Commit Graph

126 Commits

Author SHA1 Message Date
Adhemerval Zanella
0377a7fde6 nptl: Remove rwlock elision definitions
The new rwlock implementation added by cc25c8b4c1 (2.25) removed
support for lock-elision.  This patch removes remaining the
arch-specific unused definitions.

Checked with a build against all affected ABIs.

Change-Id: I5dec8af50e3cd56d7351c52ceff4aa3771b53cd6
2019-11-26 13:53:36 +00:00
Mike Crowe
3ef5e118f2 nptl: Fix niggles with pthread_clockjoin_np
Joseph Myers spotted[1] that 69ca4b54c1 added
pthread_clockjoin_np to sysdeps/nptl/pthread.h but not to its hppa-specific
equivalent sysdeps/unix/sysv/linux/hppa/pthread.h.

Rafal Luzynski spotted[2] typos in the NEWS entry and manual updates too.

Florian Weimer spotted[3] that the clockid parameter was not using a
reserved identifier in pthread.h.

[1] https://sourceware.org/ml/libc-alpha/2019-11/msg00016.html
[2] https://sourceware.org/ml/libc-alpha/2019-11/msg00019.html
[3] https://sourceware.org/ml/libc-alpha/2019-11/msg00022.html

Reviewed-by: Joseph Myers <joseph@codesourcery.com>
Reviewed-by: Rafal Luzynski <digitalfreak@lingonborough.com>
Reviewed-by: Florian Weimer <fw@deneb.enyo.de>
2019-11-04 16:44:49 -03:00
Mike Crowe
69ca4b54c1 nptl: Add pthread_clockjoin_np
Introduce pthread_clockjoin_np as a version of pthread_timedjoin_np that
accepts a clockid_t parameter to indicate which clock the timeout should be
measured against. This mirrors the recently-added POSIX-proposed "clock"
wait functions.

Checked on x86_64-linux-gnu.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-11-01 11:23:43 -03:00
Adhemerval Zanella
6b1472eb2e Refactor PI mutexes internal definitions
This patch adds the generic futex_lock_pi and futex_unlock_pi to wrap
around the syscall machinery required to issue the syscall calls. It
simplifies a bit the futex code required to implement PI mutexes.

No function changes, checked on x86_64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2019-10-31 11:09:10 -03:00
Adhemerval Zanella
215078017f nptl: Replace non cancellable pause/nanosleep with futex
To help y2038 work avoid duplicate all the logic of nanosleep on
non cancellable version, the patch replace it with a new futex
operation, lll_timedwait.  The changes are:

  - Add a expected value for __lll_clocklock_wait, so it can be used
    to wait for generic values.

  - Remove its internal atomic operation and move the logic to
    __lll_clocklock.  It makes __lll_clocklock_wait even more generic
    and __lll_clocklock slight faster on fast-path (since it won't
    require a function call anymore).

  - Add lll_timedwait, which uses __lll_clocklock_wait, to replace both
    __pause_nocancel and __nanosleep_nocancel.

It also allows remove the sparc32 __lll_clocklock_wait implementation
(since it is similar to the generic one).

Checked on x86_64-linux-gnu, sparcv9-linux-gnu, and i686-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2019-10-31 11:09:01 -03:00
Adhemerval Zanella
b580327434 Consolidate lowlevellock-futex.h
NPTL is already Linux specific, there is no need to parametrize low
level lock futex operations and add a sysdep Linux specific
implementation.  This patch moves the relevant Linux code to nptl one.

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2019-10-31 11:08:57 -03:00
Adhemerval Zanella
b865eed0ac Consolidate futex-internal.h
NPTL is already Linux specific, there is no need to parametrize futex
operations and add a sysdep Linux specific implementation.  This patch
moves the relevant Linux code to nptl one.

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2019-10-31 11:08:54 -03:00
Florian Weimer
e4b3707cea nptl: SIGCANCEL, SIGTIMER, SIGSETXID are always defined
All nptl targets have these signal definitions nowadays.  This
changes also replaces the nptl-generic version of pthread_sigmask
with the Linux version.

Tested on x86_64-linux-gnu and i686-linux-gnu.  Built with
build-many-glibcs.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2019-10-18 14:29:04 +02:00
Florian Weimer
ca602c1536 nptl: Move pthread_attr_setschedparam implementation into libc
This is part of the libpthread removal project:

  <https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-10-07 20:00:38 +02:00
Florian Weimer
0caab6638e nptl: Move pthread_attr_getschedparam implementation into libc
This is part of the libpthread removal project:

  <https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-10-07 15:49:48 +02:00
Florian Weimer
eaad14b56a nptl: Move pthread_attr_setinheritsched implementation into libc.
This is part of the libpthread removal project:

  <https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
2019-10-04 17:38:06 +02:00
Alistair Francis
aa706e13f4 Split up endian.h to minimize exposure of BYTE_ORDER.
With only two exceptions (sys/types.h and sys/param.h, both of which
historically might have defined BYTE_ORDER) the public headers that
include <endian.h> only want to be able to test __BYTE_ORDER against
__*_ENDIAN.

This patch creates a new bits/endian.h that can be included by any
header that wants to be able to test __BYTE_ORDER and/or
__FLOAT_WORD_ORDER against the __*_ENDIAN constants, or needs
__LONG_LONG_PAIR.  It only defines macros in the implementation
namespace.

The existing bits/endian.h (which could not be included independently
of endian.h, and only defines __BYTE_ORDER and maybe __FLOAT_WORD_ORDER)
is renamed to bits/endianness.h.  I also took the opportunity to
canonicalize the form of this header, which we are stuck with having
one copy of per architecture.  Since they are so short, this means git
doesn’t understand that they were renamed from existing headers, sigh.

endian.h itself is a nonstandard header and its only remaining use
from a standard header is guarded by __USE_MISC, so I dropped the
__USE_MISC conditionals from around all of the public-namespace things
it defines.  (This means, an application that requests strict library
conformance but includes endian.h will still see the definition of
BYTE_ORDER.)

A few changes to specific bits/endian(ness).h variants deserve
mention:

 - sysdeps/unix/sysv/linux/ia64/bits/endian.h is moved to
   sysdeps/ia64/bits/endianness.h.  If I remember correctly, ia64 did
   have selectable endianness, but we have assembly code in
   sysdeps/ia64 that assumes it’s little-endian, so there is no reason
   to treat the ia64 endianness.h as linux-specific.

 - The C-SKY port does not fully support big-endian mode, the compile
   will error out if __CSKYBE__ is defined.

 - The PowerPC port had extra logic in its bits/endian.h to detect a
   broken compiler, which strikes me as unnecessary, so I removed it.

 - The only files that defined __FLOAT_WORD_ORDER always defined it to
   the same value as __BYTE_ORDER, so I removed those definitions.
   The SH bits/endian(ness).h had comments inconsistent with the
   actual setting of __FLOAT_WORD_ORDER, which I also removed.

 - I *removed* copyright boilerplate from the few bits/endian(ness).h
   headers that had it; these files record a single fact in a fashion
   dictated by an external spec, so I do not think they are copyrightable.

As long as I was changing every copy of ieee754.h in the tree, I
noticed that only the MIPS variant includes float.h, because it uses
LDBL_MANT_DIG to decide among three different versions of
ieee854_long_double.  This patch makes it not include float.h when
GCC’s intrinsic __LDBL_MANT_DIG__ is available.

	* string/endian.h: Unconditionally define LITTLE_ENDIAN,
	BIG_ENDIAN, PDP_ENDIAN, and BYTE_ORDER.	 Condition byteswapping
	macros only on !__ASSEMBLER__.	Move the definitions of
	__BIG_ENDIAN, __LITTLE_ENDIAN, __PDP_ENDIAN, __FLOAT_WORD_ORDER,
	and __LONG_LONG_PAIR to...
	* string/bits/endian.h: ...this new file, which includes
	the renamed header bits/endianness.h for the definition of
	__BYTE_ORDER and possibly __FLOAT_WORD_ORDER.

