With the recent tuning the C version of rwlocks is basically the same
performance as the x86 assembler version for uncontended locks (with a
a few cycles near the run-to-run variability). For others it should not
matter anyways.
So remove the assembler code and use the C version like other
architectures.
This patch relies on the C version of the rwlocks posted earlier.
With C rwlocks it is very straight forward to do adaptive elision
using TSX. It is based on the infrastructure added earlier
for mutexes, but uses its own elision macros. The macros
are fairly general purpose and could be used for other
elision purposes too.
This version is much cleaner than the earlier assembler based
version, and in particular implements adaptation which makes
it safer.
I changed the behavior slightly to not require any changes
in the test suite and fully conform to all expected
behaviors (generally at the cost of not eliding in
various situations). In particular this means the timedlock
variants are not elided. Nested trylock aborts.
One difference of the C versions to the assembler wr/rdlock
is that the C compiler saves some registers which are unnecessary
for the fast path in the prologue of the functions. Split the
uncontended fast path out into a separate function. Only when contention is
detected is the full featured function called. This makes
the fast path code (nearly) identical to the assembler version,
and gives uncontended performance within a few cycles.
v2: Rename some functions and add space.
The implementation of __get_nprocs uses a stactic variable to cache
the value of the current number of processors. The caching breaks when
'time (NULL) == 0':
$ cat nproc.c
#include <stdio.h>
#include <time.h>
#include <sys/time.h>
int main(int argc, char *argv[])
{
time_t t;
struct timeval tv = {0, 0};
printf("settimeofday({0, 0}, NULL) = %d\n", settimeofday(&tv, NULL));
t = time(NULL);
printf("Time: %d, CPUs: %d\n", (unsigned int)t, get_nprocs());
return 0;
}
$ gcc -O3 nproc.c
$ ./a.out
settimeofday({0, 0}, NULL) = -1
Time: 1401311578, CPUs: 4
$ sudo ./a.out
settimeofday({0, 0}, NULL) = 0
Time: 0, CPUs: 0
The problem is with the condition used to check whether a cached
value should be returned or not:
static int cached_result;
static time_t timestamp;
time_t now = time (NULL);
time_t prev = timestamp;
atomic_read_barrier ();
if (now == prev)
return cached_result;
This patch fixes the problem by ensuring that 'cached_result' has
been set at least once before returning it.
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/mman.h, sys/stat.h
and sys/types.h. Tested x86_64; no new XFAILs needed.
* conform/data/sys/mman.h-data [POSIX] (size_t): Do not require
type.
[POSIX] (off_t): Likewise.
* conform/data/sys/stat.h-data (S_IRGRP): Require constant.
[POSIX] (S_ISBLK): Require macro.
[POSIX] (S_ISCHR): Likewise.
[POSIX] (S_ISDIR): Likewise.
[POSIX] (S_ISFIFO): Likewise.
[POSIX] (S_ISREG): Likewise.
[POSIX || XPG3 || XPG4 || UNIX98] (S_TYPEISTMO): Do not list
optional-macro.
* conform/data/sys/types.h-data [POSIX] (blkcnt_t): Do not require
type.
[POSIX] (time_t): Likewise.
[POSIX] (timer_t): Likewise.
POSIX requires that we make a copy, so we allocate a new string
and free it in posix_spawn_file_actions_destroy.
Reported by David Reid, Alex Gaynor, and Glyph Lefkowitz. This bug
may have security implications.
Optimization is achieved on 8 byte aligned strings with double word
comparison using cmpb instruction. On unaligned strings loop unrolling
is applied for Power7 gain.
As with other issues of this kind, bug 17042 is log2 (1) wrongly
returning -0 instead of +0 in round-downward mode because of
implementations effectively in terms of log1p (x - 1). This patch
fixes the issue in the same way used for log and log10.
Tested x86_64 and x86 and ulps updated accordingly. Also tested for
mips64 to confirm a fix was needed for ldbl-128 and to validate that
fix (also applied to ldbl-128ibm since that version of log2l is
essentially the same as the ldbl-128 one).
[BZ #17042]
* sysdeps/i386/fpu/e_log2.S (__ieee754_log2): Take absolete value
when x - 1 is zero.
* sysdeps/i386/fpu/e_log2f.S (__ieee754_log2f): Likewise.
* sysdeps/i386/fpu/e_log2l.S (__ieee754_log2l): Likewise.
* sysdeps/ieee754/ldbl-128/e_log2l.c (__ieee754_log2l): Return
0.0L for an argument of 1.0L.
* sysdeps/ieee754/ldbl-128ibm/e_log2l.c (__ieee754_log2l):
Likewise.
