workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted

apply_wqattrs_commit() updates node_nr_active->max unconditionally.
wq->node_nr_active[] is only allocated for unbound workqueues, so guard
the call before per-cpu workqueues start using this path.

No functional change: only unbound workqueues reach apply_wqattrs_*()
today.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 197 insertions, 0 deletions

diff --git a/arch/sparc/lib/atomic32.c b/arch/sparc/lib/atomic32.c
new file mode 100644
index 000000000..8ae880ebf
--- /dev/null
+++ b/arch/sparc/lib/atomic32.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * atomic32.c: 32-bit atomic_t implementation
+ *
+ * Copyright (C) 2004 Keith M Wesolowski
+ * Copyright (C) 2007 Kyle McMartin
+ * 
+ * Based on asm-parisc/atomic.h Copyright (C) 2000 Philipp Rumpf
+ */
+
+#include <linux/atomic.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+
+#ifdef CONFIG_SMP
+#define ATOMIC_HASH_SIZE	4
+#define ATOMIC_HASH(a)	(&__atomic_hash[(((unsigned long)a)>>8) & (ATOMIC_HASH_SIZE-1)])
+
+spinlock_t __atomic_hash[ATOMIC_HASH_SIZE] = {
+	[0 ... (ATOMIC_HASH_SIZE-1)] = __SPIN_LOCK_UNLOCKED(__atomic_hash)
+};
+
+#else /* SMP */
+
+static DEFINE_SPINLOCK(dummy);
+#define ATOMIC_HASH_SIZE	1
+#define ATOMIC_HASH(a)		(&dummy)
+
+#endif /* SMP */
+
+#define ATOMIC_FETCH_OP(op, c_op)					\
+int arch_atomic_fetch_##op(int i, atomic_t *v)				\
+{									\
+	int ret;							\
+	unsigned long flags;						\
+	spin_lock_irqsave(ATOMIC_HASH(v), flags);			\
+									\
+	ret = v->counter;						\
+	v->counter c_op i;						\
+									\
+	spin_unlock_irqrestore(ATOMIC_HASH(v), flags);			\
+	return ret;							\
+}									\
+EXPORT_SYMBOL(arch_atomic_fetch_##op);
+
+#define ATOMIC_OP_RETURN(op, c_op)					\
+int arch_atomic_##op##_return(int i, atomic_t *v)			\
+{									\
+	int ret;							\
+	unsigned long flags;						\
+	spin_lock_irqsave(ATOMIC_HASH(v), flags);			\
+									\
+	ret = (v->counter c_op i);					\
+									\
+	spin_unlock_irqrestore(ATOMIC_HASH(v), flags);			\
+	return ret;							\
+}									\
+EXPORT_SYMBOL(arch_atomic_##op##_return);
+
+ATOMIC_OP_RETURN(add, +=)
+
+ATOMIC_FETCH_OP(add, +=)
+ATOMIC_FETCH_OP(and, &=)
+ATOMIC_FETCH_OP(or, |=)
+ATOMIC_FETCH_OP(xor, ^=)
+
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+
+int arch_atomic_xchg(atomic_t *v, int new)
+{
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(ATOMIC_HASH(v), flags);
+	ret = v->counter;
+	v->counter = new;
+	spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
+	return ret;
+}
+EXPORT_SYMBOL(arch_atomic_xchg);
+
+int arch_atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(ATOMIC_HASH(v), flags);
+	ret = v->counter;
+	if (likely(ret == old))
+		v->counter = new;
+
+	spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
+	return ret;
+}
+EXPORT_SYMBOL(arch_atomic_cmpxchg);
+
+int arch_atomic_fetch_add_unless(atomic_t *v, int a, int u)
+{
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(ATOMIC_HASH(v), flags);
+	ret = v->counter;
+	if (ret != u)
+		v->counter += a;
+	spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
+	return ret;
+}
+EXPORT_SYMBOL(arch_atomic_fetch_add_unless);
+
+/* Atomic operations are already serializing */
+void arch_atomic_set(atomic_t *v, int i)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(ATOMIC_HASH(v), flags);
+	v->counter = i;
+	spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
+}
+EXPORT_SYMBOL(arch_atomic_set);
+
+unsigned long sp32___set_bit(unsigned long *addr, unsigned long mask)
+{
+	unsigned long old, flags;
+
+	spin_lock_irqsave(ATOMIC_HASH(addr), flags);
+	old = *addr;
+	*addr = old | mask;
+	spin_unlock_irqrestore(ATOMIC_HASH(addr), flags);
+
+	return old & mask;
+}
+EXPORT_SYMBOL(sp32___set_bit);
+
+unsigned long sp32___clear_bit(unsigned long *addr, unsigned long mask)
+{
+	unsigned long old, flags;
+
+	spin_lock_irqsave(ATOMIC_HASH(addr), flags);
+	old = *addr;
+	*addr = old & ~mask;
+	spin_unlock_irqrestore(ATOMIC_HASH(addr), flags);
+
+	return old & mask;
+}
+EXPORT_SYMBOL(sp32___clear_bit);
+
+unsigned long sp32___change_bit(unsigned long *addr, unsigned long mask)
+{
+	unsigned long old, flags;
+
+	spin_lock_irqsave(ATOMIC_HASH(addr), flags);
+	old = *addr;
+	*addr = old ^ mask;
+	spin_unlock_irqrestore(ATOMIC_HASH(addr), flags);
+
+	return old & mask;
+}
+EXPORT_SYMBOL(sp32___change_bit);
+
+#define CMPXCHG(T)						\
+	T __cmpxchg_##T(volatile T *ptr, T old, T new)		\
+	{							\
+		unsigned long flags;				\
+		T prev;						\
+								\
+		spin_lock_irqsave(ATOMIC_HASH(ptr), flags);	\
+		if ((prev = *ptr) == old)			\
+			*ptr = new;				\
+		spin_unlock_irqrestore(ATOMIC_HASH(ptr), flags);\
+								\
+		return prev;					\
+	}
+
+CMPXCHG(u8)
+CMPXCHG(u16)
+CMPXCHG(u32)
+CMPXCHG(u64)
+EXPORT_SYMBOL(__cmpxchg_u8);
+EXPORT_SYMBOL(__cmpxchg_u16);
+EXPORT_SYMBOL(__cmpxchg_u32);
+EXPORT_SYMBOL(__cmpxchg_u64);
+
+unsigned long __xchg_u32(volatile u32 *ptr, u32 new)
+{
+	unsigned long flags;
+	u32 prev;
+
+	spin_lock_irqsave(ATOMIC_HASH(ptr), flags);
+	prev = *ptr;
+	*ptr = new;
+	spin_unlock_irqrestore(ATOMIC_HASH(ptr), flags);
+
+	return (unsigned long)prev;
+}
+EXPORT_SYMBOL(__xchg_u32);