The TUNABLE_SET_VALUE and family of macros (and my later attempt to
add a TUNABLE_GET) never quite went together very well because the
overall interface was not clearly defined. This patch is an attempt
to do just that.
This patch consolidates the API to two simple sets of macros,
TUNABLE_GET* and TUNABLE_SET*. If TUNABLE_NAMESPACE is defined,
TUNABLE_GET takes just the tunable name, type and a (optionally NULL)
callback function to get the value of the tunable. The callback
function, if non-NULL, is called if the tunable was externally set
(i.e. via GLIBC_TUNABLES or any future mechanism). For example:
val = TUNABLE_GET (check, int32_t, check_callback)
returns the value of the glibc.malloc.check tunable (assuming
TUNABLE_NAMESPACE is set to malloc) as an int32_t into VAL after
calling check_callback.
Likewise, TUNABLE_SET can be used to set the value of the tunable,
although this is currently possible only in the dynamic linker before
it relocates itself. For example:
TUNABLE_SET (check, int32_t, 2)
will set glibc.malloc.check to 2. Of course, this is not possible
since we set (or read) glibc.malloc.check long after it is relocated.
To access or set a tunable outside of TUNABLE_NAMESPACE, use the
TUNABLE_GET_FULL and TUNABLE_SET_FULL macros, which have the following
prototype:
TUNABLE_GET_FULL (glibc, tune, hwcap_mask, uint64_t, NULL)
TUNABLE_SET_FULL (glibc, tune, hwcap_mask, uint64_t, 0xffff)
In future the tunable list may get split into mutable and immutable
tunables where mutable tunables can be modified by the library and
userspace after relocation as well and TUNABLE_SET will be more useful
than it currently is. However whenever we actually do that split, we
will have to ensure that the mutable tunables are protected with
locks.
* elf/Versions (__tunable_set_val): Rename to __tunable_get_val.
* elf/dl-tunables.c: Likewise.
(do_tunable_update_val): New function.
(__tunable_set_val): New function.
(__tunable_get_val): Call CB only if the tunable was externally
initialized.
(tunables_strtoul): Replace strval with initialized.
* elf/dl-tunables.h (strval): Replace with a bool initialized.
(TUNABLE_ENUM_NAME, TUNABLE_ENUM_NAME1): Adjust names to
prevent collision.
(__tunable_set_val): New function.
(TUNABLE_GET, TUNABLE_GET_FULL): New macros.
(TUNABLE_SET, TUNABLE_SET_FULL): Likewise.
(TUNABLE_SET_VAL): Remove.
(TUNABLE_SET_VAL_WITH_CALLBACK): Likewise.
* README.tunables: Document the new macros.
* malloc/arena.c (ptmalloc_init): Adjust.
This is intended as a type-safe alternative to obstacks and
hand-written realloc constructs. The implementation avoids
writing function pointers to the heap.
This patch adds a new build module called 'testsuite'.
IS_IN (testsuite) implies _ISOMAC, as do IS_IN_build and __cplusplus
(which means several ad-hoc tests for __cplusplus can go away).
libc-symbols.h now suppresses almost all of *itself* when _ISOMAC is
defined; in particular, _ISOMAC mode does not get config.h
automatically anymore.
There are still quite a few tests that need to see internal gunk of
one variety or another. For them, we now have 'tests-internal' and
'test-internal-extras'; files in this category will still be compiled
with MODULE_NAME=nonlib, and everything proceeds as it always has.
The bulk of this patch is moving tests from 'tests' to
'tests-internal'. There is also 'tests-static-internal', which has
the same effect on files in 'tests-static', and 'modules-names-tests',
which has the *inverse* effect on files in 'modules-names' (it's
inverted because most of the things in modules-names are *not* tests).
For both of these, the file must appear in *both* the new variable and
the old one.
There is also now a special case for when libc-symbols.h is included
without MODULE_NAME being defined at all. (This happens during the
creation of libc-modules.h, and also when preprocessing Versions
files.) When this happens, IS_IN is set to be always false and
_ISOMAC is *not* defined, which was the status quo, but now it's
explicit.
The remaining changes to C source files in this patch seemed likely to
cause problems in the absence of the main change. They should be
relatively self-explanatory. In a few cases I duplicated a definition
from an internal header rather than move the test to tests-internal;
this was a judgement call each time and I'm happy to change those
however reviewers feel is more appropriate.
* Makerules: New subdir configuration variables 'tests-internal'
and 'test-internal-extras'. Test files in these categories will
still be compiled with MODULE_NAME=nonlib. Test files in the
existing categories (tests, xtests, test-srcs, test-extras) are
now compiled with MODULE_NAME=testsuite.
New subdir configuration variable 'modules-names-tests'. Files
which are in both 'modules-names' and 'modules-names-tests' will
be compiled with MODULE_NAME=testsuite instead of
MODULE_NAME=extramodules.
(gen-as-const-headers): Move to tests-internal.
(do-tests-clean, common-mostlyclean): Support tests-internal.
* Makeconfig (built-modules): Add testsuite.
* Makefile: Change libof-check-installed-headers-c and
libof-check-installed-headers-cxx to 'testsuite'.
* Rules: Likewise. Support tests-internal.
* benchtests/strcoll-inputs/filelist#en_US.UTF-8:
Remove extra-modules.mk.
* config.h.in: Don't check for __OPTIMIZE__ or __FAST_MATH__ here.
* include/libc-symbols.h: Move definitions of _GNU_SOURCE,
PASTE_NAME, PASTE_NAME1, IN_MODULE, IS_IN, and IS_IN_LIB to the
very top of the file and rationalize their order.
If MODULE_NAME is not defined at all, define IS_IN to always be
false, and don't define _ISOMAC.
If any of IS_IN (testsuite), IS_IN_build, or __cplusplus are
true, define _ISOMAC and suppress everything else in this file,
starting with the inclusion of config.h.
Do check for inappropriate definitions of __OPTIMIZE__ and
__FAST_MATH__ here, but only if _ISOMAC is not defined.
Correct some out-of-date commentary.
* include/math.h: If _ISOMAC is defined, undefine NO_LONG_DOUBLE
and _Mlong_double_ before including math.h.
* include/string.h: If _ISOMAC is defined, don't expose
_STRING_ARCH_unaligned. Move a comment to a more appropriate
location.
* include/errno.h, include/stdio.h, include/stdlib.h, include/string.h
* include/time.h, include/unistd.h, include/wchar.h: No need to
check __cplusplus nor use __BEGIN_DECLS/__END_DECLS.
* misc/sys/cdefs.h (__NTHNL): New macro.
* sysdeps/m68k/m680x0/fpu/bits/mathinline.h
(__m81_defun): Use __NTHNL to avoid errors with GCC 6.
* elf/tst-env-setuid-tunables.c: Include config.h with _LIBC
defined, for HAVE_TUNABLES.
* inet/tst-checks-posix.c: No need to define _ISOMAC.
* intl/tst-gettext2.c: Provide own definition of N_.
* math/test-signgam-finite-c99.c: No need to define _ISOMAC.
* math/test-signgam-main.c: No need to define _ISOMAC.
* stdlib/tst-strtod.c: Convert to test-driver. Split locale_test to...
* stdlib/tst-strtod1i.c: ...this new file.
* stdlib/tst-strtod5.c: Convert to test-driver and add copyright notice.
Split tests of __strtod_internal to...
* stdlib/tst-strtod5i.c: ...this new file.
* string/test-string.h: Include stdint.h. Duplicate definition of
inhibit_loop_to_libcall here (from libc-symbols.h).
* string/test-strstr.c: Provide dummy definition of
libc_hidden_builtin_def when including strstr.c.
* sysdeps/ia64/fpu/libm-symbols.h: Suppress entire file in _ISOMAC
mode; no need to test __STRICT_ANSI__ nor __cplusplus as well.
* sysdeps/x86_64/fpu/math-tests-arch.h: Include cpu-features.h.
Don't include init-arch.h.
* sysdeps/x86_64/multiarch/test-multiarch.h: Include cpu-features.h.
Don't include init-arch.h.
* elf/Makefile: Move tst-ptrguard1-static, tst-stackguard1-static,
tst-tls1-static, tst-tls2-static, tst-tls3-static, loadtest,
unload, unload2, circleload1, neededtest, neededtest2,
neededtest3, neededtest4, tst-tls1, tst-tls2, tst-tls3,
tst-tls6, tst-tls7, tst-tls8, tst-dlmopen2, tst-ptrguard1,
tst-stackguard1, tst-_dl_addr_inside_object, and all of the
ifunc tests to tests-internal.
Don't add $(modules-names) to test-extras.
* inet/Makefile: Move tst-inet6_scopeid_pton to tests-internal.
Add tst-deadline to tests-static-internal.
* malloc/Makefile: Move tst-mallocstate and tst-scratch_buffer to
tests-internal.
* misc/Makefile: Move tst-atomic and tst-atomic-long to tests-internal.
* nptl/Makefile: Move tst-typesizes, tst-rwlock19, tst-sem11,
tst-sem12, tst-sem13, tst-barrier5, tst-signal7, tst-tls3,
tst-tls3-malloc, tst-tls5, tst-stackguard1, tst-sem11-static,
tst-sem12-static, and tst-stackguard1-static to tests-internal.
Link tests-internal with libpthread also.
Don't add $(modules-names) to test-extras.
* nss/Makefile: Move tst-field to tests-internal.
* posix/Makefile: Move bug-regex5, bug-regex20, bug-regex33,
tst-rfc3484, tst-rfc3484-2, and tst-rfc3484-3 to tests-internal.
* stdlib/Makefile: Move tst-strtod1i, tst-strtod3, tst-strtod4,
tst-strtod5i, tst-tls-atexit, and tst-tls-atexit-nodelete to
tests-internal.
* sunrpc/Makefile: Move tst-svc_register to tests-internal.
* sysdeps/powerpc/Makefile: Move test-get_hwcap and
test-get_hwcap-static to tests-internal.
* sysdeps/unix/sysv/linux/Makefile: Move tst-setgetname to
tests-internal.
* sysdeps/x86_64/fpu/Makefile: Add all libmvec test modules to
modules-names-tests.
cppflags-iterator.mk no longer has anything to do with CPPFLAGS; all
it does is set libof-$(foo) for a list of files. extra-modules.mk
does the same thing, but with a different input variable, and doesn't
let the caller control the module. Therefore, this patch gives
cppflags-iterator.mk a better name, removes extra-modules.mk, and
updates all uses of both.
* extra-modules.mk: Delete file.
* cppflags-iterator.mk: Rename to ...