* sysdeps/x86_64/fpu/e_log2l.S (__ieee754_log2l): Take absolute
value when x - 1 is zero.
* math/libm-test.inc (log2_test): Use ALL_RM_TEST.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
The hppa port has no need of a custom lowlevellock.c, it should
use the generic version which is updated and correct. This
similarly fixes bug 15119 for hppa.
The localedata tests tst-mbswcs and tst-wctype use custom .sh scripts
and makefile rules, but have no need to do so. tst-mbswcs.sh runs a
series of test programs in succession (and nothing special is done
with the output of the programs); this patch makes the separate tests
into ordinary tests run directly by the usual makefile rules.
tst-wctype.sh runs one test with an environment variable and input
redirection; generic makefile rules also cover that, so again this
patch converts it into an ordinary test. (The makefile dependency of
tst-wctype.out on sort-test.out that this patch removes appears to be
a cut-and-paste error; the test does not appear to use that file.
There is already a generic dependency of ordinary tests in this
directory on $(addprefix $(objpfx),$(CTYPE_FILES)).)
Tested x86_64.
localedata/ChangeLog:
* Makefile (test-srcs): Remove tst-mbswcs1, tst-mbswcs2,
tst-mbswcs3, tst-mbswcs4, tst-mbswcs5 and tst-wctype.
(generated): Remove tst-mbswcs.out.
(tests): Add tst-mbswcs1, tst-mbswcs2, tst-mbswcs3, tst-mbswcs4,
tst-mbswcs5 and tst-wctype.
(tests-special): Remove $(objpfx)tst-mbswcs.out and
$(objpfx)tst-wctype.out.
($(objpfx)tst-mbswcs.out): Remove rule.
($(objpfx)tst-wctype.out): Likewise.
(tst-wctype-ENV): New variable.
* tst-mbswcs.sh: Remove file.
* tst-wctype.sh: Likewise.
Various glibc build / install / test code has C locale settings that
are redundant with LC_ALL=C.
LC_ALL takes precedence over LANG, so anywhere that sets LC_ALL=C
(explicitly, or through it being in the default environment for
running tests) does not need to set LANG=C. LC_ALL=C also takes
precedence over LANGUAGE, since
2001-01-02 Ulrich Drepper <drepper@redhat.com>
* intl/dcigettext.c (guess_category_value): Rewrite so that LANGUAGE
value is ignored if the selected locale is the C locale.
* intl/tst-gettext.c: Set locale for above change.
* intl/tst-translit.c: Likewise.
and so settings of LANGUAGE=C are also redundant when LC_ALL=C is
set. One test also had LC_ALL=C in its -ENV setting, although it's
part of the default environment used for tests.
This patch removes the redundant settings. It removes a suggestion in
install.texi of setting LANGUAGE=C LC_ALL=C for "make install"; the
Makefile.in target "install" already sets LC_ALL_C so there's no need
for the user to set it (and nor should there be any need for the user
to set it).
If some build machine tool used by "make install" uses a version of
libintl predating that 2001 change, and the user has LANGUAGE set, the
removal of LANGUAGE=C from the Makefile.in "install" rule could in
principle affect the user's installation. However, I don't think we
need to be concerned about pre-2001 build tools.
Tested x86_64.
* Makefile (install): Don't set LANGUAGE.
* Makefile.in (install): Likewise.
* assert/Makefile (test-assert-ENV): Remove variable.
(test-assert-perr-ENV): Likewise.
* elf/Makefile (neededtest4-ENV): Likewise.
* iconvdata/Makefile ($(inst_gconvdir)/gconv-modules)
[$(cross-compiling) = no]: Don't set LANGUAGE.
* io/ftwtest-sh (LANG): Remove variable.
* libio/Makefile (tst-widetext-ENV): Likewise.
* manual/install.texi (Running make install): Don't refer to
environment settings for make install.
* INSTALL: Regenerated.
* nptl/tst-tls6.sh: Don't set LANG.
* posix/globtest.sh (LANG): Remove variable.
* string/Makefile (tester-ENV): Likewise.
(inl-tester-ENV): Likewise.
(noinl-tester-ENV): Likewise.
* sysdeps/s390/s390-64/Makefile ($(inst_gconvdir)/gconv-modules)
[$(cross-compiling) = no]: Don't set LANGUAGE.
* timezone/Makefile (build-testdata): Use $(built-program-cmd)
without explicit environment settings.
localedata/ChangeLog:
* tst-fmon.sh: Don't set LANGUAGE.
* tst-locale.sh: Likewise.
The file has no inclusion guards, and contains typedefs that
cause errors when included multiple times with older (pre-C11)
compilers such as gcc 4.4.
