src/lib/libthr/thread/thr_stack.c, branch releng/11.3

Revert r330897:

2018-03-29T02:50:57Z

This was intended to be a non-functional change. It wasn't. The commit message was thus wrong. In addition it broke arm, and merged crypto related code. Revert with prejudice. This revert skips files touched in r316370 since that commit was since MFCed. This revert also skips files that require $FreeBSD$ property changes. Thank you to those who helped me get out of this mess including but not limited to gonzo, kevans, rgrimes. Requested by: gjb (re)

Partial merge of the SPDX changes

2018-03-14T03:19:51Z

These changes are incomplete but are making it difficult to determine what other changes can/should be merged. No objections from: pfg

Use __FBSDID() for .c files from lib/libthr/thread.

2016-04-08T11:15:26Z

If libthr.so is dlopened without RTLD_GLOBAL flag, the libthr symbols

2016-02-08T19:24:13Z

do not participate in the global symbols namespace, but rtld locks are still replaced and functions are interposed. In particular, __pthread_map_stacks_exec is resolved to the libc version. If a library is loaded later, which requires adjustment of the stack protection mode, rtld calls into libc __pthread_map_stacks_exec due to the symbols scope. The libc version might recurse into binder and recursively acquire rtld bind lock, causing the hang. Make libc __pthread_map_stacks_exec() interposed, which synchronizes rtld locks and version of the stack exec hook when libthr loaded, regardless of the symbol scope control or symbol resolution order. The __pthread_map_stacks_exec() symbol is removed from the private version in libthr since libc symbol now operates correctly in presence of libthr. Reported and tested by: markj Sponsored by: The FreeBSD Foundation MFC after: 2 weeks

Add a knob LIBPTHREAD_BIGSTACK_MAIN, which instructs libthr to leave

2014-08-13T05:53:41Z

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" Tested by: dim Sponsored by: The FreeBSD Foundation MFC after: 3 days

Style.

2014-08-13T05:47:49Z

Sponsored by: The FreeBSD Foundation MFC after: 3 days

For the process that already loaded libthr but still not initialized

2011-01-10T16:10:25Z

threading, fall back to libc method of performing __pthread_map_stacks_exec() job. Reported and tested by: Mykola Dzham

Implement the __pthread_map_stacks_exec() for libthr.

2011-01-09T12:38:40Z
Stack creation code is changed to call _rtld_get_stack_prot() to get the stack protection right. There is a race where thread is created during dlopen() of dso that requires executable stacks. Then, _rtld_get_stack_prot() may return PROT_READ | PROT_WRITE, but thread is still not linked into the thread list. In this case, the callback misses the thread stack, and rechecks the required protection afterward. Reviewed by: davidxu

Convert thread list lock from mutex to rwlock.

2010-09-13T07:03:01Z

WARNS level 4 cleanup.

2006-04-04T02:57:49Z