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Diffstat (limited to 'sysdeps/nptl/fork.c')
-rw-r--r--sysdeps/nptl/fork.c96
1 files changed, 3 insertions, 93 deletions
diff --git a/sysdeps/nptl/fork.c b/sysdeps/nptl/fork.c
index 846fa49..f00dd64 100644
--- a/sysdeps/nptl/fork.c
+++ b/sysdeps/nptl/fork.c
@@ -48,11 +48,6 @@ pid_t
__libc_fork (void)
{
pid_t pid;
- struct used_handler
- {
- struct fork_handler *handler;
- struct used_handler *next;
- } *allp = NULL;
/* Determine if we are running multiple threads. We skip some fork
handlers in the single-thread case, to make fork safer to use in
@@ -60,60 +55,7 @@ __libc_fork (void)
but our current fork implementation is not. */
bool multiple_threads = THREAD_GETMEM (THREAD_SELF, header.multiple_threads);
- /* Run all the registered preparation handlers. In reverse order.
- While doing this we build up a list of all the entries. */
- struct fork_handler *runp;
- while ((runp = __fork_handlers) != NULL)
- {
- /* Make sure we read from the current RUNP pointer. */
- atomic_full_barrier ();
-
- unsigned int oldval = runp->refcntr;
-
- if (oldval == 0)
- /* This means some other thread removed the list just after
- the pointer has been loaded. Try again. Either the list
- is empty or we can retry it. */
- continue;
-
- /* Bump the reference counter. */
- if (atomic_compare_and_exchange_bool_acq (&__fork_handlers->refcntr,
- oldval + 1, oldval))
- /* The value changed, try again. */
- continue;
-
- /* We bumped the reference counter for the first entry in the
- list. That means that none of the following entries will
- just go away. The unloading code works in the order of the
- list.
-
- While executing the registered handlers we are building a
- list of all the entries so that we can go backward later on. */
- while (1)
- {
- /* Execute the handler if there is one. */
- if (runp->prepare_handler != NULL)
- runp->prepare_handler ();
-
- /* Create a new element for the list. */
- struct used_handler *newp
- = (struct used_handler *) alloca (sizeof (*newp));
- newp->handler = runp;
- newp->next = allp;
- allp = newp;
-
- /* Advance to the next handler. */
- runp = runp->next;
- if (runp == NULL)
- break;
-
- /* Bump the reference counter for the next entry. */
- atomic_increment (&runp->refcntr);
- }
-
- /* We are done. */
- break;
- }
+ __run_fork_handlers (atfork_run_prepare);
/* If we are not running multiple threads, we do not have to
preserve lock state. If fork runs from a signal handler, only
@@ -198,29 +140,7 @@ __libc_fork (void)
__rtld_lock_initialize (GL(dl_load_lock));
/* Run the handlers registered for the child. */
- while (allp != NULL)
- {
- if (allp->handler->child_handler != NULL)
- allp->handler->child_handler ();
-
- /* Note that we do not have to wake any possible waiter.
- This is the only thread in the new process. The count
- may have been bumped up by other threads doing a fork.
- We reset it to 1, to avoid waiting for non-existing
- thread(s) to release the count. */
- allp->handler->refcntr = 1;
-
- /* XXX We could at this point look through the object pool
- and mark all objects not on the __fork_handlers list as
- unused. This is necessary in case the fork() happened
- while another thread called dlclose() and that call had
- to create a new list. */
-
- allp = allp->next;
- }
-
- /* Initialize the fork lock. */
- __fork_lock = LLL_LOCK_INITIALIZER;
+ __run_fork_handlers (atfork_run_child);
}
else
{
@@ -235,17 +155,7 @@ __libc_fork (void)
}
/* Run the handlers registered for the parent. */
- while (allp != NULL)
- {
- if (allp->handler->parent_handler != NULL)
- allp->handler->parent_handler ();
-
- if (atomic_decrement_and_test (&allp->handler->refcntr)
- && allp->handler->need_signal)
- futex_wake (&allp->handler->refcntr, 1, FUTEX_PRIVATE);
-
- allp = allp->next;
- }
+ __run_fork_handlers (atfork_run_parent);
}
return pid;