* libof-iterator.mk: ...this. Adjust comments.
* Makerules, extra-lib.mk, benchtests/Makefile, elf/Makefile
* elf/rtld-Rules, iconv/Makefile, locale/Makefile, malloc/Makefile
* nscd/Makefile, sunrpc/Makefile, sysdeps/s390/Makefile:
Use libof-iterator.mk instead of cppflags-iterator.mk or
extra-modules.mk.
* benchtests/strcoll-inputs/filelist#en_US.UTF-8: Remove
extra-modules.mk and cppflags-iterator.mk, add libof-iterator.mk.
MMap'd memory isn't shrunk without MREMAP, but IIRC this is intentional for
performance reasons. Regardless, this patch tweaks the existing comment to
be more accurate wrt the existing code.
[BZ #21411]
* malloc/malloc.c: Tweak realloc/MREMAP comment to be more accurate.
Fixes a typo introduced in commit
be7991c070. This caused
mallopt(M_ARENA_MAX) as well as the environment variable
MALLOC_ARENA_MAX to not work as intended because it set the
wrong internal parameter.
[BZ #21338]
* malloc/malloc.c: Call do_set_arena_max for M_ARENA_MAX
instead of incorrect do_set_arena_test
The test malloc/tst-interpose-nothread fails on s390x if built
with GCC 7 and glibc commit "Remove the str(n)dup inlines
from string/bits/string2.h. Although inlining"
(ae65d4f3c3) with output:
error: free: 0x3fffdffa010: invalid allocation index: 0 (not less than 0)
The destructor check_for_allocations in malloc/tst-interpose-aux.c is
called twice. One time after the test-child-process has finished successfully
and once after the test-parent-process finishes.
During the latter invocation, allocation_index == 0. GCC 7 is now inlining the
free function and calls unconditionally fail in get_header as
header->allocation_index (type == size_t) is always >= allocation_index (= 0).
Before the mentioned commit above, strdup was replaced by strlen, malloc and
memcpy. The malloc call was also inlined and allocation_index was set to one.
This patch moves the already existing compiler barrier before the invocation
of free.
ChangeLog:
* malloc/tst-interpose-aux.c (check_for_allocations):
Move compiler barrier before free.
Additional check for chunk_size == next->prev->chunk_size in unlink()
2017-03-17 Chris Evans <scarybeasts@gmail.com>
* malloc/malloc.c (unlink): Add consistency check between size and
next->prev->size, to further harden against 1-byte overflows.
posix/wordexp-test.c used libc-internal.h for PTR_ALIGN_DOWN; similar
to what was done with libc-diag.h, I have split the definitions of
cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN
to a new header, libc-pointer-arith.h.
It then occurred to me that the remaining declarations in libc-internal.h
are mostly to do with early initialization, and probably most of the
files including it, even in the core code, don't need it anymore. Indeed,
only 19 files actually need what remains of libc-internal.h. 23 others
need libc-diag.h instead, and 12 need libc-pointer-arith.h instead.
No file needs more than one of them, and 16 don't need any of them!
So, with this patch, libc-internal.h stops including libc-diag.h as
well as losing the pointer arithmetic macros, and all including files
are adjusted.
* include/libc-pointer-arith.h: New file. Define
cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and
PTR_ALIGN_DOWN here.
* include/libc-internal.h: Definitions of above macros
moved from here. Don't include libc-diag.h anymore either.
* posix/wordexp-test.c: Include stdint.h and libc-pointer-arith.h.
Don't include libc-internal.h.
* debug/pcprofile.c, elf/dl-tunables.c, elf/soinit.c, io/openat.c
* io/openat64.c, misc/ptrace.c, nptl/pthread_clock_gettime.c
* nptl/pthread_clock_settime.c, nptl/pthread_cond_common.c
* string/strcoll_l.c, sysdeps/nacl/brk.c
* sysdeps/unix/clock_settime.c
* sysdeps/unix/sysv/linux/i386/get_clockfreq.c
* sysdeps/unix/sysv/linux/ia64/get_clockfreq.c
* sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c
* sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c:
Don't include libc-internal.h.
* elf/get-dynamic-info.h, iconv/loop.c
* iconvdata/iso-2022-cn-ext.c, locale/weight.h, locale/weightwc.h
* misc/reboot.c, nis/nis_table.c, nptl_db/thread_dbP.h
* nscd/connections.c, resolv/res_send.c, soft-fp/fmadf4.c
* soft-fp/fmasf4.c, soft-fp/fmatf4.c, stdio-common/vfscanf.c
* sysdeps/ieee754/dbl-64/e_lgamma_r.c
* sysdeps/ieee754/dbl-64/k_rem_pio2.c
* sysdeps/ieee754/flt-32/e_lgammaf_r.c
* sysdeps/ieee754/flt-32/k_rem_pio2f.c
* sysdeps/ieee754/ldbl-128/k_tanl.c
* sysdeps/ieee754/ldbl-128ibm/k_tanl.c
* sysdeps/ieee754/ldbl-96/e_lgammal_r.c
* sysdeps/ieee754/ldbl-96/k_tanl.c, sysdeps/nptl/futex-internal.h:
Include libc-diag.h instead of libc-internal.h.
* elf/dl-load.c, elf/dl-reloc.c, locale/programs/locarchive.c
* nptl/nptl-init.c, string/strcspn.c, string/strspn.c
* malloc/malloc.c, sysdeps/i386/nptl/tls.h
* sysdeps/nacl/dl-map-segments.h, sysdeps/x86_64/atomic-machine.h
* sysdeps/unix/sysv/linux/spawni.c
* sysdeps/x86_64/nptl/tls.h:
Include libc-pointer-arith.h instead of libc-internal.h.
* elf/get-dynamic-info.h, sysdeps/nacl/dl-map-segments.h
* sysdeps/x86_64/atomic-machine.h:
Add multiple include guard.
Quite a few tests include libc-internal.h just for the DIAG_* macros.
Split those macros to their own file, which can be included safely in
_ISOMAC mode. I also moved ignore_value, since it seems logically
related, even though I didn't notice any tests needing it.
Also add -Wnonnull suppressions to two tests that _should_ have them,
but the error is masked when compiling against internal headers.
* include/libc-diag.h: New file. Define ignore_value,
DIAG_PUSH_NEEDS_COMMENT, DIAG_POP_NEEDS_COMMENT,
DIAG_IGNORE_NEEDS_COMMENT, and DIAG_IGNORE_Os_NEEDS_COMMENT here.
* include/libc-internal.h: Definitions of above macros moved from
here. Include libc-diag.h. Add copyright notice.
* malloc/tst-malloc.c, malloc/tst-memcheck.c, malloc/tst-realloc.c
* misc/tst-error1.c, posix/tst-dir.c, stdio-common/bug21.c
* stdio-common/scanf14.c, stdio-common/scanf4.c, stdio-common/scanf7.c
* stdio-common/test-vfprintf.c, stdio-common/tst-printf.c
* stdio-common/tst-printfsz.c, stdio-common/tst-sprintf.c
* stdio-common/tst-unlockedio.c, stdio-common/tstdiomisc.c
* stdlib/bug-getcontext.c, string/tester.c, string/tst-endian.c
* time/tst-strptime2.c, wcsmbs/tst-wcstof.c:
Include libc-diag.h instead of libc-internal.h.
* stdlib/tst-environ.c: Include libc-diag.h. Suppress -Wnonnull for
call to unsetenv (NULL).
* nptl/tst-mutex1.c: Include libc-diag.h. Suppress -Wnonnull for
call to pthread_mutexattr_destroy (NULL).
* crypt/md5.h: Test _LIBC with #if defined, not #if.
* dirent/opendir-tst1.c: Include sys/stat.h.
* dirent/tst-fdopendir.c: Include sys/stat.h.
* dirent/tst-fdopendir2.c: Include stdlib.h.
* dirent/tst-scandir.c: Include stdbool.h.
* elf/tst-auditmod1.c: Include link.h and stddef.h.
* elf/tst-tls15.c: Include stdlib.h.
* elf/tst-tls16.c: Include stdlib.h.
* elf/tst-tls17.c: Include stdlib.h.
* elf/tst-tls18.c: Include stdlib.h.
* iconv/tst-iconv6.c: Include endian.h.
* iconvdata/bug-iconv11.c: Include limits.h.
* io/test-utime.c: Include stdint.h.
* io/tst-faccessat.c: Include sys/stat.h.
* io/tst-fchmodat.c: Include sys/stat.h.
* io/tst-fchownat.c: Include sys/stat.h.
* io/tst-fstatat.c: Include sys/stat.h.
* io/tst-futimesat.c: Include sys/stat.h.
* io/tst-linkat.c: Include sys/stat.h.
* io/tst-mkdirat.c: Include sys/stat.h and stdbool.h.
* io/tst-mkfifoat.c: Include sys/stat.h and stdbool.h.
* io/tst-mknodat.c: Include sys/stat.h and stdbool.h.
* io/tst-openat.c: Include stdbool.h.
* io/tst-readlinkat.c: Include sys/stat.h.
* io/tst-renameat.c: Include sys/stat.h.
* io/tst-symlinkat.c: Include sys/stat.h.
* io/tst-unlinkat.c: Include stdbool.h.
* libio/bug-memstream1.c: Include stdlib.h.
* libio/bug-wmemstream1.c: Include stdlib.h.
* libio/tst-fwrite-error.c: Include stdlib.h.
* libio/tst-memstream1.c: Include stdlib.h.
* libio/tst-memstream2.c: Include stdlib.h.
* libio/tst-memstream3.c: Include stdlib.h.
* malloc/tst-interpose-aux.c: Include stdint.h.
* misc/tst-preadvwritev-common.c: Include sys/stat.h.
* nptl/tst-basic7.c: Include limits.h.
* nptl/tst-cancel25.c: Include pthread.h, not pthreadP.h.
* nptl/tst-cancel4.c: Include stddef.h, limits.h, and sys/stat.h.
* nptl/tst-cancel4_1.c: Include stddef.h.
* nptl/tst-cancel4_2.c: Include stddef.h.
* nptl/tst-cond16.c: Include limits.h.
Use sysconf(_SC_PAGESIZE) instead of __getpagesize.
* nptl/tst-cond18.c: Include limits.h.
Use sysconf(_SC_PAGESIZE) instead of __getpagesize.
* nptl/tst-cond4.c: Include stdint.h.
* nptl/tst-cond6.c: Include stdint.h.
* nptl/tst-stack2.c: Include limits.h.
* nptl/tst-stackguard1.c: Include stddef.h.
* nptl/tst-tls4.c: Include stdint.h. Don't include tls.h.