	* string/Makefile: Install bits/endianness.h.
	* include/bits/endian.h: New wrapper.

	* bits/endian.h: Rename to bits/endianness.h.
	Add multiple-include guard.  Rewrite the comment explaining what
	the machine-specific variants of this file should do.

	* sysdeps/unix/sysv/linux/ia64/bits/endian.h:
	Move to sysdeps/ia64.

	* sysdeps/aarch64/bits/endian.h
	* sysdeps/alpha/bits/endian.h
	* sysdeps/arm/bits/endian.h
	* sysdeps/csky/bits/endian.h
	* sysdeps/hppa/bits/endian.h
	* sysdeps/ia64/bits/endian.h
	* sysdeps/m68k/bits/endian.h
	* sysdeps/microblaze/bits/endian.h
	* sysdeps/mips/bits/endian.h
	* sysdeps/nios2/bits/endian.h
	* sysdeps/powerpc/bits/endian.h
	* sysdeps/riscv/bits/endian.h
	* sysdeps/s390/bits/endian.h
	* sysdeps/sh/bits/endian.h
	* sysdeps/sparc/bits/endian.h
	* sysdeps/x86/bits/endian.h:
	Rename to endianness.h; canonicalize form of file; remove
	redundant definitions of __FLOAT_WORD_ORDER.

	* sysdeps/powerpc/bits/endianness.h: Remove logic to check for
	broken compilers.

	* ctype/ctype.h
	* sysdeps/aarch64/nptl/bits/pthreadtypes-arch.h
	* sysdeps/arm/nptl/bits/pthreadtypes-arch.h
	* sysdeps/csky/nptl/bits/pthreadtypes-arch.h
	* sysdeps/ia64/ieee754.h
	* sysdeps/ieee754/ieee754.h
	* sysdeps/ieee754/ldbl-128/ieee754.h
	* sysdeps/ieee754/ldbl-128ibm/ieee754.h
	* sysdeps/m68k/nptl/bits/pthreadtypes-arch.h
	* sysdeps/microblaze/nptl/bits/pthreadtypes-arch.h
	* sysdeps/mips/ieee754/ieee754.h
	* sysdeps/mips/nptl/bits/pthreadtypes-arch.h
	* sysdeps/nios2/nptl/bits/pthreadtypes-arch.h
	* sysdeps/nptl/pthread.h
	* sysdeps/riscv/nptl/bits/pthreadtypes-arch.h
	* sysdeps/sh/nptl/bits/pthreadtypes-arch.h
	* sysdeps/sparc/sparc32/ieee754.h
	* sysdeps/unix/sysv/linux/generic/bits/stat.h
	* sysdeps/unix/sysv/linux/generic/bits/statfs.h
	* sysdeps/unix/sysv/linux/sys/acct.h
	* wctype/bits/wctype-wchar.h:
	Include bits/endian.h, not endian.h.

	* sysdeps/unix/sysv/linux/hppa/pthread.h: Don’t include endian.h.

	* sysdeps/mips/ieee754/ieee754.h: Use __LDBL_MANT_DIG__
	in ifdefs, instead of LDBL_MANT_DIG.  Only include float.h
	when __LDBL_MANT_DIG__ is not predefined, in which case
	define __LDBL_MANT_DIG__ to equal LDBL_MANT_DIG.
2019-10-01 14:54:46 -07:00
Paul Eggert
5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:

sed -ri '
  s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
  s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
  $(find $(git ls-files) -prune -type f \
      ! -name '*.po' \
      ! -name 'ChangeLog*' \
      ! -path COPYING ! -path COPYING.LIB \
      ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
      ! -path manual/texinfo.tex ! -path scripts/config.guess \
      ! -path scripts/config.sub ! -path scripts/install-sh \
      ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
      ! -path INSTALL ! -path  locale/programs/charmap-kw.h \
      ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
      ! '(' -name configure \
            -execdir test -f configure.ac -o -f configure.in ';' ')' \
      ! '(' -name preconfigure \
            -execdir test -f preconfigure.ac ';' ')' \
      -print)

and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:

  chmod a+x sysdeps/unix/sysv/linux/riscv/configure
  # Omit irrelevant whitespace and comment-only changes,
  # perhaps from a slightly-different Autoconf version.
  git checkout -f \
    sysdeps/csky/configure \
    sysdeps/hppa/configure \
    sysdeps/riscv/configure \
    sysdeps/unix/sysv/linux/csky/configure
  # Omit changes that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
  git checkout -f \
    sysdeps/powerpc/powerpc64/ppc-mcount.S \
    sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
  # Omit change that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
  git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 02:43:31 -07:00
Florian Weimer
9743c6272d nptl: Move pthread_attr_getinheritsched implementation into libc
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-30 07:33:02 +02:00
Florian Weimer
ffced383cd nptl: Move pthread_attr_setdetachstate implementation into libc
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-28 12:01:14 +02:00
Florian Weimer
1d714fd95d nptl: Move pthread_attr_getdetachstate implementation into libc
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-16 22:44:44 +02:00
Florian Weimer
a635d756ff nptl: Move pthread_attr_init implementation into libc
Both the original GLIB_2.0 version and the current GLIBC_2.1 version
need to be moved.
2019-08-15 19:12:21 +02:00
Florian Weimer
fa57c30193 nptl: Move pthread_attr_destroy implementation into libc 2019-08-15 13:06:50 +02:00
Florian Weimer
dda373b00e nptl: Move pthread_equal implementation into libc 2019-08-15 08:48:31 +02:00
Mike Crowe
4a8f6d3155 nptl: Remove unnecessary forwarding of pthread_cond_clockwait from libc
In afe4de7d28, I added forwarding functions
from libc to libpthread for __pthread_cond_clockwait and
pthread_cond_clockwait to mirror those for pthread_cond_timedwait. These
are unnecessary[1], since these functions aren't (yet) being called from
within libc itself. Let's remove them.

      * nptl/forward.c: Remove unnecessary __pthread_cond_clockwait and
	pthread_cond_clockwait forwarding functions.  There are no internal
	users, so it is unnecessary to expose these functions in libc.so.
	* sysdeps/nptl/pthread-functions.h (pthread_functions): Remove
	unnecessary ptr___pthread_cond_clockwait member.
	* nptl/nptl-init.c (pthread_functions): Remove assignment of
	removed member.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

[1] https://sourceware.org/ml/libc-alpha/2017-10/msg00082.html
2019-07-18 11:24:33 -03:00
Mike Crowe
1ff1373b33 nptl: Remove futex_supports_exact_relative_timeouts
The only implementation of futex_supports_exact_relative_timeouts always
returns true. Let's remove it and all its callers.

	* nptl/pthread_cond_wait.c: (__pthread_cond_clockwait): Remove code
	that is only useful if futex_supports_exact_relative_timeouts ()
	returns false.
	* nptl/pthread_condattr_setclock.c: (pthread_condattr_setclock):
	Likewise.
	* sysdeps/nptl/futex-internal.h: Remove comment about relative
	timeouts potentially being imprecise since it's no longer true.
	Remove declaration of futex_supports_exact_relative_timeouts.
	* sysdeps/unix/sysv/linux/futex-internal.h: Remove implementation
	of futex_supports_exact_relative_timeouts.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12 13:36:25 +00:00
Mike Crowe
9d20e22e46 nptl: Add POSIX-proposed pthread_mutex_clocklock
Add POSIX-proposed pthread_mutex_clocklock function that works like
pthread_mutex_timedlock but takes a clockid parameter to measure the
abstime parameter against.

	* sysdeps/nptl/pthread.h: Add pthread_mutex_clocklock.
	* nptl/DESIGN-systemtap-probes.txt: Likewise.
	* nptl/pthread_mutex_timedlock.c
	(__pthread_mutex_clocklock_common): Rename from
	__pthread_mutex_timedlock and add clockid parameter. Pass this
	parameter to lll_clocklock and lll_clocklock_elision in place of
	CLOCK_REALTIME. (__pthread_mutex_clocklock): New function to add
	LIBC_PROBE and validate clockid parameter before calling
	__pthread_mutex_clocklock_common. (__pthread_mutex_timedlock): New
	implementation to add LIBC_PROBE and calls
	__pthread_mutex_clocklock_common passing CLOCK_REALTIME as the
	clockid.
	* nptl/Makefile: Add tst-mutex11.c.
	* nptl/tst-abstime.c (th): Add tests for pthread_mutex_clocklock.
	* nptl/tst-mutex11.c: New tests for passing invalid and unsupported
	clockid parameters to pthread_mutex_clocklock.
	* nptl/tst-mutex5.c (do_test_clock): Rename from do_test and take
	clockid parameter to indicate which clock to be used. Call
	pthread_mutex_timedlock or pthread_mutex_clocklock as appropriate.
	(do_test): Call do_test_clock to separately test
	pthread_mutex_timedlock, pthread_mutex_clocklock(CLOCK_REALTIME)
	and pthread_mutex_clocklock(CLOCK_MONOTONIC).
	* nptl/tst-mutex9.c: Likewise.
	* nptl/Versions (GLIBC_2.30): Add pthread_mutex_clocklock.
	* sysdeps/unix/sysv/linux/aarch64/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/alpha/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/arm/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/csky/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/hppa/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/i386/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/ia64/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/nios2/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/riscv/rv64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sh/libpthread.abilist (GLIBC_2.30):
	Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libpthread.abilist
	(GLIBC_2.30): Likewise.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12 13:36:25 +00:00
Mike Crowe
59213094c8 nptl: Rename lll_timedlock to lll_clocklock and add clockid parameter
Rename lll_timedlock to lll_clocklock and add clockid
parameter to indicate the clock that the abstime parameter should
be measured against in preparation for adding
pthread_mutex_clocklock.

The name change mirrors the naming for the exposed pthread functions:

 timed => absolute timeout measured against CLOCK_REALTIME (or clock
          specified by attribute in the case of pthread_cond_timedwait.)

 clock => absolute timeout measured against clock specified in preceding
          parameter.

	* sysdeps/nptl/lowlevellock.h (lll_clocklock): Rename from
	lll_timedlock and add clockid parameter. (__lll_clocklock): Rename
	from __lll_timedlock and add clockid parameter.
	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h (lll_clocklock):
	Likewise.
	* nptl/lll_timedlock_wait.c (__lll_clocklock_wait): Rename from
	__lll_timedlock_wait and add clockid parameter. Use __clock_gettime
	rather than __gettimeofday so that clockid can be used. This means
	that conversion from struct timeval is no longer required.
	* sysdeps/sparc/sparc32/lowlevellock.c (lll_clocklock_wait):
	Likewise.
	* sysdeps/sparc/sparc32/lll_timedlock_wait.c: Update comment to
	refer to __lll_clocklock_wait rather than __lll_timedlock_wait.
	* nptl/pthread_mutex_timedlock.c (lll_clocklock_elision): Rename
	from lll_timedlock_elision, add clockid parameter and use
	meaningful names for other parameters. (__pthread_mutex_timedlock):
	Pass CLOCK_REALTIME where necessary to lll_clocklock and
	lll_clocklock_elision.
	* sysdeps/unix/sysv/linux/powerpc/lowlevellock.h
	(lll_clocklock_elision): Rename from lll_timedlock_elision and add
	clockid parameter. (__lll_clocklock_elision): Rename from
	__lll_timedlock_elision and add clockid parameter.
	* sysdeps/unix/sysv/linux/s390/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/elision-timed.c
	(__lll_lock_elision): Call __lll_clocklock_elision rather than
	__lll_timedlock_elision. (EXTRAARG): Add clockid parameter.
	(LLL_LOCK): Likewise.
	* sysdeps/unix/sysv/linux/s390/elision-timed.c: Likewise.
	* sysdeps/unix/sysv/linux/x86/elision-timed.c: Likewise.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12 13:36:25 +00:00
Mike Crowe
e996fa72a9 nptl: Add POSIX-proposed pthread_rwlock_clockrdlock & pthread_rwlock_clockwrlock
Add:
 int pthread_rwlock_clockrdlock (pthread_rwlock_t *rwlock,
                                 clockid_t clockid,
                                 const struct timespec *abstime)
and:
 int pthread_rwlock_clockwrlock (pthread_rwlock_t *rwlock,
                                 clockid_t clockid,
                                 const struct timespec *abstime)

which behave like pthread_rwlock_timedrdlock and
pthread_rwlock_timedwrlock respectively, except they always measure
abstime against the supplied clockid. The functions currently support
CLOCK_REALTIME and CLOCK_MONOTONIC and return EINVAL if any other
clock is specified.

	* sysdeps/nptl/pthread.h: Add pthread_rwlock_clockrdlock and
	pthread_wrlock_clockwrlock.
	* nptl/Makefile: Build pthread_rwlock_clockrdlock.c and
	pthread_rwlock_clockwrlock.c.
	* nptl/pthread_rwlock_clockrdlock.c: Implement
	pthread_rwlock_clockrdlock.
	* nptl/pthread_rwlock_clockwrlock.c: Implement
	pthread_rwlock_clockwrlock.
	* nptl/pthread_rwlock_common.c (__pthread_rwlock_rdlock_full): Add
	clockid parameter and verify that it indicates a supported clock on
	entry so that we fail even if it doesn't end up being used. Pass
	that clock on to futex_abstimed_wait when necessary.
	(__pthread_rwlock_wrlock_full): Likewise.
	* nptl/pthread_rwlock_rdlock.c: (__pthread_rwlock_rdlock): Pass
	CLOCK_REALTIME to __pthread_rwlock_rdlock_full even though it won't
	be used because there's no timeout.
	* nptl/pthread_rwlock_wrlock.c (__pthread_rwlock_wrlock): Pass
	CLOCK_REALTIME to __pthread_rwlock_wrlock_full even though it won't
	be used because there is no timeout.
	* nptl/pthread_rwlock_timedrdlock.c (pthread_rwlock_timedrdlock):
	Pass CLOCK_REALTIME to __pthread_rwlock_rdlock_full since abstime
	uses that clock.
	* nptl/pthread_rwlock_timedwrlock.c (pthread_rwlock_timedwrlock):
	Pass CLOCK_REALTIME to __pthread_rwlock_wrlock_full since abstime
	uses that clock.
	* sysdeps/unix/sysv/linux/aarch64/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/alpha/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/arm/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/csky/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/hppa/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/i386/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/ia64/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/nios2/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/riscv/rv64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sh/libpthread.abilist (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* nptl/tst-abstime.c (th): Add pthread_rwlock_clockrdlock and
	pthread_rwlock_clockwrlock timeout tests to match the existing
	pthread_rwlock_timedrdloock and pthread_rwlock_timedwrlock tests.
	* nptl/tst-rwlock14.c (do_test): Likewise.
	* nptl/tst-rwlock6.c Invent verbose_printf macro, and use for
	ancillary output throughout. (tf): Accept thread_args structure so
	that rwlock, a clockid and function name can be passed to the
	thread. (do_test_clock): Rename from do_test. Accept clockid
	parameter to specify test clock. Use the magic clockid value of
	CLOCK_USE_TIMEDLOCK to indicate that pthread_rwlock_timedrdlock and
	pthread_rwlock_timedwrlock should be tested, otherwise pass the
	specified clockid to pthread_rwlock_clockrdlock and
	pthread_rwlock_clockwrlock. Use xpthread_create and xpthread_join.
	(do_test): Call do_test_clock to test each clockid in turn.
	* nptl/tst-rwlock7.c: Likewise.
	* nptl/tst-rwlock9.c (writer_thread, reader_thread): Accept
	thread_args structure so that the (now int) thread number, the
	clockid and the function name can be passed to the thread.
	(do_test_clock): Renamed from do_test. Pass the necessary
	thread_args when creating the reader and writer threads. Use
	xpthread_create and xpthread_join.
	(do_test): Call do_test_clock to test each clockid in turn.
	* manual/threads.texi: Add documentation for
	pthread_rwlock_clockrdlock and pthread_rwlock_clockwrclock.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12 13:36:24 +00:00
Mike Crowe
afe4de7d28 nptl: Add POSIX-proposed pthread_cond_clockwait
Add:

 int pthread_cond_clockwait (pthread_cond_t *cond,
                             pthread_mutex_t *mutex,
                             clockid_t clockid,
                             const struct timespec *abstime)

which behaves just like pthread_cond_timedwait except it always measures
abstime against the supplied clockid. Currently supports CLOCK_REALTIME
and
CLOCK_MONOTONIC and returns EINVAL if any other clock is specified.

Includes feedback from many others. This function was originally
proposed[1] as pthread_cond_timedwaitonclock_np, but The Austin Group
preferred the new name.

	* nptl/Makefile: Add tst-cond26 and tst-cond27
	* nptl/Versions (GLIBC_2.30): Add pthread_cond_clockwait
	* sysdeps/nptl/pthread.h: Likewise
	* nptl/forward.c: Add __pthread_cond_clockwait
	* nptl/forward.c: Likewise
	* nptl/pthreadP.h: Likewise
	* sysdeps/nptl/pthread-functions.h: Likewise
	* nptl/pthread_cond_wait.c (__pthread_cond_wait_common): Add
	clockid parameter and comment describing why we don't need to
	check
	its value. Use that value when calling
	futex_abstimed_wait_cancelable rather than reading the clock
	from
	the flags. (__pthread_cond_wait): Pass unused clockid parameter.
	(__pthread_cond_timedwait): Read clock from flags and pass it to
	__pthread_cond_wait_common. (__pthread_cond_clockwait): Add new
	function with weak alias from pthread_cond_clockwait.
	* sysdeps/mach/hurd/i386/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/aarch64/libpthread.abilist
	* (GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/alpha/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/arm/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/csky/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/hppa/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/i386/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/ia64/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/nios2/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/riscv/rv64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sh/libpthread.abilist (GLIBC_2.30):
	* Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libpthread.abilist
	(GLIBC_2.30): Likewise.
	* nptl/tst-cond11.c (run_test): Support testing
	pthread_cond_clockwait too by using a special magic
	CLOCK_USE_ATTR_CLOCK value to determine whether to call
	pthread_cond_timedwait or pthread_cond_clockwait. (do_test):
	Pass
	CLOCK_USE_ATTR_CLOCK for existing tests, and add new tests using
	all combinations of CLOCK_MONOTONIC and CLOCK_REALTIME.
	* ntpl/tst-cond26.c: New test for passing unsupported and
	* invalid
	clocks to pthread_cond_clockwait.
	* nptl/tst-cond27.c: Add test similar to tst-cond5.c, but using
	struct timespec and pthread_cond_clockwait.
	* manual/threads.texi: Document pthread_cond_clockwait. The
	* comment
	was provided by Carlos O'Donell.

[1] https://sourceware.org/ml/libc-alpha/2015-07/msg00193.html

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12 13:36:24 +00:00
Mike Crowe
99d01ffcc3 nptl: Add clockid parameter to futex timed wait calls
In preparation for adding POSIX clockwait variants of timedwait functions,
add a clockid_t parameter to futex_abstimed_wait functions and pass
CLOCK_REALTIME from all callers for the time being.

Replace lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset
which takes a clockid_t parameter rather than the magic clockbit.

	* sysdeps/nptl/lowlevellock-futex.h,
	sysdeps/unix/sysv/linux/lowlevellock-futex.h: Replace
	lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset that
	takes a clockid rather than a special clockbit.
	* sysdeps/nptl/lowlevellock-futex.h: Add
	lll_futex_supported_clockid so that client functions can check
	whether their clockid parameter is valid even if they don't
	ultimately end up calling lll_futex_clock_wait_bitset.
	* sysdeps/nptl/futex-internal.h,
	sysdeps/unix/sysv/linux/futex-internal.h
	(futex_abstimed_wait, futex_abstimed_wait_cancelable): Add
	clockid_t parameter to indicate which clock the absolute time
	passed should be measured against. Pass that clockid onto
	lll_futex_clock_wait_bitset. Add invalid clock as reason for
	returning -EINVAL.
	* sysdeps/nptl/futex-internal.h,
	sysdeps/unix/sysv/linux/futex-internal.h: Introduce
	futex_abstimed_supported_clockid so that client functions can check
	whether their clockid parameter is valid even if they don't
	ultimately end up calling futex_abstimed_wait.
	* nptl/pthread_cond_wait.c (__pthread_cond_wait_common): Remove
	code to calculate relative timeout for
	__PTHREAD_COND_CLOCK_MONOTONIC_MASK and just pass CLOCK_MONOTONIC
	or CLOCK_REALTIME as required to futex_abstimed_wait_cancelable.
	* nptl/pthread_rwlock_common (__pthread_rwlock_rdlock_full)
	(__pthread_wrlock_full), nptl/sem_waitcommon (do_futex_wait): Pass
	additional CLOCK_REALTIME to futex_abstimed_wait_cancelable.
	* nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock):
	Switch to lll_futex_clock_wait_bitset and pass CLOCK_REALTIME

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-07-12 13:36:23 +00:00
Adhemerval Zanella
c50e1c263e x86: Remove arch-specific low level lock implementation
This patch removes the arch-specific x86 assembly implementation for
low level locking and consolidate both 64 bits and 32 bits in a
single implementation.

Different than other architectures, x86 lll_trylock, lll_lock, and
lll_unlock implements a single-thread optimization to avoid atomic
operation, using cmpxchgl instead.  This patch implements by using
the new single-thread.h definitions in a generic way, although using
the previous semantic.

The lll_cond_trylock, lll_cond_lock, and lll_timedlock just use
atomic operations plus calls to lll_lock_wait*.

For __lll_lock_wait_private and __lll_lock_wait the generic implemtation
there is no indication that assembly implementation is required
performance-wise.

Checked on x86_64-linux-gnu and i686-linux-gnu.

	* sysdeps/nptl/lowlevellock.h (__lll_trylock): New macro.
	(lll_trylock): Call __lll_trylock.
	* sysdeps/unix/sysv/linux/i386/libc-lowlevellock.S: Remove file.
	* sysdeps/unix/sysv/linux/i386/lll_timedlock_wait.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lll_timedlock_wait.c: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/lowlevellock.h: New file.
	* sysdeps/unix/sysv/linux/x86_64/cancellation.S: Include
	lowlevellock-futex.h.
2019-05-14 08:48:02 -03:00
Adhemerval Zanella
959aff9fa2 Assume LLL_LOCK_INITIALIZER is 0
Since hppa is not an outlier anymore regarding LLL_LOCK_INITIALIZER value,
we can now assume it 0 for all architectures.

Checked on a build for all major ABIs.

	* nptl/nptl-init.c (__pthread_initialize_minimal_internal): Remove
	initialization for LLL_LOCK_INITIALIZER different than 0.
	* nptl/old_pthread_cond_broadcast.c (__pthread_cond_broadcast_2_0):
	Assume LLL_LOCK_INITIALIZER being 0.
	* nptl/old_pthread_cond_signal.c (__pthread_cond_signal_2_0): Likewise.
	* nptl/old_pthread_cond_timedwait.c (__pthread_cond_timedwait_2_0):
	Likewise.
	* nptl/old_pthread_cond_wait.c (__pthread_cond_wait_2_0): Likewise.
	* sysdeps/nptl/libc-lockP.h (__libc_lock_define_initialized): Likewise.
2019-05-14 08:44:03 -03:00
Adhemerval Zanella
38cc11daa4 nptl: Remove pthread_clock_gettime pthread_clock_settime
This patch removes CLOCK_THREAD_CPUTIME_ID and CLOCK_PROCESS_CPUTIME_ID support
from clock_gettime and clock_settime generic implementation.  For Linux, kernel
already provides supports through the syscall and Hurd HTL lacks
__pthread_clock_gettime and __pthread_clock_settime internal implementation.

As described in clock_gettime man-page [1] on 'Historical note for SMP
system', implementing CLOCK_{THREAD,PROCESS}_CPUTIME_ID with timer registers
is error-prone and susceptible to timing and accurary issues that the libc
can not deal without kernel support.

This allows removes unused code which, however, still incur in some runtime
overhead in thread creation (the struct pthread cpuclock_offset
initialization).

If hurd eventually wants to support them it should either either implement as
a kernel facility (or something related due its architecture) or in system
specific implementation.

Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu. I also
checked on a i686-gnu build.

	* nptl/Makefile (libpthread-routines): Remove pthread_clock_gettime and
	pthread_clock_settime.
	* nptl/pthreadP.h (__find_thread_by_id): Remove prototype.
	* elf/dl-support.c [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset): Remove.
	(_dl_non_dynamic_init): Remove _dl_cpuclock_offset setting.
	* elf/rtld.c (_dl_start_final): Likewise.
	* nptl/allocatestack.c (__find_thread_by_id): Remove function.
	* sysdeps/generic/ldsodefs.h [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset):
	Remove.
	* sysdeps/mach/hurd/dl-sysdep.c [!HP_TIMING_NOAVAIL]
	(_dl_cpuclock_offset): Remove.
	* nptl/descr.h (struct pthread): Rename cpuclock_offset to
	cpuclock_offset_ununsed.
	* nptl/nptl-init.c (__pthread_initialize_minimal_internal): Remove
	cpuclock_offset set.
	* nptl/pthread_create.c (START_THREAD_DEFN): Likewise.
	* sysdeps/nptl/fork.c (__libc_fork): Likewise.
	* nptl/pthread_clock_gettime.c: Remove file.
	* nptl/pthread_clock_settime.c: Likewise.
	* sysdeps/unix/clock_gettime.c (hp_timing_gettime): Remove function.
	[HP_TIMING_AVAIL] (realtime_gettime): Remove CLOCK_THREAD_CPUTIME_ID
	and CLOCK_PROCESS_CPUTIME_ID support.
	* sysdeps/unix/clock_settime.c (hp_timing_gettime): Likewise.
	[HP_TIMING_AVAIL] (realtime_gettime): Likewise.
	* sysdeps/posix/clock_getres.c (hp_timing_getres): Likewise.
	[HP_TIMING_AVAIL] (__clock_getres): Likewise.
	* sysdeps/unix/clock_nanosleep.c (CPUCLOCK_P, INVALID_CLOCK_P):
	Likewise.
	(__clock_nanosleep): Remove CPUCLOCK_P and INVALID_CLOCK_P usage.

[1] http://man7.org/linux/man-pages/man2/clock_gettime.2.html
2019-03-22 15:37:43 -03:00
Adhemerval Zanella
0ddb7ea842 nptl: Assume __ASSUME_FUTEX_CLOCK_REALTIME support
This patch assumes realtime clock support for nptl and thus removes
all the associated code.

For __pthread_mutex_timedlock the fallback usage for the case where
lll_futex_timed_wait_bitset it not set define is also removed. The
generic lowlevellock-futex.h always define it, so for NPTL code the
check always yield true.

Checked on x86_64-linux-gnu and i686-linux-gnu.

	* nptl/nptl-init.c (__have_futex_clock_realtime,
	__have_futex_clock_realtime): Remove definition.
	(__pthread_initialize_minimal_internal): Remove FUTEX_CLOCK_REALTIME
	check test for !__ASSUME_FUTEX_CLOCK_REALTIME.
	* nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Assume
	__ASSUME_FUTEX_CLOCK_REALTIME support.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/kernel-features.h
	(__ASSUME_FUTEX_CLOCK_REALTIME): Remove.
	* sysdeps/nptl/lowlevellock-futex.h (lll_futex_timed_wait_bitset):
	Adjust comment.
2019-03-05 16:28:20 -03:00
Florian Weimer
a198d37ade Move remaining nptl_db headers to sysdeps/nptl
sys/procfs.h was already using this sysdeps directory.

This avoids the need for  nptl-specific wrapper headers under
include/, a generic location in the source tree.
2019-02-16 08:25:16 +01:00
Adhemerval Zanella
eb76e5b465 nptl: Reinstate pthread_timedjoin_np as a cancellation point (BZ#24215)
Patch ce7eb0e903 ("nptl: Cleanup cancellation macros") changed the
join sequence for internal common __pthread_timedjoin_ex to use the
new macro lll_wait_tid.  The idea was this macro would issue the
cancellable futex operation depending whether the timeout is used or
not.  However if a timeout is used, __lll_timedwait_tid is called and
it is not a cancellable entrypoint.

This patch fixes it by simplifying the code in various ways:

  - Instead of adding the cancellation handling on __lll_timedwait_tid,
    it moves the generic implementation to pthread_join_common.c (called
    now timedwait_tid with some fixes to use the correct type for pid).

  - The llvm_wait_tid macro is removed, along with its replication on
    x86_64, i686, and sparc arch-specific lowlevellock.h.

  - sparc32 __lll_timedwait_tid is also removed, since the code is similar
    to generic one.

  - x86_64 and i386 provides arch-specific __lll_timedwait_tid which is
    also removed since they are similar in functionality to generic C code
    and there is no indication it is better than compiler generated code.

New tests, tst-join8 and tst-join9, are provided to check if
pthread_timedjoin_np acts as a cancellation point.

Checked on x86_64-linux-gnu, i686-linux-gnu, sparcv9-linux-gnu, and
aarch64-linux-gnu.

	[BZ #24215]
	* nptl/Makefile (lpthread-routines): Remove lll_timedwait_tid.
	(tests): Add tst-join8 tst-join9.
	* nptl/lll_timedwait_tid.c: Remove file.
	* sysdeps/sparc/sparc32/lll_timedwait_tid.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/lll_timedwait_tid.c: Likewise.
	* sysdeps/sysv/linux/x86_64/lll_timedwait_tid.c: Likewise.
	* nptl/pthread_join_common.c (timedwait_tid): New function.
	(__pthread_timedjoin_ex): Act as cancellation entrypoint is block
	is set.
	* nptl/tst-join5.c (thread_join): New function.
	(tf1, tf2, do_test): Use libsupport and add pthread_timedjoin_np
	check.
	* nptl/tst-join8.c: New file.
	* nptl/tst-join9.c: Likewise.
	* sysdeps/nptl/lowlevellock-futex.h (lll_futex_wait_cancel,
	lll_futex_timed_wait_cancel): Add generic macros.
	* sysdeps/nptl/lowlevellock.h (__lll_timedwait_tid, lll_wait_tid):
	Remove definitions.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Likewise.
	* sysdeps/sparc/sparc32/lowlevellock.c (__lll_timedwait_tid):
	Remove function.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.S (__lll_timedwait_tid):
	Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/lowlevellock-futex.h
	(lll_futex_timed_wait_cancel): New macro.
2019-02-14 18:11:15 -02:00
Florian Weimer
669ff911e2 nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161]
Commit 27761a1042 ("Refactor atfork
handlers") introduced a lock, atfork_lock, around fork handler list
accesses.  It turns out that this lock occasionally results in
self-deadlocks in malloc/tst-mallocfork2:

(gdb) bt
#0  __lll_lock_wait_private ()
    at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:63
#1  0x00007f160c6f927a in __run_fork_handlers (who=(unknown: 209394016),
    who@entry=atfork_run_prepare) at register-atfork.c:116
#2  0x00007f160c6b7897 in __libc_fork () at ../sysdeps/nptl/fork.c:58
#3  0x00000000004027d6 in sigusr1_handler (signo=<optimized out>)
    at tst-mallocfork2.c:80
#4  sigusr1_handler (signo=<optimized out>) at tst-mallocfork2.c:64
#5  <signal handler called>
#6  0x00007f160c6f92e4 in __run_fork_handlers (who=who@entry=atfork_run_parent)
    at register-atfork.c:136
#7  0x00007f160c6b79a2 in __libc_fork () at ../sysdeps/nptl/fork.c:152
#8  0x0000000000402567 in do_test () at tst-mallocfork2.c:156
#9  0x0000000000402dd2 in support_test_main (argc=1, argv=0x7ffc81ef1ab0,
    config=config@entry=0x7ffc81ef1970) at support_test_main.c:350
#10 0x0000000000402362 in main (argc=<optimized out>, argv=<optimized out>)
    at ../support/test-driver.c:168

If no locking happens in the single-threaded case (where fork is
expected to be async-signal-safe), this deadlock is avoided.
(pthread_atfork is not required to be async-signal-safe, so a fork
call from a signal handler interrupting pthread_atfork is not
a problem.)
2019-02-08 12:46:19 +01:00
Adhemerval Zanella
ce7eb0e903 nptl: Cleanup cancellation macros
This patch wraps all uses of *_{enable,disable}_asynccancel and
and *_CANCEL_{ASYNC,RESET} in either already provided macros
(lll_futex_timed_wait_cancel) or creates new ones if the
functionality is not provided (SYSCALL_CANCEL_NCS, lll_futex_wait_cancel,
and lll_futex_timed_wait_cancel).

Also for some generic implementations, the direct call of the macros
are removed since the underlying symbols are suppose to provide
cancellation support.

This is a priliminary patch intended to simplify the work required
for BZ#12683 fix.  It is a refactor change, no semantic changes are
expected.

Checked on x86_64-linux-gnu and i686-linux-gnu.

	* nptl/pthread_join_common.c (__pthread_timedjoin_ex): Use
	lll_wait_tid with timeout.
	* nptl/sem_wait.c (__old_sem_wait): Use lll_futex_wait_cancel.
	* sysdeps/nptl/aio_misc.h (AIO_MISC_WAIT): Use
	futex_reltimed_wait_cancelable for cancelabla mode.
	* sysdeps/nptl/gai_misc.h (GAI_MISC_WAIT): Likewise.
	* sysdeps/posix/open64.c (__libc_open64): Do not call cancelation
	macros.
	* sysdeps/posix/sigwait.c (__sigwait): Likewise.
	* sysdeps/posix/waitid.c (__sigwait): Likewise.
	* sysdeps/unix/sysdep.h (__SYSCALL_CANCEL_CALL,
	SYSCALL_CANCEL_NCS): New macro.
	* sysdeps/nptl/lowlevellock.h (lll_wait_tid): Add timeout argument.
	(lll_timedwait_tid): Remove macro.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.h (lll_wait_tid):
	Likewise.
	(lll_timedwait_tid): Likewise.
	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h (lll_wait_tid):
	Likewise.
	(lll_timedwait_tid): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (lll_wait_tid):
	Likewise.
	(lll_timedwait_tid): Likewise.
	* sysdeps/unix/sysv/linux/clock_nanosleep.c (__clock_nanosleep):
	Use INTERNAL_SYSCALL_CANCEL.
	* sysdeps/unix/sysv/linux/futex-internal.h
	(futex_reltimed_wait_cancelable): Use LIBC_CANCEL_{ASYNC,RESET}
	instead of __pthread_{enable,disable}_asynccancel.
	* sysdeps/unix/sysv/linux/lowlevellock-futex.h
	(lll_futex_wait_cancel): New macro.
2019-01-03 18:38:16 -02:00
Joseph Myers
04277e02d7 Update copyright dates with scripts/update-copyrights.
* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.
2019-01-01 00:11:28 +00:00
Zack Weinberg
4e2f43f842 Use PRINTF_FORTIFY instead of _IO_FLAGS2_FORTIFY (bug 11319)
The _chk variants of all of the printf functions become much simpler.
This is the last thing that we needed _IO_acquire_lock_clear_flags2
for, so it can go as well.  I took the opportunity to make the headers
included and the names of all local variables consistent across all the
affected files.

Since we ultimately want to get rid of __no_long_double as well, it
must be possible to get all of the nontrivial effects of the _chk
functions by calling the _internal functions with appropriate flags.
For most of the __(v)xprintf_chk functions, this is covered by
PRINTF_FORTIFY plus some up-front argument checks that can be
duplicated.  However, __(v)sprintf_chk installs a custom jump table so
that it can crash instead of overflowing the output buffer.  This
functionality is moved to __vsprintf_internal, which now has a
'maxlen' argument like __vsnprintf_internal; to get the unsafe
behavior of ordinary (v)sprintf, pass -1 for that argument.

obstack_printf_chk and obstack_vprintf_chk are no longer in the same
file.

As a side-effect of the unification of both fortified and non-fortified
vdprintf initialization, this patch fixes bug 11319 for __dprintf_chk
and __vdprintf_chk, which was previously fixed only for dprintf and
vdprintf by the commit

commit 7ca890b88e
Author: Ulrich Drepper <drepper@redhat.com>
Date:   Wed Feb 24 16:07:57 2010 -0800

    Fix reporting of I/O errors in *dprintf functions.

This patch adds a test case to avoid regressions.

Tested for powerpc and powerpc64le.
2018-12-05 18:15:43 -02:00
Kemi Wang
6310e6be9b Mutex: Add pthread mutex tunables
This patch does not have any functionality change, we only provide a spin
count tunes for pthread adaptive spin mutex. The tunable
glibc.pthread.mutex_spin_count tunes can be used by system administrator to
squeeze system performance according to different hardware capabilities and
workload characteristics.

The maximum value of spin count is limited to 32767 to avoid the overflow
of mutex->__data.__spins variable with the possible type of short in
pthread_mutex_lock ().

The default value of spin count is set to 100 with the reference to the
previous number of times of spinning via trylock. This value would be
architecture-specific and can be tuned with kinds of benchmarks to fit most
cases in future.

I would extend my appreciation sincerely to H.J.Lu for his help to refine
this patch series.

	* manual/tunables.texi (POSIX Thread Tunables): New node.
	* nptl/Makefile (libpthread-routines): Add pthread_mutex_conf.
	* nptl/nptl-init.c: Include pthread_mutex_conf.h
	(__pthread_initialize_minimal_internal) [HAVE_TUNABLES]: Call
	 __pthread_tunables_init.
	* nptl/pthreadP.h (MAX_ADAPTIVE_COUNT): Remove.
	(max_adaptive_count): Define.
	* nptl/pthread_mutex_conf.c: New file.
	* nptl/pthread_mutex_conf.h: New file.
	* sysdeps/generic/adaptive_spin_count.h: New file.
	* sysdeps/nptl/dl-tunables.list: New file.
	* nptl/pthread_mutex_lock.c (__pthread_mutex_lock): Use
	max_adaptive_count () not MAX_ADAPTIVE_COUNT.
	* nptl/pthread_mutex_timedlock.c (__pthrad_mutex_timedlock):
	Likewise.

