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Florian Weimer 2359035ac5 Remove CPU set size checking from affinity functions [BZ #19143]
With current kernel versions, the check does not reliably detect that
unavailable CPUs are requested, for these reasons:

(1) The kernel will silently ignore non-allowed CPUs, that is, CPUs
    which are physically present but disallowed for the thread
    based on system configuration.

(2) Similarly, CPU bits which lack an online CPU (possible CPUs)
    are ignored.

(3) The existing probing code assumes that the CPU mask size is a
    power of two and at least 1024.  Neither has it to be a power
    of two, nor is the minimum possible value 1024, so the value
    determined is often too large.  This means that the CPU set
    size check in glibc accepts CPU bits beyond the actual hard
    system limit.

(4) Future kernel versions may not even have a fixed CPU set size.

After the removal of the probing code, the kernel still returns
EINVAL if no CPU in the requested set remains which can run the
thread after the affinity change.

Applications which care about the exact affinity mask will have
to query it using sched_getaffinity after setting it.  Due to the
effects described above, this commit does not change this.

The new tests supersede tst-getcpu, which is removed.  This
addresses bug 19164 because the new tests allocate CPU sets
dynamically.

	* nptl/check-cpuset.h: Remove.
	* nptl/pthread_attr_setaffinity.c (__pthread_attr_setaffinity_new):
	Remove CPU set size check.
	* nptl/pthread_setattr_default_np.c (pthread_setattr_default_np):
	Likewise.
	* sysdeps/unix/sysv/linux/check-cpuset.h: Remove.
	* sysdeps/unix/sysv/linux/pthread_setaffinity.c
	(__kernel_cpumask_size, __determine_cpumask_size): Remove.
	(__pthread_setaffinity_new): Remove CPU set size check.
	* sysdeps/unix/sysv/linux/sched_setaffinity.c
	(__kernel_cpumask_size): Remove.
	(__sched_setaffinity_new): Remove CPU set size check.
	* manual/threads.texi (Default Thread Attributes): Remove stale
	reference to check_cpuset_attr, determine_cpumask_size in comment.
	* sysdeps/unix/sysv/linux/Makefile [$(subdir) == posix] (tests):
	Remove tst-getcpu.  Add tst-affinity, tst-affinity-pid.
	[$(subdir) == nptl] (tests): Add tst-thread-affinity-pthread,
	tst-thread-affinity-pthread2, tst-thread-affinity-sched.
	* sysdeps/unix/sysv/linux/tst-affinity.c: New file.
	* sysdeps/unix/sysv/linux/tst-affinity-pid.c: New file.
	* sysdeps/unix/sysv/linux/tst-skeleton-affinity.c: New skeleton test file.
	* sysdeps/unix/sysv/linux/tst-thread-affinity-sched.c: New file.
	* sysdeps/unix/sysv/linux/tst-thread-affinity-pthread.c: New file.
	* sysdeps/unix/sysv/linux/tst-thread-affinity-pthread2.c: New file.
	* sysdeps/unix/sysv/linux/tst-thread-skeleton-affinity.c: New
	skeleton test file.
	* sysdeps/unix/sysv/linux/tst-getcpu.c: Remove.  Superseded by
	tst-affinity-pid.
2015-11-24 17:21:01 +01:00
argp
assert Don't macro-expand failed assertion expression [BZ #18604] 2015-11-03 23:26:15 +01:00
benchtests benchtests: Mark output variables as used 2015-11-17 16:01:15 +05:30
bits Move bits/atomic.h to atomic-machine.h (bug 14912). 2015-09-11 20:00:19 +00:00
catgets
conf
conform Fix lgamma setting signgam for ISO C (bug 15421). 2015-11-20 22:49:59 +00:00
crypt Convert 113 more function definitions to prototype style (files with assertions). 2015-10-20 11:54:09 +00:00
csu
ctype Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
debug tst-backtrace4: fix a warning message 2015-10-21 11:24:27 -04:00
dirent Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
dlfcn
elf Implement "make update-all-abi" 2015-11-24 17:10:19 +01:00
gmon Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
gnulib
grp Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
gshadow Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
hesiod
hurd Convert 113 more function definitions to prototype style (files with assertions). 2015-10-20 11:54:09 +00:00
iconv Fix BZ #19012 -- iconv_open leaks memory on error path. 2015-10-05 20:03:48 -07:00
iconvdata Add dependencies on needed locales in each subdir tests (bug 18969) 2015-10-12 15:18:08 +02:00
include Fix lgamma setting signgam for ISO C (bug 15421). 2015-11-20 22:49:59 +00:00
inet Convert 113 more function definitions to prototype style (files with assertions). 2015-10-20 11:54:09 +00:00
intl Add dependencies on needed locales in each subdir tests (bug 18969) 2015-10-12 15:18:08 +02:00
io Add LFS support for fts functions (bug 11460) 2015-11-06 11:24:16 +01:00
libidn
libio Convert miscellaneous function definitions to prototype style. 2015-10-20 21:27:22 +00:00
locale Gracefully handle incompatible locale data 2015-10-27 13:33:26 +01:00
localedata lt_LT: change currency symbol to the euro [BZ #18953] 2015-10-17 00:28:13 -04:00
login Convert miscellaneous function definitions to prototype style. 2015-10-20 21:27:22 +00:00
mach Convert miscellaneous function definitions to prototype style. 2015-10-20 21:27:22 +00:00
malloc Replace MUTEX_INITIALIZER with _LIBC_LOCK_INITIALIZER in generic code 2015-11-24 16:37:15 +01:00
manual Remove CPU set size checking from affinity functions [BZ #19143] 2015-11-24 17:21:01 +01:00
math Fix lgamma setting signgam for ISO C (bug 15421). 2015-11-20 22:49:59 +00:00
mathvec
misc Fix some stub prototypes missing ... after K&R conversion 2015-11-05 15:00:12 -08:00
nis Assume that SOCK_CLOEXEC is available and works 2015-10-17 12:02:37 +02:00
nptl Remove CPU set size checking from affinity functions [BZ #19143] 2015-11-24 17:21:01 +01:00
nptl_db Convert 113 more function definitions to prototype style (files with assertions). 2015-10-20 11:54:09 +00:00
nscd use -fstack-protector-strong when available 2015-10-19 15:36:48 -04:00
nss Convert 113 more function definitions to prototype style (files with assertions). 2015-10-20 11:54:09 +00:00
po Update de.po from Translation Project (bug 4404). 2015-09-16 16:51:28 +00:00
posix Convert a few more function definitions to prototype style. 2015-10-21 11:57:23 +00:00
pwd Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
resolv Remove GCC version conditionals on -Wmaybe-uninitialized pragmas. 2015-10-27 23:42:20 +00:00
resource Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
rt Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
scripts Implement "make update-all-abi" 2015-11-24 17:10:19 +01:00
setjmp
shadow Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
signal Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
socket Convert 24 more function definitions to prototype style (array parameters). 2015-10-20 11:51:03 +00:00
soft-fp Remove GCC version conditionals on -Wmaybe-uninitialized pragmas. 2015-10-27 23:42:20 +00:00
stdio-common Convert 69 more function definitions to prototype style (line wrap cases). 2015-10-19 21:23:47 +00:00
stdlib Fix strtol in Turkish locales (bug 19242). 2015-11-23 08:50:53 +00:00
streams Convert 69 more function definitions to prototype style (line wrap cases). 2015-10-19 21:23:47 +00:00
string Convert miscellaneous function definitions to prototype style. 2015-10-20 21:27:22 +00:00
sunrpc Convert a few more function definitions to prototype style. 2015-10-21 11:57:23 +00:00
sysdeps Remove CPU set size checking from affinity functions [BZ #19143] 2015-11-24 17:21:01 +01:00
sysvipc Convert 69 more function definitions to prototype style (line wrap cases). 2015-10-19 21:23:47 +00:00
termios Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
time Convert miscellaneous function definitions to prototype style. 2015-10-20 21:27:22 +00:00
timezone Update timezone/Makefile to use -Wno-unused-variable 2015-10-07 15:04:49 -07:00
wcsmbs Fix strtol in Turkish locales (bug 19242). 2015-11-23 08:50:53 +00:00
wctype Convert 703 function definitions to prototype style. 2015-10-16 20:21:49 +00:00
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BUGS
ChangeLog Remove CPU set size checking from affinity functions [BZ #19143] 2015-11-24 17:21:01 +01:00
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config.h.in Remove -mavx2 configure tests. 2015-10-28 13:29:03 +00:00
config.make.in Run tst-prelink test for GLOB_DAT reloc 2015-11-14 12:00:38 -08:00
configure Run tst-prelink test for GLOB_DAT reloc 2015-11-14 12:00:38 -08:00
configure.ac Run tst-prelink test for GLOB_DAT reloc 2015-11-14 12:00:38 -08:00
CONFORMANCE
COPYING
COPYING.LIB
cppflags-iterator.mk
extra-lib.mk
extra-modules.mk
gen-locales.mk
INSTALL Require GCC 4.7 or later to build glibc. 2015-10-27 16:34:12 +00:00
libc-abis
LICENSES
Makeconfig Use -std=gnu11 instead of -std=gnu99. 2015-10-27 21:47:22 +00:00
Makefile Implement "make update-all-abi" 2015-11-24 17:10:19 +01:00
Makefile.in
Makerules Implement "make update-all-abi" 2015-11-24 17:10:19 +01:00
NAMESPACE
NEWS Remove CPU set size checking from affinity functions [BZ #19143] 2015-11-24 17:21:01 +01:00
o-iterator.mk
PROJECTS
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