* nptl/tst-tls4moda.c: Include stddef.h.
Don't include stdio.h, unistd.h, or tls.h.
* nptl/tst-tls4modb.c: Include stddef.h.
Don't include stdio.h, unistd.h, or tls.h.
* nptl/tst-tls5.h: Include stddef.h. Don't include stdlib.h or tls.h.
* posix/tst-getaddrinfo2.c: Include stdio.h.
* posix/tst-getaddrinfo5.c: Include stdio.h.
* posix/tst-pathconf.c: Include sys/stat.h.
* posix/tst-posix_fadvise-common.c: Include stdint.h.
* posix/tst-preadwrite-common.c: Include sys/stat.h.
* posix/tst-regex.c: Include stdint.h.
Don't include spawn.h or spawn_int.h.
* posix/tst-regexloc.c: Don't include spawn.h or spawn_int.h.
* posix/tst-vfork3.c: Include sys/stat.h.
* resolv/tst-bug18665-tcp.c: Include stdlib.h.
* resolv/tst-res_hconf_reorder.c: Include stdlib.h.
* resolv/tst-resolv-search.c: Include stdlib.h.
* stdio-common/tst-fmemopen2.c: Include stdint.h.
* stdio-common/tst-vfprintf-width-prec.c: Include stdlib.h.
* stdlib/test-canon.c: Include sys/stat.h.
* stdlib/tst-tls-atexit.c: Include stdbool.h.
* string/test-memchr.c: Include stdint.h.
* string/tst-cmp.c: Include stdint.h.
* sysdeps/pthread/tst-timer.c: Include stdint.h.
* sysdeps/unix/sysv/linux/tst-sync_file_range.c: Include stdint.h.
* sysdeps/wordsize-64/tst-writev.c: Include limits.h and stdint.h.
* sysdeps/x86_64/fpu/math-tests-arch.h: Include cpu-features.h.
Don't include init-arch.h.
* sysdeps/x86_64/multiarch/test-multiarch.h: Include cpu-features.h.
Don't include init-arch.h.
* sysdeps/x86_64/tst-auditmod10b.c: Include link.h and stddef.h.
* sysdeps/x86_64/tst-auditmod3b.c: Include link.h and stddef.h.
* sysdeps/x86_64/tst-auditmod4b.c: Include link.h and stddef.h.
* sysdeps/x86_64/tst-auditmod5b.c: Include link.h and stddef.h.
* sysdeps/x86_64/tst-auditmod6b.c: Include link.h and stddef.h.
* sysdeps/x86_64/tst-auditmod6c.c: Include link.h and stddef.h.
* sysdeps/x86_64/tst-auditmod7b.c: Include link.h and stddef.h.
* time/clocktest.c: Include stdint.h.
* time/tst-posixtz.c: Include stdint.h.
* timezone/tst-timezone.c: Include stdint.h.
The code to set value passed a tunable_val_t, which when cast to
int32_t on big-endian gives the wrong value. Instead, use
tunable_val_t.numval instead, which can then be safely cast into
int32_t.
This patch increases timeouts on some tests I've observed timing out.
elf/tst-tls13 and iconvdata/tst-loading both dynamically load many
objects and so are slow when testing over NFS. They had timeouts set
from before the default changed from 2 to 20 seconds; this patch
removes those old settings, so effectively increasing the timeout to
20 seconds (from 3 and 10 seconds respectively).
malloc/tst-malloc-thread-fail.c and malloc/tst-mallocfork2.c are slow
on slow systems and so I set a fairly arbitrary 100 second timeout,
which seems to suffice on the system where I saw them timing out.
nss/tst-cancel-getpwuid_r.c and nss/tst-nss-getpwent.c are slow on
systems with a large passwd file; I set timeouts that empirically
worked for me. (It seems tst-cancel-getpwuid_r.c is hitting the
100000 getpwuid_r call limit in my testing, with each call taking a
bit over 0.007 seconds, so 700 seconds for the test.)
* elf/tst-tls13.c (TIMEOUT): Remove.
* iconvdata/tst-loading.c (TIMEOUT): Likewise.
* malloc/tst-malloc-thread-fail.c (TIMEOUT): Increase to 100.
* malloc/tst-mallocfork2.c (TIMEOUT): Define to 100.
* nss/tst-cancel-getpwuid_r.c (TIMEOUT): Define to 900.
* nss/tst-nss-getpwent.c (TIMEOUT): Define to 300.
GCC 7 has a -Walloc-size-larger-than= warning for allocations of half
the address space or more. This causes errors building glibc tests
that deliberately test failure of very large allocations. This patch
arranges for this warning to be ignored around the problematic
function calls.
Tested compilation for aarch64 (GCC mainline) with
build-many-glibcs.py; did execution testing for x86_64 (GCC 5).
* malloc/tst-malloc.c: Include <libc-internal.h>.
(do_test): Disable -Walloc-size-larger-than= around tests of
malloc with negative sizes.
* malloc/tst-mcheck.c: Include <libc-internal.h>.
(do_test): Disable -Walloc-size-larger-than= around tests of
malloc and realloc with negative sizes.
* malloc/tst-realloc.c: Include <libc-internal.h>.
(do_test): Disable -Walloc-size-larger-than= around tests of
realloc with negative sizes.
Read tunables values from the users using the GLIBC_TUNABLES
environment variable. The value of this variable is a colon-separated
list of name=value pairs. So a typical string would look like this:
GLIBC_TUNABLES=glibc.malloc.mmap_threshold=2048:glibc.malloc.trim_threshold=1024
* config.make.in (have-loop-to-function): Define.
* elf/Makefile (CFLAGS-dl-tunables.c): Add
-fno-tree-loop-distribute-patterns.
* elf/dl-tunables.c: Include libc-internals.h.
(GLIBC_TUNABLES): New macro.
(tunables_strdup): New function.
(parse_tunables): New function.
(min_strlen): New function.
(__tunables_init): Use the new functions and macro.
(disable_tunable): Disable tunable from GLIBC_TUNABLES.
* malloc/tst-malloc-usable-tunables.c: New test case.
* malloc/tst-malloc-usable-static-tunables.c: New test case.
* malloc/Makefile (tests, tests-static): Add tests.
The tunables framework allows us to uniformly manage and expose global
variables inside glibc as switches to users. tunables/README has
instructions for glibc developers to add new tunables.
Tunables support can be enabled by passing the --enable-tunables
configure flag to the configure script. This patch only adds a
framework and does not pose any limitations on how tunable values are
read from the user. It also adds environment variables used in malloc
behaviour tweaking to the tunables framework as a PoC of the
compatibility interface.
* manual/install.texi: Add --enable-tunables option.
* INSTALL: Regenerate.
* README.tunables: New file.
* Makeconfig (CPPFLAGS): Define TOP_NAMESPACE.
(before-compile): Generate dl-tunable-list.h early.
* config.h.in: Add HAVE_TUNABLES.
* config.make.in: Add have-tunables.
* configure.ac: Add --enable-tunables option.
* configure: Regenerate.
* csu/init-first.c (__libc_init_first): Move
__libc_init_secure earlier...
* csu/init-first.c (LIBC_START_MAIN):... to here.
Include dl-tunables.h, libc-internal.h.
(LIBC_START_MAIN) [!SHARED]: Initialize tunables for static
binaries.
* elf/Makefile (dl-routines): Add dl-tunables.
* elf/Versions (ld): Add __tunable_set_val to GLIBC_PRIVATE
namespace.
* elf/dl-support (_dl_nondynamic_init): Unset MALLOC_CHECK_
only when !HAVE_TUNABLES.
* elf/rtld.c (process_envvars): Likewise.
* elf/dl-sysdep.c [HAVE_TUNABLES]: Include dl-tunables.h
(_dl_sysdep_start): Call __tunables_init.
* elf/dl-tunable-types.h: New file.
* elf/dl-tunables.c: New file.
* elf/dl-tunables.h: New file.
* elf/dl-tunables.list: New file.
* malloc/tst-malloc-usable-static.c: New test case.
* malloc/Makefile (tests-static): Add it.
* malloc/arena.c [HAVE_TUNABLES]: Include dl-tunables.h.
Define TUNABLE_NAMESPACE.
(DL_TUNABLE_CALLBACK (set_mallopt_check)): New function.
(DL_TUNABLE_CALLBACK_FNDECL): New macro. Use it to define
callback functions.
(ptmalloc_init): Set tunable values.
* scripts/gen-tunables.awk: New file.
* sysdeps/mach/hurd/dl-sysdep.c: Include dl-tunables.h.
(_dl_sysdep_start): Call __tunables_init.
The new test driver in <support/test-driver.c> has feature parity with
the old one. The main difference is that its hooking mechanism is
based on functions and function pointers instead of macros. This
commit also implements a new environment variable, TEST_COREDUMPS,
which disables the code which disables coredumps (that is, it enables
them if the invocation environment has not disabled them).
<test-skeleton.c> defines wrapper functions so that it is possible to
use existing macros with the new-style hook functionality.
This commit changes only a few test cases to the new test driver, to
make sure that it works as expected.
Make mallopt helper functions for each mallopt parameter so that it
can be called consistently in other areas, like setting tunables.
* malloc/malloc.c (do_set_mallopt_check): New function.
(do_set_mmap_threshold): Likewise.
(do_set_mmaps_max): Likewise.
(do_set_top_pad): Likewise.
(do_set_perturb_byte): Likewise.
(do_set_trim_threshold): Likewise.
(do_set_arena_max): Likewise.
(do_set_arena_test): Likewise.
(__libc_mallopt): Use them.
After the removal of __malloc_initialize_hook, newly compiled
Emacs binaries are no longer able to use these interfaces.
malloc_get_state is only used during the Emacs build process,
so we provide a stub implementation only. Existing Emacs binaries
will not call this stub function, but still reference the symbol.
The rewritten tst-mallocstate test constructs a dumped heap
which should approximates what existing Emacs binaries pass
to glibc malloc.
The M_ARENA_MAX and M_ARENA_TEST macros are defined in malloc.c as
well as malloc.h, and the former is unnecessary. This patch removes
the duplicate. Tested on x86_64 to verify that the generated code
remains unchanged barring changed line numbers to __malloc_assert.
* malloc/malloc.c (M_ARENA_TEST, M_ARENA_MAX): Remove.
The M_ARENA_* mallopt parameters are in wide use in production to
control the number of arenas that a long lived process creates and
hence there is no point in stating that this interface is non-public.
Document this interface and remove the obsolete comment.
* manual/memory.texi (M_ARENA_TEST): Add documentation.
(M_ARENA_MAX): Likewise.
