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-rw-r--r--lib/libkse/thread/thr_stack.c258
1 files changed, 0 insertions, 258 deletions
diff --git a/lib/libkse/thread/thr_stack.c b/lib/libkse/thread/thr_stack.c
deleted file mode 100644
index f634055..0000000
--- a/lib/libkse/thread/thr_stack.c
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@@ -1,258 +0,0 @@
-/*
- * Copyright (c) 2001 Daniel Eischen <deischen@freebsd.org>
- * Copyright (c) 2000-2001 Jason Evans <jasone@freebsd.org>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * $FreeBSD$
- */
-#include <sys/types.h>
-#include <sys/mman.h>
-#include <sys/queue.h>
-#include <stdlib.h>
-#include <pthread.h>
-#include "thr_private.h"
-
-/* Spare thread stack. */
-struct stack {
- LIST_ENTRY(stack) qe; /* Stack queue linkage. */
- size_t stacksize; /* Stack size (rounded up). */
- size_t guardsize; /* Guard size. */
- void *stackaddr; /* Stack address. */
-};
-
-/*
- * Default sized (stack and guard) spare stack queue. Stacks are cached
- * to avoid additional complexity managing mmap()ed stack regions. Spare
- * stacks are used in LIFO order to increase cache locality.
- */
-static LIST_HEAD(, stack) dstackq = LIST_HEAD_INITIALIZER(dstackq);
-
-/*
- * Miscellaneous sized (non-default stack and/or guard) spare stack queue.
- * Stacks are cached to avoid additional complexity managing mmap()ed
- * stack regions. This list is unordered, since ordering on both stack
- * size and guard size would be more trouble than it's worth. Stacks are
- * allocated from this cache on a first size match basis.
- */
-static LIST_HEAD(, stack) mstackq = LIST_HEAD_INITIALIZER(mstackq);
-
-/**
- * Base address of the last stack allocated (including its red zone, if
- * there is one). Stacks are allocated contiguously, starting beyond the
- * top of the main stack. When a new stack is created, a red zone is
- * typically created (actually, the red zone is mapped with PROT_NONE) above
- * the top of the stack, such that the stack will not be able to grow all
- * the way to the bottom of the next stack. This isn't fool-proof. It is
- * possible for a stack to grow by a large amount, such that it grows into
- * the next stack, and as long as the memory within the red zone is never
- * accessed, nothing will prevent one thread stack from trouncing all over
- * the next.
- *
- * low memory
- * . . . . . . . . . . . . . . . . . .
- * | |
- * | stack 3 | start of 3rd thread stack
- * +-----------------------------------+
- * | |
- * | Red Zone (guard page) | red zone for 2nd thread
- * | |
- * +-----------------------------------+
- * | stack 2 - PTHREAD_STACK_DEFAULT | top of 2nd thread stack
- * | |
- * | |
- * | |
- * | |
- * | stack 2 |
- * +-----------------------------------+ <-- start of 2nd thread stack
- * | |
- * | Red Zone | red zone for 1st thread
- * | |
- * +-----------------------------------+
- * | stack 1 - PTHREAD_STACK_DEFAULT | top of 1st thread stack
- * | |
- * | |
- * | |
- * | |
- * | stack 1 |
- * +-----------------------------------+ <-- start of 1st thread stack
- * | | (initial value of last_stack)
- * | Red Zone |
- * | | red zone for main thread
- * +-----------------------------------+
- * | USRSTACK - PTHREAD_STACK_INITIAL | top of main thread stack
- * | | ^
- * | | |
- * | | |
- * | | | stack growth
- * | |
- * +-----------------------------------+ <-- start of main thread stack
- * (USRSTACK)
- * high memory
- *
- */
-static void *last_stack = NULL;
-
-/*
- * Round size up to the nearest multiple of
- * _thr_page_size.
- */
-static inline size_t
-round_up(size_t size)
-{
- if (size % _thr_page_size != 0)
- size = ((size / _thr_page_size) + 1) *
- _thr_page_size;
- return size;
-}
-
-int
-_thr_stack_alloc(struct pthread_attr *attr)
-{
- struct stack *spare_stack;
- struct kse *curkse;
- kse_critical_t crit;
- size_t stacksize;
- size_t guardsize;
- char *stackaddr;
-
- /*
- * Round up stack size to nearest multiple of _thr_page_size so
- * that mmap() * will work. If the stack size is not an even
- * multiple, we end up initializing things such that there is
- * unused space above the beginning of the stack, so the stack
- * sits snugly against its guard.