Save the "#ifdef DOS" content to crypt-private.h even though
it's likely not particularly useful.
One wart in the original support for test wrappers for cross testing,
as noted in
<https://sourceware.org/ml/libc-alpha/2012-10/msg00722.html>, is the
requirement for test wrappers to pass a poorly-defined set of
environment variables from the build system to the system running the
glibc under test. Although some variables are passed explicitly via
$(test-wrapper-env), including LD_* variables that simply can't be
passed implicitly because of the side effects they'd have on the build
system's dynamic linker, others are passed implicitly, including
variables such as GCONV_PATH and LOCPATH that could potentially affect
the build system's libc (so effectively relying on any such effects
not breaking the wrappers). In addition, the code in
cross-test-ssh.sh for preserving environment variables is fragile (it
depends on how bash formats a list of exported variables, and could
well break for multi-line variable definitions where the contents
contain things looking like other variable definitions).
This patch moves to explicitly passing environment variables via
$(test-wrapper-env). Makefile variables that previously used
$(test-wrapper) are split up into -before-env and -after-env parts
that can be passed separately to the various .sh files used in
testing, so those files can then insert environment settings between
the two parts.
The common default environment settings in make-test-out are made into
a separate makefile variable that can also be passed to scripts,
rather than many scripts duplicating those settings (for testing an
installed glibc, it is desirable to have the GCONV_PATH setting on
just one place, so just that one place needs to support it pointing to
an installed sysroot instead of the build tree). The default settings
are included in the variables such as $(test-program-prefix), so that
if tests do not need any non-default settings they can continue to use
single variables rather than the split-up variables.
Although this patch cleans up LC_ALL=C settings (that being part of
the common defaults), various LANG=C and LANGUAGE=C settings remain.
Those are generally unnecessary and I propose a subsequent cleanup to
remove them. LC_ALL takes precedence over LANG, and while LANGUAGE
takes precedence over LC_ALL, it only does so for settings other than
LC_ALL=C. So LC_ALL=C on its own is sufficient to ensure the C
locale, and anything that gets LC_ALL=C does not need the other
settings.
While preparing this patch I noticed some tests with .sh files that
appeared to do nothing beyond what the generic makefile support for
tests can do (localedata/tst-wctype.sh - the makefiles support -ENV
variables and .input files - and localedata/tst-mbswcs.sh - just runs
five tests that could be run individually from the makefile). So I
propose another subsequent cleanup to move those to using the generic
support instead of special .sh files.
Tested x86_64 (native) and powerpc32 (cross).
* Makeconfig (run-program-env): New variable.
(run-program-prefix-before-env): Likewise.
(run-program-prefix-after-env): Likewise.
(run-program-prefix): Define in terms of new variables.
(built-program-cmd-before-env): New variable.
(built-program-cmd-after-env): Likewise.
(built-program-cmd): Define in terms of new variables.
(test-program-prefix-before-env): New variable.
(test-program-prefix-after-env): Likewise.
(test-program-prefix): Define in terms of new variables.
(test-program-cmd-before-env): New variable.
(test-program-cmd-after-env): Likewise.
(test-program-cmd): Define in terms of new variables.
* Rules (make-test-out): Use $(run-program-env).
* scripts/cross-test-ssh.sh (env_blacklist): Remove variable.
(help): Do not mention environment variables. Mention
--timeoutfactor option.
(timeoutfactor): New variable.
(blacklist_exports): Remove function.
(exports): Remove variable.
(command): Do not include ${exports}.
* manual/install.texi (Configuring and compiling): Do not mention
test wrappers preserving environment variables. Mention that last
assignment to a variable must take precedence.
* INSTALL: Regenerated.
* benchtests/Makefile (run-bench): Use $(run-program-env).
* catgets/Makefile ($(objpfx)test1.cat): Use
$(built-program-cmd-before-env), $(run-program-env) and
$(built-program-cmd-after-env).
($(objpfx)test2.cat): Do not specify environment variables
explicitly.
($(objpfx)de/libc.cat): Use $(built-program-cmd-before-env),
$(run-program-env) and $(built-program-cmd-after-env).
($(objpfx)test-gencat.out): Use $(test-program-cmd-before-env),
$(run-program-env) and $(test-program-cmd-after-env).
($(objpfx)sample.SJIS.cat): Do not specify environment variables
explicitly.
* catgets/test-gencat.sh: Use test_program_cmd_before_env,
run_program_env and test_program_cmd_after_env arguments.
* elf/Makefile ($(objpfx)tst-pathopt.out): Use $(run-program-env).
* elf/tst-pathopt.sh: Use run_program_env argument.
* iconvdata/Makefile ($(objpfx)iconv-test.out): Use
$(test-wrapper-env) and $(run-program-env).
