[haiku-commits] r34342 - haiku/trunk/src/system/libroot/posix/stdlib

From: ingo_weinhold@xxxxxx
To: haiku-commits@xxxxxxxxxxxxx
Date: Sun, 29 Nov 2009 12:17:53 +0100 (CET)
Author: bonefish
Date: 2009-11-29 12:17:53 +0100 (Sun, 29 Nov 2009)
New Revision: 34342
Changeset: http://dev.haiku-os.org/changeset/34342/haiku

Modified:
   haiku/trunk/src/system/libroot/posix/stdlib/exit.c
Log:
Replaced the hown-grown recursive lock implementation by a shared lazy
recursive lock. I haven't investigated it closer, but the previous
implementation was even broken -- "strace /bin/true" showed two
release_sem() calls, but no acquire_sem().


Modified: haiku/trunk/src/system/libroot/posix/stdlib/exit.c
===================================================================
--- haiku/trunk/src/system/libroot/posix/stdlib/exit.c  2009-11-29 11:14:50 UTC 
(rev 34341)
+++ haiku/trunk/src/system/libroot/posix/stdlib/exit.c  2009-11-29 11:17:53 UTC 
(rev 34342)
@@ -16,6 +16,7 @@
 #include <signal.h>
 
 #include <libroot_private.h>
+#include <locks.h>
 #include <runtime_loader.h>
 #include <syscalls.h>
 
@@ -24,44 +25,26 @@
 extern void _thread_do_exit_notification(void);
 
 struct exit_stack_info {
-       void            (*exit_stack[ATEXIT_MAX])(void);
-       int32           stack_size;
-       sem_id          lock;
-       vint32          lock_count;
-       thread_id       lock_owner;
-       size_t          recursion_count;
+       void                            (*exit_stack[ATEXIT_MAX])(void);
+       int32                           stack_size;
+       lazy_recursive_lock     lock;
 };
 
 
-static struct exit_stack_info sExitStackInfo = { {}, 0, -1, 0, -1, 0 };
+static struct exit_stack_info sExitStackInfo = { {}, 0, {} };
 
 
-static void
+static void inline
 _exit_stack_lock()
 {
-       thread_id self = find_thread(NULL);
-       if (self != sExitStackInfo.lock_owner) {
-               if (atomic_add(&sExitStackInfo.lock_count, 1) > 0) {
-                       while (acquire_sem(sExitStackInfo.lock) != B_OK)
-                               ;
-               }
-               sExitStackInfo.lock_owner = self;
-       }
-       sExitStackInfo.recursion_count++;
+       lazy_recursive_lock_lock(&sExitStackInfo.lock);
 }
 
 
-static void
+static void inline
 _exit_stack_unlock()
 {
-       if (sExitStackInfo.lock_owner != find_thread(NULL))
-               debugger("exit stack lock not owned");
-
-       if (sExitStackInfo.recursion_count-- == 1) {
-               sExitStackInfo.lock_owner = -1;
-               if (atomic_add(&sExitStackInfo.lock_count, -1) == 1)
-                       release_sem(sExitStackInfo.lock);
-       }
+       lazy_recursive_lock_unlock(&sExitStackInfo.lock);
 }
 
 
@@ -103,8 +86,9 @@
 void
 __init_exit_stack_lock(void)
 {
-       sExitStackInfo.lock = create_sem(0, "exit stack lock");
-       if (sExitStackInfo.lock < 0)
+       status_t error = lazy_recursive_lock_init(&sExitStackInfo.lock,
+               "exit stack lock");
+       if (error != B_OK)
                debugger("failed to create exit stack lock");
 }
[haiku-commits] r34342 - haiku/trunk/src/system/libroot/posix/stdlib

Other related posts:
