From 10190e9ed69f7dff7a943954e405830b425d3b15 Mon Sep 17 00:00:00 2001
From: Tomoki Shirasawa <sira@popeye.cc.u-tokyo.ac.jp>
Date: Fri, 25 Jul 2014 09:17:43 +0900
Subject: [PATCH] prepare for a condition variable for each process.
 (Redmine#193)

---
 executer/kernel/control.c | 7 ++++---
 executer/kernel/mcctrl.h  | 2 +-
 executer/kernel/syscall.c | 4 ++--
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/executer/kernel/control.c b/executer/kernel/control.c
index 4b0c837d..3a3bd6ae 100644
--- a/executer/kernel/control.c
+++ b/executer/kernel/control.c
@@ -330,12 +330,13 @@ retry_alloc:
 		}
 
 		wqhln->pid = pid;
+		wqhln->req = 0;
 		init_waitqueue_head(&wqhln->wq_syscall);
 		list_add_tail(&wqhln->list, &c->wq_list);
 	}
 	ihk_ikc_spinlock_unlock(&c->wq_list_lock, flags);
 
-	c->req = 1;
+	wqhln->req = 1;
 	wake_up(&wqhln->wq_syscall);
 
 	return 0;
@@ -388,6 +389,7 @@ retry_alloc:
 	}
 
 	wqhln->pid = swd.pid;	
+	wqhln->req = 0;
 	init_waitqueue_head(&wqhln->wq_syscall);
 	
 	irqflags = ihk_ikc_spinlock_lock(&c->wq_list_lock);
@@ -403,7 +405,7 @@ retry_alloc:
 	list_add_tail(&wqhln->list, &c->wq_list);
 	ihk_ikc_spinlock_unlock(&c->wq_list_lock, irqflags);
 
-	ret = wait_event_interruptible(wqhln->wq_syscall, c->req);
+	ret = wait_event_interruptible(wqhln->wq_syscall, wqhln->req);
 	
 	/* Remove per-process wait queue head */
 	irqflags = ihk_ikc_spinlock_lock(&c->wq_list_lock);
@@ -427,7 +429,6 @@ retry_alloc:
 		return -EINTR;
 	}
 
-	c->req = 0;
 #if 1
 	mb();
 	if (!c->param.request_va->valid) {
diff --git a/executer/kernel/mcctrl.h b/executer/kernel/mcctrl.h
index 26c5adcb..0266068f 100644
--- a/executer/kernel/mcctrl.h
+++ b/executer/kernel/mcctrl.h
@@ -93,6 +93,7 @@ struct wait_queue_head_list_node {
 	struct list_head list;
 	wait_queue_head_t wq_syscall;
 	int pid;
+	int req;
 };
 
 struct mcctrl_channel {
@@ -101,7 +102,6 @@ struct mcctrl_channel {
 	struct ikc_scd_init_param init;
 	void *dma_buf;
 
-	int req;
 	struct list_head wq_list;
 	ihk_spinlock_t wq_list_lock;
 };
diff --git a/executer/kernel/syscall.c b/executer/kernel/syscall.c
index a748fdf2..e35f1e0e 100644
--- a/executer/kernel/syscall.c
+++ b/executer/kernel/syscall.c
@@ -255,6 +255,7 @@ retry_alloc:
 
 		/* Prepare per-process wait queue head */
 		wqhln->pid = current->tgid;	
+		wqhln->req = 0;
 		init_waitqueue_head(&wqhln->wq_syscall);
 
 		irqflags = ihk_ikc_spinlock_lock(&channel->wq_list_lock);
@@ -271,7 +272,7 @@ retry_alloc:
 		ihk_ikc_spinlock_unlock(&channel->wq_list_lock, irqflags);
 
 		/* wait for response */
-		error = wait_event_interruptible(wqhln->wq_syscall, channel->req);
+		error = wait_event_interruptible(wqhln->wq_syscall, wqhln->req);
 
 		/* Remove per-process wait queue head */
 		irqflags = ihk_ikc_spinlock_lock(&channel->wq_list_lock);
@@ -283,7 +284,6 @@ retry_alloc:
 			printk("remote_page_fault:interrupted. %d\n", error);
 			goto out;
 		}
-		channel->req = 0;
 		if (!req->valid) {
 			printk("remote_page_fault:not valid\n");
 		}