* malloc/malloc.c: Remove obsolete comment.
This is a trivial change to add the static tests only to tests-static
and then adding all of tests-static to the tests target to make it
look consistent with some other Makefiles. This avoids having to
duplicate the test names across the two make targets.
* malloc/Makefile (tests): Remove individual static test names
and just add all of tests-static.
Existing interposed mallocs do not define the glibc-internal
fork callbacks (and they should not), so statically interposed
mallocs lead to link failures because the strong reference from
fork pulls in glibc's malloc, resulting in multiple definitions
of malloc-related symbols.
The dynamic linker currently uses __libc_memalign for TLS-related
allocations. The goal is to switch to malloc instead. If the minimal
malloc follows the ABI fundamental alignment, we can assume that malloc
provides this alignment, and thus skip explicit alignment in a few
cases as an optimization.
It was requested on libc-alpha that MALLOC_ALIGNMENT should be used,
although this results in wasted space if MALLOC_ALIGNMENT is larger
than the fundamental alignment. (The dynamic linker cannot assume
that the non-minimal malloc will provide an alignment of
MALLOC_ALIGNMENT; the ABI provides _Alignof (max_align_t) only.)
It is necessary to preserve the invariant that if an arena is
on the free list, it has thread attach count zero. Otherwise,
when arena_thread_freeres sees the zero attach count, it will
add it, and without the invariant, an arena could get pushed
to the list twice, resulting in a cycle.
One possible execution trace looks like this:
Thread 1 examines free list and observes it as empty.
Thread 2 exits and adds its arena to the free list,
with attached_threads == 0).
Thread 1 selects this arena in reused_arena (not from the free list).
Thread 1 increments attached_threads and attaches itself.
(The arena remains on the free list.)
Thread 1 exits, decrements attached_threads,
and adds the arena to the free list.
The final step creates a cycle in the usual way (by overwriting the
next_free member with the former list head, while there is another
list item pointing to the arena structure).
tst-malloc-thread-exit exhibits this issue, but it was only visible
with a debugger because the incorrect fix in bug 19243 removed
the assert from get_free_list.
Right now tilegx is right on the verge of timeout when it runs,
so adding a bit of headroom seems like the right thing; we
see failures when running tests in parallel.
Before this change, the while loop in reused_arena which avoids
returning a corrupt arena would never execute its body if the selected
arena were not corrupt. As a result, result == begin after the loop,
and the function returns NULL, triggering fallback to mmap.
__malloc_initialize_hook is interposed by application code, so
the usual approach to define a compatibility symbol does not work.
This commit adds a new mechanism based on #pragma GCC poison in
<stdc-predef.h>.
For regular mmapped chunks there are two size fields (hence a reduction
by 2 * SIZE_SZ bytes), but for fake chunks, we only have one size field,
so we need to subtract SIZE_SZ bytes.
This was initially reported as Emacs bug 23726.
After the heap rewriting added in commit
4cf6c72fd2 (malloc: Rewrite dumped heap
for compatibility in __malloc_set_state), we can change malloc alignment
for new allocations because the alignment of old allocations no longer
matters.
We need to increase the malloc state version number, so that binaries
containing dumped heaps of the new layout will not try to run on
previous versions of glibc, resulting in obscure crashes.
This commit addresses a failure of tst-malloc-thread-fail on the
affected architectures (32-bit ppc and mips) because the test checks
pointer alignment.
The first SIGUSR1 signal could arrive when sigusr1_sender_pid
was still 0. As a result, kill would send SIGSTOP to the
entire process group. This would cause the test to hang before
printing any output.
This commit also adds a sched_yield to the signal source, so that
it does not flood the parent process with signals it has never a
chance to handle.
Even with these changes, tst-mallocfork2 still fails reliably
after the fix in commit commit 56290d6e76
(Increase fork signal safety for single-threaded processes) is
backed out.
This will allow us to change many aspects of the malloc implementation
while preserving compatibility with existing Emacs binaries.
As a result, existing Emacs binaries will have a larger RSS, and Emacs
needs a few more milliseconds to start. This overhead is specific
to Emacs (and will go away once Emacs switches to its internal malloc).
The new checks to make free and realloc compatible with the dumped heap
are confined to the mmap paths, which are already quite slow due to the
munmap overhead.
This commit weakens some security checks, but only for heap pointers
in the dumped main arena. By default, this area is empty, so those
checks are as effective as before.
This provides a band-aid and addresses the scenario where fork is
called from a signal handler while the process is in the malloc
subsystem (or has acquired the libio list lock). It does not
address the general issue of async-signal-safety of fork;
multi-threaded processes are not covered, and some glibc
subsystems have fork handlers which are not async-signal-safe.
The fork handler now runs so late that there is no risk anymore that
other fork handlers in the same thread use malloc, so it is no
longer necessary to install malloc hooks which made a subset
of malloc functionality available to the thread that called fork.
Previously, a thread M invoking fork would acquire locks in this order:
(M1) malloc arena locks (in the registered fork handler)
(M2) libio list lock
A thread F invoking flush (NULL) would acquire locks in this order:
(F1) libio list lock
(F2) individual _IO_FILE locks
A thread G running getdelim would use this order:
(G1) _IO_FILE lock
(G2) malloc arena lock
After executing (M1), (F1), (G1), none of the threads can make progress.
This commit changes the fork lock order to:
(M'1) libio list lock
(M'2) malloc arena locks
It explicitly encodes the lock order in the implementations of fork,
and does not rely on the registration order, thus avoiding the deadlock.
* malloc/Makefile ($(objpfx)tst-malloc-backtrace,
$(objpfx)tst-malloc-thread-exit, $(objpfx)tst-malloc-thread-fail): Use
$(shared-thread-library) instead of hardcoding the path to libpthread.
This test case exercises unusual code paths in allocation functions,
related to allocation failures. Specifically, the test can reveal
the following bugs:
(a) calloc returns non-zero memory on fallback to sysmalloc.
(b) calloc can self-deadlock because it fails to release
the arena lock on certain allocation failures.
(c) pvalloc can dereference a NULL arena pointer.
(a) and (b) appear specific to a faulty downstream backport.
(c) was fixed as part of commit 10ad46bc65.
The test for (a) was inspired by a reproducer supplied by Jeff Layton.
* malloc/arena.c (list_lock): Document lock ordering requirements.
(free_list_lock): New lock.
(ptmalloc_lock_all): Comment on free_list_lock.
(ptmalloc_unlock_all2): Reinitialize free_list_lock.
(detach_arena): Update comment. free_list_lock is now needed.
(_int_new_arena): Use free_list_lock around detach_arena call.
Acquire arena lock after list_lock. Add comment, including FIXME
about incorrect synchronization.
(get_free_list): Switch to free_list_lock.
(reused_arena): Acquire free_list_lock around detach_arena call
and attached threads counter update. Add two FIXMEs about
incorrect synchronization.
(arena_thread_freeres): Switch to free_list_lock.
* malloc/malloc.c (struct malloc_state): Update comments to
mention free_list_lock.
reused_arena can increase the attached thread count of arenas on the
free list. This means that the assertion that the reference count is
zero is incorrect. In this case, the reference count initialization
is incorrect as well and could cause arenas to be put on the free
list too early (while they still have attached threads).
* malloc/arena.c (get_free_list): Remove assert and adjust
reference count handling. Add comment about reused_arena
interaction.
(reused_arena): Add comments abount get_free_list interaction.
* malloc/tst-malloc-thread-exit.c: New file.
* malloc/Makefile (tests): Add tst-malloc-thread-exit.
(tst-malloc-thread-exit): Link against libpthread.
This patch converts a few more function definitions in glibc from
old-style K&R to prototype style. This is sufficient to build and
test on x86_64 and x86 with -Wold-style-definition (I'll test on some
more architectures before proposing the actual addition of
-Wold-style-definition).
Tested for x86_64 and x86 with -Wold-style-definition in use
(testsuite - this patch affects files containing assertions).
* io/fts.c (fts_open): Convert to prototype-style function
definition.
* malloc/mcheck.c (mcheck): Likewise.
(mcheck_pedantic): Likewise.
* posix/regexec.c (re_search_2_stub): Likewise. Use
internal_function.
(re_search_internal): Likewise.
* resolv/res_init.c [RESOLVSORT] (net_mask): Convert to
prototype-style function definition.
* sunrpc/clnt_udp.c (clntudp_call): Likewise.
* sunrpc/pmap_rmt.c (clnt_broadcast): Likewise.
* sunrpc/rpcsvc/rusers.x (xdr_utmp): Likewise.
(xdr_utmpptr): Likewise.
(xdr_utmparr): Likewise.
(xdr_utmpidle): Likewise.
(xdr_utmpidleptr): Likewise.
(xdr_utmpidlearr): Likewise.
This mostly automatically-generated patch converts 113 function
definitions in glibc from old-style K&R to prototype-style. Following
my other recent such patches, this one deals with the case of function
definitions in files that either contain assertions or where grep
suggested they might contain assertions - and thus where it isn't
possible to use a simple object code comparison as a sanity check on
the correctness of the patch, because line numbers are changed.
A few such automatically-generated changes needed to be supplemented
by manual changes for the result to compile. openat64 had a prototype
declaration with "..." but an old-style definition in
sysdeps/unix/sysv/linux/dl-openat64.c, and "..." needed adding to the
generated prototype in the definition (I've filed
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68024> for diagnosing
such cases in GCC; the old state was undefined behavior not requiring
a diagnostic, but one seems a good idea). In addition, as Florian has
noted regparm attribute mismatches between declaration and definition
are only diagnosed for prototype definitions, and five functions
needed internal_function added to their definitions (in the case of
__pthread_mutex_cond_lock, via the macro definition of
__pthread_mutex_lock) to compile on i386.
After this patch is in, remaining old-style definitions are probably
most readily fixed manually before we can turn on
-Wold-style-definition for all builds.
Tested for x86_64 and x86 (testsuite).
* crypt/md5-crypt.c (__md5_crypt_r): Convert to prototype-style
function definition.
* crypt/sha256-crypt.c (__sha256_crypt_r): Likewise.
* crypt/sha512-crypt.c (__sha512_crypt_r): Likewise.
* debug/backtracesyms.c (__backtrace_symbols): Likewise.
* elf/dl-minimal.c (_itoa): Likewise.
* hurd/hurdmalloc.c (malloc): Likewise.
(free): Likewise.
(realloc): Likewise.
* inet/inet6_option.c (inet6_option_space): Likewise.
(inet6_option_init): Likewise.
(inet6_option_append): Likewise.
(inet6_option_alloc): Likewise.
(inet6_option_next): Likewise.
