From 44b53ad6818de344e0b499ad8fdbb21fcb0ff2b6 Mon Sep 17 00:00:00 2001 From: Elliott Hughes Date: Mon, 11 Feb 2013 20:18:47 +0000 Subject: [PATCH] Revert "Revert "Pull the pthread_key_t functions out of pthread.c."" This reverts commit 6260553d48f6fd87ca220270bea8bafdde5726ec (Removing the accidental libm/Android.mk change.) Change-Id: I6cddd9857c31facc05636e8221505b3d2344cb75 --- libc/Android.mk | 9 +- libc/bionic/pthread.c | 304 +-------------------------------- libc/bionic/pthread_internal.h | 5 + libc/bionic/pthread_key.cpp | 280 ++++++++++++++++++++++++++++++ libc/bionic/sysconf.cpp | 12 +- libc/include/sys/limits.h | 6 + libc/private/bionic_tls.h | 24 ++- tests/pthread_test.cpp | 19 +++ 8 files changed, 336 insertions(+), 323 deletions(-) create mode 100644 libc/bionic/pthread_key.cpp diff --git a/libc/Android.mk b/libc/Android.mk index c7828cfd6..d21878ae8 100644 --- a/libc/Android.mk +++ b/libc/Android.mk @@ -406,7 +406,8 @@ libc_common_src_files += \ bionic/ptrace.c.arm libc_static_common_src_files += \ - bionic/pthread.c.arm \ + bionic/pthread.c.arm \ + bionic/pthread_key.cpp.arm \ # these are used by the static and dynamic versions of the libc # respectively @@ -446,7 +447,8 @@ libc_common_src_files += \ bionic/ptrace.c libc_static_common_src_files += \ - bionic/pthread.c \ + bionic/pthread.c \ + bionic/pthread_key.cpp \ libc_arch_static_src_files := \ bionic/dl_iterate_phdr_static.c @@ -492,7 +494,8 @@ libc_common_src_files += \ bionic/ptrace.c libc_static_common_src_files += \ - bionic/pthread.c + bionic/pthread.c + bionic/pthread_key.cpp \ libc_arch_static_src_files := \ bionic/dl_iterate_phdr_static.c diff --git a/libc/bionic/pthread.c b/libc/bionic/pthread.c index 88a972d3c..e1ace7dc2 100644 --- a/libc/bionic/pthread.c +++ b/libc/bionic/pthread.c @@ -101,8 +101,8 @@ static const pthread_attr_t gDefaultPthreadAttr = { .sched_priority = 0 }; -static pthread_internal_t* gThreadList = NULL; -static pthread_mutex_t gThreadListLock = PTHREAD_MUTEX_INITIALIZER; +__LIBC_HIDDEN__ pthread_internal_t* gThreadList = NULL; +__LIBC_HIDDEN__ pthread_mutex_t gThreadListLock = PTHREAD_MUTEX_INITIALIZER; static pthread_mutex_t gDebuggerNotificationLock = PTHREAD_MUTEX_INITIALIZER; static void _pthread_internal_remove_locked(pthread_internal_t* thread) { @@ -550,9 +550,6 @@ void __pthread_cleanup_pop( __pthread_cleanup_t* c, int execute ) c->__cleanup_routine(c->__cleanup_arg); } -/* used by pthread_exit() to clean all TLS keys of the current thread */ -static void pthread_key_clean_all(void); - void pthread_exit(void * retval) { pthread_internal_t* thread = __get_thread(); @@ -1780,303 +1777,6 @@ int pthread_cond_timeout_np(pthread_cond_t *cond, } - -/* A technical note regarding our thread-local-storage (TLS) implementation: - * - * There can be up to TLSMAP_SIZE independent TLS keys in a given process, - * though the first TLSMAP_START keys are reserved for Bionic to hold - * special thread-specific variables like errno or a pointer to - * the current thread's descriptor. - * - * while stored in the TLS area, these entries cannot be accessed through - * pthread_getspecific() / pthread_setspecific() and pthread_key_delete() - * - * also, some entries in the key table are pre-allocated (see tlsmap_lock) - * to greatly simplify and speedup some OpenGL-related operations. though the - * initialy value will be NULL on all threads. - * - * you can use pthread_getspecific()/setspecific() on these, and in theory - * you could also call