Commit Graph

16 Commits

Author SHA1 Message Date
Adhemerval Zanella
c701bcc6f4 linux: Consolidate Linux gettimeofday
The IFUNC bypass to vDSO is used when USE_IFUNC_GETTIMEOFDAY is set.
Currently aarch64, powerpc*, and x86 defines it.  Otherwise the
generic implementation is used, which calls clock_gettime.

Checked on aarch64-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu-power4, x86_64-linux-gnu,
and i686-linux-gnu.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2020-01-03 11:21:50 -03:00
Adhemerval Zanella
d0def09ff6 linux: Fix vDSO macros build with time64 interfaces
As indicated on libc-help [1] the ec138c67cb commit broke 32-bit
builds when configured with --enable-kernel=5.1 or higher.  The
scenario 10 from [2] might also occur in this configuration and
INLINE_VSYSCALL will try to use the vDSO symbol and
HAVE_CLOCK_GETTIME64_VSYSCALL does not set HAVE_VSYSCALL prior its
usage.

Also, there is no easy way to just enable the code to use one
vDSO symbol since the macro INLINE_VSYSCALL is redefined if
HAVE_VSYSCALL is set.

Instead of adding more pre-processor handling and making the code
even more convoluted, this patch removes the requirement of defining
HAVE_VSYSCALL before including sysdep-vdso.h to enable vDSO usage.

The INLINE_VSYSCALL is now expected to be issued inside a
HAVE_*_VSYSCALL check, since it will try to use the internal vDSO
pointers.

Both clock_getres and clock_gettime vDSO code for time64_t were
removed since there is no vDSO setup code for the symbol (an
architecture can not set HAVE_CLOCK_GETTIME64_VSYSCALL).

Checked on i686-linux-gnu (default and with --enable-kernel=5.1),
x86_64-linux-gnu, aarch64-linux-gnu, and powerpc64le-linux-gnu.
I also checked against a build to mips64-linux-gnu and
sparc64-linux-gnu.

[1] https://sourceware.org/ml/libc-help/2019-12/msg00014.html
[2] https://sourceware.org/ml/libc-alpha/2019-12/msg00142.html

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2020-01-03 10:02:05 -03:00
Joseph Myers
d614a75396 Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Zack Weinberg
2f2c76e1c8 Make second argument of gettimeofday as 'void *'
Also make the public prototype of gettimeofday declare its second
argument with type "void *" unconditionally, consistent with POSIX.

It is also consistent with POSIX.

Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu.

Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
2019-10-30 17:11:10 -03:00
Adhemerval Zanella
5e46749c64 Use clock_gettime to implement gettimeofday.
Consolidate generic gettimeofday implementation to use clock_gettime.
Linux ports that still provide gettimeofday through vDSO are not
changed.

Remove sysdeps/unix/clock_gettime.c, which implemented clock_gettime
using gettimeofday; new OS ports must provide a real implementation of
clock_gettime.

Rename sysdeps/mach/gettimeofday.c to sysdeps/mach/clock_gettime.c and
convert into an implementation of clock_gettime.  It only supports
CLOCK_REALTIME; Mach does not appear to have any support for monotonic
clocks.  It uses __host_get_time, which provides at best microsecond
resolution.  Hurd is currently using sysdeps/posix/clock_getres.c for
clock_getres; its output for CLOCK_REALTIME is based on
sysconf (_SC_CLK_TCK), and I do not know whether that gives the
correct result.

Unlike settimeofday, there are no known uses of gettimeofday's
vestigial "get time zone" feature that are not bugs.  (The per-process
timezone support in localtime and friends is unrelated, and the
programs that set the kernel's offset between the hardware clock and
UTC do not need to read it back.)  Therefore, this feature is dummied
out.  Henceforth, if gettimeofday's "struct timezone" argument is not
NULL, it will write zeroes to both fields.  Any program that is
actually looking at this data will thus think it is running in UTC,
which is probably more correct than whatever it was doing before.

[__]gettimeofday no longer has any internal callers, so we can now
remove its internal prototype and PLT bypass aliases.  The
__gettimeofday@GLIBC_2.0 export remains, in case it is used by any
third-party code.

It also allows to simplify the arch-specific implementation on x86 and
powerpc to remove the hack to disable the internal route to non iFUNC
variant for internal symbol.

This patch also fixes a missing optimization on aarch64, powerpc, and
x86 where the code used on static build do not use the vDSO.

Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu.

Co-authored-by: Zack Weinberg <zackw@panix.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
2019-10-30 17:11:10 -03:00
Adhemerval Zanella
b8a7c7da4e Refactor vDSO initialization code
Linux vDSO initialization code the internal function pointers require a
lot of duplicated boilerplate over different architectures.  This patch
aims to simplify not only the code but the required definition to enable
a vDSO symbol.

The changes are:

  1. Consolidate all init-first.c on only one implementation and enable
     the symbol based on HAVE_*_VSYSCALL existence.

