use spinlocks in MCS rwlock

arch/x86/kernel/include/arch-lock.h

@@ -208,6 +208,8 @@ static void mcs_lock_unlock(struct mcs_lock_node *lock,
 }
 
 
+#define SPINLOCK_IN_MCS_RWLOCK
+
 // reader/writer lock
 typedef struct mcs_rwlock_node {
 	ihk_atomic_t count;	// num of readers (use only common reader)
@@ -224,21 +226,31 @@ typedef struct mcs_rwlock_node {
 } __attribute__((aligned(64))) mcs_rwlock_node_t;
 
 typedef struct mcs_rwlock_node_irqsave {
+#ifndef SPINLOCK_IN_MCS_RWLOCK
 	struct mcs_rwlock_node node;
+#endif
 	unsigned long irqsave;
 } __attribute__((aligned(64))) mcs_rwlock_node_irqsave_t;
 
 typedef struct mcs_rwlock_lock {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_spinlock_t slock;
+#else
 	struct mcs_rwlock_node reader;		/* common reader lock */
 	struct mcs_rwlock_node *node;		/* base */
+#endif
 } __attribute__((aligned(64))) mcs_rwlock_lock_t;
 
 static void
 mcs_rwlock_init(struct mcs_rwlock_lock *lock)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_mc_spinlock_init(&lock->slock);
+#else
 	ihk_atomic_set(&lock->reader.count, 0);
 	lock->reader.type = MCS_RWLOCK_TYPE_COMMON_READER;
 	lock->node = NULL;
+#endif
 }
 
 #ifdef DEBUG_MCS_RWLOCK
@@ -253,6 +265,9 @@ __kprintf("[%d] ret mcs_rwlock_writer_lock_noirq\n", ihk_mc_get_processor_id());
 static void
 __mcs_rwlock_writer_lock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_mc_spinlock_lock_noirq(&lock->slock);
+#else
 	struct mcs_rwlock_node *pred;
 
 	preempt_disable();
@@ -270,8 +285,10 @@ __mcs_rwlock_writer_lock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock_n
 			cpu_pause();
 		}
 	}
+#endif
 }
 
+#ifndef SPINLOCK_IN_MCS_RWLOCK
 static void
 mcs_rwlock_unlock_readers(struct mcs_rwlock_lock *lock)
 {
@@ -328,6 +345,7 @@ mcs_rwlock_unlock_readers(struct mcs_rwlock_lock *lock)
 
 	f->locked = MCS_RWLOCK_UNLOCKED;
 }
+#endif
 
 #ifdef DEBUG_MCS_RWLOCK
 #define mcs_rwlock_writer_unlock_noirq(l, n) { \
@@ -341,6 +359,9 @@ __kprintf("[%d] ret mcs_rwlock_writer_unlock_noirq\n", ihk_mc_get_processor_id()
 static void
 __mcs_rwlock_writer_unlock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_mc_spinlock_unlock_noirq(&lock->slock);
+#else
 	if (node->next == NULL) {
 		struct mcs_rwlock_node *old = (struct mcs_rwlock_node *)
 			atomic_cmpxchg8((unsigned long *)&lock->node,
@@ -365,6 +386,7 @@ __mcs_rwlock_writer_unlock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock
 
 out:
 	preempt_enable();
+#endif
 }
 
 #ifdef DEBUG_MCS_RWLOCK
@@ -397,6 +419,9 @@ atomic_inc_ifnot0(ihk_atomic_t *v)
 static void
 __mcs_rwlock_reader_lock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_mc_spinlock_lock_noirq(&lock->slock);
+#else
 	struct mcs_rwlock_node *pred;
 
 	preempt_disable();
@@ -445,6 +470,7 @@ __mcs_rwlock_reader_lock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock_n
 	}
 out:
 	return;
+#endif
 }
 
