852 lines
24 KiB
C
852 lines
24 KiB
C
/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <assert.h>
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#include <errno.h>
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#include <stdint.h>
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#include <string.h>
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#include <unistd.h>
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#include <sys/mman.h>
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#include <sys/param.h>
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#include <dl-sysdep.h>
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#include <tls.h>
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#ifndef NEED_SEPARATE_REGISTER_STACK
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/* Most architectures have exactly one stack pointer. Some have more. */
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# define STACK_VARIABLES void *stackaddr
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/* How to pass the values to the 'create_thread' function. */
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# define STACK_VARIABLES_ARGS stackaddr
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/* How to declare function which gets there parameters. */
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# define STACK_VARIABLES_PARMS void *stackaddr
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/* How to declare allocate_stack. */
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# define ALLOCATE_STACK_PARMS void **stack
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/* This is how the function is called. We do it this way to allow
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other variants of the function to have more parameters. */
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# define ALLOCATE_STACK(attr, pd) allocate_stack (attr, pd, &stackaddr)
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#else
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/* We need two stacks. The kernel will place them but we have to tell
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the kernel about the size of the reserved address space. */
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# define STACK_VARIABLES void *stackaddr; size_t stacksize
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/* How to pass the values to the 'create_thread' function. */
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# define STACK_VARIABLES_ARGS stackaddr, stacksize
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/* How to declare function which gets there parameters. */
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# define STACK_VARIABLES_PARMS void *stackaddr, size_t stacksize
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/* How to declare allocate_stack. */
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# define ALLOCATE_STACK_PARMS void **stack, size_t *stacksize
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/* This is how the function is called. We do it this way to allow
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other variants of the function to have more parameters. */
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# define ALLOCATE_STACK(attr, pd) \
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allocate_stack (attr, pd, &stackaddr, &stacksize)
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#endif
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/* Default alignment of stack. */
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#ifndef STACK_ALIGN
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# define STACK_ALIGN __alignof__ (long double)
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#endif
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/* Default value for minimal stack size after allocating thread
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descriptor and guard. */
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#ifndef MINIMAL_REST_STACK
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# define MINIMAL_REST_STACK 4096
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#endif
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/* Let the architecture add some flags to the mmap() call used to
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allocate stacks. */
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#ifndef ARCH_MAP_FLAGS
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# define ARCH_MAP_FLAGS 0
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#endif
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/* This yields the pointer that TLS support code calls the thread pointer. */
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#if TLS_TCB_AT_TP
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# define TLS_TPADJ(pd) (pd)
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#elif TLS_DTV_AT_TP
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# define TLS_TPADJ(pd) ((struct pthread *)((char *) (pd) + TLS_PRE_TCB_SIZE))
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#endif
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/* Cache handling for not-yet free stacks. */
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/* Maximum size in kB of cache. */
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static size_t stack_cache_maxsize = 40 * 1024 * 1024; /* 40MiBi by default. */
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static size_t stack_cache_actsize;
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/* Mutex protecting this variable. */
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static lll_lock_t stack_cache_lock = LLL_LOCK_INITIALIZER;
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/* List of queued stack frames. */
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static LIST_HEAD (stack_cache);
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/* List of the stacks in use. */
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static LIST_HEAD (stack_used);
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/* List of the threads with user provided stacks in use. No need to
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initialize this, since it's done in __pthread_initialize_minimal. */
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list_t __stack_user __attribute__ ((nocommon));
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hidden_data_def (__stack_user)
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#if COLORING_INCREMENT != 0
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/* Number of threads created. */
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static unsigned int nptl_ncreated;
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#endif
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/* Check whether the stack is still used or not. */
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#define FREE_P(descr) ((descr)->tid <= 0)
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/* We create a double linked list of all cache entries. Double linked
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because this allows removing entries from the end. */
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/* Get a stack frame from the cache. We have to match by size since
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some blocks might be too small or far too large. */
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static struct pthread *
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get_cached_stack (size_t *sizep, void **memp)
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{
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size_t size = *sizep;
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struct pthread *result = NULL;
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list_t *entry;
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lll_lock (stack_cache_lock);
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/* Search the cache for a matching entry. We search for the
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smallest stack which has at least the required size. Note that
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in normal situations the size of all allocated stacks is the
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same. As the very least there are only a few different sizes.
