aboutsummaryrefslogtreecommitdiff
path: root/elf/rtld.c
AgeCommit message (Collapse)AuthorFilesLines
2021-07-14elf: Fix DTV gap reuse logic (BZ #27135)Adhemerval Zanella1-1/+1
This is updated version of the 572bd547d57a (reverted by 40ebfd016ad2) that fixes the _dl_next_tls_modid issues. This issue with 572bd547d57a patch is the DTV entry will be only update on dl_open_worker() with the update_tls_slotinfo() call after all dependencies are being processed by _dl_map_object_deps(). However _dl_map_object_deps() itself might call _dl_next_tls_modid(), and since the _dl_tls_dtv_slotinfo_list::map is not yet set the entry will be wrongly reused. This patch fixes by renaming the _dl_next_tls_modid() function to _dl_assign_tls_modid() and by passing the link_map so it can set the slotinfo value so a subsequente _dl_next_tls_modid() call will see the entry as allocated. The intermediary value is cleared up on remove_slotinfo() for the case a library fails to load with RTLD_NOW. This patch fixes BZ #27135. Checked on x86_64-linux-gnu. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2021-07-09Force building with -fno-commonFlorian Weimer1-2/+1
As a result, is not necessary to specify __attribute__ ((nocommon)) on individual definitions. GCC 10 defaults to -fno-common on all architectures except ARC, but this change is compatible with older GCC versions and ARC, too. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-10nptl: Move changing of stack permissions into ld.soFlorian Weimer1-0/+2
All the stack lists are now in _rtld_global, so it is possible to change stack permissions directly from there, instead of calling into libpthread to do the change. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-10elf: Introduce __tls_pre_init_tpFlorian Weimer1-37/+1
This is an early variant of __tls_init_tp, primarily for initializing thread-related elements of _rtld_global/GL. Some existing initialization code not needed for NPTL is moved into the generic version of this function. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-10elf, nptl: Resolve recursive lock implementation earlyFlorian Weimer1-0/+18
If libpthread is included in libc, it is not necessary to delay initialization of the lock/unlock function pointers until libpthread is loaded. This eliminates two unprotected function pointers from _rtld_global and removes some initialization code from libpthread. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-05elf, nptl: Initialize static TLS directly in ld.soFlorian Weimer1-0/+2
The stack list is available in ld.so since commit 1daccf403b1bd86370eb94edca794dc106d02039 ("nptl: Move stack list variables into _rtld_global"), so it's possible to walk the stack list directly in ld.so and perform the initialization there. This eliminates an unprotected function pointer from _rtld_global and reduces the libpthread initialization code.
2021-04-21elf: Introduce __tls_init_tp for second-phase TCB initializationFlorian Weimer1-12/+2
TLS_INIT_TP is processor-specific, so it is not a good place to put thread library initialization code (it would have to be repeated for all CPUs). Introduce __tls_init_tp as a separate function, to be called immediately after TLS_INIT_TP. Move the existing stack list setup code for NPTL to this function. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-04-21dlfcn: dlerror needs to call free from the base namespace [BZ #24773]Florian Weimer1-0/+1
Calling free directly may end up freeing a pointer allocated by the dynamic loader using malloc from libc.so in the base namespace using the allocator from libc.so in a secondary namespace, which results in crashes. This commit redirects the free call through GLRO and the dynamic linker, to reach the correct namespace. It also cleans up the dlerror handling along the way, so that pthread_setspecific is no longer needed (which avoids triggering bug 24774).