(inet6_option_find): Likewise.
* io/ftw.c (FTW_NAME): Likewise.
(NFTW_NAME): Likewise.
(NFTW_NEW_NAME): Likewise.
(NFTW_OLD_NAME): Likewise.
* libio/iofwide.c (_IO_fwide): Likewise.
* libio/strops.c (_IO_str_init_static_internal): Likewise.
(_IO_str_init_static): Likewise.
(_IO_str_init_readonly): Likewise.
(_IO_str_overflow): Likewise.
(_IO_str_underflow): Likewise.
(_IO_str_count): Likewise.
(_IO_str_seekoff): Likewise.
(_IO_str_pbackfail): Likewise.
(_IO_str_finish): Likewise.
* libio/wstrops.c (_IO_wstr_init_static): Likewise.
(_IO_wstr_overflow): Likewise.
(_IO_wstr_underflow): Likewise.
(_IO_wstr_count): Likewise.
(_IO_wstr_seekoff): Likewise.
(_IO_wstr_pbackfail): Likewise.
(_IO_wstr_finish): Likewise.
* locale/programs/localedef.c (normalize_codeset): Likewise.
* locale/programs/locarchive.c (add_locale_to_archive): Likewise.
(add_locales_to_archive): Likewise.
(delete_locales_from_archive): Likewise.
* malloc/malloc.c (__libc_mallinfo): Likewise.
* math/gen-auto-libm-tests.c (init_fp_formats): Likewise.
* misc/tsearch.c (__tfind): Likewise.
* nptl/pthread_attr_destroy.c (__pthread_attr_destroy): Likewise.
* nptl/pthread_attr_getdetachstate.c
(__pthread_attr_getdetachstate): Likewise.
* nptl/pthread_attr_getguardsize.c (pthread_attr_getguardsize):
Likewise.
* nptl/pthread_attr_getinheritsched.c
(__pthread_attr_getinheritsched): Likewise.
* nptl/pthread_attr_getschedparam.c
(__pthread_attr_getschedparam): Likewise.
* nptl/pthread_attr_getschedpolicy.c
(__pthread_attr_getschedpolicy): Likewise.
* nptl/pthread_attr_getscope.c (__pthread_attr_getscope):
Likewise.
* nptl/pthread_attr_getstack.c (__pthread_attr_getstack):
Likewise.
* nptl/pthread_attr_getstackaddr.c (__pthread_attr_getstackaddr):
Likewise.
* nptl/pthread_attr_getstacksize.c (__pthread_attr_getstacksize):
Likewise.
* nptl/pthread_attr_init.c (__pthread_attr_init_2_1): Likewise.
(__pthread_attr_init_2_0): Likewise.
* nptl/pthread_attr_setdetachstate.c
(__pthread_attr_setdetachstate): Likewise.
* nptl/pthread_attr_setguardsize.c (pthread_attr_setguardsize):
Likewise.
* nptl/pthread_attr_setinheritsched.c
(__pthread_attr_setinheritsched): Likewise.
* nptl/pthread_attr_setschedparam.c
(__pthread_attr_setschedparam): Likewise.
* nptl/pthread_attr_setschedpolicy.c
(__pthread_attr_setschedpolicy): Likewise.
* nptl/pthread_attr_setscope.c (__pthread_attr_setscope):
Likewise.
* nptl/pthread_attr_setstack.c (__pthread_attr_setstack):
Likewise.
* nptl/pthread_attr_setstackaddr.c (__pthread_attr_setstackaddr):
Likewise.
* nptl/pthread_attr_setstacksize.c (__pthread_attr_setstacksize):
Likewise.
* nptl/pthread_condattr_setclock.c (pthread_condattr_setclock):
Likewise.
* nptl/pthread_create.c (__find_in_stack_list): Likewise.
* nptl/pthread_getattr_np.c (pthread_getattr_np): Likewise.
* nptl/pthread_mutex_cond_lock.c (__pthread_mutex_lock): Define to
use internal_function.
* nptl/pthread_mutex_init.c (__pthread_mutex_init): Convert to
prototype-style function definition.
* nptl/pthread_mutex_lock.c (__pthread_mutex_lock): Likewise.
(__pthread_mutex_cond_lock_adjust): Likewise. Use
internal_function.
* nptl/pthread_mutex_timedlock.c (pthread_mutex_timedlock):
Convert to prototype-style function definition.
* nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock):
Likewise.
* nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_usercnt):
Likewise.
(__pthread_mutex_unlock): Likewise.
* nptl_db/td_ta_clear_event.c (td_ta_clear_event): Likewise.
* nptl_db/td_ta_set_event.c (td_ta_set_event): Likewise.
* nptl_db/td_thr_clear_event.c (td_thr_clear_event): Likewise.
* nptl_db/td_thr_event_enable.c (td_thr_event_enable): Likewise.
* nptl_db/td_thr_set_event.c (td_thr_set_event): Likewise.
* nss/makedb.c (process_input): Likewise.
* posix/fnmatch.c (__strchrnul): Likewise.
(__wcschrnul): Likewise.
(fnmatch): Likewise.
* posix/fnmatch_loop.c (FCT): Likewise.
* posix/glob.c (globfree): Likewise.
(__glob_pattern_type): Likewise.
(__glob_pattern_p): Likewise.
* posix/regcomp.c (re_compile_pattern): Likewise.
(re_set_syntax): Likewise.
(re_compile_fastmap): Likewise.
(regcomp): Likewise.
(regerror): Likewise.
(regfree): Likewise.
* posix/regexec.c (regexec): Likewise.
(re_match): Likewise.
(re_search): Likewise.
(re_match_2): Likewise.
(re_search_2): Likewise.
(re_search_stub): Likewise. Use internal_function
(re_copy_regs): Likewise.
(re_set_registers): Convert to prototype-style function
definition.
(prune_impossible_nodes): Likewise. Use internal_function.
* resolv/inet_net_pton.c (inet_net_pton): Convert to
prototype-style function definition.
(inet_net_pton_ipv4): Likewise.
* stdlib/strtod_l.c (____STRTOF_INTERNAL): Likewise.
* sysdeps/pthread/aio_cancel.c (aio_cancel): Likewise.
* sysdeps/pthread/aio_suspend.c (aio_suspend): Likewise.
* sysdeps/pthread/timer_delete.c (timer_delete): Likewise.
* sysdeps/unix/sysv/linux/dl-openat64.c (openat64): Likewise.
Make variadic.
* time/strptime_l.c (localtime_r): Convert to prototype-style
function definition.
* wcsmbs/mbsnrtowcs.c (__mbsnrtowcs): Likewise.
* wcsmbs/mbsrtowcs_l.c (__mbsrtowcs_l): Likewise.
* wcsmbs/wcsnrtombs.c (__wcsnrtombs): Likewise.
* wcsmbs/wcsrtombs.c (__wcsrtombs): Likewise.
In the per-thread arenas we apply trim_threshold-based checks
to the extra space between the pad and the top_area. This isn't
quite accurate and instead we should be harmonizing with the way
in which trim_treshold is applied everywhere else like sysrtim
and _int_free. The trimming check should be based on the size of
the top chunk and only the size of the top chunk. The following
patch harmonizes the trimming and make it consistent for the main
arena and thread arenas.
In the old code a large padding request might have meant that
trimming was not triggered. Now trimming is considered first based
on the chunk, then the pad is subtracted, and the remainder trimmed.
This is how all the other trimmings operate. I didn't measure the
performance difference of this change because it corrects what I
consider to be a behavioural anomaly. We'll need some profile driven
optimization to make this code better, and even there Ondrej and
others have better ideas on how to speedup malloc.
Tested on x86_64 with no regressions. Already reviewed by Siddhesh
Poyarekar and Mel Gorman here and discussed here:
https://sourceware.org/ml/libc-alpha/2015-05/msg00002.html
While doing code review I converted another bespoke round down, and
corrected a comment.
The comment spoke about keeping at least one page allocated even
during systrim, which is not correct. The code does nothing to keep
a page allocated. The code does attempt to keep PAD padding as
documented in comments and MINSIZE as required by design.
Historically in 2002 when Ulrich wrote the code (fa8d436c) the math
was inlined into one statement which did reserve an extra page:
extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz;
There is no reason given for this extra page.
In 2010 Anton Branchard's change (b9b42ee0) from division
to shifts removed the extra page by dropping the "+ (pagesiz-1), which
mean we might have attempted to return -0 via MORECORE. The fix by Will
Newton in 2014 added a check for extra being zero (51a7380b).
From first principles I see no reason why we should keep an extra
page of memory from being trimmed back to the OS. The only sensible
interface is to honour PAD padding as the function is documented,
with the caveat the MINSIZE is maintained for the top chunk.
Given that we've been using this code for 5+ years with no extra
page allocated is sufficient evidence that the comment should be changed
to match the code that I'm touching.
Tested on x86_64 and i686, no regressions.
If allocation on a non-main arena fails, the main arena is used
without checking to see if it is corrupt. Add a check that avoids the
main arena if it is corrupt.
* malloc/arena.c (arena_get_retry): Don't use main_arena if it is
corrupt.
The arena pointer in the first argument to arena_get2 was used in the
old days before per-thread arenas. They're unused now and hence can
be dropped.
ChangeLog:
* malloc/arena.c (arena_get2): Drop unused argument.
(arena_lock): Adjust.
(arena_get_retry): Likewise.
mksquashfs was reported in openSUSE to be causing segmentation faults when
creating installation images. Testing showed that mksquashfs sometimes
failed and could be reproduced within 10 attempts. The core dump looked
like the heap top was corrupted and was pointing to an unmapped area. In
other cases, this has been due to an application corrupting glibc structures
but mksquashfs appears to be fine in this regard.
The problem is that heap_trim is "growing" the top into unmapped space.
If the top chunk == MINSIZE then top_area is -1 and this check does not
behave as expected due to a signed/unsigned comparison
if (top_area <= pad)
return 0;
The next calculation extra = ALIGN_DOWN(top_area - pad, pagesz) calculates
extra as a negative number which also is unnoticed due to a signed/unsigned
comparison. We then call shrink_heap(heap, negative_number) which crashes
later. This patch adds a simple check against MINSIZE to make sure extra
does not become negative. It adds a cast to hint to the reader that this
is a signed vs unsigned issue.
Without the patch, mksquash fails within 10 attempts. With it applied, it
completed 1000 times without error. The standard test suite "make check"
showed no changes in the summary of test results.
[BZ #17581] The checking chain of unused chunks was terminated by a hash of
the block pointer, which was sometimes confused with the chunk length byte.