  2. Set the HAVE_*_VSYSCALL to the architecture expected names string.

  3. Add a new internal implementation, get_vdso_mangle_symbol, which
     returns a mangled function pointer.

Currently the clock_gettime, clock_getres, gettimeofday, getcpu, and time
are handled in an arch-independent way, powerpc still uses some
arch-specific vDSO symbol handled in a specific init-first implementation.

Checked on aarch64-linux-gnu, arm-linux-gnueabihf, i386-linux-gnu,
mips64-linux-gnu, powerpc64le-linux-gnu, s390x-linux-gnu,
sparc64-linux-gnu, and x86_64-linux-gnu.

	* sysdeps/powerpc/powerpc32/backtrace.c (is_sigtramp_address,
	is_sigtramp_address_rt): Use HAVE_SIGTRAMP_{RT}32 instead of SHARED.
	* sysdeps/powerpc/powerpc64/backtrace.c (is_sigtramp_address):
	Likewise.
	* sysdeps/unix/sysv/linux/aarch64/init-first.c: Remove file.
	* sysdeps/unix/sysv/linux/aarch64/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/arm/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/i386/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/sparc/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Define value based on kernel exported
	name.
	* sysdeps/unix/sysv/linux/arm/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/i386/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETCPU_VSYSCALL, HAVE_TIME_VSYSCALL, HAVE_GET_TBFREQ,
	HAVE_SIGTRAMP_RT64, HAVE_SIGTRAMP_32, HAVE_SIGTRAMP_RT32i,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/riscv/sysdep.h (HAVE_CLOCK_GETRES_VSYSCALL,
	HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/s390/sysdep.h (HAVE_CLOCK_GETRES_VSYSCALL,
	HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/sparc/sysdep.h (HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL,
	HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/dl-vdso.h (VDSO_NAME, VDSO_HASH): Define to
	invalid names if architecture does not define them.
	(get_vdso_mangle_symbol): New symbol.
	* sysdeps/unix/sysv/linux/init-first.c: New file.
	* sysdeps/unix/sysv/linux/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/init-first.c (gettimeofday,
	clock_gettime, clock_getres, getcpu, time): Remove declaration.
	(__libc_vdso_platform_setup_arch): Likewise and use
	get_vdso_mangle_symbol to setup vDSO symbols.
	(sigtramp_rt64, sigtramp32, sigtramp_rt32, get_tbfreq): Add
	attribute_hidden.
	* sysdeps/unix/sysv/linux/powerpc/libc-vdso.h: Likewise.
	* sysdeps/unix/sysv/linux/sysdep-vdso.h (VDSO_SYMBOL): Remove
	definition.
2019-09-17 17:09:24 -03:00
Adhemerval Zanella
b8386c2859 Remove PREPARE_VERSION and PREPARE_VERSION_KNOW
This patch removes the PREPARE_VERSION and PREPARE_VERSION_KNOW macro
and uses a static inline function instead, get_vdso_symbol.  Each
architecture that supports vDSO must define the Linux version and its
hash for symbol resolution (VDSO_NAME and VDSO_HASH macro respectively).

It also organizes the HAVE_*_VSYSCALL for mips, powerpc, and s390 to
define them on a common header.

The idea is to require less code to configure and enable vDSO support
for newer ports.  No semantic changes are expected.

Checked with a build against all affected architectures.

	* sysdeps/unix/make-syscalls.sh: Make vDSO call use get_vdso_symbol.
	* sysdeps/unix/sysv/linux/aarch64/gettimeofday.c (__gettimeofday):
	Use get_vdso_symbol instead of _dl_vdso_vsym.
	* sysdeps/unix/sysv/linux/powerpc/time.c (time): Likewise.
	* sysdeps/unix/sysv/linux/riscv/flush-icache.c
	(__lookup_riscv_flush_icache): Likewise.
	* sysdeps/unix/sysv/linux/x86/gettimeofday.c (__gettimeofday):
	Likewise.
	* sysdeps/unix/sysv/linux/x86/time.c (time): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/gettimeofday.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/arm/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/riscv/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/sparc/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/sysdep.h (VDSO_NAME, VDSO_HASH):
	Define.
	* sysdeps/unix/sysv/linux/arm/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/i386/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/riscv/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/sparc/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/x86_64/sysdep.h (VDSO_NAME, VDSO_HASH):
	Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Remove
	definition.
	* sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
	(HAVE_CLOCK_GETTIME_VSYSCALL, HAVE_GETTIMEOFDAY_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL, HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h
	(HAVE_CLOCK_GETRES_VSYSCALL, HAVE_CLOCK_GETTIME_VSYSCALL,
	HAVE_GETTIMEOFDAY_VSYSCALL, HAVE_GETCPU_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/mips/sysdep.h: New file.
	* sysdeps/unix/sysv/linux/powerpc/sysdep.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/sysdep.h: Likewise.
	* sysdeps/unix/sysv/linux/dl-vdso.h (PREPARE_VERSION,
	PREPARE_VERSION_KNOWN, VDSO_NAME_LINUX_2_6, VDSO_HASH_LINUX_2_6,
	VDSO_NAME_LINUX_2_6_15, VDSO_HASH_LINUX_2_6_15,
	VDSO_NAME_LINUX_2_6_29, VDSO_HASH_LINUX_2_6_29,
	VDSO_NAME_LINUX_4_15, VDSO_HASH_LINUX_4_15): Remove defines.
	(get_vdso_symbol): New function.
2019-09-17 17:09:01 -03:00
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
Tobias Klauser
85c748f9ff Add missing VDSO_{NAME,HASH}_* macros and use them for PREPARE_VERSION_KNOWN
Define all currently used Linux versions used for
PREPARE_VERSION{,_KNOWN} in sysdeps/unix/sysv/linux/dl-vdso.h and use
them instead of duplicating the versions and precomputed hashes across
architecture specific files.