pthread_key_delete() as well, though this would - * probably break some apps. - * - * The 'tlsmap_t' type defined below implements a shared global map of - * currently created/allocated TLS keys and the destructors associated - * with them. You should use tlsmap_lock/unlock to access it to avoid - * any race condition. - * - * the global TLS map simply contains a bitmap of allocated keys, and - * an array of destructors. - * - * each thread has a TLS area that is a simple array of TLSMAP_SIZE void* - * pointers. the TLS area of the main thread is stack-allocated in - * __libc_init_common, while the TLS area of other threads is placed at - * the top of their stack in pthread_create. - * - * when pthread_key_create() is called, it finds the first free key in the - * bitmap, then set it to 1, saving the destructor altogether - * - * when pthread_key_delete() is called. it will erase the key's bitmap bit - * and its destructor, and will also clear the key data in the TLS area of - * all created threads. As mandated by Posix, it is the responsability of - * the caller of pthread_key_delete() to properly reclaim the objects that - * were pointed to by these data fields (either before or after the call). - * - */ - -/* TLS Map implementation - */ - -#define TLSMAP_START (TLS_SLOT_MAX_WELL_KNOWN+1) -#define TLSMAP_SIZE BIONIC_TLS_SLOTS -#define TLSMAP_BITS 32 -#define TLSMAP_WORDS ((TLSMAP_SIZE+TLSMAP_BITS-1)/TLSMAP_BITS) -#define TLSMAP_WORD(m,k) (m)->map[(k)/TLSMAP_BITS] -#define TLSMAP_MASK(k) (1U << ((k)&(TLSMAP_BITS-1))) - -/* this macro is used to quickly check that a key belongs to a reasonable range */ -#define TLSMAP_VALIDATE_KEY(key) \ - ((key) >= TLSMAP_START && (key) < TLSMAP_SIZE) - -/* the type of tls key destructor functions */ -typedef void (*tls_dtor_t)(void*); - -typedef struct { - int init; /* see comment in tlsmap_lock() */ - uint32_t map[TLSMAP_WORDS]; /* bitmap of allocated keys */ - tls_dtor_t dtors[TLSMAP_SIZE]; /* key destructors */ -} tlsmap_t; - -static pthread_mutex_t _tlsmap_lock = PTHREAD_MUTEX_INITIALIZER; -static tlsmap_t _tlsmap; - -/* lock the global TLS map lock and return a handle to it */ -static __inline__ tlsmap_t* tlsmap_lock(void) -{ - tlsmap_t* m = &_tlsmap; - - pthread_mutex_lock(&_tlsmap_lock); - /* we need to initialize the first entry of the 'map' array - * with the value TLS_DEFAULT_ALLOC_MAP. doing it statically - * when declaring _tlsmap is a bit awkward and is going to - * produce warnings, so do it the first time we use the map - * instead - */ - if (__unlikely(!m->init)) { - TLSMAP_WORD(m,0) = TLS_DEFAULT_ALLOC_MAP; - m->init = 1; - } - return m; -} - -/* unlock the global TLS map */ -static __inline__ void tlsmap_unlock(tlsmap_t* m) -{ - pthread_mutex_unlock(&_tlsmap_lock); - (void)m; /* a good compiler is a happy compiler */ -} - -/* test to see wether a key is allocated */ -static __inline__ int tlsmap_test(tlsmap_t* m, int key) -{ - return (TLSMAP_WORD(m,key) & TLSMAP_MASK(key)) != 0; -} - -/* set the destructor and bit flag on a newly allocated key */ -static __inline__ void tlsmap_set(tlsmap_t* m, int key, tls_dtor_t dtor) -{ - TLSMAP_WORD(m,key) |= TLSMAP_MASK(key); - m->dtors[key] = dtor; -} - -/* clear the destructor and bit flag on an existing key */ -static __inline__ void tlsmap_clear(tlsmap_t* m, int key) -{ - TLSMAP_WORD(m,key) &= ~TLSMAP_MASK(key); - m->dtors[key] = NULL; -} - -/* allocate a new TLS key, return -1 if no room left */ -static int tlsmap_alloc(tlsmap_t* m, tls_dtor_t