLOC () -allocates twice as much space as is required, and -.BR CPU_ALLOC_SIZE () -returns a value twice as large as it should. -This bug should not affect the semantics of a program, -but does result in wasted memory -and less efficient operation of the macros that -operate on dynamically allocated CPU sets. -These bugs are fixed in glibc 2.9. -.\" http://sourceware.org/bugzilla/show_bug.cgi?id=7029 -.SH EXAMPLES -The following program demonstrates the use of some of the macros -used for dynamically allocated CPU sets. -.P -.\" SRC BEGIN (CPU_SET.c) -.EX -#define _GNU_SOURCE -#include <sched.h> -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -\& -#include <assert.h> -\& -int -main(int argc, char *argv[]) -{ - cpu_set_t *cpusetp; - size_t size, num_cpus; -\& - if (argc < 2) { - fprintf(stderr, "Usage: %s <num\-cpus>\en", argv[0]); - exit(EXIT_FAILURE); - } -\& - num_cpus = atoi(argv[1]); -\& - cpusetp = CPU_ALLOC(num_cpus); - if (cpusetp == NULL) { - perror("CPU_ALLOC"); - exit(EXIT_FAILURE); - } -\& - size = CPU_ALLOC_SIZE(num_cpus); -\& - CPU_ZERO_S(size, cpusetp); - for (size_t cpu = 0; cpu < num_cpus; cpu += 2) - CPU_SET_S(cpu, size, cpusetp); -\& - printf("CPU_COUNT() of set: %d\en", CPU_COUNT_S(size, cpusetp)); -\& - CPU_FREE(cpusetp); - exit(EXIT_SUCCESS); -} -.EE -.\" SRC END -.SH SEE ALSO -.BR sched_setaffinity (2), -.BR pthread_attr_setaffinity_np (3), -.BR pthread_setaffinity_np (3), -.BR cpuset (7) |