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Therefore this loop will exit early most of the time with an
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exact match. */
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list_for_each (entry, &stack_cache)
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{
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struct pthread *curr;
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curr = list_entry (entry, struct pthread, list);
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if (FREE_P (curr) && curr->stackblock_size >= size)
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{
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if (curr->stackblock_size == size)
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{
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result = curr;
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break;
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}
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if (result == NULL
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|| result->stackblock_size > curr->stackblock_size)
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result = curr;
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}
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}
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if (__builtin_expect (result == NULL, 0)
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/* Make sure the size difference is not too excessive. In that
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case we do not use the block. */
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|| __builtin_expect (result->stackblock_size > 4 * size, 0))
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{
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/* Release the lock. */
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lll_unlock (stack_cache_lock);
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return NULL;
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}
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/* Dequeue the entry. */
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list_del (&result->list);
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/* And add to the list of stacks in use. */
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list_add (&result->list, &stack_used);
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/* And decrease the cache size. */
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stack_cache_actsize -= result->stackblock_size;
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/* Release the lock early. */
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lll_unlock (stack_cache_lock);
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/* Report size and location of the stack to the caller. */
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*sizep = result->stackblock_size;
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*memp = result->stackblock;
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/* Cancellation handling is back to the default. */
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result->cancelhandling = 0;
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result->cleanup = NULL;
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/* No pending event. */
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result->nextevent = NULL;
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/* Clear the DTV. */
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dtv_t *dtv = GET_DTV (TLS_TPADJ (result));
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memset (dtv, '\0', (dtv[-1].counter + 1) * sizeof (dtv_t));
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/* Re-initialize the TLS. */
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_dl_allocate_tls_init (TLS_TPADJ (result));
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return result;
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}
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/* Add a stack frame which is not used anymore to the stack. Must be
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called with the cache lock held. */
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static inline void
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__attribute ((always_inline))
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queue_stack (struct pthread *stack)
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{
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/* We unconditionally add the stack to the list. The memory may
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still be in use but it will not be reused until the kernel marks
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the stack as not used anymore. */
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list_add (&stack->list, &stack_cache);
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stack_cache_actsize += stack->stackblock_size;
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if (__builtin_expect (stack_cache_actsize > stack_cache_maxsize, 0))
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{
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/* We reduce the size of the cache. Remove the last entries
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until the size is below the limit. */
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list_t *entry;
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list_t *prev;
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/* Search from the end of the list. */
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list_for_each_prev_safe (entry, prev, &stack_cache)
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{
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struct pthread *curr;
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curr = list_entry (entry, struct pthread, list);
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if (FREE_P (curr))
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{
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/* Unlink the block. */
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list_del (entry);
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/* Account for the freed memory. */
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stack_cache_actsize -= curr->stackblock_size;
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/* Free the memory associated with the ELF TLS. */
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_dl_deallocate_tls (TLS_TPADJ (curr), false);
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/* Remove this block. This should never fail. If it
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does something is really wrong. */
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if (munmap (curr->stackblock, curr->stackblock_size) != 0)
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abort ();
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/* Maybe we have freed enough. */
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if (stack_cache_actsize <= stack_cache_maxsize)
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break;
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}
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}
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}
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}
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static int
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internal_function
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change_stack_perm (struct pthread *pd