dtor) -{ - int key; - - for ( key = TLSMAP_START; key < TLSMAP_SIZE; key++ ) { - if ( !tlsmap_test(m, key) ) { - tlsmap_set(m, key, dtor); - return key; - } - } - return -1; -} - - -int pthread_key_create(pthread_key_t *key, void (*destructor_function)(void *)) -{ - uint32_t err = ENOMEM; - tlsmap_t* map = tlsmap_lock(); - int k = tlsmap_alloc(map, destructor_function); - - if (k >= 0) { - *key = k; - err = 0; - } - tlsmap_unlock(map); - return err; -} - - -/* This deletes a pthread_key_t. note that the standard mandates that this does - * not call the destructor of non-NULL key values. Instead, it is the - * responsibility of the caller to properly dispose of the corresponding data - * and resources, using any means it finds suitable. - * - * On the other hand, this function will clear the corresponding key data - * values in all known threads. this prevents later (invalid) calls to - * pthread_getspecific() to receive invalid/stale values. - */ -int pthread_key_delete(pthread_key_t key) -{ - uint32_t err; - pthread_internal_t* thr; - tlsmap_t* map; - - if (!TLSMAP_VALIDATE_KEY(key)) { - return EINVAL; - } - - map = tlsmap_lock(); - - if (!tlsmap_test(map, key)) { - err = EINVAL; - goto err1; - } - - /* clear value in all threads */ - pthread_mutex_lock(&gThreadListLock); - for ( thr = gThreadList; thr != NULL; thr = thr->next ) { - /* avoid zombie threads with a negative 'join_count'. these are really - * already dead and don't have a TLS area anymore. - * - * similarly, it is possible to have thr->tls == NULL for threads that - * were just recently created through pthread_create() but whose - * startup trampoline (__thread_entry) hasn't been run yet by the - * scheduler. thr->tls will also be NULL after it's stack has been - * unmapped but before the ongoing pthread_join() is finished. - * so check for this too. - */ - if (thr->join_count < 0 || !thr->tls) - continue; - - thr->tls[key] = NULL; - } - tlsmap_clear(map, key); - - pthread_mutex_unlock(&gThreadListLock); - err = 0; - -err1: - tlsmap_unlock(map); - return err; -} - - -int pthread_setspecific(pthread_key_t key, const void *ptr) -{ - int err = EINVAL; - tlsmap_t* map; - - if (TLSMAP_VALIDATE_KEY(key)) { - /* check that we're trying to set data for an allocated key */ - map = tlsmap_lock(); - if (tlsmap_test(map, key)) { - ((uint32_t *)__get_tls())[key] = (uint32_t)ptr; - err = 0; - } - tlsmap_unlock(map); - } - return err; -} - -void * pthread_getspecific(pthread_key_t key) -{ - if (!TLSMAP_VALIDATE_KEY(key)) { - return NULL; - } - - /* for performance reason, we do not lock/unlock the global TLS map - * to check that the key is properly allocated. if the key was not - * allocated, the value read from the TLS should always be NULL - * due to pthread_key_delete() clearing the values for all threads. - */ - return (void *)(((unsigned *)__get_tls())[key]); -} - -/* Posix mandates that this be defined in but we don't have - * it just yet. - */ -#ifndef PTHREAD_DESTRUCTOR_ITERATIONS -# define PTHREAD_DESTRUCTOR_ITERATIONS 4 -#endif - -/* this function is called from pthread_exit() to remove all TLS key data - * from this thread's TLS area. this must call the destructor of all keys - * that have a non-NULL data value (and a non-NULL destructor). - * - * because destructors can do funky things like deleting/creating other - * keys, we need to implement this in a loop - */ -static void pthread_key_clean_all(void) -{ - tlsmap_t* map; - void** tls = (void**)__get_tls(); - int rounds = PTHREAD_DESTRUCTOR_ITERATIONS; - - map = tlsmap_lock(); - - for (rounds = PTHREAD_DESTRUCTOR_ITERATIONS; rounds > 0; rounds--) - { - int kk, count = 0; - - for (kk = TLSMAP_START; kk < TLSMAP_SIZE; kk++) { - if ( tlsmap_test(map, kk) ) - { - void* data = tls[kk]; - tls_dtor_t dtor = map->dtors[kk]; - - if (data != NULL && dtor != NULL) - { - /* we need to clear the key data now, this will prevent the - * destructor (or a later one) from seeing the old value if - * it calls pthread_getspecific() for some odd reason - * - * we do not do this if 'dtor == NULL' just in case another - * destructor function might be responsible for manually - * releasing the corresponding data. - */ - tls[kk] = NULL; - - /* because the destructor is free to call pthread_key_create - * and/or pthread_key_delete, we need to temporarily unlock - * the TLS map - */ - tlsmap_unlock(map); - (*dtor)(data); - map = tlsmap_lock(); - - count += 1; - } - } - } - - /* if we didn't call any destructor, there is no need to check the - * TLS data again - */ - if (count == 0) - break; - } - tlsmap_unlock(map); -} - // man says this should be in , but it isn't extern int tgkill(int tgid, int tid, int sig); diff --git a/libc/bionic/pthread_internal.h b/libc/bionic/pthread_internal.h index bc682917d..24b420cf7 100644 --- a/libc/bionic/pthread_internal.h +++ b/libc/bionic/pthread_internal.h @@ -60,6 +60,11 @@ int _init_thread(pthread_internal_t* thread, pid_t kernel_id, const pthread_attr void _pthread_internal_add( pthread_internal_t* thread ); pthread_internal_t* __get_thread(void); +__LIBC_HIDDEN__ void pthread_key_clean_all(void); + +extern pthread_internal_t* gThreadList; +extern pthread_mutex_t gThreadListLock; + /* needed by posix-timers.c */ static __inline__ void timespec_add( struct timespec* a, const struct timespec* b ) diff --git a/libc/bionic/pthread_key.cpp b/libc/bionic/pthread_key.cpp new file mode 100644 index 000000000..00dacba96 --- /dev/null +++ b/libc/bionic/pthread_key.cpp @@ -0,0 +1,280 @@ +/* + * Copyright (C) 2008 The Android Open Source Project + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "bionic_atomic_inline.h" +#include "bionic_futex.h" +#include "bionic_pthread.h" +#include "bionic_ssp.h" +#include "bionic_tls.h" +#include "debug_format.h" +#include "pthread_internal.h" +#include "thread_private.h" + +/* A technical note regarding our thread-local-storage (TLS) implementation: + * + * There can be up to BIONIC_TLS_SLOTS independent TLS keys in a given process, + * The keys below TLS_SLOT_FIRST_USER_SLOT are reserved for Bionic to hold + * special thread-specific variables like errno or a pointer to + * the current thread's descriptor. These entries cannot be accessed through + * pthread_getspecific() / pthread_setspecific() or pthread_key_delete() + * + * The 'tls_map_t' type defined below implements a shared global map of + * currently created/allocated TLS keys and the destructors associated + * with them. + * + * The global TLS map simply contains a bitmap of allocated keys, and + * an array of destructors. + * + * Each thread has a TLS area that is a simple array of BIONIC_TLS_SLOTS void* + * pointers. the TLS area of the main thread is stack-allocated in + * __libc_init_common, while the TLS area of other threads is placed at + * the top of their stack in pthread_create. + * + * When pthread_key_delete() is called it will erase the key's bitmap bit + * and its destructor, and will also clear the key