Date: Fri, 29 May 2015 07:48:30 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r283690 - stable/10/lib/libthr/thread Message-ID: <201505290748.t4T7mU6k081221@svn.freebsd.org>
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Author: kib Date: Fri May 29 07:48:30 2015 New Revision: 283690 URL: https://svnweb.freebsd.org/changeset/base/283690 Log: MFC r282948: Use bare mmap(2) to allocate space for the per-thread keys, instead of malloc(). This allows third party mallocs, which use pthread_setspecific(3) on the allocation path, to work. Modified: stable/10/lib/libthr/thread/thr_spec.c Directory Properties: stable/10/ (props changed) Modified: stable/10/lib/libthr/thread/thr_spec.c ============================================================================== --- stable/10/lib/libthr/thread/thr_spec.c Fri May 29 06:45:32 2015 (r283689) +++ stable/10/lib/libthr/thread/thr_spec.c Fri May 29 07:48:30 2015 (r283690) @@ -30,6 +30,7 @@ */ #include "namespace.h" +#include <sys/mman.h> #include <signal.h> #include <stdlib.h> #include <string.h> @@ -40,7 +41,6 @@ #include "thr_private.h" -/* Static variables: */ struct pthread_key _thread_keytable[PTHREAD_KEYS_MAX]; __weak_reference(_pthread_key_create, pthread_key_create); @@ -50,7 +50,7 @@ __weak_reference(_pthread_setspecific, p int -_pthread_key_create(pthread_key_t *key, void (*destructor) (void *)) +_pthread_key_create(pthread_key_t *key, void (*destructor)(void *)) { struct pthread *curthread; int i; @@ -59,7 +59,6 @@ _pthread_key_create(pthread_key_t *key, curthread = _get_curthread(); - /* Lock the key table: */ THR_LOCK_ACQUIRE(curthread, &_keytable_lock); for (i = 0; i < PTHREAD_KEYS_MAX; i++) { @@ -68,14 +67,12 @@ _pthread_key_create(pthread_key_t *key, _thread_keytable[i].destructor = destructor; _thread_keytable[i].seqno++; - /* Unlock the key table: */ THR_LOCK_RELEASE(curthread, &_keytable_lock); *key = i + 1; return (0); } } - /* Unlock the key table: */ THR_LOCK_RELEASE(curthread, &_keytable_lock); return (EAGAIN); } @@ -83,44 +80,40 @@ _pthread_key_create(pthread_key_t *key, int _pthread_key_delete(pthread_key_t userkey) { - struct pthread *curthread = _get_curthread(); - int key = userkey - 1; - int ret = 0; - - if ((unsigned int)key < PTHREAD_KEYS_MAX) { - /* Lock the key table: */ - THR_LOCK_ACQUIRE(curthread, &_keytable_lock); - - if (_thread_keytable[key].allocated) - _thread_keytable[key].allocated = 0; - else - ret = EINVAL; - - /* Unlock the key table: */ - THR_LOCK_RELEASE(curthread, &_keytable_lock); - } else + struct pthread *curthread; + int key, ret; + + key = userkey - 1; + if ((unsigned int)key >= PTHREAD_KEYS_MAX) + return (EINVAL); + curthread = _get_curthread(); + THR_LOCK_ACQUIRE(curthread, &_keytable_lock); + if (_thread_keytable[key].allocated) { + _thread_keytable[key].allocated = 0; + ret = 0; + } else { ret = EINVAL; + } + THR_LOCK_RELEASE(curthread, &_keytable_lock); return (ret); } void _thread_cleanupspecific(void) { - struct pthread *curthread = _get_curthread(); - void (*destructor)( void *); - const void *data = NULL; - int key; - int i; + struct pthread *curthread; + void (*destructor)(void *); + const void *data; + int i, key; + curthread = _get_curthread(); if (curthread->specific == NULL) return; - - /* Lock the key table: */ THR_LOCK_ACQUIRE(curthread, &_keytable_lock); - for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) && - (curthread->specific_data_count > 0); i++) { - for (key = 0; (key < PTHREAD_KEYS_MAX) && - (curthread->specific_data_count > 0); key++) { + for (i = 0; i < PTHREAD_DESTRUCTOR_ITERATIONS && + curthread->specific_data_count > 0; i++) { + for (key = 0; key < PTHREAD_KEYS_MAX && + curthread->specific_data_count > 0; key++) { destructor = NULL; if (_thread_keytable[key].allocated && @@ -128,31 +121,29 @@ _thread_cleanupspecific(void) if (curthread->specific[key].seqno == _thread_keytable[key].seqno) { data = curthread->specific[key].data; - destructor = _thread_keytable[key].destructor; + destructor = _thread_keytable[key]. + destructor; } curthread->specific[key].data = NULL; curthread->specific_data_count--; - } - else if (curthread->specific[key].data != NULL) { + } else if (curthread->specific[key].data != NULL) { /* - * This can happen if the key is deleted via - * pthread_key_delete without first setting the value - * to NULL in all threads. POSIX says that the - * destructor is not invoked in this case. + * This can happen if the key is + * deleted via pthread_key_delete + * without first setting the value to + * NULL in all threads. POSIX says + * that the destructor is not invoked + * in this case. */ curthread->specific[key].data = NULL; curthread->specific_data_count--; } /* - * If there is a destructor, call