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Diffstat (limited to 'libpthread/linuxthreads/internals.h')
| -rw-r--r-- | libpthread/linuxthreads/internals.h | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/internals.h b/libpthread/linuxthreads/internals.h new file mode 100644 index 000000000..933ccb5f3 --- /dev/null +++ b/libpthread/linuxthreads/internals.h @@ -0,0 +1,480 @@ +/* Linuxthreads - a simple clone()-based implementation of Posix */ +/* threads for Linux. */ +/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ +/* */ +/* This program is free software; you can redistribute it and/or */ +/* modify it under the terms of the GNU Library General Public License */ +/* as published by the Free Software Foundation; either version 2 */ +/* of the License, or (at your option) any later version. */ +/* */ +/* This program 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 Library General Public License for more details. */ + +#ifndef _INTERNALS_H +#define _INTERNALS_H 1 + +/* Internal data structures */ + +/* Includes */ + +#include <bits/libc-tsd.h> /* for _LIBC_TSD_KEY_N */ +#include <limits.h> +#include <setjmp.h> +#include <signal.h> +#include <unistd.h> +#include <sys/types.h> +#include "pt-machine.h" +#include "semaphore.h" +#include "../linuxthreads_db/thread_dbP.h" + +#ifndef THREAD_GETMEM +# define THREAD_GETMEM(descr, member) descr->member +#endif +#ifndef THREAD_GETMEM_NC +# define THREAD_GETMEM_NC(descr, member) descr->member +#endif +#ifndef THREAD_SETMEM +# define THREAD_SETMEM(descr, member, value) descr->member = (value) +#endif +#ifndef THREAD_SETMEM_NC +# define THREAD_SETMEM_NC(descr, member, value) descr->member = (value) +#endif + +/* Arguments passed to thread creation routine */ + +struct pthread_start_args { + void * (*start_routine)(void *); /* function to run */ + void * arg; /* its argument */ + sigset_t mask; /* initial signal mask for thread */ + int schedpolicy; /* initial scheduling policy (if any) */ + struct sched_param schedparam; /* initial scheduling parameters (if any) */ +}; + + +/* We keep thread specific data in a special data structure, a two-level + array. The top-level array contains pointers to dynamically allocated + arrays of a certain number of data pointers. So we can implement a + sparse array. Each dynamic second-level array has + PTHREAD_KEY_2NDLEVEL_SIZE + entries. This value shouldn't be too large. */ +#define PTHREAD_KEY_2NDLEVEL_SIZE 32 + +/* We need to address PTHREAD_KEYS_MAX key with PTHREAD_KEY_2NDLEVEL_SIZE + keys in each subarray. */ +#define PTHREAD_KEY_1STLEVEL_SIZE \ + ((PTHREAD_KEYS_MAX + PTHREAD_KEY_2NDLEVEL_SIZE - 1) \ + / PTHREAD_KEY_2NDLEVEL_SIZE) + +typedef void (*destr_function)(void *); + +struct pthread_key_struct { + int in_use; /* already allocated? */ + destr_function destr; /* destruction routine */ +}; + + +#define PTHREAD_START_ARGS_INITIALIZER { NULL, NULL, {{0, }}, 0, { 0 } } + +/* The type of thread descriptors */ + +typedef struct _pthread_descr_struct * pthread_descr; + +/* Callback interface for removing the thread from waiting on an + object if it is cancelled while waiting or about to wait. + This hold a pointer to the object, and a pointer to a function + which ``extricates'' the thread from its enqueued state. + The function takes two arguments: pointer to the wait object, + and a pointer to the thread. It returns 1 if an extrication + actually occured, and hence the thread must also be signalled. + It returns 0 if the thread had already been extricated. */ + +typedef struct _pthread_extricate_struct { + void *pu_object; + int (*pu_extricate_func)(void *, pthread_descr); +} pthread_extricate_if; + +/* Atomic counter made possible by compare_and_swap */ + +struct pthread_atomic { + long p_count; + int p_spinlock; +}; + +/* Context info for read write locks. The pthread_rwlock_info structure + is information about a lock that has been read-locked by the thread + in whose list this structure appears. The pthread_rwlock_context + is embedded in the thread context and contains a pointer to the + head of the list of lock info structures, as well as a count of + read locks that are untracked, because no info structure could be + allocated for them. */ + +struct _pthread_rwlock_t; + +typedef struct _pthread_rwlock_info { + struct _pthread_rwlock_info *pr_next; + struct _pthread_rwlock_t *pr_lock; + int pr_lock_count; +} pthread_readlock_info; + +struct _pthread_descr_struct { + pthread_descr