1 /* Pthread mutex tunable parameters. 2 Copyright (C) 2018-2021 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 #if HAVE_TUNABLES 20 # define TUNABLE_NAMESPACE pthread 21 #include <pthread_mutex_conf.h> 22 #include <stdint.h> 23 #include <stdbool.h> 24 #include <unistd.h> /* Get STDOUT_FILENO for _dl_printf. */ 25 #include <elf/dl-tunables.h> 26 #include <nptl-stack.h> 27 28 struct mutex_config __mutex_aconf = 29 { 30 /* The maximum number of times a thread should spin on the lock before 31 calling into kernel to block. */ 32 .spin_count = DEFAULT_ADAPTIVE_COUNT, 33 }; libc_hidden_data_def(__mutex_aconf)34libc_hidden_data_def (__mutex_aconf) 35 36 static void 37 TUNABLE_CALLBACK (set_mutex_spin_count) (tunable_val_t *valp) 38 { 39 __mutex_aconf.spin_count = (int32_t) (valp)->numval; 40 } 41 42 static void TUNABLE_CALLBACK(set_stack_cache_size)43TUNABLE_CALLBACK (set_stack_cache_size) (tunable_val_t *valp) 44 { 45 __nptl_stack_cache_maxsize = valp->numval; 46 } 47 48 void __pthread_tunables_init(void)49__pthread_tunables_init (void) 50 { 51 TUNABLE_GET (mutex_spin_count, int32_t, 52 TUNABLE_CALLBACK (set_mutex_spin_count)); 53 TUNABLE_GET (stack_cache_size, size_t, 54 TUNABLE_CALLBACK (set_stack_cache_size)); 55 } 56 #endif 57