it - * with the key table entry unlocked: + * If there is a destructor, call it with the + * key table entry unlocked. */ if (destructor != NULL) { - /* - * Don't hold the lock while calling the - * destructor: - */ THR_LOCK_RELEASE(curthread, &_keytable_lock); destructor(__DECONST(void *, data)); THR_LOCK_ACQUIRE(curthread, &_keytable_lock); @@ -160,102 +151,92 @@ _thread_cleanupspecific(void) } } THR_LOCK_RELEASE(curthread, &_keytable_lock); - free(curthread->specific); + munmap(curthread->specific, PTHREAD_KEYS_MAX * sizeof(struct + pthread_specific_elem)); curthread->specific = NULL; - if (curthread->specific_data_count > 0) + if (curthread->specific_data_count > 0) { stderr_debug("Thread %p has exited with leftover " "thread-specific data after %d destructor iterations\n", curthread, PTHREAD_DESTRUCTOR_ITERATIONS); -} - -static inline struct pthread_specific_elem * -pthread_key_allocate_data(void) -{ - struct pthread_specific_elem *new_data; - - new_data = (struct pthread_specific_elem *) - calloc(1, sizeof(struct pthread_specific_elem) * PTHREAD_KEYS_MAX); - return (new_data); + } } int _pthread_setspecific(pthread_key_t userkey, const void *value) { - struct pthread *pthread; - pthread_key_t key = userkey - 1; - int ret = 0; + struct pthread *pthread; + void *tmp; + pthread_key_t key; + + key = userkey - 1; + if ((unsigned int)key >= PTHREAD_KEYS_MAX || + !_thread_keytable[key].allocated) + return (EINVAL); - /* Point to the running thread: */ pthread = _get_curthread(); - - if ((pthread->specific) || - (pthread->specific = pthread_key_allocate_data())) { - if ((unsigned int)key < PTHREAD_KEYS_MAX) { - if (_thread_keytable[key].allocated) { - if (pthread->specific[key].data == NULL) { - if (value != NULL) - pthread->specific_data_count++; - } else if (value == NULL) - pthread->specific_data_count--; - pthread->specific[key].data = value; - pthread->specific[key].seqno = - _thread_keytable[key].seqno; - ret = 0; - } else - ret = EINVAL; - } else - ret = EINVAL; - } else - ret = ENOMEM; - return (ret); + if (pthread->specific == NULL) { + tmp = mmap(NULL, PTHREAD_KEYS_MAX * + sizeof(struct pthread_specific_elem), + PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0); + if (tmp == MAP_FAILED) + return (ENOMEM); + pthread->specific = tmp; + } + if (pthread->specific[key].data == NULL) { + if (value != NULL) + pthread->specific_data_count++; + } else if (value == NULL) + pthread->specific_data_count--; + pthread->specific[key].data = value; + pthread->specific[key].seqno = _thread_keytable[key].seqno; + return (0); } void * _pthread_getspecific(pthread_key_t userkey) { - struct pthread *pthread; - pthread_key_t key = userkey - 1; - const void *data; + struct pthread *pthread; + const void *data; + pthread_key_t key; + + /* Check if there is specific data. */ + key = userkey - 1; + if ((unsigned int)key >= PTHREAD_KEYS_MAX) + return (NULL); - /* Point to the running thread: */ pthread = _get_curthread(); - - /* Check if there is specific data: */ - if (pthread->specific != NULL && (unsigned int)key < PTHREAD_KEYS_MAX) { - /* Check if this key has been used before: */ - if (_thread_keytable[key].allocated && - (pthread->specific[key].seqno == _thread_keytable[key].seqno)) { - /* Return the value: */ - data = pthread->specific[key].data; - } else { - /* - * This key has not been used before, so return NULL - * instead: - */ - data = NULL; - } - } else - /* No specific data has been created, so just return NULL: */ + /* Check if this key has been used before. */ + if (_thread_keytable[key].allocated && pthread->specific != NULL && + pthread->specific[key].seqno == _thread_keytable[key].seqno) { + /* Return the value: */ + data = pthread->specific[key].data; + } else { + /* + * This key has not been used before, so return NULL + * instead. + */ data = NULL; + } return (__DECONST(void *, data)); } void _thr_tsd_unload(struct dl_phdr_info *phdr_info) { - struct pthread *curthread = _get_curthread(); + struct pthread *curthread; void (*destructor)(void *); int key; + curthread = _get_curthread(); THR_LOCK_ACQUIRE(curthread, &_keytable_lock); for (key = 0; key < PTHREAD_KEYS_MAX; key++) { - if (_thread_keytable[key].allocated) { - destructor = _thread_keytable[key].destructor; - if (destructor != NULL) { - if (__elf_phdr_match_addr(phdr_info, destructor)) - _thread_keytable[key].destructor = NULL; - } - } + if (!_thread_keytable[key].allocated) + continue; + destructor = _thread_keytable[key].destructor; + if (destructor == NULL) + continue; + if (__elf_phdr_match_addr(phdr_info, destructor)) + _thread_keytable[key].destructor = NULL; } THR_LOCK_RELEASE(curthread, &_keytable_lock); }
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