1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * CDDL HEADER START 4 * 5 * The contents of this file are subject to the terms of the 6 * Common Development and Distribution License (the "License"). 7 * You may not use this file except in compliance with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or https://opensource.org/licenses/CDDL-1.0. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2012, 2018 by Delphix. All rights reserved. 25 * Copyright (c) 2016 Actifio, Inc. All rights reserved. 26 * Copyright (c) 2025, Klara, Inc. 27 */ 28 29 #include <assert.h> 30 #include <pthread.h> 31 #include <string.h> 32 #include <sys/thread.h> 33 34 /* this only exists to have its address taken */ 35 void p0(void) {} 36 37 /* 38 * ========================================================================= 39 * threads 40 * ========================================================================= 41 * 42 * TS_STACK_MIN is dictated by the minimum allowed pthread stack size. While 43 * TS_STACK_MAX is somewhat arbitrary, it was selected to be large enough for 44 * the expected stack depth while small enough to avoid exhausting address 45 * space with high thread counts. 46 */ 47 #define TS_STACK_MIN MAX(PTHREAD_STACK_MIN, 32768) 48 #define TS_STACK_MAX (256 * 1024) 49 50 struct zk_thread_wrapper { 51 void (*func)(void *); 52 void *arg; 53 }; 54 55 static void * 56 zk_thread_wrapper(void *arg) 57 { 58 struct zk_thread_wrapper ztw; 59 memcpy(&ztw, arg, sizeof (ztw)); 60 free(arg); 61 ztw.func(ztw.arg); 62 return (NULL); 63 } 64 65 kthread_t * 66 zk_thread_create(const char *name, void (*func)(void *), void *arg, 67 size_t stksize, int state) 68 { 69 pthread_attr_t attr; 70 pthread_t tid; 71 char *stkstr; 72 struct zk_thread_wrapper *ztw; 73 int detachstate = PTHREAD_CREATE_DETACHED; 74 75 VERIFY0(pthread_attr_init(&attr)); 76 77 if (state & TS_JOINABLE) 78 detachstate = PTHREAD_CREATE_JOINABLE; 79 80 VERIFY0(pthread_attr_setdetachstate(&attr, detachstate)); 81 82 /* 83 * We allow the default stack size in user space to be specified by 84 * setting the ZFS_STACK_SIZE environment variable. This allows us 85 * the convenience of observing and debugging stack overruns in 86 * user space. Explicitly specified stack sizes will be honored. 87 * The usage of ZFS_STACK_SIZE is discussed further in the 88 * ENVIRONMENT VARIABLES sections of the ztest(1) man page. 89 */ 90 if (stksize == 0) { 91 stkstr = getenv("ZFS_STACK_SIZE"); 92 93 if (stkstr == NULL) 94 stksize = TS_STACK_MAX; 95 else 96 stksize = MAX(atoi(stkstr), TS_STACK_MIN); 97 } 98 99 VERIFY3S(stksize, >, 0); 100 stksize = P2ROUNDUP(MAX(stksize, TS_STACK_MIN), PAGESIZE); 101 102 /* 103 * If this ever fails, it may be because the stack size is not a 104 * multiple of system page size. 105 */ 106 VERIFY0(pthread_attr_setstacksize(&attr, stksize)); 107 VERIFY0(pthread_attr_setguardsize(&attr, PAGESIZE)); 108 109 VERIFY(ztw = malloc(sizeof (*ztw))); 110 ztw->func = func; 111 ztw->arg = arg; 112 VERIFY0(pthread_create(&tid, &attr, zk_thread_wrapper, ztw)); 113 VERIFY0(pthread_attr_destroy(&attr)); 114 115 pthread_setname_np(tid, name); 116 117 return ((void *)(uintptr_t)tid); 118 } 119