From 36ada9ee2cd3b686df6952446b92816584eacbb8 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Mon, 11 Nov 2019 09:20:09 +0100 Subject: support: Add support_set_small_thread_stack_size And support_small_stack_thread_attribute Change-Id: I1cf79a469984f8f30a4a947ee9ec2a5e74de8926 --- support/Makefile | 2 + support/support_set_small_thread_stack_size.c | 30 ++++++++++++++ support/support_small_stack_thread_attribute.c | 54 ++++++++++++++++++++++++++ support/xthread.h | 8 ++++ 4 files changed, 94 insertions(+) create mode 100644 support/support_set_small_thread_stack_size.c create mode 100644 support/support_small_stack_thread_attribute.c diff --git a/support/Makefile b/support/Makefile index ca238ee8b4..a6081bba98 100644 --- a/support/Makefile +++ b/support/Makefile @@ -63,7 +63,9 @@ libsupport-routines = \ support_quote_string \ support_record_failure \ support_run_diff \ + support_set_small_thread_stack_size \ support_shared_allocate \ + support_small_stack_thread_attribute \ support_subprocess \ support_test_compare_blob \ support_test_compare_failure \ diff --git a/support/support_set_small_thread_stack_size.c b/support/support_set_small_thread_stack_size.c new file mode 100644 index 0000000000..23189fd505 --- /dev/null +++ b/support/support_set_small_thread_stack_size.c @@ -0,0 +1,30 @@ +/* Set a small stack size, but still large enough for glibc's needs. + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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, see + . */ + +#include +#include +#include + +void +support_set_small_thread_stack_size (pthread_attr_t *attr) +{ + /* Some architectures have too small values for PTHREAD_STACK_MIN + which cannot be used for creating threads. Ensure that the stack + size is at least 256 KiB. */ + xpthread_attr_setstacksize (attr, MAX (256 * 1024, PTHREAD_STACK_MIN)); +} diff --git a/support/support_small_stack_thread_attribute.c b/support/support_small_stack_thread_attribute.c new file mode 100644 index 0000000000..a65097d8af --- /dev/null +++ b/support/support_small_stack_thread_attribute.c @@ -0,0 +1,54 @@ +/* A thread attribute with a small stack. + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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, see + . */ + +#include +#include + +static void * +allocate (void *closure) +{ + pthread_attr_t *result = malloc (sizeof (*result)); + xpthread_attr_init (result); + support_set_small_thread_stack_size (result); + return result; +} + +static void +deallocate (void *ptr, void *closure) +{ + xpthread_attr_destroy (ptr); + free (ptr); +} + +static void *small_stack_attr; + +pthread_attr_t * +support_small_stack_thread_attribute (void) +{ + return allocate_once (&small_stack_attr, allocate, deallocate, NULL); +} + +static void __attribute__ ((destructor)) +fini (void) +{ + if (small_stack_attr != NULL) + { + deallocate (small_stack_attr, NULL); + small_stack_attr = NULL; + } +} diff --git a/support/xthread.h b/support/xthread.h index 829397cbcc..f39720cb23 100644 --- a/support/xthread.h +++ b/support/xthread.h @@ -75,6 +75,14 @@ void xpthread_attr_setstacksize (pthread_attr_t *attr, void xpthread_attr_setguardsize (pthread_attr_t *attr, size_t guardsize); +/* Set the stack size in ATTR to a small value, but still large enough + to cover most internal glibc stack usage. */ +void support_set_small_thread_stack_size (pthread_attr_t *attr); + +/* Return a pointer to a thread attribute which requests a small + stack. The caller must not free this pointer. */ +pthread_attr_t *support_small_stack_thread_attribute (void); + /* This function returns non-zero if pthread_barrier_wait returned PTHREAD_BARRIER_SERIAL_THREAD. */ int xpthread_barrier_wait (pthread_barrier_t *barrier); -- cgit v1.2.1