 #ifdef DEBUG_MCS_RWLOCK
@@ -459,6 +485,9 @@ __kprintf("[%d] ret mcs_rwlock_reader_unlock_noirq\n", ihk_mc_get_processor_id()
 static void
 __mcs_rwlock_reader_unlock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_mc_spinlock_unlock_noirq(&lock->slock);
+#else
 	if(ihk_atomic_dec_return(&lock->reader.count))
 		goto out;
 
@@ -488,6 +517,7 @@ __mcs_rwlock_reader_unlock_noirq(struct mcs_rwlock_lock *lock, struct mcs_rwlock
 
 out:
 	preempt_enable();
+#endif
 }
 
 #ifdef DEBUG_MCS_RWLOCK
@@ -502,8 +532,12 @@ __kprintf("[%d] ret mcs_rwlock_writer_lock\n", ihk_mc_get_processor_id()); \
 static void
 __mcs_rwlock_writer_lock(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node_irqsave *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	node->irqsave = ihk_mc_spinlock_lock(&lock->slock);
+#else
 	node->irqsave = cpu_disable_interrupt_save();
 	__mcs_rwlock_writer_lock_noirq(lock, &node->node);
+#endif
 }
 
 #ifdef DEBUG_MCS_RWLOCK
@@ -518,8 +552,12 @@ __kprintf("[%d] ret mcs_rwlock_writer_unlock\n", ihk_mc_get_processor_id()); \
 static void
 __mcs_rwlock_writer_unlock(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node_irqsave *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_mc_spinlock_unlock(&lock->slock, node->irqsave);
+#else
 	__mcs_rwlock_writer_unlock_noirq(lock, &node->node);
 	cpu_restore_interrupt(node->irqsave);
+#endif
 }
 
 #ifdef DEBUG_MCS_RWLOCK
@@ -534,8 +572,12 @@ __kprintf("[%d] ret mcs_rwlock_reader_lock\n", ihk_mc_get_processor_id()); \
 static void
 __mcs_rwlock_reader_lock(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node_irqsave *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	node->irqsave = ihk_mc_spinlock_lock(&lock->slock);
+#else
 	node->irqsave = cpu_disable_interrupt_save();
 	__mcs_rwlock_reader_lock_noirq(lock, &node->node);
+#endif
 }
 
 #ifdef DEBUG_MCS_RWLOCK
@@ -550,8 +592,12 @@ __kprintf("[%d] ret mcs_rwlock_reader_unlock\n", ihk_mc_get_processor_id()); \
 static void
 __mcs_rwlock_reader_unlock(struct mcs_rwlock_lock *lock, struct mcs_rwlock_node_irqsave *node)
 {
+#ifdef SPINLOCK_IN_MCS_RWLOCK
+	ihk_mc_spinlock_unlock(&lock->slock, node->irqsave);
+#else
 	__mcs_rwlock_reader_unlock_noirq(lock, &node->node);
 	cpu_restore_interrupt(node->irqsave);
+#endif
 }
 
 #endif

kernel/fileobj.c

@@ -29,8 +29,7 @@
 #define	dkprintf(...)	do { if (0) kprintf(__VA_ARGS__); } while (0)
 #define	ekprintf(...)	kprintf(__VA_ARGS__)
 
-mcs_rwlock_lock_t fileobj_list_lock =
+mcs_rwlock_lock_t fileobj_list_lock;
-	{{{0}, MCS_RWLOCK_TYPE_COMMON_READER, 0, 0, 0, NULL}, NULL};
 static LIST_HEAD(fileobj_list);
 
 #define FILEOBJ_PAGE_HASH_SHIFT 9

kernel/process.c

@@ -3224,6 +3224,7 @@ process_unlock(struct process *proc, struct mcs_rwlock_node_irqsave *lock)
 void
 debug_log(unsigned long arg)
 {
+#if 0
 	struct process *p;
 	struct thread *t;
 	int i;
@@ -3276,4 +3277,5 @@ debug_log(unsigned long arg)
 		}
 		break;
 	}
+#endif
 }