diff options
| -rw-r--r-- | NEWS | 4 | ||||
| -rw-r--r-- | elf/Makefile | 11 | ||||
| -rw-r--r-- | elf/dl-main.h | 2 | ||||
| -rw-r--r-- | elf/dl-tunables.c | 43 | ||||
| -rw-r--r-- | elf/dl-tunables.h | 2 | ||||
| -rw-r--r-- | elf/dl-usage.c | 7 | ||||
| -rw-r--r-- | elf/rtld.c | 19 | ||||
| -rw-r--r-- | elf/tst-rtld-list-tunables.exp | 14 | ||||
| -rwxr-xr-x | elf/tst-rtld-list-tunables.sh | 34 | ||||
| -rw-r--r-- | manual/tunables.texi | 38 |
10 files changed, 172 insertions, 2 deletions
diff --git a/NEWS b/NEWS index face78cd10..d121f7df87 100644 --- a/NEWS +++ b/NEWS @@ -9,6 +9,10 @@ Version 2.33 Major new features: +* The dynamic linker accepts the --list-tunables argument which prints + all the supported tunables. This option is disable if glibc is + configured with tunables disabled (--enable-tunables=no). + * The dynamic linker accepts the --argv0 argument and provides opportunity to change argv[0] string. diff --git a/elf/Makefile b/elf/Makefile index c41d11693b..5e7f938e2d 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -45,6 +45,10 @@ dl-routines += dl-tunables tunables-type = $(addprefix TUNABLES_FRONTEND_,$(have-tunables)) CPPFLAGS-dl-tunables.c += -DTUNABLES_FRONTEND=$(tunables-type) +ifeq (yesyes,$(build-shared)$(run-built-tests)) +tests-special += $(objpfx)list-tunables.out +endif + # Make sure that the compiler does not insert any library calls in tunables # code paths. ifeq (yes,$(have-loop-to-function)) @@ -1896,3 +1900,10 @@ $(objpfx)tst-glibc-hwcaps-mask.out: \ # Generic dependency for sysdeps implementation of # tst-glibc-hwcaps-cache. $(objpfx)tst-glibc-hwcaps-cache.out: $(objpfx)tst-glibc-hwcaps + +$(objpfx)list-tunables.out: tst-rtld-list-tunables.sh $(objpfx)ld.so + $(SHELL) $< $(objpfx)ld.so '$(test-wrapper-env)' \ + '$(run_program_env)' > $(objpfx)/tst-rtld-list-tunables.out + cmp tst-rtld-list-tunables.exp \ + $(objpfx)/tst-rtld-list-tunables.out > $@; \ + $(evaluate-test) diff --git a/elf/dl-main.h b/elf/dl-main.h index 0bccab165f..3a5e13c739 100644 --- a/elf/dl-main.h +++ b/elf/dl-main.h @@ -63,7 +63,7 @@ struct audit_list enum rtld_mode { rtld_mode_normal, rtld_mode_list, rtld_mode_verify, rtld_mode_trace, - rtld_mode_help, + rtld_mode_list_tunables, rtld_mode_help, }; /* Aggregated state information extracted from environment variables diff --git a/elf/dl-tunables.c b/elf/dl-tunables.c index 9b4d737fb8..33be00e447 100644 --- a/elf/dl-tunables.c +++ b/elf/dl-tunables.c @@ -26,6 +26,7 @@ #include <sysdep.h> #include <fcntl.h> #include <ldsodefs.h> +#include <array_length.h> #define TUNABLES_INTERNAL 1 #include "dl-tunables.h" @@ -398,6 +399,48 @@ __tunables_init (char **envp) } } +void +__tunables_print (void) +{ + for (int i = 0; i < array_length (tunable_list); i++) + { + const tunable_t *cur = &tunable_list[i]; + if (cur->type.type_code == TUNABLE_TYPE_STRING + && cur->val.strval == NULL) + _dl_printf ("%s:\n", cur->name); + else + { + _dl_printf ("%s: ", cur->name); + switch (cur->type.type_code) + { + case TUNABLE_TYPE_INT_32: + _dl_printf ("%d (min: %d, max: %d)\n", + (int) cur->val.numval, + (int) cur->type.min, + (int) cur->type.max); + break; + case TUNABLE_TYPE_UINT_64: + _dl_printf ("0x%lx (min: 0x%lx, max: 0x%lx)\n", + (long int) cur->val.numval, + (long int) cur->type.min, + (long int) cur->type.max); + break; + case TUNABLE_TYPE_SIZE_T: + _dl_printf ("0x%Zx (min: 0x%Zx, max: 0x%Zx)\n", + (size_t) cur->val.numval, + (size_t) cur->type.min, + (size_t) cur->type.max); + break; + case