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#ifdef NEED_SEPARATE_REGISTER_STACK
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, size_t pagemask
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#endif
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)
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{
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#ifdef NEED_SEPARATE_REGISTER_STACK
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void *stack = (pd->stackblock
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+ (((((pd->stackblock_size - pd->guardsize) / 2)
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& pagemask) + pd->guardsize) & pagemask));
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size_t len = pd->stackblock + pd->stackblock_size - stack;
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#else
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void *stack = pd->stackblock + pd->guardsize;
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size_t len = pd->stackblock_size - pd->guardsize;
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#endif
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if (mprotect (stack, len, PROT_READ | PROT_WRITE | PROT_EXEC) != 0)
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return errno;
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return 0;
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}
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static int
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allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
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ALLOCATE_STACK_PARMS)
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{
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struct pthread *pd;
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size_t size;
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size_t pagesize_m1 = __getpagesize () - 1;
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void *stacktop;
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assert (attr != NULL);
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assert (powerof2 (pagesize_m1 + 1));
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assert (TCB_ALIGNMENT >= STACK_ALIGN);
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/* Get the stack size from the attribute if it is set. Otherwise we
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use the default we determined at start time. */
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size = attr->stacksize ?: __default_stacksize;
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/* Get memory for the stack. */
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if (__builtin_expect (attr->flags & ATTR_FLAG_STACKADDR, 0))
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{
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uintptr_t adj;
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/* If the user also specified the size of the stack make sure it
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is large enough. */
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if (attr->stacksize != 0
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&& attr->stacksize < (__static_tls_size + MINIMAL_REST_STACK))
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return EINVAL;
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/* Adjust stack size for alignment of the TLS block. */
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#if TLS_TCB_AT_TP
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adj = ((uintptr_t) attr->stackaddr - TLS_TCB_SIZE)
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& __static_tls_align_m1;
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assert (size > adj + TLS_TCB_SIZE);
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#elif TLS_DTV_AT_TP
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adj = ((uintptr_t) attr->stackaddr - __static_tls_size)
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& __static_tls_align_m1;
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assert (size > adj);
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#endif
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/* The user provided some memory. Let's hope it matches the
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size... We do not allocate guard pages if the user provided
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the stack. It is the user's responsibility to do this if it
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is wanted. */
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#if TLS_TCB_AT_TP
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pd = (struct pthread *) ((uintptr_t) attr->stackaddr
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- TLS_TCB_SIZE - adj);
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#elif TLS_DTV_AT_TP
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pd = (struct pthread *) (((uintptr_t) attr->stackaddr
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- __static_tls_size - adj)
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- TLS_PRE_TCB_SIZE);
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#endif
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/* The user provided stack memory needs to be cleared. */
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memset (pd, '\0', sizeof (struct pthread));
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/* The first TSD block is included in the TCB. */
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pd->specific[0] = pd->specific_1stblock;
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/* Remember the stack-related values. */
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pd->stackblock = (char *) attr->stackaddr - size;
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pd->stackblock_size = size;
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/* This is a user-provided stack. It will not be queued in the
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stack cache nor will the memory (except the TLS memory) be freed. */
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pd->user_stack = true;
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/* This is at least the second thread. */
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pd->header.multiple_threads = 1;
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#ifndef TLS_MULTIPLE_THREADS_IN_TCB
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__pthread_multiple_threads = *__libc_multiple_threads_ptr = 1;
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#endif
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#ifdef NEED_DL_SYSINFO
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/* Copy the sysinfo value from the parent. */
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THREAD_SYSINFO(pd) = THREAD_SELF_SYSINFO;
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#endif
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/* The process ID is also the same as that of the caller. */
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pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
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/* Allocate the DTV for this thread. */
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if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL)
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/* Something went wrong. */
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return errno;
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/* Prepare to modify global data. */
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lll_lock (stack_cache_lock);
