glibc/nptl/descr.h

246 lines
7.1 KiB
C

/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _DESCR_H
#define _DESCR_H 1
#include <limits.h>
#include <sched.h>
#include <setjmp.h>
#include <stdbool.h>
#include <sys/types.h>
#include <hp-timing.h>
#include <list.h>
#include <lowlevellock.h>
#include <pthreaddef.h>
#include <dl-sysdep.h>
#include "../nptl_db/thread_db.h"
#include <tls.h>
#ifdef HAVE_FORCED_UNWIND
# include <unwind.h>
#endif
#define __need_res_state
#include <resolv.h>
#ifndef TCB_ALIGNMENT
# define TCB_ALIGNMENT sizeof (double)
#endif
/* 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)
/* Internal version of the buffer to store cancellation handler
information. */
struct pthread_unwind_buf
{
struct
{
__jmp_buf jmp_buf;
int mask_was_saved;
} cancel_jmp_buf[1];
union
{
/* This is the placeholder of the public version. */
void *pad[4];
struct
{
/* Pointer to the previous cleanup buffer. */
struct pthread_unwind_buf *prev;
/* Backward compatibility: state of the old-style cleanup
handler at the time of the previous new-style cleanup handler
installment. */
struct _pthread_cleanup_buffer *cleanup;
/* Cancellation type before the push call. */
int canceltype;
} data;
} priv;
};
/* Thread descriptor data structure. */
struct pthread
{
union
{
#if !TLS_DTV_AT_TP
/* This overlaps the TCB as used for TLS without threads (see tls.h). */
tcbhead_t header;
#else
struct
{
int multiple_threads;
} header;
#endif
/* This extra padding has no special purpose, and this structure layout
is private and subject to change without affecting the official ABI.
We just have it here in case it might be convenient for some
implementation-specific instrumentation hack or suchlike. */
void *__padding[16];
};
/* This descriptor's link on the `stack_used' or `__stack_user' list. */
list_t list;
/* Thread ID - which is also a 'is this thread descriptor (and
therefore stack) used' flag. */
pid_t tid;
/* List of cleanup buffers. */
struct _pthread_cleanup_buffer *cleanup;
/* Unwind information. */
struct pthread_unwind_buf *cleanup_jmp_buf;
#define HAVE_CLEANUP_JMP_BUF
/* Flags determining processing of cancellation. */
int cancelhandling;
/* Bit set if cancellation is disabled. */
#define CANCELSTATE_BIT 0
#define CANCELSTATE_BITMASK 0x01
/* Bit set if asynchronous cancellation mode is selected. */
#define CANCELTYPE_BIT 1
#define CANCELTYPE_BITMASK 0x02
/* Bit set if canceling has been initiated. */
#define CANCELING_BIT 2
#define CANCELING_BITMASK 0x04
/* Bit set if canceled. */
#define CANCELED_BIT 3
#define CANCELED_BITMASK 0x08
/* Bit set if thread is exiting. */
#define EXITING_BIT 4
#define EXITING_BITMASK 0x10
/* Bit set if thread terminated and TCB is freed. */
#define TERMINATED_BIT 5
#define TERMINATED_BITMASK 0x20
/* Mask for the rest. Helps the compiler to optimize. */
#define CANCEL_RESTMASK 0xffffffc0
#define CANCEL_ENABLED_AND_CANCELED(value) \
(((value) & (CANCELSTATE_BITMASK | CANCELED_BITMASK | EXITING_BITMASK \
| CANCEL_RESTMASK | TERMINATED_BITMASK)) == CANCELED_BITMASK)
#define CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS(value) \
(((value) & (CANCELSTATE_BITMASK | CANCELTYPE_BITMASK | CANCELED_BITMASK \
| EXITING_BITMASK | CANCEL_RESTMASK | TERMINATED_BITMASK)) \
== (CANCELTYPE_BITMASK | CANCELED_BITMASK))
/* We allocate one block of references here. This should be enough
to avoid allocating any memory dynamically for most applications. */
struct pthread_key_data
{
/* Sequence number. We use uintptr_t to not require padding on
32- and 64-bit machines. On 64-bit machines it helps to avoid
wrapping, too. */
uintptr_t seq;
/* Data pointer. */
void *data;
} specific_1stblock[PTHREAD_KEY_2NDLEVEL_SIZE];
/* Flag which is set when specific data is set. */
bool specific_used;
/* Two-level array for the thread-specific data. */
struct pthread_key_data *specific[PTHREAD_KEY_1STLEVEL_SIZE];
/* Process ID - thread group ID in kernel speak. */
pid_t pid;
/* True if events must be reported. */
bool report_events;
/* True if the user provided the stack. */
bool user_stack;
/* Lock to synchronize access to the descriptor. */
lll_lock_t lock;
#if HP_TIMING_AVAIL
/* Offset of the CPU clock at start thread start time. */
hp_timing_t cpuclock_offset;
#endif
/* If the thread waits to join another one the ID of the latter is
stored here.
In case a thread is detached this field contains a pointer of the
TCB if the thread itself. This is something which cannot happen
in normal operation. */
struct pthread *joinid;
/* Check whether a thread is detached. */
#define IS_DETACHED(pd) ((pd)->joinid == (pd))
/* Flags. Including those copied from the thread attribute. */
int flags;
/* The result of the thread function. */
void *result;
/* Scheduling parameters for the new thread. */
struct sched_param schedparam;
int schedpolicy;
/* Start position of the code to be executed and the argument passed
to the function. */
void *(*start_routine) (void *);
void *arg;
/* Debug state. */
td_eventbuf_t eventbuf;
/* Next descriptor with a pending event. */
struct pthread *nextevent;
#ifdef HAVE_FORCED_UNWIND
/* Machine-specific unwind info. */
struct _Unwind_Exception exc;
#endif
/* If nonzero pointer to area allocated for the stack and its
size. */
void *stackblock;
size_t stackblock_size;
/* Size of the included guard area. */
size_t guardsize;
/* Resolver state. */
struct __res_state res;
} __attribute ((aligned (TCB_ALIGNMENT)));
#endif /* descr.h */