signal: When the process receives a termination signal, it first terminates mcexec.

refs #863
refs #870

arch/x86_64/kernel/syscall.c

@@ -32,6 +32,7 @@
 #include <limits.h>
 #include <syscall.h>
 
+void terminate_mcexec(int, int);
 extern long do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact);
 long syscall(int num, ihk_mc_user_context_t *ctx);
 void set_signal(int sig, void *regs0, siginfo_t *info);
@@ -1116,7 +1117,15 @@ check_sig_pending()
 	}
 
 	if (found) {
-		interrupt_syscall(thread, 0);
+		if (sig != SIGCHLD && sig != SIGURG &&
+		    thread->sigcommon->action[sig - 1].sa.sa_handler == NULL) {
+			terminate_mcexec(0, sig);
+		}
+		else if (thread->sigcommon->action[sig - 1].sa.sa_handler &&
+		         thread->sigcommon->action[sig - 1].sa.sa_handler !=
+		                                                   (void *)1) {
+			interrupt_syscall(thread, 0);
+		}
 	}
 }
 

kernel/include/process.h

@@ -488,7 +488,7 @@ struct process {
 			// V       +----   |
 			// PS_STOPPED -----+
 			// (PS_TRACED)
-	int exit_status; // only for zombie
+	unsigned long exit_status; // only for zombie
 
 	/* Store exit_status for a group of threads when stopped by SIGSTOP.
 	   exit_status can't be used because values of exit_status of threads

kernel/syscall.c

@@ -957,6 +957,28 @@ SYSCALL_DECLARE(waitid)
 	return 0;
 }
 
+void terminate_mcexec(int rc, int sig)
+{
+	unsigned long old_exit_status;
+	unsigned long exit_status;
+	struct thread *mythread = cpu_local_var(current);
+	struct process *proc = mythread->proc;
+	struct syscall_request request IHK_DMA_ALIGN;
+
+	if ((old_exit_status = proc->exit_status) & 0x0000000100000000L)
+		return;
+	exit_status = 0x0000000100000000L | ((rc & 0x00ff) << 8) | (sig & 0xff);
+	if (!__sync_bool_compare_and_swap(&proc->exit_status,
+	                                  old_exit_status, exit_status))
+		return;
+	if (!proc->nohost) {
+		request.number = __NR_exit_group;
+		request.args[0] = proc->exit_status;
+		proc->nohost = 1;
+		do_syscall(&request, ihk_mc_get_processor_id(), proc->pid);
+	}
+}
+
 void terminate(int rc, int sig)
 {
 	struct resource_set *resource_set = cpu_local_var(resource_set);
@@ -974,7 +996,6 @@ void terminate(int rc, int sig)
 	int i;
 	int n;
 	int *ids = NULL;
-	struct syscall_request request IHK_DMA_ALIGN;
 	int exit_status;
 
 	// sync perf info
@@ -996,8 +1017,11 @@ void terminate(int rc, int sig)
 		return;
 	}
 
-	exit_status = mythread->exit_status = ((rc & 0x00ff) << 8) | (sig & 0xff);
+	exit_status = ((rc & 0x00ff) << 8) | (sig & 0xff);
+	mythread->exit_status = exit_status;
 	proc->status = PS_EXITED;
+	terminate_mcexec(rc, sig);
+
 	mcs_rwlock_writer_unlock_noirq(&proc->update_lock, &updatelock);
 	mcs_rwlock_reader_unlock(&proc->threads_lock, &lock);
 
@@ -1145,19 +1169,7 @@ void terminate(int rc, int sig)
 #endif
 
 	// clean up memory
-	if (!proc->nohost) {
-		request.number = __NR_exit_group;
-		request.args[0] = exit_status;
-#ifdef POSTK_DEBUG_TEMP_FIX_48 /* nohost flag missed fix */
-		proc->nohost = 1;
-		do_syscall(&request, ihk_mc_get_processor_id(), proc->pid);
-#else /* POSTK_DEBUG_TEMP_FIX_48 */
-		do_syscall(&request, ihk_mc_get_processor_id(), proc->pid);
-		proc->nohost = 1;
-#endif /* POSTK_DEBUG_TEMP_FIX_48 */
-	}
 
-	proc->exit_status = exit_status;
 	finalize_process(proc);
 
 	preempt_disable();