X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fsparc64%2Flib%2Fdebuglocks.c;h=9fb4dedc89e13934f84bf093bde4ca2145f01825;hb=c7b5ebbddf7bcd3651947760f423e3783bbe6573;hp=341cce76b773237ec16c572fa442c14506b3dd50;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git

diff --git a/arch/sparc64/lib/debuglocks.c b/arch/sparc64/lib/debuglocks.c
index 341cce76b..9fb4dedc8 100644
--- a/arch/sparc64/lib/debuglocks.c
+++ b/arch/sparc64/lib/debuglocks.c
@@ -55,7 +55,7 @@ void _do_spin_lock(spinlock_t *lock, char *str)
 {
 	unsigned long caller, val;
 	int stuck = INIT_STUCK;
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 	int shown = 0;
 
 	GET_CALLER(caller);
@@ -80,12 +80,14 @@ again:
 	lock->owner_cpu = cpu;
 	current->thread.smp_lock_count++;
 	current->thread.smp_lock_pc = ((unsigned int)caller);
+
+	put_cpu();
 }
 
-int _spin_trylock(spinlock_t *lock)
+int _do_spin_trylock(spinlock_t *lock)
 {
 	unsigned long val, caller;
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 
 	GET_CALLER(caller);
 	__asm__ __volatile__("ldstub [%1], %0"
@@ -99,6 +101,9 @@ int _spin_trylock(spinlock_t *lock)
 		current->thread.smp_lock_count++;
 		current->thread.smp_lock_pc = ((unsigned int)caller);
 	}
+
+	put_cpu();
+
 	return val == 0;
 }
 
@@ -117,7 +122,7 @@ void _do_read_lock (rwlock_t *rw, char *str)
 {
 	unsigned long caller, val;
 	int stuck = INIT_STUCK;
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 	int shown = 0;
 
 	GET_CALLER(caller);
@@ -148,13 +153,15 @@ wlock_again:
 	rw->reader_pc[cpu] = ((unsigned int)caller);
 	current->thread.smp_lock_count++;
 	current->thread.smp_lock_pc = ((unsigned int)caller);
+
+	put_cpu();
 }
 
 void _do_read_unlock (rwlock_t *rw, char *str)
 {
 	unsigned long caller, val;
 	int stuck = INIT_STUCK;
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 	int shown = 0;
 
 	GET_CALLER(caller);
@@ -181,13 +188,15 @@ runlock_again:
 		}
 		goto runlock_again;
 	}
+
+	put_cpu();
 }
 
 void _do_write_lock (rwlock_t *rw, char *str)
 {
 	unsigned long caller, val;
 	int stuck = INIT_STUCK;
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 	int shown = 0;
 
 	GET_CALLER(caller);
@@ -263,6 +272,8 @@ wlock_again:
 	rw->writer_cpu = cpu;
 	current->thread.smp_lock_count++;
 	current->thread.smp_lock_pc = ((unsigned int)caller);
+
+	put_cpu();
 }
 
 void _do_write_unlock(rwlock_t *rw)
@@ -299,4 +310,65 @@ wlock_again:
 	}
 }
 
+int _do_write_trylock (rwlock_t *rw, char *str)
+{
+	unsigned long caller, val;
+	int cpu = get_cpu();
+
+	GET_CALLER(caller);
+
+	/* Try to acuire the write bit.  */
+	__asm__ __volatile__(
+"	mov	1, %%g3\n"
+"	sllx	%%g3, 63, %%g3\n"
+"	ldx	[%0], %%g5\n"
+"	brlz,pn	%%g5, 1f\n"
+"	 or	%%g5, %%g3, %%g7\n"
+"	casx	[%0], %%g5, %%g7\n"
+"	membar	#StoreLoad | #StoreStore\n"
+"	ba,pt	%%xcc, 2f\n"
+"	 sub	%%g5, %%g7, %0\n"
+"1:	mov	1, %0\n"
+"2:"	: "=r" (val)
+	: "0" (&(rw->lock))
+	: "g3", "g5", "g7", "memory");
+
+	if (val) {
+		put_cpu();
+		return 0;
+	}
+
+	if ((rw->lock & ((1UL<<63)-1UL)) != 0UL) {
+		/* Readers still around, drop the write
+		 * lock, return failure.
+		 */
+		__asm__ __volatile__(
+"		mov	1, %%g3\n"
+"		sllx	%%g3, 63, %%g3\n"
+"1:		ldx	[%0], %%g5\n"
+"		andn	%%g5, %%g3, %%g7\n"
+"		casx	[%0], %%g5, %%g7\n"
+"		cmp	%%g5, %%g7\n"
+"		bne,pn	%%xcc, 1b\n"
+"		 membar	#StoreLoad | #StoreStore"
+		: /* no outputs */
+		: "r" (&(rw->lock))
+		: "g3", "g5", "g7", "cc", "memory");
+
+		put_cpu();
+
+		return 0;
+	}
+
+	/* We have it, say who we are. */
+	rw->writer_pc = ((unsigned int)caller);
+	rw->writer_cpu = cpu;
+	current->thread.smp_lock_count++;
+	current->thread.smp_lock_pc = ((unsigned int)caller);
+
+	put_cpu();
+
+	return 1;
+}
+
 #endif /* CONFIG_SMP */