From a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Wed, 5 Aug 2026 07:52:36 -0700 Subject: workqueue: skip the node_nr_active update for non-unbound workqueues 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 Signed-off-by: Tejun Heo --- include/asm-generic/cmpxchg-local.h | 68 +++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 include/asm-generic/cmpxchg-local.h (limited to 'include/asm-generic/cmpxchg-local.h') diff --git a/include/asm-generic/cmpxchg-local.h b/include/asm-generic/cmpxchg-local.h new file mode 100644 index 000000000..f27d66fdc --- /dev/null +++ b/include/asm-generic/cmpxchg-local.h @@ -0,0 +1,68 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_CMPXCHG_LOCAL_H +#define __ASM_GENERIC_CMPXCHG_LOCAL_H + +#include +#include + +extern unsigned long wrong_size_cmpxchg(volatile void *ptr) + __noreturn; + +/* + * Generic version of __cmpxchg_local (disables interrupts). Takes an unsigned + * long parameter, supporting various types of architectures. + */ +static inline unsigned long __generic_cmpxchg_local(volatile void *ptr, + unsigned long old, unsigned long new, int size) +{ + unsigned long flags, prev; + + /* + * Sanity checking, compile-time. + */ + if (size == 8 && sizeof(unsigned long) != 8) + wrong_size_cmpxchg(ptr); + + raw_local_irq_save(flags); + switch (size) { + case 1: prev = *(u8 *)ptr; + if (prev == (old & 0xffu)) + *(u8 *)ptr = (new & 0xffu); + break; + case 2: prev = *(u16 *)ptr; + if (prev == (old & 0xffffu)) + *(u16 *)ptr = (new & 0xffffu); + break; + case 4: prev = *(u32 *)ptr; + if (prev == (old & 0xffffffffu)) + *(u32 *)ptr = (new & 0xffffffffu); + break; + case 8: prev = *(u64 *)ptr; + if (prev == old) + *(u64 *)ptr = (u64)new; + break; + default: + wrong_size_cmpxchg(ptr); + } + raw_local_irq_restore(flags); + return prev; +} + +/* + * Generic version of __cmpxchg64_local. Takes an u64 parameter. + */ +static inline u64 __generic_cmpxchg64_local(volatile void *ptr, + u64 old, u64 new) +{ + u64 prev; + unsigned long flags; + + raw_local_irq_save(flags); + prev = *(u64 *)ptr; + if (prev == old) + *(u64 *)ptr = new; + raw_local_irq_restore(flags); + return prev; +} + +#endif -- cgit v1.3.1