We now avoid using a length byte equal to the magic byte.
When the malloc subsystem detects some kind of memory corruption,
depending on the configuration it prints the error, a backtrace, a
memory map and then aborts the process. In this process, the
backtrace() call may result in a call to malloc, resulting in
various kinds of problematic behavior.
In one case, the malloc it calls may detect a corruption and call
backtrace again, and a stack overflow may result due to the infinite
recursion. In another case, the malloc it calls may deadlock on an
arena lock with the malloc (or free, realloc, etc.) that detected the
corruption. In yet another case, if the program is linked with
pthreads, backtrace may do a pthread_once initialization, which
deadlocks on itself.
In all these cases, the program exit is not as intended. This is
avoidable by marking the arena that malloc detected a corruption on,
as unusable. The following patch does that. Features of this patch
are as follows:
- A flag is added to the mstate struct of the arena to indicate if the
arena is corrupt.
- The flag is checked whenever malloc functions try to get a lock on
an arena. If the arena is unusable, a NULL is returned, causing the
malloc to use mmap or try the next arena.
- malloc_printerr sets the corrupt flag on the arena when it detects a
corruption
- free does not concern itself with the flag at all. It is not
important since the backtrace workflow does not need free. A free
in a parallel thread may cause another corruption, but that's not
new
- The flag check and set are not atomic and may race. This is fine
since we don't care about contention during the flag check. We want
to make sure that the malloc call in the backtrace does not trip on
itself and all that action happens in the same thread and not across
threads.
I verified that the test case does not show any regressions due to
this patch. I also ran the malloc benchmarks and found an
insignificant difference in timings (< 2%).
* malloc/Makefile (tests): New test case tst-malloc-backtrace.
* malloc/arena.c (arena_lock): Check if arena is corrupt.
(reused_arena): Find a non-corrupt arena.
(heap_trim): Pass arena to unlink.
* malloc/hooks.c (malloc_check_get_size): Pass arena to
malloc_printerr.
(top_check): Likewise.
(free_check): Likewise.
(realloc_check): Likewise.
* malloc/malloc.c (malloc_printerr): Add arena argument.
(unlink): Likewise.
(munmap_chunk): Adjust.
(ARENA_CORRUPTION_BIT): New macro.
(arena_is_corrupt): Likewise.
(set_arena_corrupt): Likewise.
(sysmalloc): Use mmap if there are no usable arenas.
(_int_malloc): Likewise.
(__libc_malloc): Don't fail if arena_get returns NULL.
(_mid_memalign): Likewise.
(__libc_calloc): Likewise.
(__libc_realloc): Adjust for additional argument to
malloc_printerr.
(_int_free): Likewise.
(malloc_consolidate): Likewise.
(_int_realloc): Likewise.
(_int_memalign): Don't touch corrupt arenas.
* malloc/tst-malloc-backtrace.c: New test case.
Trimming heaps is a balance between saving memory and the system overhead
required to update page tables and discard allocated pages. The malloc
option M_TRIM_THRESHOLD is a tunable that users are meant to use to decide
where this balance point is but it is only applied to the main arena.
For scalability reasons, glibc malloc has per-thread heaps but these are
shrunk with madvise() if there is one page free at the top of the heap.
In some circumstances this can lead to high system overhead if a thread
has a control flow like
while (data_to_process) {
buf = malloc(large_size);
do_stuff();
free(buf);
}
For a large size, the free() will call madvise (pagetable teardown, page
free and TLB flush) every time followed immediately by a malloc (fault,
kernel page alloc, zeroing and charge accounting). The kernel overhead
can dominate such a workload.
This patch allows the user to tune when madvise gets called by applying
the trim threshold to the per-thread heaps and using similar logic to the
main arena when deciding whether to shrink. Alternatively if the dynamic
brk/mmap threshold gets adjusted then the new values will be obeyed by
the per-thread heaps.
Bug 17195 was a test case motivated by a problem encountered in scientific
applications written in python that performance badly due to high page fault
overhead. The basic operation of such a program was posted by Julian Taylor
https://sourceware.org/ml/libc-alpha/2015-02/msg00373.html
With this patch applied, the overhead is eliminated. All numbers in this
report are in seconds and were recorded by running Julian's program 30
times.
pyarray
glibc madvise
2.21 v2
System min 1.81 ( 0.00%) 0.00 (100.00%)
System mean 1.93 ( 0.00%) 0.02 ( 99.20%)
System stddev 0.06 ( 0.00%) 0.01 ( 88.99%)
System max 2.06 ( 0.00%) 0.03 ( 98.54%)
Elapsed min 3.26 ( 0.00%) 2.37 ( 27.30%)
Elapsed mean 3.39 ( 0.00%) 2.41 ( 28.84%)
Elapsed stddev 0.14 ( 0.00%) 0.02 ( 82.73%)
Elapsed max 4.05 ( 0.00%) 2.47 ( 39.01%)
glibc madvise
2.21 v2
User 141.86 142.28
System 57.94 0.60
Elapsed 102.02 72.66
Note that almost a minutes worth of system time is eliminted and the
program completes 28% faster on average.
To illustrate the problem without python this is a basic test-case for
the worst case scenario where every free is a madvise followed by a an alloc
/* gcc bench-free.c -lpthread -o bench-free */
static int num = 1024;
void __attribute__((noinline,noclone)) dostuff (void *p)
{
}
void *worker (void *data)
{
int i;
for (i = num; i--;)
{
void *m = malloc (48*4096);
dostuff (m);
free (m);
}
return NULL;
}
int main()
{
int i;
pthread_t t;
void *ret;
if (pthread_create (&t, NULL, worker, NULL))
exit (2);
if (pthread_join (t, &ret))
exit (3);
return 0;
}
Before the patch, this resulted in 1024 calls to madvise. With the patch applied,
madvise is called twice because the default trim threshold is high enough to avoid
this.
This a more complex case where there is a mix of frees. It's simply a different worker
function for the test case above
void *worker (void *data)
{
int i;
int j = 0;
void *free_index[num];
for (i = num; i--;)
{
void *m = malloc ((i % 58) *4096);
dostuff (m);
if (i % 2 == 0) {
free (m);
} else {
free_index[j++] = m;
}
}
for (; j >= 0; j--)
{
free(free_index[j]);
}
return NULL;
}
glibc 2.21 calls malloc 90305 times but with the patch applied, it's
called 13438. Increasing the trim threshold will decrease the number of
times it's called with the option of eliminating the overhead.
ebizzy is meant to generate a workload resembling common web application
server workloads. It is threaded with a large working set that at its core
has an allocation, do_stuff, free loop that also hits this case. The primary
metric of the benchmark is records processed per second. This is running on
my desktop which is a single socket machine with an I7-4770 and 8 cores.
Each thread count was run for 30 seconds. It was only run once as the
performance difference is so high that the variation is insignificant.
glibc 2.21 patch
threads 1 10230 44114
threads 2 19153 84925
threads 4 34295 134569
threads 8 51007 183387
Note that the saving happens to be a concidence as the size allocated
by ebizzy was less than the default threshold. If a different number of
chunks were specified then it may also be necessary to tune the threshold
to compensate
This is roughly quadrupling the performance of this benchmark. The difference in
system CPU usage illustrates why.
ebizzy running 1 thread with glibc 2.21
10230 records/s 306904
real 30.00 s
user 7.47 s
sys 22.49 s
22.49 seconds was spent in the kernel for a workload runinng 30 seconds. With the
patch applied
ebizzy running 1 thread with patch applied
44126 records/s 1323792
real 30.00 s
user 29.97 s
sys 0.00 s
system CPU usage was zero with the patch applied. strace shows that glibc
running this workload calls madvise approximately 9000 times a second. With
the patch applied madvise was called twice during the workload (or 0.06
times per second).
2015-02-10 Mel Gorman <mgorman@suse.de>
[BZ #17195]
* malloc/arena.c (free): Apply trim threshold to per-thread heaps
as well as the main arena.
This seems to have been left behind as an artifact of some old changes
and can now be merged. Verified that the only generated code change
on x86_64 is that of line numbers in asserts, like so:
@@ -27253,7 +27253,7 @@ Disassembly of section .text:
416f09: 48 89 42 20 mov %rax,0x20(%rdx)
416f0d: e9 7e f6 ff ff jmpq 416590 <_int_free+0x230>
416f12: b9 3f 9f 4a 00 mov $0x4a9f3f,%ecx
- 416f17: ba d5 0f 00 00 mov $0xfd5,%edx
+ 416f17: ba d6 0f 00 00 mov $0xfd6,%edx
416f1c: be a8 9b 4a 00 mov $0x4a9ba8,%esi
416f21: bf 6a 9c 4a 00 mov $0x4a9c6a,%edi
416f26: e8 45 e8 ff ff callq 415770 <__malloc_assert>
We are replacing all of the bespoke alignment code with
ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN.
This cleans up malloc/malloc.c, malloc/arena.c, and
elf/dl-reloc.c. It also makes all the code consistently
use pagesize, and powerof2 as required.
Code size is reduced with the removal of precomputed
pagemask, and use of pagesize instead. No measurable
difference in performance.
No regressions on x86_64.
[BZ #17581] The checking chain of unused chunks was terminated by a hash of
the block pointer, which was sometimes confused with the chunk length byte.
The chain is now terminated by a NULL byte.
The current scheme to identify which module a translation unit is
built in depends on defining multiple macros IS_IN_* and also defining
NOT_IN_libc if we're building a non-libc module. In addition, there
is an IN_LIB macro that does effectively the same thing, but for
different modules (notably the systemtap probes). This macro scheme
unifies both ideas to use just one macro IN_MODULE and assign it a
value depending on the module it is being built into. If the module
is not defined, it defaults to MODULE_libc.
Patches that follow will replace uses of IS_IN_* variables with the
IS_IN() macro. libc-symbols.h has been converted already to give an
example of how such a transition will look.
Verified that there are no relevant binary changes. One source change
that will crop up repeatedly is that of nscd_stat, since it uses the
build timestamp as a constant in its logic.
* Makeconfig (in-module): Get value of libof set for the
translation unit.
(CPPFLAGS): Use $(in-module).
* Makerules: Don't suffix routine names for nonlib.
* include/libc-modules.h: New file.
* include/libc-symbols.h: Include libc-modules.h
(IS_IN): New macro to replace IS_IN_* macros.
* elf/Makefile: Set libof-* for each routine.
* elf/rtld-Rules: Likewise.
* extra-modules.mk: Likewise.
* iconv/Makefile: Likewise.
* iconvdata/Makefile: Likewise.
* locale/Makefile: Likewise.