	* sysdeps/unix/sysv/linux/aarch64/gettimeofday.c (INIT_ARCH): Use
	PREPARE_VERSION_KNOWN.
	* sysdeps/unix/sysv/linux/aarch64/init-first.c: Likewise.
	* sysdeps/unix/sysv/linux/dl-vdso.h (VDSO_NAME_LINUX_2_6_39): New
	define.
	(VDSO_HASH_LINUX_2_6_39): Likewise.
	(VDSO_NAME_LINUX_4_9): Likewise.
	(VDSO_HASH_LINUX_4_9): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/gettimeofday.c (INIT_ARCH): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/init-first.c
	(_libc_vdso_platform_setup): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/time.c (INIT_ARCH): Likewise.
	* sysdeps/unix/sysv/linux/s390/init-first.c (_libc_vdso_platform_setup):
	Likewise.
	* sysdeps/unix/sysv/linux/x86_64/init-first.c (__vdso_platform_setup):
	Likewise.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-06-21 10:43:22 -03:00
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
Steve Ellcey
3c7b9f1fc3 aarch64: Use an ifunc/VDSO to implement gettimeofday in shared glibc.
This patch uses an ifunc to implement gettimeofday in the shared libc.
This is faster compared to the vsyscall mechanism that has to check a
global pointer, demangle it and call it indirectly when the VDSO is
present. Resolving the gettimeofday symbol directly to the VDSO code
is safe because there are no failures that the libc has to handle by
setting errno like in a generic vsyscall (the only failure when the
VDSO code falls back to a syscall is EFAULT, but passing an invalid
pointer is undefined behaviour so returning -EFAULT is fine).

If the kernel supports the VDSO interface we use it for extern calls,
otherwise the old vsyscall method is used which falls back to a syscall.
The static version of gettimeofday continues to use a syscall, libc.so
internal calls use the old vsyscall method.

	* sysdeps/unix/sysv/linux/aarch64/gettimeofday.c: New file.
2018-06-14 13:56:57 +01:00
Adhemerval Zanella
97554e4382 Consolidate gettimeofday across aarch64/s390/tile
This patch removes the architecture specific gettimeofday implementation
to use the vDSO symbol and consolidate it on a common Linux one.
Similar to clock_gettime and clock_getres vDSO implementation, each port
that supports gettimeofday through vDSO should just implement INLINE_VSYSCALL
to access the symbol and define HAVE_{GETTIME,GETRES}_VSYSCAL as 1.
2015-05-26 17:03:35 -03:00
Adhemerval Zanella
f534255e4d Consolidate vDSO macros and usage
This patch consolidate the Linux vDSO define and usage across all ports
that uses it.  The common vDSO definitions and calling through
{INLINE/INTERNAL}_VSYSCALL macros are moved to a common header
sysdep-vdso.h and vDSO name declaration and prototype is defined
using a common macro.

Also PTR_{MANGLE,DEMANGLE} is added to ports that does not use them
for vDSO calls (aarch64, powerpc, s390, and tile) and thus it will
reflect in code changes.  For ports that already implement pointer
mangling/demangling in vDSO system (i386, x32, x86_64) this patch
is mainly a code refactor.

Checked on x32, x86_64, x32, ppc64le, and aarch64.
2015-05-26 10:10:36 -03:00
Adhemerval Zanella
7bf8fb1042 libc-vdso.h place consolidation
This patch moves the libc-vdso.h internal header from bits folder to
default architecture one and also corrects the remaning includes in
the files.
2015-04-20 08:51:17 -03:00
Joseph Myers
b168057aaa Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
Marcus Shawcroft
75eff3fe90 Relocate AArch64 from ports to libc.
This patch moves the AArch64 port to the main sysdeps hierarchy.  The
move is essentially:

  git mv ports/sysdeps/aarch64 sysdeps/aarch64
  git mv ports/sysdeps/unix/sysv/linux/aarch64 sysdeps/unix/sysv/linux/aarch64

The README is updated and I've updated ChangeLog.aarch64 along the
lines of the ARM move.  The AArch64 build has been tested to confirm
that there were no changes in objdump -dr output or the shared
objects.
2014-02-11 11:36:00 +00:00