Previously, the source file nptl/cancellation.c was compiled multiple
times, for libc, libpthread, librt. This commit switches to a single
implementation, with new __pthread_enable_asynccancel@@GLIBC_PRIVATE,
__pthread_disable_asynccancel@@GLIBC_PRIVATE exports.
The almost-unused CANCEL_ASYNC and CANCEL_RESET macros are replaced
by LIBC_CANCEL_ASYNC and LIBC_CANCEL_ASYNC macros. They call the
__pthread_* functions unconditionally now. The macros are still
needed because shared code uses them; Hurd has different definitions.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
This patch move the single-thread syscall optimization defintions from
syscall-cancel.h to new header file single-thread.h and also move the
cancellation definitions from pthreadP.h to syscall-cancel.h.
The idea is just simplify the inclusion of both syscall-cancel.h and
single-thread.h (without the requirement of including all pthreadP.h
defintions).
No semantic changes expected, checked on a build for all major ABIs.
* nptl/pthreadP.h (CANCEL_ASYNC, CANCEL_RESET, LIBC_CANCEL_ASYNC,
LIBC_CANCEL_RESET, __libc_enable_asynccancel,
__libc_disable_asynccancel, __librt_enable_asynccancel,
__libc_disable_asynccancel, __librt_enable_asynccancel,
__librt_disable_asynccancel): Move to ...
* sysdeps/unix/sysv/linux/sysdep-cancel.h: ... here.
(SINGLE_THREAD_P, RTLD_SINGLE_THREAD_P): Move to ...
* sysdeps/unix/sysv/linux/single-thread.h: ... here.
* sysdeps/generic/single-thread.h: New file.
* sysdeps/unix/sysdep.h: Include single-thread.h.
* sysdeps/unix/sysv/linux/futex-internal.h: Include sysdep-cancel.h.
* sysdeps/unix/sysv/linux/lowlevellock-futex.h: Likewise.
Current GLIBC has two ways to implement the single thread optimization
on syscalls to avoid calling the cancellation path: either by using
global variables (__{libc,pthread}_multiple_thread) or by accessing
the TCB field (defined by TLS_MULTIPLE_THREADS_IN_TCB). Both the
variables and the macros to acces its value are defined in the
architecture sysdep-cancel.h header.
This patch consolidates its definition on only one header,
sysdeps/unix/sysv/linux/sysdep-cancel.h, and adds a new define
(SINGLE_THREAD_BY_GLOBAL) which the architecture defines if it prefer
to use the global variables instead of the TCB field. This is an
optimization, so if the architecture does not define it, the TCB
method will be used as default.
Checked on x86_64-linux-gnu and on a build with major touched
ABIs (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf,
hppa-linux-gnu, i686-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu,
mips-linux-gnu, mips64-linux-gnu, powerpc-linux-gnu,
powerpc64le-linux-gnu, s390-linux-gnu, s390x-linux-gnu, sh4-linux-gnu,
sparcv9-linux-gnu, sparc64-linux-gnu, tilegx-linux-gnu).
* sysdeps/unix/sysv/linux/aarch64/sysdep-cancel.h: Remove file.
* sysdeps/unix/sysv/linux/alpha/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/arm/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/hppa/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/mips/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/nios2/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/sh/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/tile/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h
(SINGLE_THREAD_BY_GLOBAL): Define.
* sysdeps/unix/sysv/linux/aarch64/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/alpha/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/arm/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/hppa/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/microblaze/sysdep.h
(SINGLE_THREAD_BY_GLOBAL): Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
