mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-09 04:11:27 +08:00
6c92184721
* descr.h (__pthread_find_self, thread_self): Mark as pure instead of const.
268 lines
10 KiB
C
268 lines
10 KiB
C
/* 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 _DESCR_H
|
|
#define _DESCR_H 1
|
|
|
|
#define __need_res_state
|
|
#include <resolv.h>
|
|
#include <sched.h>
|
|
#include <setjmp.h>
|
|
#include <signal.h>
|
|
#include <stdint.h>
|
|
#include <sys/types.h>
|
|
#include <hp-timing.h>
|
|
#include <tls.h>
|
|
|
|
/* Fast thread-specific data internal to libc. */
|
|
enum __libc_tsd_key_t { _LIBC_TSD_KEY_MALLOC = 0,
|
|
_LIBC_TSD_KEY_DL_ERROR,
|
|
_LIBC_TSD_KEY_RPC_VARS,
|
|
_LIBC_TSD_KEY_LOCALE,
|
|
_LIBC_TSD_KEY_CTYPE_B,
|
|
_LIBC_TSD_KEY_CTYPE_TOLOWER,
|
|
_LIBC_TSD_KEY_CTYPE_TOUPPER,
|
|
_LIBC_TSD_KEY_N };
|
|
|
|
/* The type of thread descriptors */
|
|
typedef struct _pthread_descr_struct *pthread_descr;
|
|
|
|
|
|
/* Some more includes. */
|
|
#include <pt-machine.h>
|
|
#include <linuxthreads_db/thread_dbP.h>
|
|
|
|
|
|
/* 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) */
|
|
};
|
|
|
|
|
|
/* 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;
|
|
|
|
|
|
/* 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)
|
|
|
|
|
|
union dtv;
|
|
|
|
struct _pthread_descr_struct
|
|
{
|
|
#if !defined USE_TLS || !TLS_DTV_AT_TP
|
|
/* This overlaps tcbhead_t (see tls.h), as used for TLS without threads. */
|
|
union
|
|
{
|
|
struct
|
|
{
|
|
void *tcb; /* Pointer to the TCB. This is not always
|
|
the address of this thread descriptor. */
|
|
union dtv *dtvp;
|
|
pthread_descr self; /* Pointer to this structure */
|
|
int multiple_threads;
|
|
# ifdef NEED_DL_SYSINFO
|
|
uintptr_t sysinfo;
|
|
# endif
|
|
} data;
|
|
void *__padding[16];
|
|
} p_header;
|
|
# define p_multiple_threads p_header.data.multiple_threads
|
|
#elif TLS_MULTIPLE_THREADS_IN_TCB
|
|
int p_multiple_threads;
|
|
#endif
|
|
|
|
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 */
|
|
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 */
|
|
#if !(USE_TLS && HAVE___THREAD)
|
|
void * p_libc_specific[_LIBC_TSD_KEY_N]; /* thread-specific data for libc */
|
|
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 */
|
|
struct __res_state *p_resp; /* Pointer to resolver state */
|
|
#endif
|
|
struct __res_state p_res; /* per-thread resolver state */
|
|
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 */
|
|
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 */
|
|
char p_condvar_avail; /* flag if conditional variable became avail */
|
|
char p_sem_avail; /* flag if semaphore became available */
|
|
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 */
|
|
int p_inheritsched; /* copied from the thread attribute */
|
|
#if HP_TIMING_AVAIL
|
|
hp_timing_t p_cpuclock_offset; /* Initial CPU clock for thread. */
|
|
#endif
|
|
#ifdef USE_TLS
|
|
char *p_stackaddr; /* Stack address. */
|
|
#endif
|
|
size_t p_alloca_cutoff; /* Maximum size which should be allocated
|
|
using alloca() instead of malloc(). */
|
|
/* 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. */
|
|
|
|
|
|
|
|
/* 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. */
|
|
|
|
extern char *__pthread_initial_thread_bos;
|
|
|
|
/* Descriptor of the initial thread */
|
|
|
|
extern struct _pthread_descr_struct __pthread_initial_thread;
|
|
|
|
/* Limits of the thread manager stack. */
|
|
|
|
extern char *__pthread_manager_thread_bos;
|
|
extern char *__pthread_manager_thread_tos;
|
|
|
|
/* Descriptor of the manager thread */
|
|
|
|
extern struct _pthread_descr_struct __pthread_manager_thread;
|
|
extern pthread_descr __pthread_manager_threadp attribute_hidden;
|
|
|
|
/* 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;
|
|
|
|
/* 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
|
|
|
|
/* 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__ ((pure));
|
|
|
|
static inline pthread_descr thread_self (void) __attribute__ ((pure));
|
|
static inline pthread_descr thread_self (void)
|
|
{
|
|
#ifdef THREAD_SELF
|
|
return THREAD_SELF;
|
|
#else
|
|
char *sp = CURRENT_STACK_FRAME;
|
|
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
|
|
#ifdef _STACK_GROWS_DOWN
|
|
return (pthread_descr)(((unsigned long)sp | (STACK_SIZE-1))+1) - 1;
|
|
#else
|
|
return (pthread_descr)((unsigned long)sp &~ (STACK_SIZE-1));
|
|
#endif
|
|
#endif
|
|
}
|
|
|
|
#endif /* descr.h */
|