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author | Rich Felker <dalias@aerifal.cx> | 2016-11-08 12:09:05 -0500 |
---|---|---|
committer | Rich Felker <dalias@aerifal.cx> | 2016-11-08 12:45:03 -0500 |
commit | 31fb174dd295e50f7c5cf18d31fcfd5fe5a063b7 (patch) | |
tree | d0cc757d2280d4711d40de2fa7ca3121593f11be /src | |
parent | ea7891a651dc4abc1305438470f1e4cc3b64ece2 (diff) | |
download | musl-31fb174dd295e50f7c5cf18d31fcfd5fe5a063b7.tar.gz musl-31fb174dd295e50f7c5cf18d31fcfd5fe5a063b7.tar.bz2 musl-31fb174dd295e50f7c5cf18d31fcfd5fe5a063b7.tar.xz musl-31fb174dd295e50f7c5cf18d31fcfd5fe5a063b7.zip |
add limited pthread_setattr_default_np API to set stack size defaults
based on patch by Timo Teräs:
While generally this is a bad API, it is the only existing API to
affect c++ (std::thread) and c11 (thrd_create) thread stack size.
This patch allows applications only to increate stack and guard
page sizes.
Diffstat (limited to 'src')
-rw-r--r-- | src/thread/pthread_create.c | 12 | ||||
-rw-r--r-- | src/thread/pthread_setattr_default_np.c | 35 |
2 files changed, 43 insertions, 4 deletions
diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c index e8d4a635..49f2f729 100644 --- a/src/thread/pthread_create.c +++ b/src/thread/pthread_create.c @@ -163,6 +163,8 @@ static void *dummy_tsd[1] = { 0 }; weak_alias(dummy_tsd, __pthread_tsd_main); volatile int __block_new_threads = 0; +size_t __default_stacksize = DEFAULT_STACK_SIZE; +size_t __default_guardsize = DEFAULT_GUARD_SIZE; static FILE *volatile dummy_file = 0; weak_alias(dummy_file, __stdin_used); @@ -186,10 +188,7 @@ int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict att | CLONE_THREAD | CLONE_SYSVSEM | CLONE_SETTLS | CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID | CLONE_DETACHED; int do_sched = 0; - pthread_attr_t attr = { - ._a_stacksize = DEFAULT_STACK_SIZE, - ._a_guardsize = DEFAULT_GUARD_SIZE, - }; + pthread_attr_t attr = { 0 }; if (!libc.can_do_threads) return ENOSYS; self = __pthread_self(); @@ -207,6 +206,11 @@ int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict att if (attrp && !c11) attr = *attrp; __acquire_ptc(); + if (!attrp || c11) { + attr._a_stacksize = __default_stacksize; + attr._a_guardsize = __default_guardsize; + } + if (__block_new_threads) __wait(&__block_new_threads, 0, 1, 1); if (attr._a_stackaddr) { diff --git a/src/thread/pthread_setattr_default_np.c b/src/thread/pthread_setattr_default_np.c new file mode 100644 index 00000000..ffd2712b --- /dev/null +++ b/src/thread/pthread_setattr_default_np.c @@ -0,0 +1,35 @@ +#include "pthread_impl.h" +#include <string.h> + +extern size_t __default_stacksize; +extern size_t __default_guardsize; + +int pthread_setattr_default_np(const pthread_attr_t *attrp) +{ + /* Reject anything in the attr object other than stack/guard size. */ + pthread_attr_t tmp = *attrp, zero = { 0 }; + tmp._a_stacksize = 0; + tmp._a_guardsize = 0; + if (memcmp(&tmp, &zero, sizeof tmp)) + return EINVAL; + + __inhibit_ptc(); + if (attrp->_a_stacksize >= __default_stacksize) + __default_stacksize = attrp->_a_stacksize; + if (attrp->_a_guardsize >= __default_guardsize) + __default_guardsize = attrp->_a_guardsize; + __release_ptc(); + + return 0; +} + +int pthread_getattr_default_np(pthread_attr_t *attrp) +{ + __acquire_ptc(); + *attrp = (pthread_attr_t) { + ._a_stacksize = __default_stacksize, + ._a_guardsize = __default_guardsize, + }; + __release_ptc(); + return 0; +} |