- */
- stacksize = round_up(attr->stacksize_attr);
- guardsize = round_up(attr->guardsize_attr);
-
- attr->stackaddr_attr = NULL;
- attr->flags &= ~THR_STACK_USER;
-
- /*
- * Use the garbage collector lock for synchronization of the
- * spare stack lists and allocations from usrstack.
- */
- crit = _kse_critical_enter();
- curkse = _get_curkse();
- KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
- /*
- * If the stack and guard sizes are default, try to allocate a stack
- * from the default-size stack cache:
- */
- if ((stacksize == _thr_stack_default) &&
- (guardsize == _thr_guard_default)) {
- if ((spare_stack = LIST_FIRST(&dstackq)) != NULL) {
- /* Use the spare stack. */
- LIST_REMOVE(spare_stack, qe);
- attr->stackaddr_attr = spare_stack->stackaddr;
- }
- }
- /*
- * The user specified a non-default stack and/or guard size, so try to
- * allocate a stack from the non-default size stack cache, using the
- * rounded up stack size (stack_size) in the search:
- */
- else {
- LIST_FOREACH(spare_stack, &mstackq, qe) {
- if (spare_stack->stacksize == stacksize &&
- spare_stack->guardsize == guardsize) {
- LIST_REMOVE(spare_stack, qe);
- attr->stackaddr_attr = spare_stack->stackaddr;
- break;
- }
- }
- }
- if (attr->stackaddr_attr != NULL) {
- /* A cached stack was found. Release the lock. */
- KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
- _kse_critical_leave(crit);
- }
- else {
- /* Allocate a stack from usrstack. */
- if (last_stack == NULL)
- last_stack = _usrstack - _thr_stack_initial -
- _thr_guard_default;
-
- /* Allocate a new stack. */
- stackaddr = last_stack - stacksize - guardsize;
-
- /*
- * Even if stack allocation fails, we don't want to try to
- * use this location again, so unconditionally decrement
- * last_stack. Under normal operating conditions, the most
- * likely reason for an mmap() error is a stack overflow of
- * the adjacent thread stack.
- */
- last_stack -= (stacksize + guardsize);
-
- /* Release the lock before mmap'ing it. */
- KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
- _kse_critical_leave(crit);
-
- /* Map the stack and guard page together, and split guard
- page from allocated space: */
- if ((stackaddr = mmap(stackaddr, stacksize+guardsize,
- PROT_READ | PROT_WRITE, MAP_STACK,
- -1, 0)) != MAP_FAILED &&
- (guardsize == 0 ||
- mprotect(stackaddr, guardsize, PROT_NONE) == 0)) {
- stackaddr += guardsize;
- } else {
- if (stackaddr != MAP_FAILED)
- munmap(stackaddr, stacksize + guardsize);
- stackaddr = NULL;
- }
- attr->stackaddr_attr = stackaddr;
- }
- if (attr->stackaddr_attr != NULL)
- return (0);
- else
- return (-1);
-}
-
-/* This function must be called with _thread_list_lock held. */
-void
-_thr_stack_free(struct pthread_attr *attr)
-{
- struct stack *spare_stack;
-
- if ((attr != NULL) && ((attr->flags & THR_STACK_USER) == 0)
- && (attr->stackaddr_attr != NULL)) {
- spare_stack = (attr->stackaddr_attr + attr->stacksize_attr
- - sizeof(struct stack));
- spare_stack->stacksize = round_up(attr->stacksize_attr);
- spare_stack->guardsize = round_up(attr->guardsize_attr);
- spare_stack->stackaddr = attr->stackaddr_attr;
-
- if (spare_stack->stacksize == _thr_stack_default &&
- spare_stack->guardsize == _thr_guard_default) {
- /* Default stack/guard size. */
- LIST_INSERT_HEAD(&dstackq, spare_stack, qe);
- } else {
- /* Non-default stack/guard size. */
- LIST_INSERT_HEAD(&mstackq, spare_stack, qe);
- }
- attr->stackaddr_attr = NULL;
- }
-}
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