2021-04-21dlfcn: Failures after dlmopen should not terminate process [BZ #24772]Florian Weimer1-0/+1
Commit 9e78f6f6e7134a5f299cc8de77370218f8019237 ("Implement _dl_catch_error, _dl_signal_error in libc.so [BZ #16628]") has the side effect that distinct namespaces, as created by dlmopen, now have separate implementations of the rtld exception mechanism. This means that the call to _dl_catch_error from libdl in a secondary namespace does not actually install an exception handler because the thread-local variable catch_hook in the libc.so copy in the secondary namespace is distinct from that of the base namepace. As a result, a dlsym/dlopen/... failure in a secondary namespace terminates the process with a dynamic linker error because it looks to the exception handler mechanism as if no handler has been installed. This commit restores GLRO (dl_catch_error) and uses it to set the handler in the base namespace. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-03-02ld.so: Implement the --list-diagnostics optionFlorian Weimer1-6/+12
2021-01-15ld.so: Add --list-tunables to print tunable valuesH.J. Lu1-0/+19
Pass --list-tunables to ld.so to print tunables with min and max values. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-01-02Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
2020-12-15elf: Record libc.so link map when it is the main program (bug 20972)Florian Weimer1-0/+11
Otherwise, it will not participate in the dependency sorting. Fixes commit 9ffa50b26b0cb5d3043adf6d3d0b1ea735acc147 ("elf: Include libc.so.6 as main program in dependency sort (bug 20972)"). Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-12-11elf: Pass the fd to note processingSzabolcs Nagy1-2/+2
To handle GNU property notes on aarch64 some segments need to be mmaped again, so the fd of the loaded ELF module is needed. When the fd is not available (kernel loaded modules), then -1 is passed. The fd is passed to both _dl_process_pt_gnu_property and _dl_process_pt_note for consistency. Target specific note processing functions are updated accordingly. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-12-04elf: Add glibc-hwcaps support for LD_LIBRARY_PATHFlorian Weimer1-0/+18
This hacks non-power-set processing into _dl_important_hwcaps. Once the legacy hwcaps handling goes away, the subdirectory handling needs to be reworked, but it is premature to do this while both approaches are still supported. ld.so supports two new arguments, --glibc-hwcaps-prepend and --glibc-hwcaps-mask. Each accepts a colon-separated list of glibc-hwcaps subdirectory names. The prepend option adds additional subdirectories that are searched first, in the specified order. The mask option restricts the automatically selected subdirectories to those listed in the option argument. For example, on systems where /usr/lib64 is on the library search path, --glibc-hwcaps-prepend=valgrind:debug causes the dynamic loader to search the directories /usr/lib64/glibc-hwcaps/valgrind and /usr/lib64/glibc-hwcaps/debug just before /usr/lib64 is searched. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-11-16nptl: Move stack list variables into _rtld_globalFlorian Weimer1-0/+12
Now __thread_gscope_wait (the function behind THREAD_GSCOPE_WAIT, formerly __wait_lookup_done) can be implemented directly in ld.so, eliminating the unprotected GL (dl_wait_lookup_done) function pointer. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-10-13rtld: fix typo in commentRolf Eike Beer1-1/+1
2020-10-08elf: Implement ld.so --versionFlorian Weimer1-0/+2
This prints out version information for the dynamic loader and exits immediately, without further command line processing (which seems to match what some GNU tools do). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-10-08elf: Implement ld.so --helpFlorian Weimer1-8/+48
--help processing is deferred to the point where the executable has been loaded, so that it is possible to eventually include information from the main executable in the help output. As suggested in the GNU command-line interface guidelines, the help message is printed to standard output, and the exit status is successful. Handle usage errors closer to the GNU command-line interface guidelines. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-10-08elf: Record whether paths come from LD_LIBRARY_PATH or --library-pathFlorian Weimer1-0/+3
This allows more precise LD_DEBUG diagnostics. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-10-08elf: Move ld.so error/help output to _dl_usageFlorian Weimer1-25/+1
Also add a comment to elf/Makefile, explaining why we cannot use config.status for autoconf template processing. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-10-08elf: Extract command-line/environment variables state from rtld.cFlorian Weimer1-96/+59
Introduce struct dl_main_state and move it to <dl-main.h>. Rename enum mode to enum rtld_mode and add the rtld_mode_ prefix to the enum constants. This avoids the need for putting state that is only needed during startup into the ld.so data segment.
2020-09-29ld.so: add an --argv0 option [BZ #16124]Vincent Mihalkovic1-1/+16
2020-07-08rtld: Account static TLS surplus for audit modulesSzabolcs Nagy1-4/+27
The new static TLS surplus size computation is surplus_tls = 192 * (nns-1) + 144 * nns + 512 where nns is controlled via the rtld.nns tunable. This commit accounts audit modules too so nns = rtld.nns + audit modules. rtld.nns should only include the namespaces required by the application, namespaces for audit modules are accounted on top of that so audit modules don't use up the static TLS that is reserved for the application. This allows loading many audit modules without tuning rtld.nns or using up static TLS, and it fixes FAIL: elf/tst-auditmany Note that DL_NNS is currently a hard upper limit for nns, and if rtld.nns + audit modules go over the limit that's a fatal error. By default rtld.nns is 4 which allows 12 audit modules. Counting the audit modules is based on existing audit string parsing code, we cannot use GLRO(dl_naudit) before the modules are actually loaded.