p_nextlive, p_prevlive; + /* Double chaining of active threads */ + pthread_descr p_nextwaiting; /* Next element in the queue holding the thr */ + pthread_descr p_nextlock; /* can be on a queue and waiting on a lock */ + pthread_t p_tid; /* Thread identifier */ + int p_pid; /* PID of Unix process */ + int p_priority; /* Thread priority (== 0 if not realtime) */ + struct _pthread_fastlock * p_lock; /* Spinlock for synchronized accesses */ + int p_signal; /* last signal received */ + sigjmp_buf * p_signal_jmp; /* where to siglongjmp on a signal or NULL */ + sigjmp_buf * p_cancel_jmp; /* where to siglongjmp on a cancel or NULL */ + char p_terminated; /* true if terminated e.g. by pthread_exit */ + char p_detached; /* true if detached */ + char p_exited; /* true if the assoc. process terminated */ + void * p_retval; /* placeholder for return value */ + int p_retcode; /* placeholder for return code */ + pthread_descr p_joining; /* thread joining on that thread or NULL */ + struct _pthread_cleanup_buffer * p_cleanup; /* cleanup functions */ + char p_cancelstate; /* cancellation state */ + char p_canceltype; /* cancellation type (deferred/async) */ + char p_canceled; /* cancellation request pending */ + int * p_errnop; /* pointer to used errno variable */ + int p_errno; /* error returned by last system call */ + int * p_h_errnop; /* pointer to used h_errno variable */ + int p_h_errno; /* error returned by last netdb function */ + char * p_in_sighandler; /* stack address of sighandler, or NULL */ + char p_sigwaiting; /* true if a sigwait() is in progress */ + struct pthread_start_args p_start_args; /* arguments for thread creation */ + void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE]; /* thread-specific data */ + void * p_libc_specific[_LIBC_TSD_KEY_N]; /* thread-specific data for libc */ + int p_userstack; /* nonzero if the user provided the stack */ + void *p_guardaddr; /* address of guard area or NULL */ + size_t p_guardsize; /* size of guard area */ + pthread_descr p_self; /* Pointer to this structure */ + int p_nr; /* Index of descriptor in __pthread_handles */ + int p_report_events; /* Nonzero if events must be reported. */ + td_eventbuf_t p_eventbuf; /* Data for event. */ + struct pthread_atomic p_resume_count; /* number of times restart() was + called on thread */ + char p_woken_by_cancel; /* cancellation performed wakeup */ + pthread_extricate_if *p_extricate; /* See above */ + pthread_readlock_info *p_readlock_list; /* List of readlock info structs */ + pthread_readlock_info *p_readlock_free; /* Free list of structs */ + int p_untracked_readlock_count; /* Readlocks not tracked by list */ + /* New elements must be added at the end. */ +} __attribute__ ((aligned(32))); /* We need to align the structure so that + doubles are aligned properly. This is 8 + bytes on MIPS and 16 bytes on MIPS64. + 32 bytes might give better cache + utilization. */ + +/* The type of thread handles. */ + +typedef struct pthread_handle_struct * pthread_handle; + +struct pthread_handle_struct { + struct _pthread_fastlock h_lock; /* Fast lock for sychronized access */ + pthread_descr h_descr; /* Thread descriptor or NULL if invalid */ + char * h_bottom; /* Lowest address in the stack thread */ +}; + +/* The type of messages sent to the thread manager thread */ + +struct pthread_request { + pthread_descr req_thread; /* Thread doing the request */ + enum { /* Request kind */ + REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT, + REQ_POST, REQ_DEBUG + } req_kind; + union { /* Arguments for request */ + struct { /* For REQ_CREATE: */ + const pthread_attr_t * attr; /* thread attributes */ + void * (*fn)(void *); /* start function */ + void * arg; /* argument to start function */ + sigset_t mask; /* signal mask */ + } create; + struct { /* For REQ_FREE: */ + pthread_t thread_id; /* identifier of thread to free */ + } free; + struct { /* For REQ_PROCESS_EXIT: */ + int code; /* exit status */ + } exit; + void * post; /* For REQ_POST: the semaphore */ + } req_args; +}; + + +/* Signals used for suspend/restart and for cancellation notification. */ + +extern int __pthread_sig_restart; +extern int __pthread_sig_cancel; + +/* Signal used for interfacing with gdb */ + +extern int __pthread_sig_debug; + +/* Global array of thread handles, used for validating a thread id + and retrieving the corresponding thread descriptor. Also used for + mapping the available stack segments. */ + +extern struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX]; + +/* Descriptor of the initial thread */ + +extern struct _pthread_descr_struct __pthread_initial_thread; + +/* Descriptor of the manager thread */ + +extern struct _pthread_descr_struct __pthread_manager_thread; + +/* Descriptor of the main thread */ + +extern pthread_descr __pthread_main_thread; + +/* Limit between the stack of the initial thread (above) and the + stacks of other threads (below). Aligned on a STACK_SIZE boundary. + Initially 0, meaning that the current thread is (by definition) + the initial thread. */ + +/* For non-MMU systems also remember to stack top of the initial thread. + * This is adapted when other stacks are malloc'ed since we don't know + * the bounds a-priori. -StS */ + +extern char *__pthread_initial_thread_bos; +#ifndef __UCLIBC_HAS_MMU__ +extern char *__pthread_initial_thread_tos; +#define NOMMU_INITIAL_THREAD_BOUNDS(tos,bos) if ((tos)>=__pthread_initial_thread_bos && (bos)<=__pthread_initial_thread_tos) __pthread_initial_thread_bos = (tos)+1 +#else +#define NOMMU_INITIAL_THREAD_BOUNDS(tos,bos) /* empty */ +#endif /* __UCLIBC_HAS_MMU__ */ + + +/* Indicate whether at least one thread has a user-defined stack (if 1), + or all threads have stacks supplied by LinuxThreads (if 0). */ + +extern int __pthread_nonstandard_stacks; + +/* File descriptor for sending requests to the thread manager. + Initially -1, meaning that __pthread_initialize_manager must be called. */ + +extern int __pthread_manager_request; + +/* Other end of the pipe for sending requests to the thread manager. */ + +extern int __pthread_manager_reader; + +/* Limits of the thread manager stack. */ + +extern char *__pthread_manager_thread_bos; +extern char *__pthread_manager_thread_tos; + +/* Pending request for a process-wide exit */ + +extern int __pthread_exit_requested, __pthread_exit_code; + +/* Set to 1 by gdb if we're debugging */ + +extern volatile int __pthread_threads_debug; + +/* Globally enabled events. */ +extern volatile td_thr_events_t __pthread_threads_events; + +/* Pointer to descriptor of thread with last event. */ +extern volatile pthread_descr __pthread_last_event; + +/* Return the handle corresponding to a thread id */ + +static inline pthread_handle thread_handle(pthread_t id) +{ + return &__pthread_handles[id % PTHREAD_THREADS_MAX]; +} + +/* Validate a thread handle. Must have acquired h->h_spinlock before. */ + +static inline int invalid_handle(pthread_handle h, pthread_t id) +{ + return h->h_descr == NULL || h->h_descr->p_tid != id; +} + +/* Fill in defaults left unspecified by pt-machine.h. */ + +/* The page size we can get from the system. This should likely not be + changed by the machine file but, you never know. */ +#ifndef PAGE_SIZE +#define PAGE_SIZE (sysconf (_SC_PAGE_SIZE)) +#endif + +/* The max size of the thread stack segments. If the default + THREAD_SELF implementation is used, this must be a power of two and + a multiple of PAGE_SIZE. */ +#ifndef STACK_SIZE +#define STACK_SIZE (2 * 1024 * 1024) +#endif + +/* The initial size of the thread stack. Must be a multiple of PAGE_SIZE. */ +#ifndef INITIAL_STACK_SIZE +#define INITIAL_STACK_SIZE (4 * PAGE_SIZE) +#endif + +/* Size of the thread manager stack. The "- 32" avoids wasting space + with some malloc() implementations. */ +#ifndef THREAD_MANAGER_STACK_SIZE +#define THREAD_MANAGER_STACK_SIZE (2 * PAGE_SIZE - 32) +#endif + +/* The base of the "array" of thread stacks. The array will grow down from + here. Defaults to the calculated bottom of the initial application + stack. */ +#ifndef THREAD_STACK_START_ADDRESS +#define THREAD_STACK_START_ADDRESS __pthread_initial_thread_bos +#endif + +/* Get some notion of the current stack. Need not be exactly the top + of the stack, just something somewhere in the current frame. */ +#ifndef CURRENT_STACK_FRAME +#define CURRENT_STACK_FRAME ({ char __csf; &__csf; }) +#endif + +/* Recover thread descriptor for the current thread */ + +extern pthread_descr __pthread_find_self (void) __attribute__ ((const)); + +static inline pthread_descr thread_self (void) __attribute__ ((const)); +static inline pthread_descr thread_self (void) +{ +#ifdef THREAD_SELF + return THREAD_SELF; +#else + char *sp = CURRENT_STACK_FRAME; +#ifdef __UCLIBC_HAS_MMU__ + if (sp >= __pthread_initial_thread_bos) + return &__pthread_initial_thread; + else if (sp >= __pthread_manager_thread_bos + && sp < __pthread_manager_thread_tos) + return &__pthread_manager_thread; + else if (__pthread_nonstandard_stacks) + return __pthread_find_self(); + else + return (pthread_descr)(((unsigned long)sp | (STACK_SIZE-1))+1) - 1; +#else + /* For non-MMU we need to be more careful about the initial thread stack. + * We refine the initial thread stack bounds dynamically as we allocate + * the other stack frame such that it doesn't overlap with them. Then + * we can be sure to pick the right thread according to the current SP */ + + /* Since we allow other stack frames to be above or below, we need to + * treat this case special. When pthread_initialize() wasn't called yet, + * only the initial thread is there. */ + if (__pthread_initial_thread_bos == NULL) { + return &__pthread_initial_thread; + } + else if (sp >= __pthread_initial_thread_bos + && sp < __pthread_initial_thread_tos) { + return &__pthread_initial_thread; + } + else if (sp >= __pthread_manager_thread_bos + && sp < __pthread_manager_thread_tos) { + return &__pthread_manager_thread; + } + else { + return __pthread_find_self(); + } +#endif /* __UCLIBC_HAS_MMU__ */ +#endif +} + +/* Max number of times we must spin on a spinlock calling sched_yield(). + After MAX_SPIN_COUNT iterations, we put the calling thread to sleep. */ + +#ifndef MAX_SPIN_COUNT +#define MAX_SPIN_COUNT 50 +#endif + +/* Duration of sleep (in nanoseconds) when we can't acquire a spinlock + after MAX_SPIN_COUNT iterations of sched_yield(). + With the 2.0 and 2.1 kernels, this MUST BE > 2ms. + (Otherwise the kernel does busy-waiting for realtime threads, + giving other threads no chance to run.) */ + +#ifndef SPIN_SLEEP_DURATION +#define SPIN_SLEEP_DURATION 2000001 +#endif + +/* Debugging */ + +#ifdef DEBUG +#include <assert.h> +#define ASSERT assert +#define MSG __pthread_message +#else +#define ASSERT(x) +#define MSG(msg,arg...) +#endif + +/* Internal global functions */ + +void __pthread_destroy_specifics(void); +void __pthread_perform_cleanup(void); +int __pthread_initialize_manager(void); +void __pthread_message(char * fmt, ...); +int __pthread_manager(void *reqfd); +int __pthread_manager_event(void *reqfd); +void __pthread_manager_sighandler(int sig); +void __pthread_reset_main_thread(void); +void __fresetlockfiles(void); +void __pthread_manager_adjust_prio(int thread_prio); +void __pthread_set_own_extricate_if(pthread_descr self, pthread_extricate_if *peif); + +extern int __pthread_attr_setguardsize __P ((pthread_attr_t *__attr, + size_t __guardsize)); +extern int __pthread_attr_getguardsize __P ((__const pthread_attr_t *__attr, + size_t *__guardsize)); +extern int __pthread_attr_setstackaddr __P ((pthread_attr_t *__attr, + void *__stackaddr)); +extern int __pthread_attr_getstackaddr __P ((__const pthread_attr_t *__attr, + void **__stackaddr)); +extern int __pthread_attr_setstacksize __P ((pthread_attr_t *__attr, + size_t __stacksize)); +extern int __pthread_attr_getstacksize __P ((__const pthread_attr_t *__attr, + size_t *__stacksize)); +extern int __pthread_getconcurrency __P ((void)); +extern int __pthread_setconcurrency __P ((int __level)); +extern int __pthread_mutexattr_gettype __P ((__const pthread_mutexattr_t *__attr, + int *__kind)); +extern void __pthread_kill_other_threads_np __P ((void)); + +void __pthread_restart_old(pthread_descr th); +void __pthread_suspend_old(pthread_descr self); + +void __pthread_restart_new(pthread_descr th); +void __pthread_suspend_new(pthread_descr self); + +void __pthread_wait_for_restart_signal(pthread_descr self); + +void __pthread_init_condvar(int rt_sig_available); + +/* Global pointers to old or new suspend functions */ + +extern void (*__pthread_restart)(pthread_descr); +extern void (*__pthread_suspend)(pthread_descr); + +/* Prototypes for the function without cancelation support when the + normal version has it. */ +extern int __libc_close (int fd); +extern int __libc_nanosleep (const struct timespec *requested_time, + struct timespec *remaining); +extern ssize_t __libc_read (int fd, void *buf, size_t count); +extern pid_t __libc_waitpid (pid_t pid, int *stat_loc, int options); +extern ssize_t __libc_write (int fd, const void *buf, size_t count); + +/* Prototypes for some of the new semaphore functions. */ +extern int __new_sem_post (sem_t * sem); + +/* The functions called the signal events. */ +extern void __linuxthreads_create_event (void); +extern void __linuxthreads_death_event (void); +extern void __linuxthreads_reap_event (void); + +#endif /* internals.h */ |