TUNABLE_TYPE_STRING: + _dl_printf ("%s\n", cur->val.strval); + break; + default: + __builtin_unreachable (); + } + } + } +} + /* Set the tunable value. This is called by the module that the tunable exists in. */ void diff --git a/elf/dl-tunables.h b/elf/dl-tunables.h index 518342a300..dfa16c1977 100644 --- a/elf/dl-tunables.h +++ b/elf/dl-tunables.h @@ -69,9 +69,11 @@ typedef struct _tunable tunable_t; # include "dl-tunable-list.h" extern void __tunables_init (char **); +extern void __tunables_print (void); extern void __tunable_get_val (tunable_id_t, void *, tunable_callback_t); extern void __tunable_set_val (tunable_id_t, void *, void *, void *); rtld_hidden_proto (__tunables_init) +rtld_hidden_proto (__tunables_print) rtld_hidden_proto (__tunable_get_val) rtld_hidden_proto (__tunable_set_val) diff --git a/elf/dl-usage.c b/elf/dl-usage.c index 907f068cfb..6e26818bd7 100644 --- a/elf/dl-usage.c +++ b/elf/dl-usage.c @@ -255,7 +255,12 @@ setting environment variables (which would be inherited by subprocesses).\n\ in LIST\n\ --audit LIST use objects named in LIST as auditors\n\ --preload LIST preload objects named in LIST\n\ - --argv0 STRING set argv[0] to STRING before running\n\ + --argv0 STRING set argv[0] to STRING before running\n" +#if HAVE_TUNABLES +"\ + --list-tunables list all tunables with minimum and maximum values\n" +#endif +"\ --help display this help and exit\n\ --version output version information and exit\n\ \n\ diff --git a/elf/rtld.c b/elf/rtld.c index 8d9add90e3..596b6ac3d9 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -50,6 +50,7 @@ #include <dl-main.h> #include <list.h> #include <gnu/lib-names.h> +#include <dl-tunables.h> #include <assert.h> @@ -1276,6 +1277,16 @@ dl_main (const ElfW(Phdr) *phdr, _dl_argc -= 2; _dl_argv += 2; } +#if HAVE_TUNABLES + else if (! strcmp (_dl_argv[1], "--list-tunables")) + { + state.mode = rtld_mode_list_tunables; + + ++_dl_skip_args; + --_dl_argc; + ++_dl_argv; + } +#endif else if (strcmp (_dl_argv[1], "--help") == 0) { state.mode = rtld_mode_help; @@ -1296,6 +1307,14 @@ dl_main (const ElfW(Phdr) *phdr, else break; +#if HAVE_TUNABLES + if (__glibc_unlikely (state.mode == rtld_mode_list_tunables)) + { + __tunables_print (); + _exit (0); + } +#endif + /* If we have no further argument the program was called incorrectly. Grant the user some education. */ if (_dl_argc < 2) diff --git a/elf/tst-rtld-list-tunables.exp b/elf/tst-rtld-list-tunables.exp new file mode 100644 index 0000000000..4f3f7ee4e3 --- /dev/null +++ b/elf/tst-rtld-list-tunables.exp @@ -0,0 +1,14 @@ +glibc.malloc.arena_max: 0x0 (min: 0x1, max: 0x[f]+) +glibc.malloc.arena_test: 0x0 (min: 0x1, max: 0x[f]+) +glibc.malloc.check: 0 (min: 0, max: 3) +glibc.malloc.mmap_max: 0 (min: -2147483648, max: 2147483647) +glibc.malloc.mmap_threshold: 0x0 (min: 0x0, max: 0x[f]+) +glibc.malloc.mxfast: 0x0 (min: 0x0, max: 0x[f]+) +glibc.malloc.perturb: 0 (min: 0, max: 255) +glibc.malloc.tcache_count: 0x0 (min: 0x0, max: 0x[f]+) +glibc.malloc.tcache_max: 0x0 (min: 0x0, max: 0x[f]+) +glibc.malloc.tcache_unsorted_limit: 0x0 (min: 0x0, max: 0x[f]+) +glibc.malloc.top_pad: 0x0 (min: 0x0, max: 0x[f]+) +glibc.malloc.trim_threshold: 0x0 (min: 0x0, max: 0x[f]+) +glibc.rtld.nns: 0x4 (min: 0x1, max: 0x10) +glibc.rtld.optional_static_tls: 0x200 (min: 0x0, max: 0x[f]+) diff --git a/elf/tst-rtld-list-tunables.sh b/elf/tst-rtld-list-tunables.sh new file mode 100755 index 0000000000..e7bbdde949 --- /dev/null +++ b/elf/tst-rtld-list-tunables.sh @@ -0,0 +1,34 @@ +#!