2020-07-08rtld: Add rtld.nns tunable for the number of supported namespacesSzabolcs Nagy1-0/+3
TLS_STATIC_SURPLUS is 1664 bytes currently which is not enough to support DL_NNS (== 16) number of dynamic link namespaces, if we assume 192 bytes of TLS are reserved for libc use and 144 bytes are reserved for other system libraries that use IE TLS. A new tunable is introduced to control the number of supported namespaces and to adjust the surplus static TLS size as follows: surplus_tls = 192 * (rtld.nns-1) + 144 * rtld.nns + 512 The default is rtld.nns == 4 and then the surplus TLS size is the same as before, so the behaviour is unchanged by default. If an application creates more namespaces than the rtld.nns setting allows, then it is not guaranteed to work, but the limit is not checked. So existing usage will continue to work, but in the future if an application creates more than 4 dynamic link namespaces then the tunable will need to be set. In this patch DL_NNS is a fixed value and provides a maximum to the rtld.nns setting. Static linking used fixed 2048 bytes surplus TLS, this is changed so the same contract is used as for dynamic linking. With static linking DL_NNS == 1 so rtld.nns tunable is forced to 1, so by default the surplus TLS is reduced to 144 + 512 = 656 bytes. This change is not expected to cause problems. Tested on aarch64-linux-gnu and x86_64-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-07-08rtld: Clean up PT_NOTE and add PT_GNU_PROPERTY handlingSzabolcs Nagy1-4/+10
Add generic code to handle PT_GNU_PROPERTY notes. Invalid content is ignored, _dl_process_pt_gnu_property is always called after PT_LOAD segments are mapped and it has no failure modes. Currently only one NT_GNU_PROPERTY_TYPE_0 note is handled, which contains target specific properties: the _dl_process_gnu_property hook is called for each property. The old _dl_process_pt_note and _rtld_process_pt_note differ in how the program header is read. The old _dl_process_pt_note is called before PT_LOAD segments are mapped and _rtld_process_pt_note is called after PT_LOAD segments are mapped. The old _rtld_process_pt_note is removed and _dl_process_pt_note is always called after PT_LOAD segments are mapped and now it has no failure modes. The program headers are scanned backwards so that PT_NOTE can be skipped if PT_GNU_PROPERTY exists. Co-Authored-By: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-05-18x86: Move CET control to _dl_x86_feature_control [BZ #25887]H.J. Lu1-0/+2
1. Include <dl-procruntime.c> to get architecture specific initializer in rtld_global. 2. Change _dl_x86_feature_1[2] to _dl_x86_feature_1. 3. Add _dl_x86_feature_control after _dl_x86_feature_1, which is a struct of 2 bitfields for IBT and SHSTK control This fixes [BZ #25887].
2020-04-29elf: Add initial flag argument to __libc_early_initFlorian Weimer1-2/+4
The rseq initialization should happen only for the libc in the base namespace (in the dynamic case) or the statically linked libc. The __libc_multiple_libcs flag does not quite cover this case at present, so this commit introduces a flag argument to __libc_early_init, indicating whether the libc being libc is the primary one (of the main program). Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-04-24elf: Implement __libc_early_initFlorian Weimer1-0/+4
This function is defined in libc.so, and the dynamic loader calls right after relocation has been finished, before any ELF constructors or the preinit function is invoked. It is also used in the static build for initializing parts of the static libc. To locate __libc_early_init, a direct symbol lookup function is used, _dl_lookup_direct. It does not search the entire symbol scope and consults merely a single link map. This function could also be used to implement lookups in the vDSO (as an optimization). A per-namespace variable (libc_map) is added for locating libc.so, to avoid repeated traversals of the search scope. It is similar to GL(dl_initfirst). An alternative would have been to thread a context argument from _dl_open down to _dl_map_object_from_fd (where libc.so is identified). This could have avoided the global variable, but the change would be larger as a result. It would not have been possible to use this to replace GL(dl_initfirst) because that global variable is used to pass the function pointer past the stack switch from dl_main to the main program. Replacing that requires adding a new argument to _dl_init, which in turn needs changes to the architecture-specific libc.so startup code written in assembler. __libc_early_init should not be used to replace _dl_var_init (as it exists today on some architectures). Instead, _dl_lookup_direct should be used to look up a new variable symbol in libc.so, and that should then be initialized from the dynamic loader, immediately after the object has been loaded in _dl_map_object_from_fd (before relocation is run). This way, more IFUNC resolvers which depend on these variables will work. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-04-03elf: Implement DT_AUDIT, DT_DEPAUDIT support [BZ #24943]Florian Weimer1-1/+22