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/* And add to the list of stacks in use. */
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list_add (&pd->list, &__stack_user);
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lll_unlock (stack_cache_lock);
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}
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else
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{
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/* Allocate some anonymous memory. If possible use the cache. */
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size_t guardsize;
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size_t reqsize;
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void *mem;
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const int prot = (PROT_READ | PROT_WRITE
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| ((GL(dl_stack_flags) & PF_X) ? PROT_EXEC : 0));
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#if COLORING_INCREMENT != 0
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/* Add one more page for stack coloring. Don't do it for stacks
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with 16 times pagesize or larger. This might just cause
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unnecessary misalignment. */
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if (size <= 16 * pagesize_m1)
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size += pagesize_m1 + 1;
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#endif
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/* Adjust the stack size for alignment. */
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size &= ~__static_tls_align_m1;
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assert (size != 0);
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/* Make sure the size of the stack is enough for the guard and
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eventually the thread descriptor. */
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guardsize = (attr->guardsize + pagesize_m1) & ~pagesize_m1;
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if (__builtin_expect (size < (guardsize + __static_tls_size
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+ MINIMAL_REST_STACK + pagesize_m1 + 1),
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0))
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/* The stack is too small (or the guard too large). */
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return EINVAL;
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/* Try to get a stack from the cache. */
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reqsize = size;
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pd = get_cached_stack (&size, &mem);
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if (pd == NULL)
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{
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/* To avoid aliasing effects on a larger scale then pages we
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adjust the allocated stack size if necessary. This way
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allocations directly following each other will not have
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aliasing problems. */
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#if MULTI_PAGE_ALIASING != 0
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if ((size % MULTI_PAGE_ALIASING) == 0)
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size += pagesize_m1 + 1;
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#endif
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mem = mmap (NULL, size, prot,
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MAP_PRIVATE | MAP_ANONYMOUS | ARCH_MAP_FLAGS, -1, 0);
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if (__builtin_expect (mem == MAP_FAILED, 0))
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{
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#ifdef ARCH_RETRY_MMAP
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mem = ARCH_RETRY_MMAP (size);
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if (__builtin_expect (mem == MAP_FAILED, 0))
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#endif
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return errno;
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}
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/* SIZE is guaranteed to be greater than zero.
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So we can never get a null pointer back from mmap. */
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assert (mem != NULL);
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#if COLORING_INCREMENT != 0
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/* Atomically increment NCREATED. */
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unsigned int ncreated = atomic_increment_val (&nptl_ncreated);
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/* We chose the offset for coloring by incrementing it for
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every new thread by a fixed amount. The offset used
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module the page size. Even if coloring would be better
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relative to higher alignment values it makes no sense to
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do it since the mmap() interface does not allow us to
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specify any alignment for the returned memory block. */
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size_t coloring = (ncreated * COLORING_INCREMENT) & pagesize_m1;
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/* Make sure the coloring offsets does not disturb the alignment
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of the TCB and static TLS block. */
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if (__builtin_expect ((coloring & __static_tls_align_m1) != 0, 0))
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coloring = (((coloring + __static_tls_align_m1)
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& ~(__static_tls_align_m1))
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& ~pagesize_m1);
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#else
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/* Unless specified we do not make any adjustments. */
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# define coloring 0
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#endif
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/* Place the thread descriptor at the end of the stack. */
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#if TLS_TCB_AT_TP
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pd = (struct pthread *) ((char *) mem + size - coloring) - 1;
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#elif TLS_DTV_AT_TP
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pd = (struct pthread *) ((((uintptr_t) mem + size - coloring
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- __static_tls_size)
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& ~__static_tls_align_m1)
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- TLS_PRE_TCB_SIZE);
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#endif
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/* Remember the stack-related values. */
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pd->stackblock = mem;
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pd->stackblock_size = size;
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/* We allocated the first block thread-specific data array.