* malloc/Makefile: Likewise.
* nss/Makefile: Likewise.
* sysdeps/gnu/Makefile: Likewise.
* sysdeps/ieee754/ldbl-opt/Makefile: Likewise.
* sysdeps/unix/sysv/linux/Makefile: Likewise.
* sysdeps/s390/s390-64/Makefile: Likewise.
* nscd/Makefile: Set libof-* for each routine. Set CFLAGS and
CPPFLAGS for nscd instead of nonlib.
malloc_info is defined in the same file as malloc and free, but is not
an ISO C function, so should be a weak symbol. This patch makes it
so.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).
[BZ #17570]
* malloc/malloc.c (malloc_info): Rename to __malloc_info and
define as weak alias of __malloc_info.
Merge the latest version of the obstack.c and obstack.h files
from gnulib. The majority of this change is coding style and
cosmetic comment changes but it also fixes a -Wundef warning
in the build as a side effect.
2014-07-02 Will Newton <will.newton@linaro.org>
* malloc/obstack.c: Merge from gnulib master.
[HAVE_CONFIG_H]: Remove conditional code.
[!_LIBC]: Include config.h.
[!ELIDE_CODE]: Don't include inttypes.h, include
stdint.h unconditionally.
(print_and_abort): Mark as _Noreturn.
(_obstack_allocated_p): Mark as __attribute_pure__.
(obstack_free): Rename to __obstack_free.
[!__attribute__]: Remove conditional code.
* malloc/obstack.h: Merge from gnulib master.
[__cplusplus]: Move conditional down.
[!__attribute_pure__]: Define __attribute_pure__ here
if it is not already defined.
(_obstack_memory_used): Mark as __attribute_pure__.
[!__obstack_free]: Define as obstack_free.
[__GNUC__]: Remove check for ancient NeXT gcc.
Due to my bad review suggestion for the fix for BZ #15089 a check
was removed from systrim to prevent sbrk being called with a zero
argument. Add the check back to avoid this useless work.
ChangeLog:
2014-06-19 Will Newton <will.newton@linaro.org>
* malloc/malloc.c (systrim): If extra is zero then return
early.
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.
The current malloc_info xml output only has information about
allocations on the heap. Display information about number of mappings
and total mmapped size to this to complete the picture.
The nested function mi_arena was removed from malloc_info
and made into a non-nested static inline function of the same
name with the correct set of arguments passed from malloc_info.
This enables building glibc with compilers that don't support
nested functions. Future work on malloc_info should remove these
functions entirely to support JSON format output. Therefore we
do the minimum required to remove the nested function.
glibc's Makeconfig defines some variables such as $(libm) and $(libdl)
for linking with libraries built by glibc, and nptl/Makeconfig
(included by the toplevel Makeconfig) defines others such as
$(shared-thread-library).
In some places glibc's Makefiles use those variables when linking
against the relevant libraries, but in other places they hardcode the
location of the libraries in the build tree. This patch cleans up
various places to use the variables that already exist (in the case of
libm, replacing several duplicate definitions of a $(link-libm)
variable in subdirectory Makefiles). (It's not necessarily exactly
equivalent to what the existing code does - in particular,
$(shared-thread-library) includes libpthread_nonshared, but is
replacing places that just referred to libpthread.so. But I think
that change is desirable on the general principle of linking things as
close as possible to the way in which they would be linked with an
installed library, unless there is a clear reason not to do so.)
To support running tests with an installed copy of glibc without
needing the full build tree from when that copy was built, I think it
will be useful to use such variables more generally and systematically
- every time the rules for building a test refer to some file from the
build tree that's also installed by glibc, use a makefile variable so
that the installed-testing case can point those variables to installed
copies of the files. This patch just deals with straightforward cases
where such variables already exist.
It's quite possible some uses of $(shared-thread-library) should
actually be a new $(thread-library) variable that's set appropriately
in the --disable-shared case, if those uses would in fact work without
shared libraries. I didn't change the status quo that those cases
hardcode use of a shared library whether or not it's actually needed
(but other uses such as $(libm) and $(libdl) would now get the static
library if the shared library isn't built, when some previously
hardcoded use of the shared library - if they actually need shared
libraries, the test itself needs an enable-shared conditional anyway).
Tested x86_64.
* benchtests/Makefile
($(addprefix $(objpfx)bench-,$(bench-math))): Depend on $(libm),
not $(common-objpfx)math/libm.so.
($(addprefix $(objpfx)bench-,$(bench-pthread))): Depend on
$(shared-thread-library), not $(common-objpfx)nptl/libpthread.so.
* elf/Makefile ($(objpfx)noload): Depend on $(libdl), not
$(common-objpfx)dlfcn/libdl.so.
($(objpfx)tst-audit8): Depend on $(libm), not
$(common-objpfx)math/libm.so.
* malloc/Makefile ($(objpfx)libmemusage.so): Depend on $(libdl),
not $(common-objpfx)dlfcn/libdl.so.
* math/Makefile
($(addprefix $(objpfx),$(filter-out $(tests-static),$(tests)))):
Depend on $(libm), not $(objpfx)libm.so. Do not condition on
[$(build-shared) = yes].
($(objpfx)test-fenv-tls): Depend on $(shared-thread-library), not
$(common-objpfx)nptl/libpthread.so.
* misc/Makefile ($(objpfx)tst-tsearch): Depend on $(libm), not
$(common-objpfx)math/libm.so$(libm.so-version) or
$(common-objpfx)math/libm.a depending on [$(build-shared) = yes].
* nptl/Makefile ($(objpfx)tst-unload): Depend on $(libdl), not
$(common-objpfx)dlfcn/libdl.so.
* setjmp/Makefile (link-libm): Remove variable.
($(objpfx)tst-setjmp-fp): Depend on $(libm), not $(link-libm).
* stdio-common/Makefile (link-libm): Remove variable.
($(objpfx)tst-printf-round): Depend on $(libm), not $(link-libm).
* stdlib/Makefile (link-libm): Remove variable.
($(objpfx)bug-getcontext): Depend on $(libm), not $(link-libm).
($(objpfx)tst-strtod-round): Likewise.
($(objpfx)tst-tininess): Likewise.
($(objpfx)tst-strtod-underflow): Likewise.
($(objpfx)tst-strtod6): Likewise.
($(objpfx)tst-tls-atexit): Depend on $(shared-thread-library) and
$(libdl), not $(common-objpfx)nptl/libpthread.so and
$(common-objpfx)dlfcn/libdl.so.
MALLOC_DEBUG is set optionally on the command line. Default the value
to zero if it is not set on the command line, and test its value
with #if rather than #ifdef. Verified the code is identical before
and after this change apart from line numbers.
ChangeLog:
2014-04-11 Will Newton <will.newton@linaro.org>
* malloc/malloc.c [!MALLOC_DEBUG]: #define MALLOC_DEBUG
to zero if it is not defined elsewhere. (mtrim): Test
the value of MALLOC_DEBUG with #if rather than #ifdef.
This patch is a revised and updated version of
<https://sourceware.org/ml/libc-alpha/2014-01/msg00196.html>.
In order to generate overall summaries of the results of all tests in
the glibc testsuite, we need to identify and concatenate the files
with the results of individual tests.
Tomas Dohnalek's patch used $(common-objpfx)*/*.test-result for this.
However, the normal glibc approach is explicit enumeration of the
expected set of files with a given property, rather than all files
matching some pattern like that. Furthermore, we would like to be
able to mark tests as UNRESOLVED if the file with their results is for
some reason missing, and in future we would like to be able to mark
tests as UNSUPPORTED if they are disabled for a particular
configuration (rather than simply having them missing from the list of
tests as at present). Such handling of tests that were not run or did
not record results requires an explicit enumeration of tests.
For the tests following the default makefile rules, $(tests) (and
$(xtests)) provides such an enumeration. Others, however, are added
directly as dependencies of the "tests" and "xtests" makefile
targets. This patch changes the makefiles to put them in variables
tests-special and xtests-special, with appropriate dependencies on the
tests listed there then being added centrally.
Those variables are used in Rules and so need to be set before Rules
is included in a subdirectory makefile, which is often earlier in the
makefile than the dependencies were present before. We previously
discussed the question of where to include Rules; see the question at
<https://sourceware.org/ml/libc-alpha/2012-11/msg00798.html>, and a
discussion in
<https://sourceware.org/ml/libc-alpha/2013-01/msg00337.html> of why
Rules is included early rather than late in subdirectory makefiles.
It was necessary to avoid an indirection through the check-abi target
and get the check-abi-* targets for individual libraries into the
tests-special variable. The intl/ test $(objpfx)tst-gettext.out,
previously built only because of dependencies from other tests, was
also added to tests-special for the same reason.
The entries in tests-special are the full makefile targets, complete
with $(objpfx) and .out. If a future change causes tests to be named
consistently with a .out suffix, this can be changed to include just
the path relative to $(objpfx), without .out.
Tested x86_64, including that the same set of files is generated in
the build directory by a build and testsuite run both before and after
the patch (except for changes to the
elf/tst-null-argv.debug.out.<number> file name), and a build with
run-built-tests=no to verify there aren't any more obvious instances
of the issue Marcus Shawcroft reported with a previous version in
<https://sourceware.org/ml/libc-alpha/2014-01/msg00462.html>.
* Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(tests): Depend on $(tests-special).
* Makerules (check-abi-list): New variable.
(check-abi): Depend on $(check-abi-list).
[$(subdir) = elf] (tests-special): Add
$(objpfx)check-abi-libc.out.
[$(build-shared) = yes && subdir] (tests-special): Add
$(check-abi-list).
[$(build-shared) = yes && subdir] (tests): Do not depend on
check-abi.
* Rules (tests): Depend on $(tests-special).
(xtests): Depend on $(xtests-special).
* catgets/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* conform/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* elf/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* grp/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* iconv/Makefile (xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* iconvdata/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* intl/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable. Also add
$(objpfx)tst-gettext.out.
* io/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* libio/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* malloc/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* misc/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* nptl/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* nptl_db/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* posix/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* resolv/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* stdio-common/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(do-tst-unbputc): Remove target.
(do-tst-printf): Likewise.
* stdlib/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* string/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* sysdeps/x86/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
localedata:
* Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
Objections were raised surrounding the calloc simplification
and it is better to revert the patch, continue discussions
and then submit a new patch for inclusion with all issues
fully addressed.
In <https://sourceware.org/ml/libc-alpha/2014-01/msg00196.html> I
noted it was necessary to add includes of Makeconfig early in various
subdirectory makefiles for the tests-special variable settings added
by that patch to be conditional on configuration information. No-one
commented on the general question there of whether Makeconfig should
always be included immediately after the definition of subdir.
