rpms/man-pages/devel man-pages-3.22-sched_setaffinity.patch, NONE, 1.1 man-pages.spec, 1.124, 1.125

[Ivana Varekova]

Author: varekova

Update of /cvs/pkgs/rpms/man-pages/devel
In directory cvs1.fedora.phx.redhat.com:/tmp/cvs-serv21813

Modified Files:
	man-pages.spec 
Added Files:
	man-pages-3.22-sched_setaffinity.patch 
Log Message:
- fix sched_setaffinity(2) page - add an EXAMPLE and new NOTES


man-pages-3.22-sched_setaffinity.patch:
 sched_setaffinity.2 |   54 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

--- NEW FILE man-pages-3.22-sched_setaffinity.patch ---
diff -up man-pages-3.22/man2/sched_setaffinity.2.orig man-pages-3.22/man2/sched_setaffinity.2
--- man-pages-3.22/man2/sched_setaffinity.2.orig	2009-07-25 08:53:26.000000000 +0200
+++ man-pages-3.22/man2/sched_setaffinity.2	2009-12-02 15:29:17.000000000 +0100
@@ -212,6 +212,60 @@ system call returns the size (in bytes) 
 .I cpumask_t
 data type that is used internally by the kernel to
 represent the CPU set bit mask.
+
+The \fBcpu_set_t\fR affinity mask size provided by glibc only allows for upto
+1024 CPUs. It is possible to build Linux kernels with greater than 1024
+CPUs. Any application using the statically sized \fBcpu_set_t\fR will fail
+with \fBEINVAL\fR on such kernels. It is thus recommended that applications
+avoid using the statically sized \fBcpu_set_t\fR type, and instead dynamically
+allocate a mask using the CPU_*_S macros described in the \fBCPU_SET(3)\fR man
+page. Since it is not possible to determine ahead of time what \fBNR_CPUS\fR
+value the kernel was built with, applications must be prepared to catch
+\fBEINVAL\fR, and retry the command with a larger dynamically allocated mask.
+The example that follows illustrates portable usage.
+
+.SH EXAMPLE
+.nf
+   #define _GNU_SOURCE
+
+   #include <sched.h>
+   #include <stdio.h>
+   #include <errno.h>
+
+   int main(void)
+   {
+        cpu_set_t *mask;
+        size_t size;
+        int i;
+        int nrcpus = 1024;
+
+realloc:
+        mask = CPU_ALLOC(nrcpus);
+        size = CPU_ALLOC_SIZE(nrcpus);
+        CPU_ZERO_S(size, mask);
+        if ( sched_getaffinity(0, size, mask) == -1 ) {
+                CPU_FREE(mask);
+                if (errno == EINVAL &&
+                    nrcpus < (1024 << 8)) {
+                       nrcpus = nrcpus << 2;
+                       goto realloc;
+                }
+                perror("sched_getaffinity");
+                return -1;
+        }
+
+        for ( i = 0; i < nrcpus; i++ ) {
+                if ( CPU_ISSET_S(i, size, mask) ) {
+                        printf("CPU %d is set\n", (i+1));
+                }
+        }
+
+        CPU_FREE(mask);
+
+        return 0;
+   }  
+.fi
+
 .SH "SEE ALSO"
 .BR clone (2),
 .BR getcpu (2),


Index: man-pages.spec
===================================================================
RCS file: /cvs/pkgs/rpms/man-pages/devel/man-pages.spec,v
retrieving revision 1.124
retrieving revision 1.125
diff -u -p -r1.124 -r1.125
--- man-pages.spec	18 Nov 2009 12:25:03 -0000	1.124
+++ man-pages.spec	2 Dec 2009 14:42:05 -0000	1.125
@@ -4,7 +4,7 @@
 Summary: Man (manual) pages from the Linux Documentation Project
 Name: man-pages
 Version: 3.23
-Release: 2%{?dist}
+Release: 3%{?dist}
 License: GPLv2+ and GPL+ and BSD and MIT and Copyright only and IEEE
 Group: Documentation
 URL: http://www.kernel.org/pub/linux/docs/manpages/
@@ -33,6 +33,7 @@ Patch56: man-pages-3.22-strcpy.patch
 Patch57: man-pages-3.22-nsswitch.conf.patch
 Patch58: man-pages-3.23-proc.patch
 Patch59: man-pages-3.23-ld.so.patch
+Patch60: man-pages-3.22-sched_setaffinity.patch
 
 Buildroot: %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 Autoreq: false
@@ -64,6 +65,7 @@ rmdir man-pages-posix-%{posix_version}-%
 %patch57 -p1
 %patch58 -p1
 %patch59 -p1
+%patch60 -p1
 
 ### And now remove those we are not going to use:
 
@@ -134,6 +136,9 @@ rm -rf $RPM_BUILD_ROOT
 %lang(en) %{_mandir}/en/man*
 
 %changelog
+* Wed Dec  2 2009 Ivana Hutarova Varekova <varekova at redhat.com> - 3.22-7
+- fix sched_setaffinity(2) page - add an EXAMPLE and new NOTES
+
 * Wed Nov 18 2009 Ivana Varekova <varekova at redhat.com> - 3.23-2
 - fix ld.so man-page (#532629)