From: Mark Wielaard <mark@klomp.org>
To: elfutils-devel@sourceware.org
Cc: hsm2@rice.edu, Mark Wielaard <mark@klomp.org>
Subject: [PATCH 02/16] libelf: Make elf_version thread-safe
Date: Tue, 10 Oct 2023 15:42:46 +0200 [thread overview]
Message-ID: <20231010134300.53830-2-mark@klomp.org> (raw)
In-Reply-To: <20231010134300.53830-1-mark@klomp.org>
From: Heather McIntyre <hsm2@rice.edu>
* elf_version.c (version_once): Define once.
(initialize_version): New static function.
(elf_version): Use initialize_version version_once.
Signed-off-by: Heather S. McIntyre <hsm2@rice.edu>
Signed-off-by: Mark Wielaard <mark@klomp.org>
---
libelf/elf_version.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/libelf/elf_version.c b/libelf/elf_version.c
index 6ec534ab..8296bb65 100644
--- a/libelf/elf_version.c
+++ b/libelf/elf_version.c
@@ -32,12 +32,21 @@
#endif
#include <libelfP.h>
+#include <pthread.h>
+/* Multiple threads may initialize __libelf_version.
+ pthread_once() ensures that __libelf_version is initialized only once. */
+once_define(static, version_once);
/* Currently selected version. Should be EV_CURRENT.
Will be EV_NONE if elf_version () has not been called yet. */
unsigned int __libelf_version = EV_NONE;
+static void initialize_version(void)
+{
+ __libelf_version = EV_CURRENT;
+}
+
unsigned int
elf_version (unsigned int version)
{
@@ -49,7 +58,7 @@ elf_version (unsigned int version)
/* Phew, we know this version. */
/* Signal that the version is now initialized. */
- __libelf_version = EV_CURRENT;
+ once(version_once, initialize_version);
/* And return the last (or initial) version. */
return EV_CURRENT;
--
2.41.0
next prev parent reply other threads:[~2023-10-10 13:43 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-08 17:07 [PATCH] Fix thread-safety for elfutils Heather McIntyre
2023-08-21 22:08 ` John Mellor-Crummey
2023-08-25 14:10 ` Mark Wielaard
2023-10-10 13:40 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 01/16] lib: Add new once_define and once macros to eu-config.h Mark Wielaard
2023-10-10 13:42 ` Mark Wielaard [this message]
2023-10-10 14:00 ` [PATCH 02/16] libelf: Make elf_version thread-safe Mark Wielaard
2023-10-17 19:05 ` Heather McIntyre
2023-10-19 21:00 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 03/16] libelf: Fix deadlock in __libelf_readall Mark Wielaard
2023-10-10 15:06 ` Mark Wielaard
2023-10-17 19:11 ` Heather McIntyre
2023-11-09 13:26 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 04/16] libelf: Fix deadlock in elf_cntl Mark Wielaard
2023-10-10 15:23 ` Mark Wielaard
2023-10-17 19:14 ` Heather McIntyre
2023-10-10 13:42 ` [PATCH 05/16] libelf: Fix elf_end deadlock Mark Wielaard
2023-10-10 15:28 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 06/16] libelf: Make elf32_getchdr and elf64_getchdr thread-safe Mark Wielaard
2023-10-10 16:28 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 07/16] lib: Add eu_tsearch and eu_tfind Mark Wielaard
2023-10-10 16:51 ` Mark Wielaard
2023-10-17 20:52 ` Heather McIntyre
2023-10-10 13:42 ` [PATCH 08/16] libcpu: Change calls for tsearch/tfind to eu_tsearch/eu_tfind Mark Wielaard
2023-10-10 21:10 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 09/16] src: Use eu-search in nm and findtextrel Mark Wielaard
2023-10-10 21:25 ` Mark Wielaard
2023-10-17 19:20 ` Heather McIntyre
2023-10-10 13:42 ` [PATCH 10/16] libdw: make dwarf_getalt thread-safe Mark Wielaard
2023-10-10 22:02 ` Mark Wielaard
2023-10-17 19:25 ` Heather McIntyre
2023-10-10 13:42 ` [PATCH 11/16] libdw: Add locking around __libdw_dieabbrev for dwarf_hasattr Mark Wielaard
2023-10-11 15:10 ` Mark Wielaard
2023-10-17 19:57 ` Heather McIntyre
2023-10-19 22:06 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 12/16] libdw: Make libdw_find_split_unit thread-safe Mark Wielaard
2023-10-11 17:17 ` Mark Wielaard
2023-10-17 20:01 ` Heather McIntyre
2023-10-10 13:42 ` [PATCH 13/16] libdw: Make libdw_findcu thread-safe Mark Wielaard
2023-10-12 22:02 ` Mark Wielaard
2023-10-17 20:10 ` Heather McIntyre
2023-10-10 13:42 ` [PATCH 14/16] libdw,libdwfl: Use eu-search for thread-safety Mark Wielaard
2023-10-12 22:05 ` Mark Wielaard
2023-10-10 13:42 ` [PATCH 15/16] tests: Add eu-search tests Mark Wielaard
2023-10-13 14:38 ` Mark Wielaard
2023-10-10 13:43 ` [PATCH 16/16] configure: No longer mark --enable-thread-safety as EXPERIMENTAL Mark Wielaard
2023-10-12 22:09 ` Mark Wielaard
2023-10-10 13:54 ` [PATCH 01/16] lib: Add new once_define and once macros to eu-config.h Mark Wielaard
2023-10-14 15:39 ` [PATCH] Fix thread-safety for elfutils Mark Wielaard
2023-10-14 18:29 ` Heather McIntyre
2023-10-17 15:04 ` Mark Wielaard
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