binutils ld has supported --audit, --depaudit for a long time, only support in glibc has been missing. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-04-03elf: Simplify handling of lists of audit stringsFlorian Weimer1-117/+112
All list elements are colon-separated strings, and there is a hard upper limit for the number of audit modules, so it is possible to pre-allocate a fixed-size array of strings to which the LD_AUDIT environment variable and --audit arguments are added. Also eliminate the global variables for the audit list because the list is only needed briefly during startup. There is a slight behavior change: All duplicate LD_AUDIT environment variables are now processed, not just the last one as before. However, such environment vectors are invalid anyway. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-02-15ld.so: Do not export free/calloc/malloc/realloc functions [BZ #25486]Florian Weimer1-0/+12
Exporting functions and relying on symbol interposition from libc.so makes the choice of implementation dependent on DT_NEEDED order, which is not what some compiler drivers expect. This commit replaces one magic mechanism (symbol interposition) with another one (preprocessor-/compiler-based redirection). This makes the hand-over from the minimal malloc to the full malloc more explicit. Removing the ABI symbols is backwards-compatible because libc.so is always in scope, and the dynamic loader will find the malloc-related symbols there since commit f0b2132b35248c1f4a80f62a2c38cddcc802aa8c ("ld.so: Support moving versioned symbols between sonames [BZ #24741]"). Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-01-03elf: Move vDSO setup to rtld (BZ#24967)Adhemerval Zanella1-1/+6
This patch moves the vDSO setup from libc to loader code, just after the vDSO link_map setup. For static case the initialization is moved to _dl_non_dynamic_init instead. Instead of using the mangled pointer, the vDSO data is set as attribute_relro (on _rtld_global_ro for shared or _dl_vdso_* for static). It is read-only even with partial relro. It fixes BZ#24967 now that the vDSO pointer is setup earlier than malloc interposition is called. Also, vDSO calls should not be a problem for static dlopen as indicated by BZ#20802. The vDSO pointer would be zero-initialized and the syscall will be issued instead. Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu, arm-linux-gnueabihf, powerpc64le-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu, s390x-linux-gnu, sparc64-linux-gnu, and sparcv9-linux-gnu. I also run some tests on mips. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2019-11-27Avoid late dlopen failure due to scope, TLS slotinfo updates [BZ #25112]Florian Weimer1-2/+2
This change splits the scope and TLS slotinfo updates in dlopen into two parts: one to resize the data structures, and one to actually apply the update. The call to add_to_global_resize in dl_open_worker is moved before the demarcation point at which no further memory allocations are allowed. _dl_add_to_slotinfo is adjusted to make the list update optional. There is some optimization possibility here because we could grow the slotinfo list of arrays in a single call, one the largest TLS modid is known. This commit does not fix the fatal meory allocation failure in _dl_update_slotinfo. Ideally, this error during dlopen should be recoverable. The update order of scopes and TLS data structures is retained, although it appears to be more correct to fully initialize TLS first, and then expose symbols in the newly loaded objects via the scope update. Tested on x86_64-linux-gnu. Change-Id: I240c58387dabda3ca1bcab48b02115175fa83d6c
2019-11-15Introduce link_map_audit_state accessor functionFlorian Weimer1-8/+10
To improve GCC 10 compatibility, it is necessary to remove the l_audit zero-length array from the end of struct link_map. In preparation of that, this commit introduces an accessor function for the audit state, so that it is possible to change the representation of the audit state without adjusting the code that accesses it. Tested on x86_64-linux-gnu. Built on i686-gnu. Change-Id: Id815673c29950fc011ae5301d7cde12624f658df
2019-11-15Properly initialize audit cookie for the dynamic loader [BZ #25157]Florian Weimer1-7/+7
The l_audit array is indexed by audit module, not audit function. Change-Id: I180eb3573dc1c57433750f5d8cb18271460ba5f2
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert1-1/+1
Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-03-22Refactor hp-timing rtld usageAdhemerval Zanella1-151/+130
This patch refactor how hp-timing is used on loader code for statistics report. The HP_TIMING_AVAIL and HP_SMALL_TIMING_AVAIL are removed and HP_TIMING_INLINE is used instead to check for hp-timing avaliability. For alpha, which only defines HP_SMALL_TIMING_AVAIL, the HP_TIMING_INLINE is set iff for IS_IN(rtld). Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu. I also checked the builds for all afected ABIs. * benchtests/bench-timing.h: Replace HP_TIMING_AVAIL with HP_TIMING_INLINE. * nptl/descr.h: Likewise. * elf/rtld.c (RLTD_TIMING_DECLARE, RTLD_TIMING_NOW, RTLD_TIMING_DIFF, RTLD_TIMING_ACCUM_NT, RTLD_TIMING_SET): Define. (dl_start_final_info, _dl_start_final, dl_main, print_statistics): Abstract hp-timing usage with RTLD_* macros. * sysdeps/alpha/hp-timing.h (HP_TIMING_INLINE): Define iff IS_IN(rtld). (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL): Remove. * sysdeps/generic/hp-timing.h (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL, HP_TIMING_NONAVAIL): Likewise. * sysdeps/ia64/hp-timing.h (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL): Likewise. * sysdeps/powerpc/powerpc32/power4/hp-timing.h (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL): Likewise. * sysdeps/powerpc/powerpc64/hp-timing.h (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL): Likewise. * sysdeps/sparc/sparc32/sparcv9/hp-timing.h (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL): Likewise. * sysdeps/sparc/sparc64/hp-timing.h (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL): Likewise. * sysdeps/x86/hp-timing.h (HP_TIMING_AVAIL, HP_SMALL_TIMING_AVAIL): Likewise. * sysdeps/generic/hp-timing-common.h: Update comment with HP_TIMING_AVAIL removal.
2019-03-22nptl: Remove pthread_clock_gettime pthread_clock_settimeAdhemerval Zanella1-2/+0
This patch removes CLOCK_THREAD_CPUTIME_ID and CLOCK_PROCESS_CPUTIME_ID support from clock_gettime and clock_settime generic implementation. For Linux, kernel already provides supports through the syscall and Hurd HTL lacks __pthread_clock_gettime and __pthread_clock_settime internal implementation. As described in clock_gettime man-page [1] on 'Historical note for SMP system', implementing CLOCK_{THREAD,PROCESS}_CPUTIME_ID with timer registers is error-prone and susceptible to timing and accurary issues that the libc can not deal without kernel support. This allows removes unused code which, however, still incur in some runtime overhead in thread creation (the struct pthread cpuclock_offset initialization). If hurd eventually wants to support them it should either either implement as a kernel facility (or something related due its architecture) or in system specific implementation. Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu. I also checked on a i686-gnu build. * nptl/Makefile (libpthread-routines): Remove pthread_clock_gettime and pthread_clock_settime. * nptl/pthreadP.h (__find_thread_by_id): Remove prototype. * elf/dl-support.c [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset): Remove. (_dl_non_dynamic_init): Remove _dl_cpuclock_offset setting. * elf/rtld.c (_dl_start_final): Likewise. * nptl/allocatestack.c (__find_thread_by_id): Remove function. * sysdeps/generic/ldsodefs.h [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset): Remove. * sysdeps/mach/hurd/dl-sysdep.c [!HP_TIMING_NOAVAIL] (_dl_cpuclock_offset): Remove. * nptl/descr.h (struct pthread): Rename cpuclock_offset to cpuclock_offset_ununsed. * nptl/nptl-init.c (__pthread_initialize_minimal_internal): Remove cpuclock_offset set. * nptl/pthread_create.c (START_THREAD_DEFN): Likewise. * sysdeps/nptl/fork.c (__libc_fork): Likewise. * nptl/pthread_clock_gettime.c: Remove file. * nptl/pthread_clock_settime.c: Likewise. * sysdeps/unix/clock_gettime.c (hp_timing_gettime): Remove function. [HP_TIMING_AVAIL] (realtime_gettime): Remove CLOCK_THREAD_CPUTIME_ID and CLOCK_PROCESS_CPUTIME_ID support. * sysdeps/unix/clock_settime.c (hp_timing_gettime): Likewise. [HP_TIMING_AVAIL] (realtime_gettime): Likewise. * sysdeps/posix/clock_getres.c (hp_timing_getres): Likewise.