data in the TLS area of + * all created threads. As mandated by Posix, it is the responsibility of + * the caller of pthread_key_delete() to properly reclaim the objects that + * were pointed to by these data fields (either before or after the call). + */ + +#define TLSMAP_BITS 32 +#define TLSMAP_WORDS ((BIONIC_TLS_SLOTS+TLSMAP_BITS-1)/TLSMAP_BITS) +#define TLSMAP_WORD(m,k) (m).map[(k)/TLSMAP_BITS] +#define TLSMAP_MASK(k) (1U << ((k)&(TLSMAP_BITS-1))) + +static inline bool IsValidUserKey(pthread_key_t key) { + return (key >= TLS_SLOT_FIRST_USER_SLOT && key < BIONIC_TLS_SLOTS); +} + +typedef void (*key_destructor_t)(void*); + +struct tls_map_t { + bool is_initialized; + + /* bitmap of allocated keys */ + uint32_t map[TLSMAP_WORDS]; + + key_destructor_t key_destructors[BIONIC_TLS_SLOTS]; +}; + +class ScopedTlsMapAccess { + public: + ScopedTlsMapAccess() { + Lock(); + + // If this is the first time the TLS map has been accessed, + // mark the slots belonging to well-known keys as being in use. + // This isn't currently necessary because the well-known keys + // can only be accessed directly by bionic itself, do not have + // destructors, and all the functions that touch the TLS map + // start after the maximum well-known slot. + if (!s_tls_map_.is_initialized) { + for (pthread_key_t key = 0; key < TLS_SLOT_FIRST_USER_SLOT; ++key) { + SetInUse(key, NULL); + } + s_tls_map_.is_initialized = true; + } + } + + ~ScopedTlsMapAccess() { + Unlock(); + } + + int CreateKey(pthread_key_t* result, void (*key_destructor)(void*)) { + // Take the first unallocated key. + for (int key = 0; key < BIONIC_TLS_SLOTS; ++key) { + if (!IsInUse(key)) { + SetInUse(key, key_destructor); + *result = key; + return 0; + } + } + + // We hit PTHREAD_KEYS_MAX. POSIX says EAGAIN for this case. + return EAGAIN; + } + + void DeleteKey(pthread_key_t key) { + TLSMAP_WORD(s_tls_map_, key) &= ~TLSMAP_MASK(key); + s_tls_map_.key_destructors[key] = NULL; + } + + bool IsInUse(pthread_key_t key) { + return (TLSMAP_WORD(s_tls_map_, key) & TLSMAP_MASK(key)) != 0; + } + + void SetInUse(pthread_key_t key, void (*key_destructor)(void*)) { + TLSMAP_WORD(s_tls_map_, key) |= TLSMAP_MASK(key); + s_tls_map_.key_destructors[key] = key_destructor; + } + + // Called from pthread_exit() to remove all TLS key data + // from this thread's TLS area. This must call the destructor of all keys + // that have a non-NULL data value and a non-NULL destructor. + void CleanAll() { + void** tls = (void**)__get_tls(); + + // Because destructors can do funky things like deleting/creating other + // keys, we need to implement this in a loop. + for (int rounds = PTHREAD_DESTRUCTOR_ITERATIONS; rounds > 0; --rounds) { + size_t called_destructor_count = 0; + for (int key = 0; key < BIONIC_TLS_SLOTS; ++key) { + if (IsInUse(key)) { + void* data = tls[key]; + void (*key_destructor)(void*) = s_tls_map_.key_destructors[key]; + + if (data != NULL && key_destructor != NULL) { + // we need to clear the key data now, this will prevent the + // destructor (or a later one) from seeing the old value if + // it calls pthread_getspecific() for some odd reason + + // we do not do this if 'key_destructor == NULL' just in case another + // destructor function might be responsible for manually + // releasing the corresponding data. + tls[key] = NULL; + + // because the destructor is free to call pthread_key_create + // and/or pthread_key_delete, we need to temporarily unlock + // the TLS map + Unlock(); + (*key_destructor)(data); + Lock(); + ++called_destructor_count; + } + } + } + + // If we didn't call any destructors, there is no need to check the TLS data again. + if (called_destructor_count == 0) { + break; + } + } + } + + private: + static tls_map_t s_tls_map_; + static pthread_mutex_t s_tls_map_lock_; + + void Lock() { + pthread_mutex_lock(&s_tls_map_lock_); + } + + void Unlock() { + pthread_mutex_unlock(&s_tls_map_lock_); + } +}; + +tls_map_t ScopedTlsMapAccess::s_tls_map_; +pthread_mutex_t ScopedTlsMapAccess::s_tls_map_lock_; + +__LIBC_HIDDEN__ void pthread_key_clean_all() { + ScopedTlsMapAccess tls_map; + tls_map.CleanAll(); +} + +int pthread_key_create(pthread_key_t* key, void (*key_destructor)(void*)) { + ScopedTlsMapAccess tls_map; + return tls_map.CreateKey(key, key_destructor); +} + +// Deletes a pthread_key_t. note that the standard mandates that this does +// not call the destructors for non-NULL key values. Instead, it is the +// responsibility of the caller to properly dispose of the corresponding data +// and resources, using any means it finds suitable. +int pthread_key_delete(pthread_key_t key) { + ScopedTlsMapAccess tls_map; + + if (!IsValidUserKey(key) || !tls_map.IsInUse(key)) { + return EINVAL; + } + + // Clear value in all threads. + pthread_mutex_lock(&gThreadListLock); + for (pthread_internal_t* t = gThreadList; t != NULL; t = t->next) { + // Avoid zombie threads with a negative 'join_count'. These are really + // already dead and don't have a TLS area anymore. + + // Similarly, it is possible to have t->tls == NULL for threads that + // were just recently created through pthread_create() but whose + // startup trampoline (__thread_entry) hasn't been run yet by the + // scheduler. t->tls will also be NULL after it's stack has been + // unmapped but before the ongoing pthread_join() is finished. + // so check for this too. + if (t->join_count < 0 || !t->tls) { + continue; + } + + t->tls[key] = NULL; + } + tls_map.DeleteKey(key); + + pthread_mutex_unlock(&gThreadListLock); + return 0; +} + +void* pthread_getspecific(pthread_key_t key) { + if (!IsValidUserKey(key)) { + return NULL; + } + + // For performance reasons, we do not lock/unlock the global TLS map + // to check that the key is properly allocated. If the key was not + // allocated, the value read from the TLS should always be NULL + // due to pthread_key_delete() clearing the values for all threads. + return (void *)(((unsigned *)__get_tls())[key]); +} + +int pthread_setspecific(pthread_key_t key, const void* ptr) { + ScopedTlsMapAccess tls_map; + + if (!IsValidUserKey(key) || !tls_map.IsInUse(key)) { + return EINVAL; + } + + ((uint32_t *)__get_tls())[key] = (uint32_t)ptr; + return 0; +} diff --git a/libc/bionic/sysconf.cpp b/libc/bionic/sysconf.cpp index 6555a66fa..f4845e162 100644 --- a/libc/bionic/sysconf.cpp +++ b/libc/bionic/sysconf.cpp @@ -55,7 +55,6 @@ /* the following depends on our implementation */ #define SYSTEM_ATEXIT_MAX 65536 /* our implementation is unlimited */ -#define SYSTEM_THREAD_KEYS_MAX BIONIC_TLS_SLOTS #define SYSTEM_THREAD_STACK_MIN 32768 /* lower values may be possible, but be conservative */ #define SYSTEM_THREAD_THREADS_MAX 2048 /* really unlimited */ @@ -302,10 +301,13 @@ int sysconf(int name) { // GETPW_R_SIZE_MAX ? case _SC_LOGIN_NAME_MAX: return SYSTEM_LOGIN_NAME_MAX; -#ifdef _POSIX_THREAD_DESTRUCTOR_ITERATIONS - case _SC_THREAD_DESTRUCTOR_ITERATIONS: return _POSIX_THREAD_DESTRUCTOR_ITERATIONS; -#endif - case _SC_THREAD_KEYS_MAX: return SYSTEM_THREAD_KEYS_MAX; + + case _SC_THREAD_DESTRUCTOR_ITERATIONS: + return _POSIX_THREAD_DESTRUCTOR_ITERATIONS; + + case _SC_THREAD_KEYS_MAX: + return (BIONIC_TLS_SLOTS - TLS_SLOT_FIRST_USER_SLOT); + case _SC_THREAD_STACK_MIN: return SYSTEM_THREAD_STACK_MIN; case _SC_THREAD_THREADS_MAX: return SYSTEM_THREAD_THREADS_MAX; case _SC_TTY_NAME_MAX: return SYSTEM_TTY_NAME_MAX; diff --git a/libc/include/sys/limits.h b/libc/include/sys/limits.h index 5b127ebb2..2d0d11ebc 100644 --- a/libc/include/sys/limits.h +++ b/libc/include/sys/limits.h @@ -175,6 +175,12 @@ #define _POSIX_SAVED_IDS 1 /* saved user ids is a Linux feature */ #define _POSIX_JOB_CONTROL 1 /* job control is a Linux feature */ +#define _POSIX_THREAD_DESTRUCTOR_ITERATIONS 4 /* the minimum mandated by POSIX */ +#define PTHREAD_DESTRUCTOR_ITERATIONS 4 +#define _POSIX_THREAD_KEYS_MAX 128 /* the minimum mandated by POSIX */ +/* TODO: our PTHREAD_KEYS_MAX is currently too low to be posix compliant! */ +#define _POSIX_THREAD_THREADS_MAX 64 /* the minimum mandated by POSIX */ +#define PTHREAD_THREADS_MAX /* bionic has no specific limit */ #endif diff --git a/libc/private/bionic_tls.h b/libc/private/bionic_tls.h index b983fbc95..edf878fb7 100644 --- a/libc/private/bionic_tls.h +++ b/libc/private/bionic_tls.h @@ -47,27 +47,25 @@ __BEGIN_DECLS #define BIONIC_TLS_SLOTS 64 /* Well-known TLS slots. What data goes in which slot is arbitrary unless otherwise noted. */ -#define TLS_SLOT_SELF 0 /* The kernel requires this specific slot for x86. */ -#define TLS_SLOT_THREAD_ID 1 -#define TLS_SLOT_ERRNO 2 +enum { + TLS_SLOT_SELF = 0, /* The kernel requires this specific slot for x86. */ + TLS_SLOT_THREAD_ID, + TLS_SLOT_ERRNO, + TLS_SLOT_OPENGL_API = 3, + TLS_SLOT_OPENGL = 4, + TLS_SLOT_STACK_GUARD = 5, /* GCC requires this specific slot for x86. */ + TLS_SLOT_DLERROR, -#define TLS_SLOT_OPENGL_API 3 -#define TLS_SLOT_OPENGL 4 - -#define TLS_SLOT_STACK_GUARD 5 /* GCC requires this specific slot for x86. */ -#define TLS_SLOT_DLERROR 6 - -#define TLS_SLOT_MAX_WELL_KNOWN TLS_SLOT_DLERROR + TLS_SLOT_FIRST_USER_SLOT /* Must come last! */ +}; /* This slot is only used to pass information from the dynamic linker to * libc.so when the C library is loaded in to memory. The C runtime init * function will then clear it. Since its use is extremely temporary, - * we reuse an existing location. + * we reuse an existing location that isn't needed during libc startup. */ #define TLS_SLOT_BIONIC_PREINIT TLS_SLOT_OPENGL_API -#define TLS_DEFAULT_ALLOC_MAP 0x0000001F - /* set the Thread Local Storage, must contain at least BIONIC_TLS_SLOTS pointers */ extern void __init_tls(void** tls, void* thread_info); diff --git a/tests/pthread_test.cpp b/tests/pthread_test.cpp index 3e144dbaa..2cf45f30d 100644 --- a/tests/pthread_test.cpp +++ b/tests/pthread_test.cpp @@ -28,6 +28,25 @@ TEST(pthread, pthread_key_create) { ASSERT_EQ(EINVAL, pthread_key_delete(key)); } +TEST(pthread, pthread_key_create_lots) { + // We can allocate _SC_THREAD_KEYS_MAX keys. + std::vector keys; + for (int i = 0; i < sysconf(_SC_THREAD_KEYS_MAX); ++i) { + pthread_key_t key; + ASSERT_EQ(0, pthread_key_create(&key, NULL)); + keys.push_back(key); + } + + // ...and that really is the maximum. + pthread_key_t key; + ASSERT_EQ(EAGAIN, pthread_key_create(&key, NULL)); + + // (Don't leak all those keys!) + for (size_t i = 0; i < keys.size(); ++i) { + ASSERT_EQ(0, pthread_key_delete(keys[i])); + } +} + static void* IdFn(void* arg) { return arg; }