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| author | Paul Pluzhnikov <ppluzhnikov@google.com> | 2013-12-18 16:24:19 -0800 |
|---|---|---|
| committer | Paul Pluzhnikov <ppluzhnikov@google.com> | 2013-12-18 16:24:19 -0800 |
| commit | 35e8f7ab94c910659de9d507aa0f3e1f8973d914 (patch) | |
| tree | fca3c69ec2085dbeee15673472350c9067ddf4f7 | |
| parent | 69a17d9d245dc3551792e95e1823cc2d877592f3 (diff) | |
| download | glibc-35e8f7ab94c910659de9d507aa0f3e1f8973d914.zip glibc-35e8f7ab94c910659de9d507aa0f3e1f8973d914.tar.gz glibc-35e8f7ab94c910659de9d507aa0f3e1f8973d914.tar.bz2 | |
Patch 3/4 of the effort to make TLS access async-signal-safe.
Factor out _dl_clear_dtv.
2013-12-18 Andrew Hunter <ahh@google.com>
* elf/Versions (ld): Add _dl_clear_dtv.
* sysdeps/generic/ldsodefs.h (_dl_clear_dtv): New prototype.
* elf/dl-tls.c (_dl_clear_dtv): New function.
* nptl/allocatestack.c (get_cached_stack): Call _dl_clear_dtv.
| -rw-r--r-- | ChangeLog | 7 | ||||
| -rw-r--r-- | elf/Versions | 1 | ||||
| -rw-r--r-- | elf/dl-tls.c | 12 | ||||
| -rw-r--r-- | nptl/allocatestack.c | 6 | ||||
| -rw-r--r-- | sysdeps/generic/ldsodefs.h | 5 |
5 files changed, 26 insertions, 5 deletions
@@ -1,5 +1,12 @@ 2013-12-18 Andrew Hunter <ahh@google.com> + * elf/Versions (ld): Add _dl_clear_dtv. + * sysdeps/generic/ldsodefs.h (_dl_clear_dtv): New prototype. + * elf/dl-tls.c (_dl_clear_dtv): New function. + * nptl/allocatestack.c (get_cached_stack): Call _dl_clear_dtv. + +2013-12-18 Andrew Hunter <ahh@google.com> + * sysdeps/generic/ldsodefs.h (_dl_mask_all_signals): New prototype. (_dl_unmask_signals): Likewise. * sysdeps/mach/hurd/dl-sysdep.h (_dl_mask_all_signals): New stub. diff --git a/elf/Versions b/elf/Versions index 2383992..01b7a59 100644 --- a/elf/Versions +++ b/elf/Versions @@ -53,6 +53,7 @@ ld { _dl_allocate_tls; _dl_allocate_tls_init; _dl_argv; _dl_find_dso_for_object; _dl_get_tls_static_info; _dl_deallocate_tls; _dl_make_stack_executable; _dl_out_of_memory; + _dl_clear_dtv; _dl_rtld_di_serinfo; _dl_starting_up; _dl_tls_setup; _rtld_global; _rtld_global_ro; diff --git a/elf/dl-tls.c b/elf/dl-tls.c index 576d9a1..c60a6b7 100644 --- a/elf/dl-tls.c +++ b/elf/dl-tls.c @@ -463,6 +463,18 @@ _dl_allocate_tls (void *mem) } rtld_hidden_def (_dl_allocate_tls) +void +internal_function +_dl_clear_dtv (dtv_t *dtv) +{ + for (size_t cnt = 0; cnt < dtv[-1].counter; ++cnt) + if (! dtv[1 + cnt].pointer.is_static + && dtv[1 + cnt].pointer.val != TLS_DTV_UNALLOCATED) + free (dtv[1 + cnt].pointer.val); + memset (dtv, '\0', (dtv[-1].counter + 1) * sizeof (dtv_t)); +} + +rtld_hidden_def (_dl_clear_dtv) #ifndef SHARED extern dtv_t _dl_static_dtv[]; diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c index 1e0fe1f..96e3845 100644 --- a/nptl/allocatestack.c +++ b/nptl/allocatestack.c @@ -242,11 +242,7 @@ get_cached_stack (size_t *sizep, void **memp) /* Clear the DTV. */ dtv_t *dtv = GET_DTV (TLS_TPADJ (result)); - for (size_t cnt = 0; cnt < dtv[-1].counter; ++cnt) - if (! dtv[1 + cnt].pointer.is_static - && dtv[1 + cnt].pointer.val != TLS_DTV_UNALLOCATED) - free (dtv[1 + cnt].pointer.val); - memset (dtv, '\0', (dtv[-1].counter + 1) * sizeof (dtv_t)); + _dl_clear_dtv (dtv); /* Re-initialize the TLS. */ _dl_allocate_tls_init (TLS_TPADJ (result)); diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index e919e41..1bda60c 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -989,6 +989,11 @@ extern void *_dl_allocate_tls_storage (void) extern void *_dl_allocate_tls_init (void *) internal_function; rtld_hidden_proto (_dl_allocate_tls_init) +/* Remove all allocated dynamic TLS regions from a DTV + for reuse by new thread. */ +extern void _dl_clear_dtv (dtv_t *dtv) internal_function; +rtld_hidden_proto (_dl_clear_dtv) + /* Deallocate memory allocated with _dl_allocate_tls. */ extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb) internal_function; rtld_hidden_proto (_dl_deallocate_tls) |