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This address will not change for the lifetime of this
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descriptor. */
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pd->specific[0] = pd->specific_1stblock;
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/* This is at least the second thread. */
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pd->header.multiple_threads = 1;
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#ifndef TLS_MULTIPLE_THREADS_IN_TCB
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__pthread_multiple_threads = *__libc_multiple_threads_ptr = 1;
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#endif
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#ifdef NEED_DL_SYSINFO
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/* Copy the sysinfo value from the parent. */
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THREAD_SYSINFO(pd) = THREAD_SELF_SYSINFO;
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#endif
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/* The process ID is also the same as that of the caller. */
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pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
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/* Allocate the DTV for this thread. */
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if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL)
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{
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/* Something went wrong. */
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int err = errno;
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/* Free the stack memory we just allocated. */
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(void) munmap (mem, size);
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return err;
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}
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/* Prepare to modify global data. */
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lll_lock (stack_cache_lock);
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/* And add to the list of stacks in use. */
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list_add (&pd->list, &stack_used);
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lll_unlock (stack_cache_lock);
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/* There might have been a race. Another thread might have
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|
caused the stacks to get exec permission while this new
|
|
stack was prepared. Detect if this was possible and
|
|
change the permission if necessary. */
|
|
if (__builtin_expect ((GL(dl_stack_flags) & PF_X) != 0
|
|
&& (prot & PROT_EXEC) == 0, 0))
|
|
{
|
|
int err = change_stack_perm (pd
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
, ~pagesize_m1
|
|
#endif
|
|
);
|
|
if (err != 0)
|
|
{
|
|
/* Free the stack memory we just allocated. */
|
|
(void) munmap (mem, size);
|
|
|
|
return err;
|
|
}
|
|
}
|
|
|
|
|
|
/* Note that all of the stack and the thread descriptor is
|
|
zeroed. This means we do not have to initialize fields
|
|
with initial value zero. This is specifically true for
|
|
the 'tid' field which is always set back to zero once the
|
|
stack is not used anymore and for the 'guardsize' field
|
|
which will be read next. */
|
|
}
|
|
|
|
/* Create or resize the guard area if necessary. */
|
|
if (__builtin_expect (guardsize > pd->guardsize, 0))
|
|
{
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
char *guard = mem + (((size - guardsize) / 2) & ~pagesize_m1);
|
|
#else
|
|
char *guard = mem;
|
|
#endif
|
|
if (mprotect (guard, guardsize, PROT_NONE) != 0)
|
|
{
|
|
int err;
|
|
mprot_error:
|
|
err = errno;
|
|
|
|
lll_lock (stack_cache_lock);
|
|
|
|
/* Remove the thread from the list. */
|