Suggested-by: Andi Kleen <andi.kleen@intel.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Signed-off-by: Kemi.wang <kemi.wang@intel.com>
2018-12-01 08:19:20 -08:00
Stefan Liebler
403b4feb22 Fix race in pthread_mutex_lock while promoting to PTHREAD_MUTEX_ELISION_NP [BZ #23275]
The race leads either to pthread_mutex_destroy returning EBUSY
or triggering an assertion (See description in bugzilla).

This patch is fixing the race by ensuring that the elision path is
used in all cases if elision is enabled by the GLIBC_TUNABLES framework.

The __kind variable in struct __pthread_mutex_s is accessed concurrently.
Therefore we are now using the atomic macros.

The new testcase tst-mutex10 is triggering the race on s390x and intel.
Presumably also on power, but I don't have access to a power machine
with lock-elision. At least the code for power is the same as on the other
two architectures.

ChangeLog:

	[BZ #23275]
	* nptl/tst-mutex10.c: New File.
	* nptl/Makefile (tests): Add tst-mutex10.
	(tst-mutex10-ENV): New variable.
	* sysdeps/unix/sysv/linux/s390/force-elision.h: (FORCE_ELISION):
	Ensure that elision path is used if elision is available.
	* sysdeps/unix/sysv/linux/powerpc/force-elision.h (FORCE_ELISION):
	Likewise.
	* sysdeps/unix/sysv/linux/x86/force-elision.h: (FORCE_ELISION):
	Likewise.
	* nptl/pthreadP.h (PTHREAD_MUTEX_TYPE, PTHREAD_MUTEX_TYPE_ELISION)
	(PTHREAD_MUTEX_PSHARED): Use atomic_load_relaxed.
	* nptl/pthread_mutex_consistent.c (pthread_mutex_consistent): Likewise.
	* nptl/pthread_mutex_getprioceiling.c (pthread_mutex_getprioceiling):
	Likewise.
	* nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full)
	(__pthread_mutex_cond_lock_adjust): Likewise.
	* nptl/pthread_mutex_setprioceiling.c (pthread_mutex_setprioceiling):
	Likewise.
	* nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Likewise.
	* nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock): Likewise.
	* nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_full): Likewise.
	* sysdeps/nptl/bits/thread-shared-types.h (struct __pthread_mutex_s):
	Add comments.
	* nptl/pthread_mutex_destroy.c (__pthread_mutex_destroy):
	Use atomic_load_relaxed and atomic_store_relaxed.
	* nptl/pthread_mutex_init.c (__pthread_mutex_init):
	Use atomic_store_relaxed.
2018-10-17 12:23:04 +02:00
Paul Pluzhnikov
a6e8926f8d [BZ #20271] Add newlines in __libc_fatal calls. 2018-08-31 18:04:32 -07:00
Adhemerval Zanella
d6499b7039 Fix ISO C threads installed header and HURD assumption
Set installed NPTL header as the expected one (instead of an
internal one for glibc testsuite) and add a hurd specific
stdc-predef with __STDC_NO_THREADS__.

Checked on both i686-linux-gnu and i686-gnu that both threads.h
and stdc-predef.h are the expected ones.

	* nptl/threads.h: Move to ...
	* sysdeps/nptl/threads.h: ... here.
	* sysdeps/hurd/stdc-predef.h: New file.
2018-07-25 17:27:45 -03:00
Adhemerval Zanella
9faaf93850 Fix C11 conformance issues
Remove conformace assumption of NPTL implementation for ISO C threads
and revert wrong libcrypt addition on linknamespace-libs-XPG4.

The i686-gnu target now shows two new conformance failures:

FAIL: conform/ISO11/threads.h/conform
FAIL: conform/ISO11/threads.h/linknamespace

It is expected due missing HTL ISO C threads support and both conformance
.out files indicates the reason ("#error "HTL does not implement ISO C
threads").

Checked on i686-linux-gnu and i686-gnu.

	* include/threads.h: Move to ...
	* sysdeps/nptl/threads.h: ... here.
	* sysdeps/htl/threads.h: New file.
	* conform/Makefile (linknamespace-libs-ISO11): Use
	static-thread-library instead of linking libpthread.
	(linknamespace-libs-XPG4): Revert wrong libcrypt.a addition.
2018-07-25 12:02:32 -03:00
Carlos O'Donell
2827ab990a libc: Extend __libc_freeres framework (Bug 23329).
The __libc_freeres framework does not extend to non-libc.so objects.
This causes problems in general for valgrind and mtrace detecting
unfreed objects in both libdl.so and libpthread.so.  This change is
a pre-requisite to properly moving the malloc hooks out of malloc
since such a move now requires precise accounting of all allocated
data before destructors are run.

This commit adds a proper hook in libc.so.6 for both libdl.so and
for libpthread.so, this ensures that shm-directory.c which uses
freeit () to free memory is called properly.  We also remove the
nptl_freeres hook and fall back to using weak-ref-and-check idiom
for a loaded libpthread.so, thus making this process similar for
all DSOs.

Lastly we follow best practice and use explicit free calls for
both libdl.so and libpthread.so instead of the generic hook process
which has undefined order.

Tested on x86_64 with no regressions.

Signed-off-by: DJ Delorie <dj@redhat.com>
Signed-off-by: Carlos O'Donell <carlos@redhat.com>
2018-06-29 22:39:06 -04:00
Andreas Schwab
0555c47719 Fix comment typo 2018-05-08 14:59:13 +02:00
Stefan Liebler
1660901840 Fix blocking pthread_join. [BZ #23137]
On s390 (31bit) if glibc is build with -Os, pthread_join sometimes
blocks indefinitely. This is e.g. observable with
testcase intl/tst-gettext6.

pthread_join is calling lll_wait_tid(tid), which performs the futex-wait
syscall in a loop as long as tid != 0 (thread is alive).

On s390 (and build with -Os), tid is loaded from memory before
comparing against zero and then the tid is loaded a second time
in order to pass it to the futex-wait-syscall.
If the thread exits in between, then the futex-wait-syscall is
called with the value zero and it waits until a futex-wake occurs.
As the thread is already exited, there won't be a futex-wake.

In lll_wait_tid, the tid is stored to the local variable __tid,
which is then used as argument for the futex-wait-syscall.
But unfortunately the compiler is allowed to reload the value
from memory.

With this patch, the tid is loaded with atomic_load_acquire.
Then the compiler is not allowed to reload the value for __tid from memory.

ChangeLog:

	[BZ #23137]
	* sysdeps/nptl/lowlevellock.h (lll_wait_tid):
	Use atomic_load_acquire to load __tid.
2018-05-04 10:00:59 +02:00
Tulio Magno Quites Machado Filho
81b49e9692 Increase robustness of internal dlopen() by using RTLD_NOW [BZ #22766]
Prevent random runtime crashes due to missing symbols caused by mixed
libnss_* versions.

	[BZ #22766]
	* include/dlfcn.h [__libc_dl_open]: Replace RTLD_LAZY with RTLD_NOW.
	* sysdeps/gnu/unwind-resume.c (__lib_gcc_s_init): Replace
	__libc_dlopen_mode() using RTLD_NOW with __libc_dlopen.
	* sysdeps/nptl/unwind-forcedunwind.c: Likewise.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-04-26 10:41:43 -03:00
Adhemerval Zanella
d2dc5467c6 Filter out NPTL internal signals (BZ #22391)
This patch filters out the internal NPTL signals (SIGCANCEL/SIGTIMER and
SIGSETXID) from signal functions.  GLIBC on Linux requires both signals to
proper implement pthread cancellation, posix timers, and set*id posix
thread synchronization.

And not filtering out the internal signal is troublesome:

  - A conformant program on a architecture that does not filter out the
    signals might inadvertently disable pthread asynchronous cancellation,
    set*id synchronization or posix timers.

  - It might also to security issues if SIGSETXID is masked and set*id
    functions are called (some threads might have effective user or group
    id different from the rest).

The changes are basically:

  - Change __is_internal_signal to bool and used on all signal function
    that has a signal number as input.  Also for signal function which accepts
    signals sets (sigset_t) it assumes that canonical function were used to
    add/remove signals which lead to some input simplification.

  - Fix tst-sigset.c to avoid check for SIGCANCEL/SIGTIMER and SIGSETXID.
    It is rewritten to check each signal indidually and to check realtime
    signals using canonical macros.

  - Add generic __clear_internal_signals and __is_internal_signal
    version since both symbols are used on generic implementations.

  - Remove superflous sysdeps/nptl/sigfillset.c.

  - Remove superflous SIGTIMER handling on Linux __is_internal_signal
    since it is the same of SIGCANCEL.

  - Remove dangling define and obvious comment on nptl/sigaction.c.

Checked on x86_64-linux-gnu.

	[BZ #22391]
	* nptl/sigaction.c (__sigaction): Use __is_internal_signal to
	check for internal nptl signals.
	* nptl/sigaction.c (__sigaction): Likewise.
	* signal/sigaddset.c (sigaddset): Likewise.
	* signal/sigdelset.c (sigdelset): Likewise.
	* sysdeps/posix/signal.c (__bsd_signal): Likewise.
	* sysdeps/posix/sigset.c (sigset): Call and check sigaddset return
	value.
	* signal/sigfillset.c (sigfillset): User __clear_internal_signals
	to filter out internal nptl signals.
	* signal/tst-sigset.c (do_test): Check ech signal indidually and
	also check realtime signals using standard macros.
	* sysdeps/generic/internal-signals.h (__clear_internal_signals,
	__is_internal_signal, __libc_signal_block_all,
	__libc_signal_block_app, __libc_signal_restore_set): New functions.
	* sysdeps/nptl/sigfillset.c: Remove file.
	* sysdeps/unix/sysv/linux/internal-signals.h (__is_internal_signal):
	Change return to bool.
	(__clear_internal_signals): Remove SIGTIMER clean since it is
	equal to SIGCANEL on Linux.
	* sysdeps/unix/sysv/linux/sigtimedwait.c (__sigtimedwait): Assume
	signal set was constructed using standard functions.

Reported-by: Yury Norov <ynorov@caviumnetworks.com>
2018-04-03 13:30:49 -03:00
Adhemerval Zanella
3dc214977b Refactor Linux ARCH_FORK implementation
This patch refactors the ARCH_FORK macro and the required architecture
specific header to simplify the required architecture definitions
to provide the fork syscall semantic and proper document current
Linux clone ABI variant.

Instead of require the reimplementation of arch-fork.h header, this
patch changes the ARCH_FORK to an inline function with clone ABI
defined by kernel-features.h define.  The generic kernel ABI meant
for newer ports is used as default and redefine if the architecture
requires.

Checked on x86_64-linux-gnu and i686-linux-gnu.  Also with a build
for all the afected ABIs.

	* sysdeps/nptl/fork.c (ARCH_FORK): Replace by auch_fork.
	* sysdeps/unix/sysv/linux/alpha/arch-fork.h: Remove file.
	* sysdeps/unix/sysv/linux/riscv/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/hppa/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/i386/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/ia64/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/m68k/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/nios2/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/tile/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/arch-fork.h: Likewise.
	* sysdeps/unix/sysv/linux/arch-fork.h (arch_fork): New function.
	* sysdeps/unix/sysv/linux/aarch64/kernel-features.h: New file.
	* sysdeps/unix/sysv/linux/riscv/kernel-features.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/kernel-features.h
	(__ASSUME_CLONE_BACKWARDS): Define.
	* sysdeps/unix/sysv/linux/createthread.c (ARCH_CLONE): Define to
	__clone2 if __NR_clone2 is defined.
	* sysdeps/unix/sysv/linux/hppa/kernel-features.h
	(__ASSUME_CLONE_BACKWARDS): Likewise.
	* sysdeps/unix/sysv/linux/i386/kernel-features.h
	(__ASSUME_CLONE_BACKWARDS): Likewise.
	* sysdeps/unix/sysv/linux/ia64/kernel-features.h
	(__ASSUME_CLONE2): Likewise.
	* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
	(__ASSUME_CLONE_BACKWARDS3): Likewise.
	* sysdeps/unix/sysv/linux/kernel-features.h: Document possible clone
	variants and the define architecture can use.
	(__ASSUME_CLONE_DEFAULT): Define as default.
	* sysdeps/unix/sysv/linux/mips/kernel-features.h
	(__ASSUME_CLONE_BACKWARDS): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/kernel-features.h
	(__ASSUME_CLONE_BACKWARDS): Likewise.
	* sysdeps/unix/sysv/linux/s390/kernel-features.h
	(__ASSUME_CLONE_BACKWARDS2): Likewise.
2018-03-07 17:39:40 -03:00
Florian Weimer
bd60ce8652 nptl: Move pthread_atfork to libc_nonshared.a
libpthread_nonshared.a is unused after this, so remove it from the
build.

There is no ABI impact because pthread_atfork was implemented using
__register_atfork in libc even before this change.

pthread_atfork has to be a weak alias because pthread_* names are not
reserved in libc.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-03-01 08:18:48 +01:00
Samuel Thibault
03b540b368 Move NPTL-specific code to NPTL-specific header
* sysdeps/pthread/timer_routines.c: Include <timer_routines.h> instead
	of <nptl/pthreadP.h>
	(thread_attr_compare): Move function to...
	* sysdeps/nptl/timer_routines.h: ... new header.
2018-02-27 00:48:24 +01:00
Adhemerval Zanella
27761a1042 Refactor atfork handlers
Current implementation (sysdeps/nptl/fork.c) replicates the atfork
handlers list backward to invoke the child handlers after fork/clone
syscall.

The internal atfork handlers is implemented as a single-linked list
so a lock-free algorithm can be used, trading fork mulithread call
performance for some code complexity and dynamic stack allocation
(since the backwards list should not fail).

This patch refactor it to use a dynarary instead of a linked list.
It simplifies the external variables need to be exported and also
the internal atfork handler member definition.

The downside is a serialization of fork call in multithread, since to
operate on the dynarray the internal lock should be used.  However
as noted by Florian, it already acquires external locks for malloc
and libio so it is already hitting some lock contention.  Besides,
posix_spawn should be faster and more scalable to run external programs
in multithread environments.

Checked on x86_64-linux-gnu.

	* nptl/Makefile (routines): Remove unregister-atfork.
	* nptl/register-atfork.c (fork_handler_pool): Remove variable.
	(fork_handler_alloc): Remove function.
	(fork_handlers, fork_handler_init): New variables.
	(__fork_lock): Rename to atfork_lock.
	(__register_atfork, __unregister_atfork, libc_freeres_fn): Rewrite
	to use a dynamic array to add/remove atfork handlers.
	* sysdeps/nptl/fork.c (__libc_fork): Likewise.
	* sysdeps/nptl/fork.h (__fork_lock, __fork_handlers, __linkin_atfork):
	Remove declaration.
	(fork_handler): Remove next, refcntr, and need_signal member.
	(__run_fork_handler_type): New enum.
	(__run_fork_handlers): New prototype.
	* sysdeps/nptl/libc-lockP.h (__libc_atfork): Remove declaration.
2018-02-22 16:43:59 -03:00