This patch implements that early inclusion of Makeconfig in each
directory (which is a lot easier than consistent placement of includes
of Rules). Includes are added if needed, or moved up if already
present. Subdirectory "all:" targets are removed, since Makeconfig
provides one.
There is potential for further cleanups I haven't done. Rules and
Makerules have code such as
ifneq "$(findstring env,$(origin headers))" ""
headers :=
endif
to override to empty any value of various variables that came from the
environment. I think there is a case for Makeconfig setting all the
subdirectory variables (other than subdir) to empty to ensure no
outside value is going to take effect if a subdirectory fails to
define a variable. (A list of such variables, possibly out of date
and incomplete, is in manual/maint.texi.) Rules and Makerules would
give errors if Makeconfig hadn't already been included, instead of
including it themselves. The special code to override values coming
from the environment would then be obsolete and could be removed.
Tested x86_64, including that installed binaries are identical before
and after the patch.
* argp/Makefile: Include Makeconfig immediately after defining
subdir.
* assert/Makefile: Likewise.
* benchtests/Makefile: Likewise.
* catgets/Makefile: Likewise.
* conform/Makefile: Likewise.
* crypt/Makefile: Likewise.
* csu/Makefile: Likewise.
(all): Remove target.
* ctype/Makefile: Include Makeconfig immediately after defining
subdir.
* debug/Makefile: Likewise.
* dirent/Makefile: Likewise.
* dlfcn/Makefile: Likewise.
* gmon/Makefile: Likewise.
* gnulib/Makefile: Likewise.
* grp/Makefile: Likewise.
* gshadow/Makefile: Likewise.
* hesiod/Makefile: Likewise.
* hurd/Makefile: Likewise.
(all): Remove target.
* iconvdata/Makefile: Include Makeconfig immediately after
defining subdir.
* inet/Makefile: Likewise.
* intl/Makefile: Likewise.
* io/Makefile: Likewise.
* libio/Makefile: Likewise.
(all): Remove target.
* locale/Makefile: Include Makeconfig immediately after defining
subdir.
* login/Makefile: Likewise.
* mach/Makefile: Likewise.
(all): Remove target.
* malloc/Makefile: Include Makeconfig immediately after defining
subdir.
(all): Remove target.
* manual/Makefile: Include Makeconfig immediately after defining
subdir.
* math/Makefile: Likewise.
* misc/Makefile: Likewise.
* nis/Makefile: Likewise.
* nss/Makefile: Likewise.
* po/Makefile: Likewise.
(all): Remove target.
* posix/Makefile: Include Makeconfig immediately after defining
subdir.
* pwd/Makefile: Likewise.
* resolv/Makefile: Likewise.
* resource/Makefile: Likewise.
* rt/Makefile: Likewise.
* setjmp/Makefile: Likewise.
* shadow/Makefile: Likewise.
* signal/Makefile: Likewise.
* socket/Makefile: Likewise.
* soft-fp/Makefile: Likewise.
* stdio-common/Makefile: Likewise.
* stdlib/Makefile: Likewise.
* streams/Makefile: Likewise.
* string/Makefile: Likewise.
* sunrpc/Makefile: Likewise.
(all): Remove target.
* sysvipc/Makefile: Include Makeconfig immediately after defining
subdir.
* termios/Makefile: Likewise.
* time/Makefile: Likewise.
* timezone/Makefile: Likewise.
(all): Remove target.
* wcsmbs/Makefile: Include Makeconfig immediately after defining
subdir.
* wctype/Makefile: Likewise.
libidn/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
localedata/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
(all): Remove target.
nptl/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
nptl_db/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
To make future improvements of allocator simpler we could for now calloc
just call malloc and memset. With that we could omit a changes that
would duplicate malloc changes anyway.
Remove an unused #define and use ANSI prototypes.
Generated code identical on x86_64-unknown-linux-gnu.
ChangeLog:
2014-02-11 Will Newton <will.newton@linaro.org>
* malloc/mtrace.c (attribute_hidden): Remove unused macro
definition. (tr_where, tr_freehook, tr_mallochook,
tr_reallochook, tr_memalignhook): Use ANSI protoype.
Perform sanity check only if we have_lock. Due to lockless nature of fastbins
we need to be careful derefencing pointers to fastbin entries (chunksize(old)
in this case) in multithreaded environments.
The fix is to add have_lock to the if-condition checks. The rest of the patch
only makes code more readable.
* malloc/malloc.c (_int_free): Perform sanity check only if we
have_lock.
As detailed in PR11157, the use of '__block' is known to interfere
with keywords in some environments, such as the Clang -fblocks extension.
Recently a similar issue was raised concerning the use of '__unused'
and a '__glibc' prefix was proposed to create a glibc implementation
namespace for these sorts of issues [1]. This patches takes that
approach.
[1] https://sourceware.org/ml/libc-alpha/2012-02/msg00047.html
[2] http://lists.debian.org/debian-glibc/2013/11/msg00020.html
A very large alignment argument passed to mealign/posix_memalign
causes _int_memalign to enter an infinite loop. Limit the maximum
alignment value to the maximum representable power of two to
prevent this from happening.
Changelog:
2013-10-30 Will Newton <will.newton@linaro.org>
[BZ #16038]
* malloc/hooks.c (memalign_check): Limit alignment to the
maximum representable power of two.
* malloc/malloc.c (__libc_memalign): Likewise.
* malloc/tst-memalign.c (do_test): Add test for very
large alignment values.
* malloc/tst-posix_memalign.c (do_test): Likewise.
Autoconf has been deprecating configure.in for quite a long time.
Rename all our configure.in and preconfigure.in files to .ac.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
A large value of bytes passed to memalign_check can cause an integer
overflow in _int_memalign and heap corruption. This issue can be
exposed by running tst-memalign with MALLOC_CHECK_=3.
ChangeLog:
2013-10-10 Will Newton <will.newton@linaro.org>
* malloc/hooks.c (memalign_check): Ensure the value of bytes
passed to _int_memalign does not overflow.
Add some comments and call free on all potentially allocated pointers.
Also remove duplicate check for NULL pointer.
ChangeLog:
2013-10-04 Will Newton <will.newton@linaro.org>
* malloc/tst-valloc.c: Add comments.
(do_test): Add comments and call free on all potentially
allocated pointers. Remove duplicate check for NULL pointer.
Add space after cast.
Add some comments and call free on all potentially allocated pointers.
Also remove duplicate check for NULL pointer.
ChangeLog:
2013-10-04 Will Newton <will.newton@linaro.org>
* malloc/tst-pvalloc.c: Add comments.
(do_test): Add comments and call free on all potentially
allocated pointers. Remove duplicate check for NULL pointer.
Add space after cast.
Add some comments and call free on all potentially allocated pointers.
ChangeLog:
2013-10-04 Will Newton <will.newton@linaro.org>
* malloc/tst-posix_memalign.c: Add comments.
(do_test): Add comments and call free on all potentially
allocated pointers. Add space after cast.
for ChangeLog
* malloc/arena.c (new_heap): New memory_heap_new probe.
(grow_heap): New memory_heap_more probe.
(shrink_heap): New memory_heap_less probe.
(heap_trim): New memory_heap_free probe.
* malloc/malloc.c (sysmalloc): New memory_sbrk_more probe.
(systrim): New memory_sbrk_less probe.
* manual/probes.texi: Document them.
A large bytes parameter to memalign could cause an integer overflow
and corrupt allocator internals. Check the overflow does not occur
before continuing with the allocation.
ChangeLog:
2013-09-11 Will Newton <will.newton@linaro.org>
[BZ #15857]
* malloc/malloc.c (__libc_memalign): Check the value of bytes
does not overflow.
A large bytes parameter to valloc could cause an integer overflow
and corrupt allocator internals. Check the overflow does not occur
before continuing with the allocation.
ChangeLog:
2013-09-11 Will Newton <will.newton@linaro.org>
[BZ #15856]
* malloc/malloc.c (__libc_valloc): Check the value of bytes
does not overflow.
A large bytes parameter to pvalloc could cause an integer overflow
and corrupt allocator internals. Check the overflow does not occur
before continuing with the allocation.
ChangeLog:
2013-09-11 Will Newton <will.newton@linaro.org>
[BZ #15855]
* malloc/malloc.c (__libc_pvalloc): Check the value of bytes
does not overflow.
The current tests don't test the functionality of realloc in detail.
Add a new test for realloc that exercises some of the corner cases
that are not otherwise tested.
ChangeLog:
2013-09-09 Will Newton <will.newton@linaro.org>
* malloc/Makefile: Add tst-realloc to tests.
* malloc/tst-realloc.c: New file.
it is impossible to create an alias of a common symbol (as
compat_symbol does), because common symbols do not have a section or
an offset until linked. GNU as tolerates aliases of common symbols by
simply creating another common symbol, but other assemblers (notably
LLVM's integrated assembler) are less tolerant.
2013-05-15 Peter Collingbourne <pcc@google.com>
* malloc/obstack.c (_obstack_compat): Add initializer.
-
Introduce (only on Linux) and use a HAVE_MREMAP symbol to advertize mremap
availability.
Move the malloc-sysdep.h include from arena.c to malloc.c, since what is
provided by malloc-sysdep.h is needed earlier in malloc.c, before the inclusion
of arena.c.
fclose will call free, invoking its hook, then fprintf which would indirectly
try to allocate a buffer, and this can cause malloc to be used (thus its hook
to be invoked) if libio uses malloc instead of mmap; given any malloc/free hook
locks the internal lock, this leads to a deadlock.
To prevent this hook roundtrip at muntrace, first unset MALLSTREAM and the
hooks, and only after that close the trace file.
Using madvise with MADV_DONTNEED to release memory back to the kernel
is not sufficient to change the commit charge accounted against the
process on Linux. It is OK however, when overcommit is enabled or is
heuristic. However, when overcommit is restricted to a percentage of
memory setting the contents of /proc/sys/vm/overcommit_memory as 2, it
makes a difference since memory requests will fail. Hence, we do what
we do with secure exec binaries, which is to call mmap on the region
to be dropped with MAP_FIXED. This internally unmaps the pages in
question and reduces the amount of memory accounted against the
process.
[BZ #1349]
malloc_usable_size returns the usable size in an allocated chunk,
which may be >= the requested size. In the case of MALLOC_CHECK_ being
exported to > 0 however, only the requested size is usable, since a
magic value is written at the end of the request size to trap writes
beyond request bounds. Hence, when MALLOC_CHECK_ is exported to > 0,
malloc_usable_size() should return the request size.
