svn commit: r269909 - head/lib/libthr/thread
Konstantin Belousov
kib at FreeBSD.org
Wed Aug 13 05:53:42 UTC 2014
Author: kib
Date: Wed Aug 13 05:53:41 2014
New Revision: 269909
URL: http://svnweb.freebsd.org/changeset/base/269909
Log:
Add a knob LIBPTHREAD_BIGSTACK_MAIN, which instructs libthr to leave
the whole RLIMIT_STACK-sized region of the kernel-allocated stack as
the stack of main thread.
By default, the main thread stack is clamped at 2MB (4MB on 64bit
ABIs) and the rest is used for other threads stack allocation. Since
there is no programmatic way to adjust the size of the main thread
stack, pthread_attr_setstacksize() is too late, the knob allows user
to manage the main stack size both for single-threaded and
multi-threaded processes with the rlimit.
Reported by: "Ivan A. Kosarev" <ivan at ivan-labs.com>
Tested by: dim
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Modified:
head/lib/libthr/thread/thr_init.c
head/lib/libthr/thread/thr_stack.c
Modified: head/lib/libthr/thread/thr_init.c
==============================================================================
--- head/lib/libthr/thread/thr_init.c Wed Aug 13 05:47:49 2014 (r269908)
+++ head/lib/libthr/thread/thr_init.c Wed Aug 13 05:53:41 2014 (r269909)
@@ -37,6 +37,7 @@
#include <sys/types.h>
#include <sys/signalvar.h>
#include <sys/ioctl.h>
+#include <sys/resource.h>
#include <sys/sysctl.h>
#include <sys/ttycom.h>
#include <sys/mman.h>
@@ -441,6 +442,7 @@ init_main_thread(struct pthread *thread)
static void
init_private(void)
{
+ struct rlimit rlim;
size_t len;
int mib[2];
char *env;
@@ -471,6 +473,12 @@ init_private(void)
len = sizeof (_usrstack);
if (sysctl(mib, 2, &_usrstack, &len, NULL, 0) == -1)
PANIC("Cannot get kern.usrstack from sysctl");
+ env = getenv("LIBPTHREAD_BIGSTACK_MAIN");
+ if (env != NULL) {
+ if (getrlimit(RLIMIT_STACK, &rlim) == -1)
+ PANIC("Cannot get stack rlimit");
+ _thr_stack_initial = rlim.rlim_cur;
+ }
len = sizeof(_thr_is_smp);
sysctlbyname("kern.smp.cpus", &_thr_is_smp, &len, NULL, 0);
_thr_is_smp = (_thr_is_smp > 1);
Modified: head/lib/libthr/thread/thr_stack.c
==============================================================================
--- head/lib/libthr/thread/thr_stack.c Wed Aug 13 05:47:49 2014 (r269908)
+++ head/lib/libthr/thread/thr_stack.c Wed Aug 13 05:53:41 2014 (r269909)
@@ -246,7 +246,10 @@ _thr_stack_alloc(struct pthread_attr *at
THREAD_LIST_UNLOCK(curthread);
}
else {
- /* Allocate a stack from usrstack. */
+ /*
+ * Allocate a stack from or below usrstack, depending
+ * on the LIBPTHREAD_BIGSTACK_MAIN env variable.
+ */
if (last_stack == NULL)
last_stack = _usrstack - _thr_stack_initial -
_thr_guard_default;
More information about the svn-src-head
mailing list