/bin/sh +# Test for --list-tunables option ld.so. +# Copyright (C) 2021 Free Software Foundation, Inc. +# This file is part of the GNU C Library. +# +# The GNU C Library is free software; you can redistribute it and/or +# modify it under the terms of the GNU Lesser General Public +# License as published by the Free Software Foundation; either +# version 2.1 of the License, or (at your option) any later version. +# +# The GNU C Library is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public +# License along with the GNU C Library; if not, see +# <https://www.gnu.org/licenses/>. + +set -e + +rtld=$1 +test_wrapper_env=$2 +run_program_env=$3 + +LC_ALL=C +export LC_ALL + +${test_wrapper_env} \ +${run_program_env} \ +$rtld --list-tunables \ +| sort -u \ +| egrep "(rtld|malloc)" \ +| sed -e "s/0xf\+/0x[f]+/" diff --git a/manual/tunables.texi b/manual/tunables.texi index 1bbdc88281..1b746c0fa1 100644 --- a/manual/tunables.texi +++ b/manual/tunables.texi @@ -28,6 +28,44 @@ Finally, the set of tunables available may vary between distributions as the tunables feature allows distributions to add their own tunables under their own namespace. +Passing @option{--list-tunables} to the dynamic loader to print all +tunables with minimum and maximum values: + +@example +$ /lib64/ld-linux-x86-64.so.2 --list-tunables +glibc.rtld.nns: 0x4 (min: 0x1, max: 0x10) +glibc.elision.skip_lock_after_retries: 3 (min: -2147483648, max: 2147483647) +glibc.malloc.trim_threshold: 0x0 (min: 0x0, max: 0xffffffffffffffff) +glibc.malloc.perturb: 0 (min: 0, max: 255) +glibc.cpu.x86_shared_cache_size: 0x100000 (min: 0x0, max: 0xffffffffffffffff) +glibc.mem.tagging: 0 (min: 0, max: 255) +glibc.elision.tries: 3 (min: -2147483648, max: 2147483647) +glibc.elision.enable: 0 (min: 0, max: 1) +glibc.cpu.x86_rep_movsb_threshold: 0x1000 (min: 0x100, max: 0xffffffffffffffff) +glibc.malloc.mxfast: 0x0 (min: 0x0, max: 0xffffffffffffffff) +glibc.elision.skip_lock_busy: 3 (min: -2147483648, max: 2147483647) +glibc.malloc.top_pad: 0x0 (min: 0x0, max: 0xffffffffffffffff) +glibc.cpu.x86_rep_stosb_threshold: 0x800 (min: 0x1, max: 0xffffffffffffffff) +glibc.cpu.x86_non_temporal_threshold: 0xc0000 (min: 0x0, max: 0xffffffffffffffff) +glibc.cpu.x86_shstk: +glibc.cpu.hwcap_mask: 0x6 (min: 0x0, max: 0xffffffffffffffff) +glibc.malloc.mmap_max: 0 (min: -2147483648, max: 2147483647) +glibc.elision.skip_trylock_internal_abort: 3 (min: -2147483648, max: 2147483647) +glibc.malloc.tcache_unsorted_limit: 0x0 (min: 0x0, max: 0xffffffffffffffff) +glibc.cpu.x86_ibt: +glibc.cpu.hwcaps: +glibc.elision.skip_lock_internal_abort: 3 (min: -2147483648, max: 2147483647) +glibc.malloc.arena_max: 0x0 (min: 0x1, max: 0xffffffffffffffff) +glibc.malloc.mmap_threshold: 0x0 (min: 0x0, max: 0xffffffffffffffff) +glibc.cpu.x86_data_cache_size: 0x8000 (min: 0x0, max: 0xffffffffffffffff) +glibc.malloc.tcache_count: 0x0 (min: 0x0, max: 0xffffffffffffffff) +glibc.malloc.arena_test: 0x0 (min: 0x1, max: 0xffffffffffffffff) +glibc.pthread.mutex_spin_count: 100 (min: 0, max: 32767) +glibc.rtld.optional_static_tls: 0x200 (min: 0x0, max: 0xffffffffffffffff) +glibc.malloc.tcache_max: 0x0 (min: 0x0, max: 0xffffffffffffffff) +glibc.malloc.check: 0 (min: 0, max: 3) +@end example + @menu * Tunable names:: The structure of a tunable name * Memory Allocation Tunables:: Tunables in the memory allocation subsystem |