mirror/glibc - mirror of git://sourceware.org/git/glibc.git

	Commit message (Collapse)	Author	Age	Files	Lines
*	Update copyright dates with scripts/update-copyrights.	Joseph Myers	2016-01-04	1	-1/+1
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*	Harden tls_dtor_list with pointer mangling [BZ #19018]	Florian Weimer	2015-10-06	1	-1/+9
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*	Mention dl_load_lock by name in the comments	Siddhesh Poyarekar	2015-07-24	1	-9/+10
\| \| \| \| \|	Mention dl_load_lock by name instead of just 'load lock' in the comments. This makes it unambigious which lock we're talking about.
*	Also use l_tls_dtor_count to decide on object unload (BZ #18657)	Siddhesh Poyarekar	2015-07-23	1	-18/+72
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	When an TLS destructor is registered, we set the DF_1_NODELETE flag to signal that the object should not be destroyed. We then clear the DF_1_NODELETE flag when all destructors are called, which is wrong - the flag could have been set by other means too. This patch replaces this use of the flag by using l_tls_dtor_count directly to determine whether it is safe to unload the object. This change has the added advantage of eliminating the lock taking when calling the destructors, which could result in a deadlock. The patch also fixes the test case tst-tls-atexit - it was making an invalid dlclose call, which would just return an error silently. I have also added a detailed note on concurrency which also aims to justify why I chose the semantics I chose for accesses to l_tls_dtor_count. Thanks to Torvald for his help in getting me started on this and (literally) teaching my how to approach the problem. Change verified on x86_64; the test suite does not show any regressions due to the patch. ChangeLog: [BZ #18657] * elf/dl-close.c (_dl_close_worker): Don't unload DSO if there are pending TLS destructor calls. * include/link.h (struct link_map): Add concurrency note for L_TLS_DTOR_COUNT. * stdlib/cxa_thread_atexit_impl.c (__cxa_thread_atexit_impl): Don't touch the link map flag. Atomically increment l_tls_dtor_count. (__call_tls_dtors): Atomically decrement l_tls_dtor_count. Avoid taking the load lock and don't touch the link map flag. * stdlib/tst-tls-atexit-nodelete.c: New test case. * stdlib/Makefile (tests): Use it. * stdlib/tst-tls-atexit.c (do_test): dlopen tst-tls-atexit-lib.so again before dlclose. Add conditionals to allow tst-tls-atexit-nodelete test case to use it.
*	Whitespace fixup in cxa_thread_atexit_impl.c	Siddhesh Poyarekar	2015-07-16	1	-1/+1
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*	Update copyright dates with scripts/update-copyrights.	Joseph Myers	2015-01-02	1	-1/+1
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*	Use glibc_likely instead __builtin_expect.	Ondřej Bílka	2014-02-10	1	-1/+1
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*	Update copyright notices with scripts/update-copyrights	Allan McRae	2014-01-01	1	-1/+1
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*	Avoid unconditional __call_tls_dtors calls in static linking.	Roland McGrath	2013-03-28	1	-1/+1
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*	Fix copyright year in new files	Siddhesh Poyarekar	2013-02-19	1	-1/+1
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*	C++11 thread_local destructors support	Siddhesh Poyarekar	2013-02-18	1	-0/+102
	This feature is specifically for the C++ compiler to offload calling thread_local object destructors on thread program exit, to glibc. This is to overcome the possible complication of destructors of thread_local objects getting called after the DSO in which they're defined is unloaded by the dynamic linker. The DSO is marked as 'unloadable' if it has a constructed thread_local object and marked as 'unloadable' again when all the constructed thread_local objects defined in it are destroyed.