mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-22 19:00:07 +00:00
b92ad8d61f
* pthread.c: Use a third signal __pthread_sig_debug distinct from __pthread_sig_cancel to notify gdb when a thread is created * manager.c: Likewise. * internals.h: Likewise. * signals.c: The implementation of sigwait(s) assumed that all signals in s have signal handlers already attached. This is not required by the standard, so make it work also if some of the signals have no handlers.
354 lines
13 KiB
C
354 lines
13 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. */
|
|
|
|
/* 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"
|
|
|
|
#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)
|
|
|
|
|
|
#define PTHREAD_START_ARGS_INITIALIZER { NULL, NULL, {{0, }}, 0, { 0 } }
|
|
|
|
/* The type of thread descriptors */
|
|
|
|
typedef struct _pthread_descr_struct * pthread_descr;
|
|
|
|
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_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 */
|
|
};
|
|
|
|
/* 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;
|
|
|
|
/* Default signals used if we don't have realtime signals */
|
|
|
|
#define DEFAULT_SIG_RESTART SIGUSR1
|
|
#define DEFAULT_SIG_CANCEL SIGUSR2
|
|
|
|
/* 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. */
|
|
|
|
extern char *__pthread_initial_thread_bos;
|
|
|
|
/* 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;
|
|
|
|
/* 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;
|
|
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;
|
|
#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);
|
|
void __pthread_manager_sighandler(int sig);
|
|
void __pthread_reset_main_thread(void);
|
|
void __fresetlockfiles(void);
|
|
void __pthread_manager_adjust_prio(int thread_prio);
|
|
|
|
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));
|
|
|
|
/* 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 int __libc_read (int fd, void *buf, size_t count);
|
|
extern pid_t __libc_waitpid (pid_t pid, int *stat_loc, int options);
|
|
extern int __libc_write (int fd, const void *buf, size_t count);
|