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authorthorpej <thorpej@NetBSD.org>2003-01-18 10:32:11 +0000
committerthorpej <thorpej@NetBSD.org>2003-01-18 10:32:11 +0000
commitc62a74e6d5cfb2fb5034e98b983da7e2fc87709d (patch)
treef1281fd7111ddb57951e4472b342b53a2f56244a /lib/libpthread/pthread_stack.c
parentaf919042eceb8c19f42acd688efa8cf58168af5d (diff)
Merge the nathanw_sa branch.
Diffstat (limited to 'lib/libpthread/pthread_stack.c')
-rw-r--r--lib/libpthread/pthread_stack.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/lib/libpthread/pthread_stack.c b/lib/libpthread/pthread_stack.c
new file mode 100644
index 00000000000..d134b804101
--- /dev/null
+++ b/lib/libpthread/pthread_stack.c
@@ -0,0 +1,146 @@
+/* $NetBSD: pthread_stack.c,v 1.2 2003/01/18 10:34:16 thorpej Exp $ */
+
+/*-
+ * Copyright (c) 2001 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Nathan J. Williams.
+ *
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the NetBSD
+ * Foundation, Inc. and its contributors.
+ * 4. Neither the name of The NetBSD Foundation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
+ */
+
+#include <assert.h>
+#include <err.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <unistd.h>
+#include <sys/queue.h>
+#include <sys/mman.h>
+
+#include <sched.h>
+#include "pthread.h"
+#include "pthread_int.h"
+
+static pthread_t
+pthread__stackid_setup(void *base, int size);
+
+
+/* Allocate a stack for a thread, and set it up. It needs to be aligned, so
+ * that a thread can find itself by its stack pointer.
+ */
+int
+pthread__stackalloc(pthread_t *newt)
+{
+ void *addr;
+ int ret;
+ vaddr_t a, b, c, d;
+
+ /* The mmap() interface doesn't let us specify alignment,
+ * so we work around it by mmap()'ing twice the needed space,
+ * then unmapping the unaligned stuff on the edges.
+ */
+
+ addr = mmap(0, 2 * PT_STACKSIZE, PROT_READ|PROT_WRITE,
+ MAP_ANON|MAP_PRIVATE, -1, 0);
+ if (addr == MAP_FAILED)
+ return ENOMEM;
+
+ a = (vaddr_t) addr;
+
+ if ((a & PT_STACKMASK) != 0) {
+ b = (a & ~PT_STACKMASK) + PT_STACKSIZE;
+ ret = munmap((void *)a, b-a);
+ if (ret == -1)
+ return ENOMEM;
+ } else {
+ b = a;
+ }
+
+ c = b + PT_STACKSIZE;
+ d = a + 2*PT_STACKSIZE;
+
+ ret = munmap((void *)c, d-c);
+ if (ret == -1)
+ return ENOMEM;
+
+ *newt = pthread__stackid_setup((void *)b, PT_STACKSIZE);
+ return 0;
+}
+
+
+/*
+ * Set up the slightly special stack for the "initial" thread, which
+ * runs on the normal system stack, and thus gets slightly different
+ * treatment.
+ */
+void
+pthread__initmain(pthread_t *newt)
+{
+ void *base;
+
+ base = (void *) (pthread__sp() & ~PT_STACKMASK);
+
+ *newt = pthread__stackid_setup(base, PT_STACKSIZE);
+}
+
+static pthread_t
+pthread__stackid_setup(void *base, int size)
+{
+ pthread_t t;
+ int pagesize, ret;
+
+ /* Protect the next-to-bottom stack page as a red zone. */
+ /* XXX assumes that the stack grows down. */
+ pagesize = sysconf(_SC_PAGESIZE);
+ ret = mprotect( (char *)base + pagesize, pagesize, PROT_NONE);
+ if (ret == -1)
+ err(2, "Couldn't mprotect() stack redzone at %p\n",
+ (char *)base + pagesize);
+ /*
+ * Put a pointer to the pthread in the bottom (but
+ * redzone-protected section) of the stack.
+ */
+ t = base;
+
+ t->pt_stack.ss_sp = (char *)base + 2 * pagesize;
+ t->pt_stack.ss_size = PT_STACKSIZE - 2 * pagesize;
+
+ /* Set up an initial ucontext pointer to a "safe" area */
+ t->pt_uc =(ucontext_t *) ((char *)t->pt_stack.ss_sp +
+ t->pt_stack.ss_size - (pagesize/2));
+#ifdef _UC_UCONTEXT_ALIGN
+ t->pt_uc = (ucontext_t *)((uintptr_t)t->pt_uc & _UC_UCONTEXT_ALIGN);
+#endif
+
+ return t;
+}