|
list_del (&pd->list);
|
|
|
|
lll_unlock (stack_cache_lock);
|
|
|
|
/* Get rid of the TLS block we allocated. */
|
|
_dl_deallocate_tls (TLS_TPADJ (pd), false);
|
|
|
|
/* Free the stack memory regardless of whether the size
|
|
of the cache is over the limit or not. If this piece
|
|
of memory caused problems we better do not use it
|
|
anymore. Uh, and we ignore possible errors. There
|
|
is nothing we could do. */
|
|
(void) munmap (mem, size);
|
|
|
|
return err;
|
|
}
|
|
|
|
pd->guardsize = guardsize;
|
|
}
|
|
else if (__builtin_expect (pd->guardsize - guardsize > size - reqsize,
|
|
0))
|
|
{
|
|
/* The old guard area is too large. */
|
|
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
char *guard = mem + (((size - guardsize) / 2) & ~pagesize_m1);
|
|
char *oldguard = mem + (((size - pd->guardsize) / 2) & ~pagesize_m1);
|
|
|
|
if (oldguard < guard
|
|
&& mprotect (oldguard, guard - oldguard, prot) != 0)
|
|
goto mprot_error;
|
|
|
|
if (mprotect (guard + guardsize,
|
|
oldguard + pd->guardsize - guard - guardsize,
|
|
prot) != 0)
|
|
goto mprot_error;
|
|
#else
|
|
if (mprotect ((char *) mem + guardsize, pd->guardsize - guardsize,
|
|
prot) != 0)
|
|
goto mprot_error;
|
|
#endif
|
|
|
|
pd->guardsize = guardsize;
|
|
}
|
|
/* The pthread_getattr_np() calls need to get passed the size
|
|
requested in the attribute, regardless of how large the
|
|
actually used guardsize is. */
|
|
pd->reported_guardsize = guardsize;
|
|
}
|
|
|
|
/* Initialize the lock. We have to do this unconditionally since the
|
|
stillborn thread could be canceled while the lock is taken. */
|
|
pd->lock = LLL_LOCK_INITIALIZER;
|
|
|
|
/* We place the thread descriptor at the end of the stack. */
|
|
*pdp = pd;
|
|
|
|
#if TLS_TCB_AT_TP
|
|
/* The stack begins before the TCB and the static TLS block. */
|
|
stacktop = ((char *) (pd + 1) - __static_tls_size);
|
|
#elif TLS_DTV_AT_TP
|
|
stacktop = (char *) (pd - 1);
|
|
#endif
|
|
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
*stack = pd->stackblock;
|
|
*stacksize = stacktop - *stack;
|
|
#else
|
|
*stack = stacktop;
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void
|
|
internal_function
|
|
__deallocate_stack (struct pthread *pd)
|
|
{
|
|
lll_lock (stack_cache_lock);
|
|
|
|
/* Remove the thread from the list of threads with user defined
|
|
stacks. */
|
|
list_del (&pd->list);
|
|
|
|
/* Not much to do. Just free the mmap()ed memory. Note that we do
|
|
not reset the 'used' flag in the 'tid' field. This is done by
|
|
the kernel. If no thread has been created yet this field is
|
|
still zero. */
|
|
if (__builtin_expect (! pd->user_stack, 1))
|
|
(void) queue_stack (pd);
|
|
else
|
|
/* Free the memory associated with the ELF TLS. */
|
|
_dl_deallocate_tls (TLS_TPADJ (pd), false);
|
|
|
|
lll_unlock (stack_cache_lock);
|
|
}
|
|
|
|
|
|
int
|
|
internal_function
|
|
__make_stacks_executable (void **stack_endp)
|
|
{
|
|
/* First the main thread's stack. */
|
|
int err = _dl_make_stack_executable (stack_endp);
|
|
if (err != 0)
|
|
return err;
|
|
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
const size_t pagemask = ~(__getpagesize () - 1);
|
|
#endif
|
|
|
|
lll_lock (stack_cache_lock);
|
|
|
|
list_t *runp;
|
|
list_for_each (runp, &stack_used)
|
|
{
|
|
err = change_stack_perm (list_entry (runp, struct pthread, list)
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
, pagemask
|
|
#endif
|
|
);
|
|
if (err != 0)
|
|
break;
|
|
}
|
|
|
|
/* Also change the permission for the currently unused stacks. This
|
|
might be wasted time but better spend it here than adding a check
|
|
in the fast path. */
|
|
if (err == 0)
|
|
list_for_each (runp, &stack_cache)
|
|
{
|
|
err = change_stack_perm (list_entry (runp, struct pthread, list)
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
, pagemask
|
|
#endif
|
|
);
|
|
if (err != 0)
|
|
break;
|
|
}
|
|
|
|
lll_unlock (stack_cache_lock);
|
|
