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-rw-r--r--lib/libkse/thread/thr_sig.c86
1 files changed, 42 insertions, 44 deletions
diff --git a/lib/libkse/thread/thr_sig.c b/lib/libkse/thread/thr_sig.c
index d0d5f8b..3e55d65 100644
--- a/lib/libkse/thread/thr_sig.c
+++ b/lib/libkse/thread/thr_sig.c
@@ -39,9 +39,7 @@
#include "pthread_private.h"
/* Static variables: */
-static int volatile yield_on_unlock_dead = 0;
static int volatile yield_on_unlock_thread = 0;
-static spinlock_t thread_dead_lock = _SPINLOCK_INITIALIZER;
static spinlock_t thread_link_list_lock = _SPINLOCK_INITIALIZER;
/* Lock the thread list: */
@@ -52,14 +50,6 @@ _lock_thread_list()
_SPINLOCK(&thread_link_list_lock);
}
-/* Lock the dead thread list: */
-void
-_lock_dead_thread_list()
-{
- /* Lock the dead thread list: */
- _SPINLOCK(&thread_dead_lock);
-}
-
/* Lock the thread list: */
void
_unlock_thread_list()
@@ -80,26 +70,6 @@ _unlock_thread_list()
}
}
-/* Lock the dead thread list: */
-void
-_unlock_dead_thread_list()
-{
- /* Unlock the dead thread list: */
- _SPINUNLOCK(&thread_dead_lock);
-
- /*
- * Check if a scheduler interrupt occurred while the dead
- * thread list was locked:
- */
- if (yield_on_unlock_dead) {
- /* Reset the interrupt flag: */
- yield_on_unlock_dead = 0;
-
- /* This thread has overstayed it's welcome: */
- sched_yield();
- }
-}
-
void
_thread_sig_handler(int sig, int code, struct sigcontext * scp)
{
@@ -144,18 +114,6 @@ _thread_sig_handler(int sig, int code, struct sigcontext * scp)
*/
yield_on_unlock_thread = 1;
- /* Check if the scheduler interrupt has come at an
- * unfortunate time which one of the threads is
- * modifying the dead thread list:
- */
- if (thread_dead_lock.access_lock)
- /*
- * Set a flag so that the thread that has
- * the lock yields when it unlocks the
- * dead thread list:
- */
- yield_on_unlock_dead = 1;
-
/*
* Check if the kernel has not been interrupted while
* executing scheduler code:
@@ -198,7 +156,7 @@ _thread_sig_handler(int sig, int code, struct sigcontext * scp)
/*
* POSIX says that pending SIGCONT signals are
- * discarded when one of there signals occurs.
+ * discarded when one of these signals occurs.
*/
if (sig == SIGTSTP || sig == SIGTTIN || sig == SIGTTOU) {
/*
@@ -211,6 +169,31 @@ _thread_sig_handler(int sig, int code, struct sigcontext * scp)
sigdelset(&pthread->sigpend,SIGCONT);
}
+ /*
+ * Enter a loop to process each thread in the linked
+ * list that is sigwait-ing on a signal. Since POSIX
+ * doesn't specify which thread will get the signal
+ * if there are multiple waiters, we'll give it to the
+ * first one we find.
+ */
+ for (pthread = _thread_link_list; pthread != NULL;
+ pthread = pthread->nxt) {
+ if ((pthread->state == PS_SIGWAIT) &&
+ sigismember(pthread->data.sigwait, sig)) {
+ /* Change the state of the thread to run: */
+ PTHREAD_NEW_STATE(pthread,PS_RUNNING);
+
+ /* Return the signal number: */
+ pthread->signo = sig;
+
+ /*
+ * Do not attempt to deliver this signal
+ * to other threads.
+ */
+ return;
+ }
+ }
+
/* Check if the signal is not being ignored: */
if (_thread_sigact[sig - 1].sa_handler != SIG_IGN)
/*
@@ -255,6 +238,7 @@ _thread_signal(pthread_t pthread, int sig)
case PS_RUNNING:
case PS_STATE_MAX:
case PS_SIGTHREAD:
+ case PS_SIGWAIT:
case PS_SUSPENDED:
/* Nothing to do here. */
break;
@@ -287,7 +271,6 @@ _thread_signal(pthread_t pthread, int sig)
case PS_FDW_WAIT:
case PS_SLEEP_WAIT:
case PS_SELECT_WAIT:
- case PS_SIGWAIT:
if (sig != SIGCHLD ||
_thread_sigact[sig - 1].sa_handler != SIG_DFL) {
/* Flag the operation as interrupted: */
@@ -300,6 +283,21 @@ _thread_signal(pthread_t pthread, int sig)
pthread->signo = sig;
}
break;
+
+ case PS_SIGSUSPEND:
+ /*
+ * Only wake up the thread if the signal is unblocked
+ * and there is a handler installed for the signal.
+ */
+ if (!sigismember(&pthread->sigmask, sig) &&
+ _thread_sigact[sig - 1].sa_handler != SIG_DFL) {
+ /* Change the state of the thread to run: */
+ PTHREAD_NEW_STATE(pthread,PS_RUNNING);
+
+ /* Return the signal number: */
+ pthread->signo = sig;
+ }
+ break;
}
}
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