Fix infinite loop in check_pf (BZ #12926)

The recvmsg could return 0 under some conditions and cause the
make_request function to be stuck in an infinite loop.

Thank you Jim King <jim.king@simplivity.com> for posting Paul's patch
on the list.
conformtest: clean up POSIX expections for sys/utsname.h, sys/wait.h.

Continuing the series of patches to clean up conformtest expectations
for "POSIX" (1995/6) based on review of the expectations against the
standard, this patch cleans up expectations for sys/utsname.h and
sys/wait.h.  Tested x86_64; a new XFAIL for sys/wait.h is added.

	* conform/data/sys/utsname.h-data (*_t): Allow.
	* conform/data/sys/wait.h-data [POSIX] (uid_t): Do not define.
	[POSIX] (WEXITED): Do not expect constant.
	[POSIX] (WSTOPPED): Likewise.
	[POSIX] (WNOHANG): Likewise.
	[POSIX] (WNOWAIT): Likewise.
	[POSIX] (siginfo_t): Do not expect type or elements.
	[POSIX] (pid_t): Do not expect type.
	[POSIX] (signal.h): Do not allow header.
	[POSIX] (sys/resource.h): Likewise.
	[POSIX] (si_*): Do not allow pattern.
	[POSIX] (W*): Likewise.
	[POSIX] (P_*): Likewise.
	[POSIX] (BUS_*): Likewise.
	[POSIX] (CLD_*): Likewise.
	[POSIX] (FPE_*): Likewise.
	[POSIX] (ILL_*): Likewise.
	[POSIX] (POLL_*): Likewise.
	[POSIX] (SEGV_*): Likewise.
	[POSIX] (SI_*): Likewise.
	[POSIX] (TRAP_*): Likewise.
	* conform/Makefile (test-xfail-POSIX/sys/wait.h/conform): New
	variable.
Remove sysdeps/arm/soft-fp directory.
strcoll: improve performance by removing the cache (#15884)

this is a path that should solve bug 15884. It complains about the performance
of strcoll(). It was found out that the runtime of strcoll() is actually bound
to strlen which is needed for calculating the size of a cache that was
installed to improve the comparison performance.

The idea for this patch was that the cache is only useful in rare cases
(strings of same length and same first-level-chars) and that it would be
better to avoid memory allocation at all. To prove this I wrote a performance
test bench-strcoll.c with test data in benchtests-strcoll.tar.gz. Also
modifications in benchtests/Makefile and localedata/Makefile are necessary to
make it work.

After removing the cache the strcoll method showed the predicted behavior
(getting slightly faster) in all but the test case for hindi word sorting.
This was due the hindi text having much more equal words than the other ones.
For equal strings the performance was worse since all comparison levels were
run through and from the second level on the cache improved the comparison
performance of the original version.

Therefore I added a bytewise test via strcmp iff the first level comparison
found that both strings did match because in this case it is very likely that
equal strings are compared. This solved the problem with the hindi test case
and improved the performance of the others.

Performance comparison:

glibc files     -33.77%
vi_VN.UTF-8     -34.12%
en_US.UTF-8     -42.42%
ar_SA.UTF-8     -27.49%
zh_CN.UTF-8     +07.90%
cs_CZ.UTF-8     -29.67%
en_GB.UTF-8     -28.50%
da_DK.UTF-8     -36.57%
pl_PL.UTF-8     -39.31%
fr_FR.UTF-8     -28.57%
pt_PT.UTF-8     -22.82%
el_GR.UTF-8     -26.77%
ru_RU.UTF-8     -35.81%
iw_IL.UTF-8     -35.34%
es_ES.UTF-8     -34.46%
hi_IN.UTF-8     -00.38%
sv_SE.UTF-8     -36.99%
hu_HU.UTF-8     -16.35%
tr_TR.UTF-8     -27.80%
is_IS.UTF-8     -33.24%
it_IT.UTF-8     -24.39%
sr_RS.UTF-8     -37.55%
ja_JP.UTF-8     +02.84%
Fix up incorrect formatting in last commit
Fix NPTL build error when missing __NR_set_robust_list.
NPTL: Conditionalize more uses of SIGCANCEL and SIGSETXID.
NPTL: Conditionalize direct futex syscall uses.
NPTL: Clean up THREAD_SYSINFO macros.
Remove obsolete TLS_DEFINE_INIT_TP fallback.
Move readv and writev definitions to syscalls.list (bug 14138).

Continuing the move of syscall definitions to syscalls.list, where the
removal of support for old kernel versions has made this possible,
this patch moves definitions of readv and writev.

The relevant syscalls.list entries were already in
sysdeps/unix/syscalls.list, but to match the C files they needed to
have the names __libc_readv and __libc_writev added.  In fact, I don't
see anything making use of those names - as far as I can tell, these
functions could just be defined as __readv and __writev with aliases
readv and writev.  But cleaning up unnecessary aliases for functions
should be a separate matter from cleaning up unnecessary C syscall
wrappers.

Tested for x86_64.

	[BZ #14138]
	* sysdeps/unix/syscalls.list (readv): Use __libc_readv as strong
	name.
	(writev): Use __libc_writev as strong name.
	* sysdeps/unix/sysv/linux/readv.c: Remove file.
	* sysdeps/unix/sysv/linux/writev.c: Likewise.
pthread_once: Clean up constants.

[BZ #15215] This just gives a name to the integer constants being used.
pthread_once: Add fast path and remove x86 variants.
Make internal lock-init macros return void.
NPTL: Add some missing #include's
NPTL: Clean up gratuitous Linuxism in libpthread.so entry point.
Tiny refactoring in fts to eliminate a warning.
Avoid local PLT reference in __nptl_main.
Don't use INTDEF with __ldexpf (bug 14132).

Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch removes the use of INTDEF for __ldexpf.  As far as I can tell,
the resulting alias is completely unused.

Tested for x86_64 that stripped installed shared libraries are
unchanged by this patch.

	[BZ #14132]
	* math/s_ldexpf.c (__ldexpf): Do not use INTDEF.
MIPS: Avoid a dangling `vfork@GLIBC_2.0' reference

This satisfies a symbol reference created with:

	.symver	__libc_vfork, vfork@GLIBC_2.0

where `__libc_vfork' has not been defined or referenced.  In this case
the `vfork@GLIBC_2.0' reference is supposed to be discarded, however a
bug present in GAS since forever causes an undefined symbol table entry
to be created.  This in turn triggers a problem in the linker that can
manifest itself by link errors such as:

ld: libpthread.so: invalid string offset 2765592330 >= 5154 for section `.dynstr'

The GAS and linker bugs need to be resolved, but we can avoid them too
by providing a `__libc_vfork' definition just like our other platforms.

	[BZ #17485]
	* sysdeps/unix/sysv/linux/mips/vfork.S (__libc_vfork): Define.