* iconvdata/run-iconv-test.sh: Use test_wrapper_env and
run_program_env arguments.
* iconvdata/tst-table.sh: Do not set GCONV_PATH explicitly.
* intl/Makefile ($(objpfx)tst-gettext.out): Use
$(test-program-prefix-before-env), $(run-program-env) and
$(test-program-prefix-after-env).
($(objpfx)tst-gettext2.out): Likewise.
* intl/tst-gettext.sh: Use test_program_prefix_before_env,
run_program_env and test_program_prefix_after_env arguments.
* intl/tst-gettext2.sh: Likewise.
* intl/tst-gettext4.sh: Do not set environment variables
explicitly.
* intl/tst-gettext6.sh: Likewise.
* intl/tst-translit.sh: Likewise.
* malloc/Makefile ($(objpfx)tst-mtrace.out): Use
$(test-program-prefix-before-env), $(run-program-env) and
$(test-program-prefix-after-env).
* malloc/tst-mtrace.sh: Use test_program_prefix_before_env,
run_program_env and test_program_prefix_after_env arguments.
* math/Makefile (run-regen-ulps): Use $(run-program-env).
* nptl/Makefile ($(objpfx)tst-tls6.out): Use $(run-program-env).
* nptl/tst-tls6.sh: Use run_program_env argument. Set LANG=C
explicitly with each use of ${test_wrapper_env}.
* posix/Makefile ($(objpfx)wordexp-tst.out): Use
$(test-program-prefix-before-env), $(run-program-env) and
$(test-program-prefix-after-env).
* posix/tst-getconf.sh: Do not set environment variables
explicitly.
* posix/wordexp-tst.sh: Use test_program_prefix_before_env,
run_program_env and test_program_prefix_after_env arguments.
* stdio-common/tst-printf.sh: Do not set environment variables
explicitly.
* stdlib/Makefile ($(objpfx)tst-fmtmsg.out): Use
$(test-program-prefix-before-env), $(run-program-env) and
$(test-program-prefix-after-env).
* stdlib/tst-fmtmsg.sh: Use test_program_prefix_before_env,
run_program_env and test_program_prefix_after_env arguments.
Split $test calls into $test_pre and $test.
* timezone/Makefile (build-testdata): Use
$(built-program-cmd-before-env), $(run-program-env) and
$(built-program-cmd-after-env).
localedata/ChangeLog:
* Makefile ($(addprefix $(objpfx),$(CTYPE_FILES))): Use
$(built-program-cmd-before-env), $(run-program-env) and
$(built-program-cmd-after-env).
($(objpfx)sort-test.out): Use $(test-program-prefix-before-env),
$(run-program-env) and $(test-program-prefix-after-env).
($(objpfx)tst-fmon.out): Use $(run-program-prefix-before-env),
$(run-program-env) and $(run-program-prefix-after-env).
($(objpfx)tst-locale.out): Use $(built-program-cmd-before-env),
$(run-program-env) and $(built-program-cmd-after-env).
($(objpfx)tst-trans.out): Use $(run-program-prefix-before-env),
$(run-program-env), $(run-program-prefix-after-env),
$(test-program-prefix-before-env) and
$(test-program-prefix-after-env).
($(objpfx)tst-ctype.out): Use $(test-program-cmd-before-env),
$(run-program-env) and $(test-program-cmd-after-env).
($(objpfx)tst-wctype.out): Likewise.
($(objpfx)tst-langinfo.out): Likewise.
($(objpfx)tst-langinfo-static.out): Likewise.
* gen-locale.sh: Use localedef_before_env, run_program_env and
localedef_after_env arguments.
* sort-test.sh: Use test_program_prefix_before_env,
run_program_env and test_program_prefix_after_env arguments.
* tst-ctype.sh: Use tst_ctype_before_env, run_program_env and
tst_ctype_after_env arguments.
* tst-fmon.sh: Use run_program_prefix_before_env, run_program_env
and run_program_prefix_after_env arguments.
* tst-langinfo.sh: Use tst_langinfo_before_env, run_program_env
and tst_langinfo_after_env arguments.
* tst-locale.sh: Use localedef_before_env, run_program_env and
localedef_after_env arguments.
* tst-mbswcs.sh: Do not set environment variables explicitly.
* tst-numeric.sh: Likewise.
* tst-rpmatch.sh: Likewise.
* tst-trans.sh: Use run_program_prefix_before_env,
run_program_env, run_program_prefix_after_env,
test_program_prefix_before_env and test_program_prefix_after_env
arguments.
* tst-wctype.sh: Use tst_wctype_before_env, run_program_env and
tst_wctype_after_env arguments.