|
|
return err;
|
|
}
|
|
|
|
|
|
/* In case of a fork() call the memory allocation in the child will be
|
|
the same but only one thread is running. All stacks except that of
|
|
the one running thread are not used anymore. We have to recycle
|
|
them. */
|
|
void
|
|
__reclaim_stacks (void)
|
|
{
|
|
struct pthread *self = (struct pthread *) THREAD_SELF;
|
|
|
|
/* No locking necessary. The caller is the only stack in use. */
|
|
|
|
/* Mark all stacks except the still running one as free. */
|
|
list_t *runp;
|
|
list_for_each (runp, &stack_used)
|
|
{
|
|
struct pthread *curp;
|
|
|
|
curp = list_entry (runp, struct pthread, list);
|
|
if (curp != self)
|
|
{
|
|
/* This marks the stack as free. */
|
|
curp->tid = 0;
|
|
|
|
/* The PID field must be initialized for the new process. */
|
|
curp->pid = self->pid;
|
|
|
|
/* Account for the size of the stack. */
|
|
stack_cache_actsize += curp->stackblock_size;
|
|
}
|
|
}
|
|
|
|
/* Add the stack of all running threads to the cache. */
|
|
list_splice (&stack_used, &stack_cache);
|
|
|
|
/* Remove the entry for the current thread to from the cache list
|
|
and add it to the list of running threads. Which of the two
|
|
lists is decided by the user_stack flag. */
|
|
list_del (&self->list);
|
|
|
|
/* Re-initialize the lists for all the threads. */
|
|
INIT_LIST_HEAD (&stack_used);
|
|
INIT_LIST_HEAD (&__stack_user);
|
|
|
|
if (__builtin_expect (THREAD_GETMEM (self, user_stack), 0))
|
|
list_add (&self->list, &__stack_user);
|
|
else
|
|
list_add (&self->list, &stack_used);
|
|
|
|
/* There is one thread running. */
|
|
__nptl_nthreads = 1;
|
|
|
|
/* Initialize the lock. */
|
|
stack_cache_lock = LLL_LOCK_INITIALIZER;
|
|
}
|
|
|
|
|
|
#if HP_TIMING_AVAIL
|
|
/* Find a thread given the thread ID. */
|
|
struct pthread *
|
|
attribute_hidden
|
|
__find_thread_by_id (pid_t tid)
|
|
{
|
|
struct pthread *result = NULL;
|
|
|
|
lll_lock (stack_cache_lock);
|
|
|
|
/* Iterate over the list with system-allocated threads first. */
|
|
list_t *runp;
|
|
list_for_each (runp, &stack_used)
|
|
{
|
|
struct pthread *curp;
|
|
|
|
curp = list_entry (runp, struct pthread, list);
|
|
|
|
if (curp->tid == tid)
|
|
{
|
|
result = curp;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* Now the list with threads using user-allocated stacks. */
|
|
list_for_each (runp, &__stack_user)
|
|
{
|
|
struct pthread *curp;
|
|
|
|
curp = list_entry (runp, struct pthread, list);
|
|
|
|
if (curp->tid == tid)
|
|
{
|
|
result = curp;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
out:
|
|
lll_unlock (stack_cache_lock);
|
|
|
|
return result;
|
|
}
|
|
#endif
|
|
|
|
static inline void __attribute__((always_inline))
|
|
init_one_static_tls (struct pthread *curp, struct link_map *map)
|
|
{
|
|
dtv_t *dtv = GET_DTV (TLS_TPADJ (curp));
|
|
# if TLS_TCB_AT_TP
|
|
void *dest = (char *) curp - map->l_tls_offset;
|
|
# elif TLS_DTV_AT_TP
|
|
void *dest = (char *) curp + map->l_tls_offset + TLS_PRE_TCB_SIZE;
|
|
# else
|
|
# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
|
|
# endif
|
|
|
|
/* Fill in the DTV slot so that a later LD/GD access will find it. */
|
|
dtv[map->l_tls_modid].pointer = dest;
|
|
|
|
/* Initialize the memory. */
|
|
memset (__mempcpy (dest, map->l_tls_initimage, map->l_tls_initimage_size),
|
|
'\0', map->l_tls_blocksize - map->l_tls_initimage_size);
|
|
}
|
|
|
|
void
|
|
attribute_hidden
|
|
__pthread_init_static_tls (struct link_map *map)
|
|
{
|
|
lll_lock (stack_cache_lock);
|
|
|
|
/* Iterate over the list with system-allocated threads first. */
|
|
list_t *runp;
|
|
list_for_each (runp, &stack_used)
|
|
init_one_static_tls (list_entry (runp, struct pthread, list), map);
|
|
|
|
/* Now the list with threads using user-allocated stacks. */
|
|
list_for_each (runp, &__stack_user)
|
|
init_one_static_tls (list_entry (runp, struct pthread, list), map);
|
|
|
|
lll_unlock (stack_cache_lock);
|
|
}
|